This is a scanned version of the text of the original Soil Survey report of Jackson County Area, Oregon issued August 1993. Original tables and maps were deleted. There may be references in the text that refer to a table that is not in this document.

Updated tables were generated from the NRCS National Soil Information System (NASIS). The soil map data has been digitized and may include some updated information. These are available from http://soildatamart.nrcs.usda.gov.

Please contact the State Soil Scientist, Natural Resources Conservation Service (formerly Soil Conservation Service) for additional information.

Foreword

This soil survey contains information that can be used in land-planning programs in the Jackson County Area. It contains predictions of soil behavior for selected land uses. The survey also highlights limitations and hazards inherent in the soil, improvements needed to overcome the limitations, and the impact of selected land uses on the environment. This soil survey is designed for many different users. Farmers, ranchers, foresters, and agronomists can use it to evaluate the potential of the soil and the management needed for the maximum food and fiber production. Planners, community officials, engineers, developers, builders, and home buyers can use the survey to plan land use, select sites for construction, and identify special practices needed to ensure proper performance. Conservationists, teachers, students, and specialists in recreation, wildlife management, waste disposal, and pollution control can use the survey to help them understand, protect, and enhance the environment. Great differences in soil properties can occur within short distances. Some soils are seasonally wet or subject to flooding. Some are shallow to bedrock. Some are too unstable to be used as a foundation for buildings or roads. Clayey or wet soils are poorly suited to use as septic tank absorption fields. A high water table makes a soil poorly suited to basements or underground installations. These and many other soil properties that affect land use are described in this soil survey. Broad areas of soils are shown on the general soil map. The location of each soil is shown on the detailed soil maps. Each soil in the survey area is described. Information on specific uses is given for each soil. Help in using this publication and additional information are available at the local office of the Soil Conservation Service or the Cooperative Extension Service.

Jack P. Kanalz State Conservationist Soil Conservation Service Soil Survey of Jackson County Area, Oregon

By David R. Johnson, Soil Conservation Service

Fieldwork by David R. Johnson, Duane Setness, Russell A. Almaraz, Roger Borine, Laurel Fischer Mueller, and Roger Pfenninger, Soil Conservation Service

United States Department of Agriculture, Soil Conservation Service, in cooperation with United States Department of the Interior, Bureau of Land Management; United States Department of Agriculture, Forest Service; and Oregon Agricultural Experiment Station

This survey area is in the southwestern part of Oregon (fig. 1). It consists of most of Jackson County and the southwestern part of Klamath County. It borders California to the south. Medford, the largest city in the survey area, is the county seat of Jackson County. Elevation ranges from 970 feet in an area where the Rogue River crosses into Josephine County to nearly 6,600 feet in an area on Hamaker Mountain, in Klamath County. The total extent of the survey area is 1,585,308 acres. Of this total, 1,352,189 acres is in Jackson County and 233,119 acres is in Klamath County. About 1,042,308 acres is privately owned, and 543,000 acres is publicly owned. About 456,000 acres of the publicly owned land is managed by the Bureau of Land Management, 40,000 acres by the Forest Service, and 7,000 acres by other federal agencies. The remaining 40,000 acres is managed by the State of Oregon or by local governments. The economy of the survey area is based mainly on Figure 1.-Location of Jackson County Area in Oregon. forestry, agriculture, manufacturing, tourism, and cattle ranching. The favorable location of the area relative to rock, and scattered areas of ultramafic rock. The soils in major transportation corridors facilitates the growth of the the river valleys and on the adjacent foot slopes formed in economy. alluvium derived from mixed sources. The survey area has more than 110 different kinds of This survey updates soil surveys published in 1969, soil. The soils formed in a variety of parent materials. The 1920, and 1913 (25, 14, 22). It provides additional soils in the Cascade Mountains formed in colluvium and information. residuum derived from andesite, basalt, tuff, breccia, volcanic ash, and pumice. Those in the Klamath Mountains General Nature of the Survey Area formed in colluvium and residuum derived from granite, This section gives general information about the altered igneous and sedimentary survey area. It describes history and development; physiography, relief, and drainage; and climate. History and Development considered this lumber boomtown the liveliest town between San Francisco and Portland (6). The town Several linguistically distinct Indian tribes inhabited the suffered a major fire and was never rebuilt. survey area before the immigration of non-Indian settlers Hay, cereal crops, and tree fruit were the earliest (8). The tribes included the Upland Takilma, the Shasta, the commercial crops grown in the survey area. The population Dakubetede, and the Klamath. The Upland Takilma lived in of Medford doubled between 1910 and 1915 as fruit the upper reaches of the valley of Bear Creek, in the valley growers arrived in response to nationwide advertising of the of the Rogue River, and in the nearby mountains. The area as an ideal place for the production of tree fruit. The Shasta lived in the valley of Bear Creek, in the Ashland main agricultural products today are tree fruit, especially area. The Dakubetede lived in the valley of the Applegate pears; hay and row crops; and dairy products', beef, and River, near what is now the community of Ruch. The poultry. Klamath seasonally hunted and harvested edible plants in The first effort to bring irrigation water to the survey area the High Cascades. began in 1905, when the Fish Lake Water Company was The Indians occupied semipermanent villages close to established. Irrigation water currently is provided by a sources of food and other needs. They periodically burned system of diversion canals developed by the Medford and some areas in order to increase the growth of edible plants, Talent Irrigation Districts. including huckleberry bushes and browse for big game (5). As farming, ranching, and timber harvesting In the 1850's, there were hostilities between the Indians and continued, concerns about the use of the land and water miners in the survey area. The armed conflicts drastically resources became important. In response to these reduced the Indian population. Many of those who survived concerns, land owners organized the Jackson Soil and lived on the Table Rock Reservation before they were Water Conservation District in 1951 and the Rogue Soil moved to reservations in the Willamette Valley. and Water Conservation District in 1953. The present In 1827, a party of trappers from the Hudson Bay Jackson County Soil and Water Conservation District Company entered the survey area. It explored the area was formed in 1966 through the consolidation of both of while trapping animals along streams (27). The early these earlier districts. trappers opened up a route to California, which later Demands on the natural resources of the survey area became important during the gold rush. The route was have been intensified by an increase in population, which near the present course of Interstate Highway 5. has more than doubled since the organization of the After the discovery of placer gold near Jacksonville in conservation district. This increase has created new 1852, many miners entered into the survey area. They were problems of water quality, thereby increasing the complexity a culturally diverse group, as is revealed in such place of water management and drainage issues. names as China Gulch, Kanaka Flats, and Negro Ben Tourism is an important part of the economy in the Mountain. Mexican packers brought in food and other survey area. The major outdoor recreational activities are supplies from California (27). Many Chinese were brought in visiting Crater Lake National Park, hiking the Pacific Crest to work the mines. Mineral resources continued to be Trail, river rafting, and fishing. In winter Mt. Ashland offers important to the economy of the survey area well after the opportunities for skiing. turn of the century. Jackson County was established by an act of the Territorial Legislature in 1852. At that time the county Physiography, Relief, and Drainage included most of the counties that presently make up the The valleys of the Rogue River and Bear Creek, in the southwestern part of Oregon. It was named after General central part of the survey area, are characterized by Andrew Jackson. Jacksonville was the first county seat. moderate relief. They consist of flood plains, terraces, In 1927, the county seat was moved to Medford. alluvial fans, and hills, which formed through erosion and The industry and population of the survey area the extensive deposition of alluvial outwash following the expanded following the arrival of the railroad in 1883. By uplift of the surrounding mountains. 1900, timber production had replaced mining as the main The major drainageways in the survey area are the industry. The timber industry flourished as the means of Rogue, Applegate, and Klamath Rivers and Bear, Evans, shipping goods to distant markets improved. Little Butte, Big Butte, Antelope, and Jenny Creeks. Some of The Klamath River was used to transport logs and these drainageways are in broad, fertile alluvial valleys. lumber downstream. Pokegema, near the banks of the Others, such as the Klamath River and Jenny Creek, are river, was one of the early logging towns established entrenched in deeply incised canyons. Most of the streams before the turn of the century. Travelers once in the survey area drain into the Rogue River and its tributary, the Applegate River. Most areas of the High Cascades, in the eastern part of the survey area, are drained by streams equivalent to "heat units." During the month, growing flowing generally south into the Klamath River. degree days accumulate by the amount that the average East and north of the interior valleys are the Cascade temperature each day exceeds a base temperature (40 Mountains, which are of volcanic origin. The western flank of degrees F). The normal monthly accumulation is used to the Cascade Mountains is the oldest part of this range. It schedule single or successive plantings of a crop between has been deeply dissected by erosion. It gradually grades the last freeze in spring and the first freeze in fall. into the geologically younger High Cascades, which are The total annual precipitation is about 20 inches at characterized by broad plateaus and slopes of moderate Medford, 42 inches at Prospect, and 27 inches at Ruch. Of relief that have been only slightly modified by erosion. these totals, 20 percent usually falls in April through, The Klamath Mountains, in the western part of the survey September. The growing season for most crops usually falls area, are steep and are characterized by strong relief. They within this period. The heaviest 1-day rainfall during the are made up mainly of metamorphic and granitic rock. The period of record was 4.39 inches at Prospect on December metamorphic rock is highly folded and faulted. In many 22, 1964. Thunderstorms occur on about 9 days each year, places the granitic rock has intruded into the metamorphic and most occur in spring. rock and occurs as scattered small bodies throughout the The average seasonal snowfall is about 10 inches at survey area. In areas south of Ashland and near West Medford, 70 inches at Prospect, and 22 inches at Ruch. The Evans Creek, in the northwestern part of the survey area, greatest snow depth at any one time during the period of however, the granite occurs as bodies that are several record was 7 inches at Medford, 33 inches at Prospect, and square miles in size. Erosion has modified these 12 inches at Ruch. On the average, 2 days at Medford, 22 geologically old mountains. days at prospect, and 5 days at Ruch have at least 1 inch of snow on the ground. The number of such days varies greatly from year to year. The average relative humidity in midafternoon is about Climate 45 percent. Humidity is higher at night, and the average Prepared by the National Climatic Data Center, Asheville, North Carolina. at dawn is about 85 percent. The sun shines 70 percent The climate of the survey area is tempered by wind of the time in summer and 25 percent in winter. The from the Pacific Ocean. Summers are warm. Winters are prevailing wind is from the northwest. Average cool, but snow and freezing temperatures are common windspeed is highest, 6 miles per hour, in spring. only at the higher elevations. In summer rainfall is In most winters one or two storms bring strong and extremely light. As a result, crops require irrigation. sometimes damaging winds. In some years the Several weeks often pass without precipitation. Rains are accompanying heavy rains cause serious flooding. Every frequent during the rest of the year, especially late in fall few years the invasion of a large continental airmass from and in winter. the east causes abnormal temperatures either in winter or Table 1 gives data on temperature and precipitation for in spring. In winter several consecutive days are well below the survey area as recorded at Medford, Prospect, and freezing. In summer a week or more is sweltering. Ruch, Oregon, in the period 1951 to 1979. Table 2 shows probable dates of the first freeze in fall and the last freeze in spring. Table 3 provides data on length of the growing season. In winter, the average temperature at Medford, Prospect, How This Survey Was Made and Ruch is 39, 38, and 40 degrees F, respectively. The average daily minimum temperature is 31 degrees at This survey was made to provide information about the Medford, 28 degrees at Prospect, and 30 degrees at Ruch. soils and miscellaneous areas in the survey area. The The lowest temperature on record, which occurred at information includes a description of the soils and Prospect on January 22, 1962, is -8 degrees. In summer, miscellaneous areas and their location and a discussion of the average temperature is 70 degrees at Medford, 65 their suitability, limitations, and management for specified degrees at prospect, and 68 degrees at Ruch. The average uses. Soil scientists observed the steepness, length, and daily maximum temperature is about 86 degrees. The shape of the slopes; the general pattern of drainage; the highest recorded temperature, which occurred at Medford kinds of crops and native plants; and the kinds of bedrock. on August 8, 1978, is 110 degrees. They dug many holes to study the soil profile, which is the Growing degree days are shown in table 1. They are sequence of natural layers, or horizons, in a soil. The profile extends from the surface down into the unconsolidated material in which the soil formed. The unconsolidated material is devoid of roots the soils are field tested through observation of the soils in and other living organisms and has not been changed by different uses and under different levels of management. other biological activity. Some interpretations are modified to fit local conditions, and The soils and miscellaneous areas in the survey area are some new interpretations are developed to meet local in a pattern that is related to the geology, landforms, relief, needs. Data are assembled from other sources, such as climate, and natural vegetation of the area. Each kind of soil research information, production records, and field and miscellaneous area is associated with a particular kind experience of specialists. For example, data on crop yields or segment of the landscape. By observing the soils and under defined levels of management are assembled from miscellaneous areas in the survey area and relating their farm records and from field or plot experiments on the same position to specific segments of the landscape, a soil kinds of soil. scientist develops a concept, or model, of how they were Predictions about soil behavior are based not only on soil formed. Thus, during mapping, this model enables the soil properties but also on such variables as climate and scientist to predict with a considerable degree of accuracy biological activity. Soil conditions are predictable over long the kind of soil or miscellaneous area at a specific location periods of time, but they are not predictable from year to on the landscape. year. For example, soil scientists can predict with a fairly Individual soils on the landscape commonly merge high degree of accuracy that a given soil will have a high gradually into one another as their characteristics gradually water table within certain depths in most years, but they change. To construct an accurate map, however, soil cannot predict that a high water table will always be at a scientists must determine the boundaries between the soils. specific level in the soil on a specific date. They can observe only a limited number of soil profiles. After soil scientists located and identified the significant Nevertheless, these observations, supplemented by an natural bodies of soil in the survey area, they drew the understanding of the soil-vegetation-landscape relationship, boundaries of these bodies on aerial photographs and are sufficient to verify predictions of the kinds of soil in an identified each as a specific map unit. Aerial photographs area and to determine the boundaries. show trees, buildings, fields, roads, and rivers, all of which Soil scientists recorded the characteristics of the soil help in locating boundaries accurately. profiles that they studied. They noted color, texture, size, The descriptions, names, and delineations of the soils in and shape of soil aggregates, kind and amount of rock this survey area do not fully agree with those of the soils in fragments, distribution of plant roots, reaction, and other adjacent survey areas. Differences are the result of a better features that enable them to identify soils. After describing knowledge of soils, modifications in series concepts, or the soils in the survey area and determining their properties, variations in the intensity of mapping or in the extent of the soil scientists assigned the soils to taxonomic classes soils in the survey areas. (units). Taxonomic classes are concepts. Each taxonomic class has a set of soil characteristics with precisely defined limits. The classes are used as a basis for comparison to classify soils systematically. Soil taxonomy, the system of Survey Procedures taxonomic classification used in the United States, is based mainly on the .kind and character of soil properties and the The general procedures followed in making this survey arrangement of horizons within the profile. After the soil are described in the National Soils Handbook of the Soil scientists classified and named the soils in the survey area, Conservation Service. References that were used in the they compared the individual soils with similar soils in the development of the survey were the "Interim Soil Survey same taxonomic class in other areas so that they could Report, Jackson Area, Oregon," published in 1969 (25); confirm data and assemble additional data based on mapping of the geomorphic surfaces in the valleys of the experience and research. Rogue River and Bear Creek by Parsons (unpublished); While a soil survey is in progress, samples of some of the geologic maps of the Medford Quadrangle, published by the soils in the area generally are collected for laboratory U.S. Geological Survey (USGS) in 1956 and 1982 (30, 21); analyses and for engineering tests. Soil scientists interpret and the memorandum of understanding between the Soil the data from these analyses and tests as well as the Conservation Service and the Bureau of Land Management, field-observed characteristics and the soil properties to the Oregon Agricultural Experiment Station, and the Forest determine the expected behavior of the soils under different Service. uses. Interpretations for all of Hillslopes and relief gradients generally were determined through examination of contour intervals on topographic maps. Cultural features and drainageways were recorded from field observations and through The minimum size of the delineations was mainly about 40 examination of USGS 71/2- and 15-minute topographic acres, but the delineations are as small as 10 acres in maps. areas that are considered to be of extreme importance. The soils in the survey area were mapped according to About 80 percent of the survey area was mapped at the predictable soil patterns that occur on landforms. The lower level of intensity. general soil-landform relationships are described in detail in Spot symbols are used on the maps to identify the section "Formation of the Soils." Traverses and contrasting kinds of soil and miscellaneous areas that are transects were used to confirm soil-landform models that less than 5 acres in size. Under the heading "Detailed Soil were established for various parts of the survey area. Map Units," contrasting soils or miscellaneous areas that Traverses across the landscape were made so that soil are included in mapping are described if they are of scientists could determine the delineations of the map units significant extent in a map unit. and supplement and verify conclusions based on an The soil mapping in the valleys of the Rogue River and examination of the tonal patterns on the aerial photographs Bear Creek and in some adjacent areas is a revision of the used to predict the occurrence of different kinds of soil. The mapping in the survey of the Jackson County area traverses were made by truck and on foot. The soil was published in 1969 (25). Since that time more has been examined when changes in characteristics were apparent. learned about the soils through laboratory analyses and Where the soils vary considerably, many traverses were through examination of data on crop yields and timber site made at short intervals. productivity. Previous concepts have been revised because Transects were made randomly across areas of the map of this improved understanding. units so that the soil scientists could determine the Samples for chemical and physical analyses were taken composition of the dominant and included soils. The soil from typical pedons of the major soils in the survey area. scientists generally crossed the areas on foot, following a The analyses were made by the Soil Survey Laboratory in course that had been charted on aerial photographs. The Lincoln, Nebraska, and by the laboratory at Oregon State soil characteristics were examined and documented at University. The results of the analyses were used in regular intervals. classifying the soils, in determining their fertility and The survey area was mapped at two levels of intensity. erodibility, and in making various interpretations for A higher level was used in mapping alluvial soils and soils engineering, agricultural, and other land uses. on low foothills, which are under intensive agricultural or Soil-plant relationships were evaluated in the community development. Maps of flood plains published development of the detailed map unit descriptions included by the Federal Emergency Management Agency were in this survey. Foresters and range conservationists used as an aid in determining the boundaries of the flood assisted in measuring the potential for timber production at plains. The minimum size of map unit delineations was 5 representative forested sites. Soil and range acres. About 20 percent of the survey area was mapped at conservationists assisted in collecting crop and forage yield this level. data on farms and in areas of rangeland and in determining A lower level of intensity was used in mapping gently the potential productivity of the soils. The data were then sloping to steep soils on uplands. These soils formed in correlated with the kind of soil and the site characteristics of various kinds of parent material. They are used for timber the map units. The results were used to predict the production, livestock grazing, or wildlife habitat. performance of the various map units in the survey area. General Soil Map Units

The general soil map at the back of this publication generally are 0 to 20 percent. Elevation is 1,000 to 4,000 shows broad areas that have a distinctive pattern of soils, feet. The mean annual precipitation is about 18 to 40 relief, and drainage. Each map unit on the general soil map inches, the mean annual temperature is 50 to 54 degrees F, is a unique natural landscape. Typically, it consists of one or and the average frost-free period is 125 to 180 days. more major soils or miscellaneous areas and some minor This unit makes up about 6 percent of the survey area. It soils or miscellaneous areas. It is named for the major soils is about 25 percent Ruch soils, 20 percent Medford soils, or miscellaneous areas. The soils or miscellaneous areas and 10 percent Camas soils (fig. 2). The remaining 45 making up one unit can occur in another but in a different percent is Barron, Central Point, Newberg, Evans, Foehlin, pattern. Kerby, Shefflein, Takilma, Abin, Coleman, Clawson, Kubli, The general soil map can be used to compare the Cove, and Gregory soils and Dumps and Riverwash. Abin, suitability of large areas for general land uses. Areas of Cove, Evans, and Newberg soils and Riverwash are on suitable soils or miscellaneous areas can be identified on flood plains. Central Point, Coleman, Foehlin, Gregory, the map. Likewise, areas that are not suitable can be Kerby, Kubli, and Takilma soils are on stream terraces. identified. Barron, Clawson, and Shefflein soils are on alluvial fans. Because of its small scale, the map is not suitable for They formed in material derived from granitic rock. Dumps planning the management of a farm or field or for selecting a are in areas that have been mined. site for a road or building or other structure. The soils in any Ruch soils are on alluvial fans and are well drained. one map unit differ from place to place in slope, depth, The surface layer is gravelly silt loam. The subsoil is loam. drainage, and other characteristics that affect management. Medford soils are on stream terraces and are The general map units in this survey have been moderately well drained. The surface layer is silty clay grouped for broad interpretive purposes. Each of the loam. The subsoil is silty clay, silty clay loam, and clay broad groups and the map units in each group are loam. The substratum is sandy clay loam. described on the following pages. Camas soils are on flood plains and are excessively drained. The surface layer is sandy loam. The substratum is very gravelly loamy sand and extremely gravelly coarse Map Unit Descriptions sand. These soils are frequently flooded. This unit is used mainly for cultivated crops, hay and Soils Formed in Alluvium on Flood Plains, Stream pasture, tree fruit, or homesite development. A few areas Terraces, and Alluvial Fans are used for timber production or wildlife habitat. These soils make up about 6 percent of the survey This unit is well suited to crops. The main limitations area. affecting crop production are permeability, wetness in winter and spring, flooding, and seasonal droughtiness. In 1. Ruch-Medford-Camas summer, irrigation is needed for the maximum production of most crops. Sprinkler and trickle irrigation systems are Very deep, well drained, moderately well drained, and the best methods of applying water, particularly on the excessively drained soils that have a surface layer of sloping parts of the landscape and on soils that have a gravelly silt loam, silty clay loam, or sandy loam rapid water intake rate. Unless protected, the Camas soils This map unit is on the flood plains, stream terraces, are poorly suited to crops, hay and pasture, and tree fruit and alluvial fans along the Applegate River, Bear Creek, because of the risk of the Rogue River, and their tributaries. The vegetation in areas that have not been cultivated is mainly hardwoods or hardwoods and conifers and an understory of grasses, shrubs, and forbs. Slopes Figure 2.-Typical pattern of soils in the Ruch-Medford-Camas, Tallowbox-Shefflein, and Vannoy-Caris- Offenbacher general map units.

flooding. A subsurface drainage system can lower the is mainly grasses, forbs, and shrubs. That on the Winlo soils water table in the Medford soils if suitable outlets are is mainly grasses, sedges, rushes, and forbs. That on the available. Provig soils is mainly hardwoods and an understory of The main limitations affecting homesite development are grasses, shrubs, and forbs. Slopes generally are 0 to 15 moderately slow permeability, wetness, and the percent but range to 35 percent. Elevation is 1,100 to 1,850 shrink-swell potential in areas of the Medford soils and the feet. The mean annual precipitation is about 18 to 30 hazard of flooding and very rapid permeability in areas of inches, the mean annual temperature is 52 to 54 degrees F, the Camas soils. The Ruch soils have few limitations. and the average frost-free period is 150 to 180 days. This unit makes up about 2 percent of the survey area. It Soils Formed in Material Weathered From is about 45 percent Agate soils, 25 percent Winlo soils, and Sedimentary and Igneous Rock and Mixed Alluvium 10 percent Provig soils. The remaining 20 percent is Brader on Fan Terraces, Ridges, Knolls, Hillslopes, and and Debenger soils on low knolls; Abin, Medford, and Cove Alluvial Fans soils in drainageways; Coker and Padigan soils on concave These soils make up about 10 percent of the survey slopes; and Carney soils. area. Agate, Winlo, and Provig soils formed in poorly sorted, gravelly old stream alluvium. Agate soils are moderately deep to a hardpan and are 2. Agate -Winlo-Provig well drained. The surface layer is loam. The subsoil is clay loam over a hardpan. The substratum is extremely gravelly Well drained and somewhat poorly drained soils that are coarse sandy loam. moderately deep or shallow to a hardpan or are very deep Winlo soils are shallow to a hardpan and are and that have a surface layer of loam, very gravelly clay somewhat poorly drained. The surface layer is very loam, or very gravelly loam; on fan terraces gravelly clay loam. The subsoil is very gravelly clay This map unit is on fan terraces in the valley of the Rogue River. The native vegetation on the Agate soils over a hardpan. The substratum is extremely gravelly in colluvium and alluvium derived from sedimentary coarse sandy loam. rock. Provig soils are very deep and well drained. The surface Brader soils are shallow and well drained. The layer is very gravelly loam. The subsoil is very gravelly clay surface layer and subsoil are loam. loam. The substratum is extremely gravelly clay, extremely Debenger soils are moderately deep and well drained. gravelly clay loam, and extremely gravelly sandy loam. The surface layer is loam. The subsoil is clay loam. This unit is used mainly for hay and pasture, Langellain soils are moderately deep and moderately homesite development, livestock grazing, or wildlife well drained. The surface layer is loam. The subsoil is clay. habitat. This unit is used mainly for hay and pasture or for The main limitations in the areas used for hay and livestock grazing. A few areas are used for homesite pasture or for livestock grazing are wetness in winter and development or wildlife habitat. spring, droughtiness in summer and fall, compaction, the The main limitations in the areas used for hay and depth to a hardpan in the Agate and Winlo soils, and the pasture or for livestock grazing are wetness in winter and very gravelly surface layer in the Winlo and Provig soils. spring, the depth to bedrock, restricted permeability, The Winlo soils remain wet for long periods in spring. If droughtiness, and compaction. The slope also is a major possible, grazing should be delayed until the soils are firm limitation in some areas. The Langellain soils remain wet for enough to withstand trampling by livestock. The use of long periods in spring. Grazing should be delayed until the ground equipment is limited in many areas by gravel and soils are firm enough to withstand trampling by livestock. In cobbles on the surface of the Winlo soils. In summer, summer, irrigation is needed for maximum forage irrigation is needed for maximum forage production. production. Because of the layer of clay in the Langellain Because of the hardpan, overirrigation can result in a soils and the depth to bedrock in the Brader soils, perched water table. overirrigation can result in a perched water table. The main limitations affecting homesite development are The main limitations affecting homesite development are wetness, the depth to a hardpan, slow permeability, and a wetness, a high shrink -swell potential, and the depth to high shrink -swell potential. The slope also is a major bedrock. The slope also is a major limitation in some areas. limitation in some areas. These soils are poorly suited to standard systems of onsite waste disposal because of wetness and the depth to a hardpan in the Winlo soils, the depth to a hardpan in the Agate-soils, and slow permeability of the Provig soils. 4. Carney-Coker

Moderately deep and very deep, moderately well drained 3. Brader-Debenger-Langellain and somewhat poorly drained soils that have a surface layer of clay or cobbly clay; on alluvial fans and hillslopes Shallow and moderately deep, well drained and moderately The native vegetation on the Carney soils in this map unit well drained soils that have a surface layer of loam; on is mainly scattered hardwoods and an understory of ridges and knolls grasses, shrubs, and forbs. That on the Coker soils is mainly The native vegetation on this map unit is mainly grasses, sedges, and forbs. Slopes generally are 0 to 35 hardwoods and some conifers and an understory of percent. Elevation is 1,200 to 4,000 feet. The mean annual grasses, shrubs, and forbs. Slopes generally are 1 to 40 precipitation is about 18 to 35 inches, the mean annual percent. Elevation is 1,000 to 3,500 feet. The mean annual temperature is 45 to 54 degrees F, and the average precipitation is about 18 to 40 inches, the mean annual frost-free period is 120 to 180 days. temperature is 48 to 54 degrees F, and the average This unit makes up about 6 percent of the survey area„ It frost-free period is 130 to 180 days. is about 55 percent Carney soils and 10 percent Coker soils. This unit makes up about 2 percent of the survey area. The remaining 35 percent is Brader and Debenger soils on It is about 35 percent Brader soils, 20 percent Debenger knolls; Heppsie and McMullin soils on hillslopes; Padigan soils, and 15 percent Langellain soils. The remaining 30 and Phoenix soils on concave slopes; Cove soils in percent is Shefflein soils on alluvial fans; Kerby, Medford, drainageways; and Darow, Medco, and Tablerock soils. arid Gregory soils on stream terraces; and Carney, Carney soils formed in alluvium and colluvium derived Selmac, and Coker soils on concave slopes. from igneous rock. Coker soils formed in clayey alluvium Brader and Debenger soils formed in colluvium derived derived from igneous rock. from sedimentary rock. Langellain soils formed Carney soils are moderately deep and moderately well drained. The surface layer is clay or cobbly clay. forbs. Slopes generally are 2 to 70 percent. Elevation is The subsoil is clay. 1,000 to 4,000 feet. The mean annual precipitation is about Coker soils are very deep and somewhat poorly 25 to 40 inches, the mean annual temperature is 46 to 54 drained. The surface layer and subsoil are clay. degrees F, and the average frost-free period is 100 to 160 This unit is used mainly for tree fruit, hay and pasture, days. homesite development, livestock grazing, or wildlife This unit makes up about 3 percent of the survey habitat. area. It is about 55 percent Tallowbox soils and 30 The main limitations in the areas used for hay and percent Shefflein soils (fig. 2). The remaining 15 percent pasture or for tree fruit are the high content of clay, a slow is Barron soils on alluvial fans, Clawson soils on concave rate of water intake, wetness in winter and spring, slopes, and Rogue soils at elevations of more than 4,000 droughtiness in summer and fall, and the slope. The Coker feet. soils remain wet for long periods in spring. Grazing should Tallowbox soils are moderately deep and somewhat be delayed until the soils are firm enough to withstand excessively drained. The surface layer and subsoil are trampling by livestock. In summer, irrigation is needed for gravelly sandy loam. the maximum production of forage crops and tree fruit. Shefflein soils are deep and well drained. The Because of very slow permeability, water applications surface layer is loam. The subsoil is clay loam and should be regulated so that the water does not stand on the sandy clay loam. surface and damage the crops. Because of the slope in 'This unit is used mainly for timber production or wildlife some areas, sprinkler and trickle irrigation systems are the habitat. A few of the more gently sloping areas of the best methods of applying water. The high content of clay Shefflein soils are used for hay and pasture or for homesite severely limits tillage. The soils are well suited to permanent development. pasture. The main limitations affecting timber production are The main limitations affecting homesite development are erosion, compaction, plant competition, and the slope. very slow permeability, a high shrink-swell potential, the Seedling mortality also is a major management concern, depth to bedrock, low strength, and wetness. The slope also particularly on south-facing slopes. Management that is a major limitation in some areas. These soils are poorly minimizes erosion is essential when timber is harvested. suited to standard systems of onsite waste disposal Site preparation is needed to ensure adequate reforestation. because of the very slow permeability and depth to bedrock High-lead or other cable logging systems should be used on in the Carney soils and the very slow permeability and the steeper slopes. wetness in the Coker soils. Properly designing the Irrigation is needed in the areas used for hay and foundations and footings of buildings helps to prevent the pasture. Sprinkler irrigation is the best method of applying structural damage caused by shrinking and swelling. water. This method helps to prevent excessive runoff and The more sloping areas of this unit are used for livestock minimizes the risk of erosion. grazing. The main limitations affecting livestock grazing are The Shefflein soils are well suited to homesite compaction, erosion, droughtiness, and the slope. development. The main limitation is moderately slow permeability. 6. Wolfpeak-Tethrick-Siskiyou

Very deep and moderately deep, well drained and Soils Formed in Material Weathered From Granodiorite somewhat excessively drained soils that have a surface on Alluvial Fans, Ridges, and Hillslopes. layer of sandy loam or gravelly sandy loam and receive 40 These soils make up about 5 percent of the survey to 50 inches of annual precipitation area. This map unit is on hillslopes, ridges, and old slump benches. The native vegetation is mainly conifers and 5. Tallowbox -Shefflein hardwoods and an understory of grasses, shrubs, and forbs. Slopes generally are 3 to 75 percent. Elevation is Moderately deep and deep, somewhat excessively drained 1,200 to 4,000 feet. The mean annual precipitation is about and well drained soils that have a surface layer of gravelly 40 to 50 inches, the mean annual temperature is 45 to 52 sandy loam or loam and receive 25 to 40 inches of annual degrees F, and the average frost-free period is 100 to 160 precipitation days. This map unit is on hillslopes, ridges, and alluvial fans. This unit makes up about 1 percent of the survey area. The native vegetation is mainly conifers and hardwoods It is about 25 percent Wolfpeak soils, 25 percent Tethrick and an understory of grasses, shrubs, and soils, and 25 percent Siskiyou soils. The remaining 25 percent is Beekman and Colestine soils on excessively drained. The surface layer and subsoil are steep hillslopes; Josephine and Pollard soils on gently sandy loam. sloping hillslopes and on concave slopes; and Goolaway, Lettia soils are deep and well drained. The surface layer Musty, and Speaker soils. is sandy loam. The subsoil is clay loam and loam. The Wolfpeak soils are very deep and well drained. The substratum is loam. surface layer is sandy loam. The subsoil is clay loam. This unit is used mainly for timber production or wildlife Tethrick soils are very deep and well drained. The habitat. The main limitations affecting timber production are surface layer, subsoil, and substratum are sandy loam. erosion, compaction, plant competition, and the slope. Siskiyou soils are moderately deep and somewhat Seedling mortality also is a major management concern, excessively drained. The surface layer is gravelly sandy particularly on south-facing slopes. Management that loam. The subsoil and substratum are sandy loam. minimizes erosion is essential when timber is harvested. This unit is used mainly for timber production or wildlife Site preparation is needed to ensure adequate habitat. A few of the more gently sloping areas of the reforestation. High-lead or other cable logging systems Wolfpeak soils are used for hay and pasture or for should be used on the steeper slopes. homesite development. The main limitations affecting timber production are Soils Formed in Material Weathered From Igneous erosion, compaction, plant competition, and the slope. Rock on Plateaus and Hillslopes Seedling mortality also is a major management concern, These soils make up about 40 percent of the survey particularly on south-facing slopes. Management that area. minimizes erosion is essential when timber is harvested. Site preparation is needed to ensure adequate reforestation. 8. Freezener-Geppert High-lead or other cable logging systems should be used on the steeper slopes. Very deep and moderately deep, well drained soils that have Irrigation is needed in the areas used for hay and a surface layer of gravelly loam or very cobbly loam pasture. Sprinkler irrigation is the best method of applying water. This method helps to prevent excessive runoff and This map unit is on plateaus and hillslopes. The native minimizes the risk of erosion. vegetation is mainly conifers and hardwoods and an The Wolfpeak soils are well suited to homesite understory of grasses, shrubs, and forbs. Slopes generally development. The main limitation is moderately slow are 1 to 70 percent. Elevation is 1,500 to 4,000 feet. The permeability. mean annual precipitation is about 30 to 50 inches, the mean annual temperature is 45 to 52 degrees F, and the 7. Steinmetz-Lettia average frost-free period is 100 to 160 days. This unit makes up about 5 percent of the survey Very deep and deep, somewhat excessively drained and area. It is about 65 percent Freezener soils and 30 well drained soils that have a surface layer of sandy loam percent Geppert soils. The remaining 5 percent is and receive 45 to 60 inches of precipitation McMullin soils on ridges and steep hillslopes and This map unit is on hillslopes and old slump benches. Terrabella soils on concave slopes and near The native vegetation is mainly conifers and hardwoods and drainageways. an understory of grasses, shrubs, and forbs. Slopes Freezener soils are very deep. The surface layer is generally are 12 to 75 percent. Elevation is 1,800 to 4,000 gravelly loam. The subsoil is clay loam and clay. feet. The mean annual precipitation is about 45 to 60 Geppert soils are moderately deep. The surface layer is inches, the mean annual temperature is 45 to 50 degrees F, very cobbly loam. The subsoil is extremely cobbly clay loam. and the average frost-free period is 100 to 160 days. This unit is used mainly for timber production, This unit makes up about 1 percent of the survey area. It livestock grazing, or wildlife habitat. A few areas are is about 50 percent Steinmetz soils and 25 percent Lettia used for hay and pasture. soils (fig. 3). The remaining 25 percent is Acker and The main limitations affecting timber production are Dumont soils on gently sloping hillslopes and on concave erosion, compaction, plant competition, and the slope. slopes; Atring and Kanid soils on steep hillslopes; Seedling mortality also is a major management concern, Dubakella, Gravecreek, and Pearsoll soils, which formed in particularly on south-facing slopes. Site preparation is material derived from serpentinitic rock; Goolaway, Musty, needed to ensure adequate reforestation. The large number and Norling soils; and Rogue soils at elevations of more of rock fragments in the Geppert soils increases the seedling than 4,000 feet. mortality rate. High-lead or other cable Steinmetz soils are very deep and somewhat logging systems should be used on the steeper slopes. steep hillslopes, Takilma soils in drainageways, Geppert The main limitations affecting livestock grazing are and McNull soils, Medco soils on gently sloping hillslopes compaction, erosion, and the slope. The slope limits and on concave slopes, and Terrabella soils on concave access by livestock in some areas. slopes and near drainageways. Straight soils are moderately deep. The surface layer is 9. Straight-Freezener-Shippa extremely gravelly loam. The subsoil is very gravelly loam and very cobbly clay loam. Moderately deep, very deep, and shallow, well drained soils Freezener soils are very deep. The surface layer is that have a surface layer of extremely gravelly loam or gravelly loam. The subsoil is clay loam and clay. gravelly loam Shippa soils are shallow. The surface layer is This map unit is on hillslopes and plateaus. The native extremely gravelly loam. The subsoil is extremely vegetation is mainly conifers and hardwoods and an cobbly loam. understory of grasses, shrubs, and forbs. Slopes generally This unit is used mainly for timber production, are 1 to 70 percent. Elevation is 2,000 to 4,000 feet. The livestock grazing, or wildlife habitat. mean annual precipitation is about 35 to 55 inches, the The main limitations affecting timber production are mean annual temperature is 45 to 52 degrees F, and the erosion, compaction, plant competition, the slope, and the average frost-free period is 100 to 160 days. depth to bedrock in the Shippa soils. Seedling mortality This unit makes up about 4 percent of the survey also is a major management concern, particularly on area. It is about 30 percent Straight soils, 25 percent south-facing slopes. Site preparation is needed to Freezener soils, and 10 percent Shippa soils. The ensure-optimum reforestation. The large number of rock remaining 35 percent is McMullin soils on ridges and fragments in the soils and the depth to bedrock in the Shippa soils increase the seedling

Figure 3.-Typical pattern of soils in the Steinmetz-Lettia and Josephine -Beekman-Speaker general map units . mortality rate. High-lead or other cable logging systems grasses, shrubs, and forbs. Slopes generally are 3 to 60 should be used on the steeper slopes. Windthrow is a percent. Elevation is 1,500 to 4,000 feet. The mean annual hazard on the Shippa soils because of the limited depth to precipitation is about 20 to 35 inches, the mean annual bedrock, which restricts the rooting depth. temperature is 45 to 52 degrees F, and the average The main limitations affecting livestock grazing are frost-free period is 100 to 160 days. compaction, erosion, and the slope. The slope limits This unit makes up about 8 percent of the survey area. It access by livestock in some areas. is about 40 percent Medco soils and 35 percent McMullin soils. The remaining 25 percent is Heppsie soils on steep 10. Dumont-Coyata hillslopes, McNull and Carney soils, Coker soils on concave Very deep and moderately deep, well drained soils that slopes, and Rock outcrop. have a surface layer of gravelly loam Medco soils are moderately deep and moderately well This map unit is on plateaus and hillslopes. The native drained. The surface layer is cobbly clay loam. The subsoil vegetation is mainly conifers and hardwoods and an is clay. understory of grasses, shrubs, and forbs. Slopes generally McMullin soils are shallow and well drained. The are 1 to 80 percent. Elevation is 2,000 to 4,000 feet. The surface layer is gravelly loam. The subsoil is gravelly mean annual precipitation is about 40 to 50 inches, the clay loam. mean annual temperature is 45 to 52 degrees F, and the This unit is used mainly for livestock grazing or wildlife average frost-free period is 100 to 160 days. habitat. A few of the more gently sloping areas of the This unit makes up about 3 percent of the survey area. Medco soils are used for hay and pasture. A few areas of It is about 40 percent Dumont soils and 30 percent the Medco soils that receive enough precipitation are used Coyata soils. The remaining 30 percent is Reinecke soils for timber production. on nearly level plateaus, Donegan and Killet soils at The main limitations affecting livestock grazing are elevations of more than 4,000 feet, and Sibannac and compaction, erosion, the depth to bedrock, droughtiness, Terrabella soils on concave slopes and near seasonal wetness, the Rock outcrop, stones and cobbles drainageways. on the surface, and the slope. The use of ground Dumont soils are very deep. The surface layer is equipment generally is not practical on the McMullin soils gravelly loam. The subsoil is clay. because of the stones on the surface, the Rock outcrop, Coyata soils are moderately deep. The surface layer is and the slope. The Rock outcrop and the slope also limit gravelly loam. The subsoil is very cobbly and extremely access by livestock in some areas. The Medco soils cobbly clay loam. remain wet for long periods in spring. Grazing should be This unit is used mainly for timber production, delayed until the soils are firm enough to withstand livestock grazing, or wildlife habitat. trampling by livestock. The main limitations affecting timber production are The main limitations in the areas used for hay and erosion, compaction, plant competition, and the slope. pasture are wetness in winter and spring, droughtiness in Seedling mortality also is a major management concern, summer and fall, and very slow permeability in the subsoil. particularly on south-facing slopes. Site preparation is In summer, irrigation is needed for maximum forage needed to ensure adequate reforestation. The large number production. of rock fragments in the Coyata soils increases the seedling The main limitations affecting timber production are mortality rate. High-lead or other cable logging systems erosion, compaction, slumping, seasonal wetness, and should be used on the steeper slopes. plant competition. Seedling mortality also is a major The main limitations affecting livestock grazing are management concern, particularly on south-facing slopes. compaction, erosion, and the slope. The slope limits access by livestock in some areas. 12. Skookum-McMullin-Rock outcrop 11. Medco-McMullin Rock outcrop and moderately deep and shallow, well Moderately deep and shallow, moderately well drained and drained soils that have a surface layer of very cobbly well drained soils that have a surface layer of cobbly clay loam or gravelly loam loam or gravelly loam This map unit is on hillslopes and plateaus. The native This map unit is on hillslopes. The native vegetation on vegetation on the Skookum soils is mainly hardwoods, the Medco soils is mainly hardwoods, a few scattered scattered conifers, and an understory of grasses, shrubs, conifers, and an understory of grasses, shrubs, and forbs. and forbs. That on the McMullin soils is mainly grasses, That on the McMullin soils is mainly shrubs, and forbs. Slopes generally are 1 to 70 percent. Elevation is 2,800 to 4,800 feet. The surface layer is gravelly loam. The subsoil is gravelly mean annual precipitation is about 18 to 35 inches, the clay loam. mean annual temperature is 45 to 52 degrees F, and the Medco soils are moderately deep and moderately well average frost-free period is 100 to 150 days. drained. The surface layer is cobbly clay loam. The subsoil This unit makes up about 1 percent of the survey area. is clay. It is about 35 percent Skookum soils, 20 percent McMullin This unit is used mainly for timber production, soils, and 20 percent Rock outcrop. The remaining 25 livestock grazing, or wildlife habitat. The McNull and percent is Bogus soils on forested, north-facing slopes; Medco soils are used mainly for timber production or Shoat soils on mounds in areas of patterned ground; livestock grazing. The McMullin soils are used for Randcore soils between the mounds in areas of patterned livestock grazing. ground; Carney soils on concave slopes; and Heppsie and The main limitations affecting timber production are Lorella soils. erosion, compaction, slumping, plant competition, Skookum soils are moderately deep. The surface layer seasonal wetness, and the slope. Seedling mortality also is very cobbly loam. The subsoil is very cobbly clay loam, is a major management concern, particularly on very cobbly clay, and extremely cobbly clay. south-facing slopes. Site preparation is needed to ensure McMullin soils are shallow. The surface layer is adequate reforestation. The Medco soils are subject to gravelly loam. The subsoil is gravelly clay loam. slumping. Road failure and landslides are likely to occur Rock outcrop consists of areas of exposed bedrock. after road construction or clearcutting. The seasonal water This unit is used mainly for livestock grazing or wildlife table in the Medco soils restricts the use of equipment. habitat. The main limitations affecting livestock grazing are High-lead or other cable logging systems should be used compaction, erosion, the Rock outcrop, cobbles and stones on the steeper slopes. on the surface, droughtiness, the depth to bedrock, and the The main limitations affecting livestock grazing are slope. The use of ground equipment is not practical compaction, erosion, the depth to bedrock, droughtiness, because of the cobbles and stones on the surface, the the Rock outcrop, stones and cobbles on the surface, Rock outcrop, and the slope. The Rock outcrop and the seasonal wetness, and the slope. The use of ground slope also limit access by livestock in some areas. The equipment generally is not practical on the McMullin soils suitability of this unit for range seeding is limited by the because of the stones on the surface, the Rock outcrop, depth to bedrock in the McMullin soils, droughtiness, and and the slope. The Rock outcrop and the slope also limit the Rock outcrop. access by livestock in some areas. The Medco soils remain wet for long periods in spring. Grazing should be delayed 13. McNull-McMullin-Medco until the soils are firm enough to withstand trampling by livestock. Moderately deep and shallow, well drained and moderately 14. Tatouche -Bybee well drained soils that have a surface layer of loam, gravelly loam, or cobbly clay loam Very deep, well drained and somewhat poorly drained The map unit is on hillslopes. The native vegetation on soils that have a surface layer of gravelly loam or loam the McNull and Medco soils is mainly conifers and This map unit is on hillslopes and plateaus. The native hardwoods and an understory of grasses, shrubs, and vegetation is mainly conifers and an understory of grasses, forbs. That on the McMullin soils is mainly grasses, shrubs, shrubs, and forbs. Slopes generally are 1 to 65 percent. and forbs. Slopes generally are 12 to 60 percent. Elevation Elevation is 3,600 to 5,500 feet. The mean annual is 1,500 to 4,000 feet. The mean annual precipitation is precipitation is about 30 to 50 inches, the mean annual about 25 to 40 inches, the mean annual temperature is 45 temperature is 40 to 45 degrees F, and the average to 52 degrees F, and the average frost-free period is 100 to frost-free period is less than 100 days. 160 days. This unit makes up about 3 percent of the survey area. It This unit makes up about 8 percent of the survey area. It is about 45 percent Tatouche soils and 30 percent Bybee is about 45 percent McNull soils, 20 percent McMullin soils, soils. The remaining 25 percent is Farva, Hobit, and and 20 percent Medco soils. The remaining 15 percent is Pinehurst soils; Woodseye soils on ridges and convex Coker soils on concave slopes, Carney soils, and Rock slopes; Kanutchan and Sibannac soils on concave slopes outcrop. and near drainageways; and Rock outcrop. McNull soils are moderately deep and well drained. The Tatouche soils are well drained. The surface layer is surface layer is loam. The subsoil is clay loam and cobbly gravelly loam. The subsoil is gravelly clay loam and clay. clay. McMullin soils are shallow and well drained. The Bybee soils are somewhat poorly drained. The surface rock fragments in the soils increases the seedling mortality layer is loam. The subsoil and substratum are clay. rate. Air drainage is restricted in some areas. Proper timber This unit is used mainly for timber production, harvesting methods can reduce the effects of frost on livestock grazing, or wildlife habitat. regeneration. High-lead or other cable logging systems The main limitations affecting timber production are should be used on the steeper slopes. erosion, compaction, slumping, plant competition, The main limitations affecting livestock grazing are seasonal wetness, and the slope. Seedling mortality also compaction, erosion, and the slope. The slope limits is a major management concern, particularly on access by livestock in some areas. south-facing slopes and in areas where air drainage is restricted. Site preparation is needed to ensure adequate 16. Rustlerpeak-Farva reforestation. Air drainage is restricted in some areas. Proper timber harvesting methods can reduce the effects Moderately deep, well drained soils that have a surface of frost on regeneration: The Bybee soils are subject to layer of gravelly loam or very cobbly loam slumping. Road failure and landslides are likely to occur This map unit is on plateaus and hillslopes. The native on these soils after road construction or clearcutting. The vegetation is mainly conifers and an understory of grasses, seasonal high water table in the Bybee soils restricts the shrubs, and forbs. Slopes generally are 3 to 70 percent. use of equipment. High-lead or other cable logging Elevation is 3,600 to 6,100 feet. The mean annual systems should be used on the steeper slopes. precipitation is about 40 to 55 inches, the mean annual The main limitations affecting livestock grazing are temperature is 40 to 45 degrees F, and the average compaction, erosion, and the slope. The slope limits frost-free period is less than 100 days. access by livestock in some areas. This unit makes up about 1 percent of the survey area. It is about 40 percent Rustlerpeak soils and 35 percent Farva soils. The remaining 25 percent is Woodseye soils on ridges and convex slopes; Hobit, 15. Oatman-Otwin Pinehurst, and Snowlin soils; Sibannac soils on concave slopes and near drainageways; and Rock outcrop. Very deep and moderately deep, well drained soils that Rustlerpeak soils have a surface layer of gravelly have a surface layer of cobbly loam or stony sandy loam loam. The subsoil is very cobbly clay loam. This map unit is on plateaus and hillslopes. The native Farva soils have a surface layer of very cobbly loam. vegetation is mainly conifers and an understory of grasses, The subsoil and substratum are extremely cobbly loam. shrubs, and forbs. Slopes generally are 0 to 65 percent. This unit is used mainly for timber production, Elevation is 4,800 to 6,600 feet. The mean annual livestock grazing, or wildlife habitat. precipitation is about 30 to 40 inches, the mean annual The main limitations affecting timber production are temperature is 40 to 44 degrees F, and the average erosion, compaction, plant competition, and the slope. frost-free period is less than 100 days. Seedling mortality also is a major management concern, This unit makes up about 2 percent of the survey area. particularly on south-facing slopes and in areas where air It is about 75 percent Oatman soils and 10 percent Otwin drainage is restricted. Site preparation is needed to ensure soils. The remaining 15 percent is Hoxie and Klamath soils adequate reforestation. The large number of rock fragments on concave slopes and near drainageways. in the soils increases the seedling mortality rate. Air Oatman soils are very deep. The surface layer is drainage is restricted in some areas. Proper timber cobbly loam. The subsoil and substratum are very harvesting methods can reduce the effects of frost on cobbly sandy loam. regeneration. High-lead or other cable logging systems Otwin soils are moderately deep. The surface layer is should be used on the steeper slopes. stony sandy loam. The subsoil is very cobbly sandy loam. The main limitations affecting livestock grazing are This unit is used mainly for timber production, compaction, erosion, and the slope. The slope limits livestock grazing, or wildlife habitat. access by livestock in some areas. The main limitations affecting timber production are erosion, compaction, plant competition, and the slope. 17. Farva -Pinehurst Seedling mortality also is a major management concern, particularly on south-facing slopes and in areas where air Moderately deep and very deep, well drained soils that drainage is restricted. Site preparation is needed to ensure have a surface layer of very cobbly loam or loam adequate reforestation. The large number of This map unit is on plateaus and hillslopes. The native vegetation is mainly conifers and an understory of grasses, shrubs, and forbs. Slopes generally are 3 to 70 percent. Elevation is 3,600 to 5,500 feet. The mean annual precipitation is about 30 to 55 inches, the mean on concave slopes and gently sloping hillslopes; Atring soils annual temperature is 40 to 45 degrees F, and the average on steep hillslopes; Dubakella, Gravecreek, and Pearsoll frost-free period is less than 100 days. soils, which formed in material derived from serpentinitic This unit makes up about 5 percent of the survey area. It rock; Jayar soils at elevations of more than 4,000 feet; and is about 65 percent Farva soils and 20 percent Pinehurst Jayar Variant soils at elevations of more than 4,700 feet. soils. The remaining 15 percent is Woodseye soils on Acker soils are very deep. The surface layer is ridges and convex slopes, Tatouche soils, Bybee and gravelly loam. The subsoil is gravelly clay loam. Kanutchan soils on concave slopes, Sibannac soils on Norling soils are moderately deep. The surface layer is concave slopes and near drainageways, and Rock outcrop. very gravelly loam. The subsoil is gravelly and very cobbly Farva soils are moderately deep. The surface layer is clay loam. very cobbly loam. The subsoil and substratum are extremely Kanid soils are deep. The surface layer is very cobbly loam. gravelly loam. The subsoil is very gravelly clay loam. Pinehurst soils are very deep. The surface layer is This unit is used mainly for timber production or wildlife loam. The subsoil is clay loam. habitat. The main limitations affecting timber production are This unit is used mainly for timber production, erosion, compaction, plant competition, and the slope. livestock grazing, or wildlife habitat. Seedling mortality also is a major management concern, The main limitations affecting timber production are particularly on south-facing slopes. Site preparation is erosion, compaction, plant competition, and the slope. needed to ensure adequate reforestation. The large number Seedling mortality also is a major management concern, of rock fragments in the Kanid soils increases the seedling particularly on south-facing slopes and in areas where air mortality rate. High-lead or other cable logging systems drainage is restricted. Site preparation is needed to ensure should be used on the steeper slopes. adequate reforestation. The large number of rock fragments in the Farva soils increases the seedling mortality rate. Air drainage is restricted in some areas. Proper timber harvesting methods can reduce the effects of frost on 19. Josephine -Beekman-Speaker regeneration. High-lead or other cable logging systems Deep and moderately deep, well drained soils that have a should be used on the steeper slopes. surface layer of gravelly loam or loam The main limitations affecting livestock grazing are This map unit is on hillslopes. The native vegetation is compaction, erosion, and the slope. The slope limits mainly conifers and hardwoods and an understory of access by livestock in some areas. grasses, shrubs, and forbs. Slopes generally are 12 to 80 percent. Elevation is 1,200 to 4,000 feet. The mean annual Soils Formed in Material Weathered From Altered precipitation is about 40 to 50 inches, the mean annual Sedimentary and Igneous Rock on Ridges and temperature is 45 to 52 degrees F, and the average Hillslopes frost-free period is 100 to 160 days. This unit makes up about 5 percent of the survey area. It These soils make up about 23 percent of the survey is about 30 percent Josephine soils, 20 percent Beekman area. soils, and 20 percent Speaker soils (fig. 3). The remaining 18. Acker-Norling-Kanid 30 percent is Camas, Evans, and Newberg soils on flood plains; Abegg and Pollard soils on alluvial fans and concave Very deep, moderately deep, and deep, well drained soils slopes; McMullin soils on ridges and steep hillslopes; that have a surface layer of gravelly loam or very gravelly Dubakella and Pearsoll soils, which formed in material loam derived from serpentinitic rock; and Colestine soils on steep This map unit is on hillslopes. The native vegetation is hillslopes. mainly conifers and hardwoods and an understory of Josephine soils are deep. The surface layer is grasses, shrubs, and forbs. Slopes generally are 12 to 80 gravelly loam. The subsoil is gravelly clay loam. percent. Elevation is 2,400 to 4,100 feet. The mean annual Beekman soils are moderately deep. The surface layer precipitation is about 45 to 60 inches, the mean annual is gravelly loam. The subsoil is extremely gravelly loam. temperature is 45 to 50 degrees F, and the average Speaker soils are moderately deep. The surface frost-free period is 100 to 160 days. layer is loam. The subsoil is loam and gravelly clay This unit makes up about 1 percent of the survey area. It loam. is about 30 percent Acker soils, 20 percent Norling soils, This unit is used mainly for timber production or and 15 percent Kanid soils. The remaining 35 percent is wildlife habitat. The main limitations affecting timber Abegg soils on alluvial fans; Dumont soils production are erosion, compaction, plant competition, and on the Vannoy soils are the depth to bedrock, the slope, the slope. Seedling mortality also is a major management moderately slow permeability, and low strength. concern, particularly on south-facing slopes. Site preparation is needed to ensure adequate reforestation. 21. Goolaway-Beekman-Musty The large number of rock fragments in the Beekman soils Moderately deep, well drained soils that have a surface increases the seedling mortality rate. High-lead or other layer of silt loam or gravelly loam cable logging systems should be used on the steeper This map unit is on ridges and hillsides. The native slopes. vegetation is mainly conifers and hardwoods and an understory of grasses, shrubs, and forbs. Slopes generally 20. Vannoy-Caris-Offenbacher are 12 to 80 percent. Elevation is 1,500 to 4,000 feet. The mean annual precipitation is about 40 to 50 inches, the Moderately deep, well drained soils that have a surface mean annual temperature is 45 to 52 degrees F, and the layer of silt loam or gravelly loam average frost-free period is 100 to 160 days. This map unit is on hillslopes. The native vegetation is This unit makes up about 2 percent of the survey area. mainly conifers and hardwoods and an understory of It is about 25 percent Goolaway soils, 20 percent Beekman grasses, shrubs, and forbs. Slopes generally are 12 to 80 soils, and .10 percent Musty soils. The remaining 45 percent. Elevation is 1,000 to 4,000 feet. The mean annual percent is Colestine soils on steep hillslopes; Pollard and precipitation is about 20 to 40 inches, the mean annual Wolfpeak soils on concave slopes; Josephine, Speaker, temperature is 46 to 54 degrees F, and the average Tethrick, and Steinmetz soils; and Snowbrier soils at frost-free period is 100 to 160 days. elevations of more than 3,600 feet. This unit makes up about 15 percent of the survey area. Goolaway soils have a surface layer and subsoil of silt It is about 35 percent Vannoy soils, 25 percent Caris soils, loam. and 10 percent Offenbacher soils (fig. 2). The remaining 30 Beekman soils have a surface layer of gravelly loam. percent is Camas, Evans, and Newberg soils on flood The subsoil is extremely gravelly loam. plains; Abegg and Ruch soils on alluvial fans; Selmac soils Musty soils have a surface layer of gravelly loam. on concave slopes; Manita and Shefflein soils on alluvial The subsoil is very cobbly loam. fans and gently sloping hillslopes; Dubakella soils, which This unit is used mainly for timber production or wildlife formed in material derived from serpentinitic rock; McMullin habitat. The main limitations affecting timber production are soils on ridges and steep hillslopes; Tallowbox and erosion, compaction, plant competition, and the slope. Voorhies soils; and Jayar soils at elevations of more than Seedling mortality also is a major management concern, 4,000 feet. particularly on south-facing slopes. The hazard of erosion is Vannoy soils have a surface layer of silt loam. The high. Management that minimizes erosion is essential when subsoil is clay loam, gravelly clay loam, and extremely timber is harvested. Site preparation is needed to ensure gravelly clay loam. adequate reforestation. The large number of rock fragments Caris soils have a surface layer of gravelly loam. The in the Beekman and Musty soils increases the seedling subsoil is very gravelly clay loam and extremely gravelly mortality rate. High-lead or other cable logging systems loam. should be used on the steeper slopes. Offenbacher soils have a surface layer of gravelly Soils Formed in Material Weathered From loam. The subsoil is loam. Pyroclastics and Igneous Rock on Plateaus and This unit is used mainly for timber production or wildlife Hillslopes habitat. A few of the more gently sloping areas of the Vannoy soils are used for pasture or homesite development. These soils make up about 16 percent of the survey The main limitations affecting timber production are area. erosion, compaction, plant competition, and the slope. Seedling mortality also is a major management concern, particularly on south-facing slopes. Site preparation is needed to ensure adequate reforestation. The large number 22. Hukill-Geppert of rock fragments in the Caris soils increases the seedling Deep and moderately deep, well drained soils that are mortality rate. High-lead or other cable logging systems gravelly loam in the upper part of the surface layer or should be used on the steeper slopes. have a surface layer of very cobbly loam Irrigation can increase forage production on the This map unit is on plateaus and hillslopes. The native Vannoy soils. The water supply, however, is limited. vegetation is mainly conifers and hardwoods and The main limitations affecting homesite development an understory of grasses, shrubs, and forbs. Slopes surface layer and subsoil are gravelly sandy loam. The generally are 1 to 35 percent but are as much as 70 substratum is very cobbly sandy loam. percent. Elevation is 2,000 to 3,000 feet. The mean annual Barhiskey soils are excessively drained. The surface precipitation is about 30 to 45 inches, the mean annual layer is gravelly loamy sand. The substratum is gravelly temperature is 45 to 52 degrees F, and the average sand. frost-free period is 100 to 160 days. This unit is used mainly for timber production, livestock This unit makes up about 1 percent of the survey area. grazing, or wildlife habitat. A few areas are used for hay It is about 70 percent Hukill soils and 10 percent Geppert and pasture or for homesite development. soils. The remaining 20 percent is Terrabella soils on The main limitations affecting timber production are concave slopes and Freezener soils. compaction, erosion, soil displacement, and plant Hukill soils are deep. The upper part of the surface layer competition. Seedling mortality also is a major management is gravelly loam, and the lower part is gravelly clay loam. concern, particularly on south-facing slopes and in areas The subsoil is gravelly clay loam and gravelly clay. where air drainage is restricted. Site preparation is needed Geppert soils are moderately deep. The surface layer is to ensure adequate reforestation. The sandy texture and low very cobbly loam. The subsoil is extremely cobbly clay available water capacity of the Barhiskey soils increase the loam. seedling mortality rate. Air drainage is restricted in some This unit is used mainly for timber production, areas. Proper timber harvesting methods can reduce the livestock grazing, or wildlife habitat. effects of frost on regeneration. Displacement of the surface The main limitations affecting timber production are layer occurs most readily when the soils are dry. compaction and plant competition on the Hukill soils and Compaction of the Crater Lake and Alcot soils can be erosion, compaction, plant competition, and seedling minimized by using suitable methods of harvesting, laying mortality on the Geppert soils. Site preparation is needed to out skid trails in advance, and harvesting timber when the ensure adequate reforestation. The large number of rock soils are least susceptible to compaction. fragments in the Geppert soils increases the seedling The main limitations affecting livestock grazing are mortality rate. Compaction can be minimized by using compaction, soil displacement, and erosion. suitable methods of harvesting, laying out skid trails in The main limitations affecting homesite development are advance, and harvesting timber when the soils are least very rapid or rapid permeability, a high content of volcanic susceptible to compaction. ash and pumice in the Crater Lake and Alcot soils, and a The main limitation affecting livestock grazing is high content of sand in the Barhiskey soils. compaction. 24. Pokegema-Woodcock 23. Crater Lake -Alcot-Barhiskey Deep and very deep, well drained soils that are loam or Very deep, well drained, somewhat excessively drained, and stony loam in the upper part of the surface layer excessively drained soils that have a surface layer of sandy This map unit is on hillslopes and plateaus. The native loam, gravelly sandy loam, or gravelly loamy sand vegetation is mainly conifers and an understory of grasses, This map unit is on plateaus, hillslopes, and outwash shrubs, and forbs. Slopes generally are 1 to 55 percent. plains. The native vegetation is mainly conifers and Elevation is 3,800 to 6,600 feet. The mean annual hardwoods and an understory of grasses, shrubs, and precipitation is about 25 to 35 inches, the mean annual forbs. Slopes generally are 0 to 35 percent but are as much temperature is 40 to 45 degrees F, and the average as 70 percent. Elevation is 2,000 to 3,200 feet. The mean frost-free period is less than 100 days. annual precipitation is about 40 to 50 inches, the mean This unit makes up about 9 percent of the survey annual temperature is 45 to 50 degrees F, and the average area. It is about 50 percent Pokegema soils and 35 frost-free period is 100 to 150 days. percent Woodcock soils. The remaining 15 percent is This unit makes up about 1 percent of the survey Klamath soils on concave slopes and near drainageways area. It is about 35 percent Crater Lake soils, 20 and Aspenlake and Whiteface soils on alluvial fans. percent Alcot soils, and 20 percent Barhiskey soils (fig. Pokegema soils are deep. The upper part of the 4). The remaining 25 percent is Sibannac soils near surface layer is loam, and the lower part is clay loam. The drainageways and Barhiskey Variant, Coyata, Dumont, subsoil and substratum are gravelly clay. and Reinecke soils. Woodcock soils are very deep. The upper part of the Crater Lake soils are well drained. The surface layer, surface layer is stony loam, and the lower part is very subsoil, and substratum are sandy loam. gravelly loam. The subsoil is very gravelly clay loam. Alcot soils are somewhat excessively drained. The Figure 4.-Typical pattern of soils in the Crater Lake-Alcot-Barhiskey general map unit.

The substratum is gravelly clay loam. some areas. Proper timber harvesting methods can reduce This unit is used mainly for timber production, the effects of frost on regeneration. Compaction can be livestock grazing, or wildlife habitat. minimized by using suitable methods of harvesting, laying The main limitations affecting timber production are out skid trails in advance, and harvesting timber when the erosion, compaction, plant competition, and the slope. soils are least susceptible to compaction. High-lead or other Seedling mortality also is a major management concern, cable logging systems should be used on the steeper particularly on south-facing slopes and in areas where air slopes. drainage is restricted. Site preparation is needed to ensure The main limitations affecting livestock grazing are adequate reforestation. The large number of rock fragments compaction, erosion, and the slope. The slope limits in the Woodcock soils increases the seedling mortality rate. access by livestock in some areas. Air drainage is restricted in 25. Pinehurst-Greystoke-Bly compaction. High-lead or other cable logging systems should be used on the steeper slopes. Very deep and deep, well drained soils that have a surface The main limitations affecting livestock grazing are layer of loam or are stony loam in the upper part of the compaction, erosion, and the slope. The slope limits surface layer access by livestock in some areas. This map unit is on hillsides and plateaus. The native vegetation is mainly conifers and an understory of grasses, 26. Campfour-Paragon shrubs, and forbs. Slopes generally are 1 to 75 percent. Elevation is 3,000 to 5,200 feet. The mean annual Very deep and moderately deep, well drained soils that precipitation is about 15 to 30 inches, the mean annual have a surface layer of loam or cobbly loam temperature is 42 to 46 degrees F, and the average This map unit is on plateaus and hillslopes. The native frost-free period is less than 100 days. vegetation is mainly conifers and hardwoods and an This unit makes up about 4 percent of the survey area. understory of grasses, shrubs, and forbs. Slopes generally It is about 40 percent Pinehurst soils, 25 percent are 1 to 35 percent. Elevation is 3,000 to 4,400 feet. The Greystoke soils, and 10 percent Bly soils. The remaining mean annual precipitation is about 20 to 25 inches, the 25 percent is Kanutchan soils on concave slopes and mean annual temperature is 45 to 51 degrees F, and the Booth, Kanutchan Variant, Lorella, Merlin, and Royst soils. average frost-free period is 100 to 130 days. Pinehurst soils formed in colluvium derived from igneous This unit makes up about 1 percent of the survey rock. Greystoke soils formed in colluvium and residuum area. It is about 35 percent Campfour soils and 30 derived from igneous rock. Bly soils formed in sediment percent Paragon soils. The remaining 35 percent is derived from igneous rock and volcanic ash. Shoat soils on mounds in areas of patterned ground, Pinehurst soils are very deep. The surface layer is Randcore soils between the mounds in areas of loam. The subsoil is clay loam. patterned ground, McMullin soils on ridges and steep Greystoke soils are deep. The upper part of the hillslopes, and Skookum soils. surface layer is stony loam, and the lower part is very Campfour soils are very deep. The surface layer is cobbly loam. The subsoil is very cobbly loam and loam. The subsoil is clay loam and gravelly clay loam. extremely gravelly clay loam. Paragon soils are moderately deep. The surface layer Bly soils are very deep. The surface layer is loam. is cobbly loam. The subsoil is gravelly clay loam. The subsoil is clay loam. This unit is used mainly for timber production, This unit is used mainly for timber production, livestock grazing, or wildlife habitat. livestock grazing, or wildlife habitat. The main limitations affecting timber production are The main limitations affecting timber production are compaction and erosion. Seedling mortality also is a major erosion, compaction, plant competition, and the slope. management concern, particularly on south-facing slopes Seedling mortality also is a major management concern, and in areas where air drainage is restricted. The large particularly on south-facing slopes and in areas where air number of rock fragments in the Paragon soils increases the drainage is restricted. Site preparation is needed to ensure seedling mortality rate. Air drainage is restricted in some adequate reforestation. The large number of rock fragments areas. Proper timber harvesting methods can reduce the in the Greystoke soils increases the seedling mortality rate. effects of frost on regeneration. Compaction can be Air drainage is restricted in some areas. Proper timber minimized by using suitable methods of harvesting, laying harvesting methods can reduce the effects of frost on out skid trails in advance, and harvesting timber when the regeneration. Compaction can be minimized by using soils are least susceptible to compaction. suitable methods of harvesting, laying out skid trails in The main limitations affecting livestock grazing are advance, and harvesting timber when the soils are least compaction and erosion. susceptible to Detailed Soil Map Units

The map units delineated on the detailed maps at the unit descriptions. A few included areas may not have been back of this survey represent the soils or miscellaneous observed, and consequently they are not mentioned in the areas in the survey area. The map unit descriptions in this descriptions, especially where the pattern was so complex section, along with the maps, can be used to determine the that it was impractical to make enough observations to suitability and potential of a unit for specific uses. They also identify all the soils and miscellaneous areas on the can be used to plan the management needed for those landscape. uses. More information on each map unit is given under The presence of included areas in a map unit in no way "Use and Management of the Soils." diminishes the usefulness or accuracy of the data. The A map unit delineation on a map represents an area objective of mapping is not to delineate pure taxonomic dominated by one or more major kinds of soil or classes but rather to separate the landscape into segments miscellaneous areas. A map unit is identified and named that have similar use and management requirements. The according to the taxonomic classification of the dominant delineation of such landscape segments on the map soils or miscellaneous areas. Within a taxonomic class there provides sufficient information for the development of are precisely defined limits for the properties of the soils. On resource plans, but if intensive use of small areas is the landscape, however, the soils and miscellaneous areas planned, onsite investigation is needed to define and locate are natural phenomena, and they have the characteristic the soils and miscellaneous areas. variability of all natural phenomena. Thus, the range of An identifying symbol precedes the map unit name in some observed properties may extend beyond the limits the: map unit descriptions. Each description includes defined for a taxonomic class. Areas of soils of a single general facts about the unit and gives the principal hazards taxonomic class rarely, if ever, can be mapped without and limitations to be considered in planning for specific including areas of other taxonomic classes. Consequently, uses. every map unit is made up of the soils or miscellaneous Soils that have profiles that are almost alike make up a areas for which it is named and some "included" areas that soil series. Except for differences in texture of the surface belong to other taxonomic classes. layer or of the underlying layers, all the soils of a series Most included soils have properties similar to those of have major horizons that are similar in composition, the dominant soil or soils in the map unit, and thus they do thickness, and arrangement. not affect use and management. These are called Soils of one series can differ in texture of the surface noncontrasting, or similar, inclusions. They may or may not layer or of the underlying layers. They also can differ in be mentioned in the map unit description. Other included slope, stoniness, acidity, wetness, degree of erosion, and soils and miscellaneous areas, however, have properties other characteristics that affect their use. On the basis of and behavioral characteristics divergent enough to affect such differences, a soil series is divided into soil phases. use or to require different management. These are called Most of the areas shown on the detailed soil maps are contrasting, or dissimilar, inclusions. They generally are in phases of soil series. The name of a soil phase commonly small areas and could not be mapped separately because indicates a feature that affects use or management. For of the scale used. Some small areas of strongly contrasting example, Carney clay, 1 to 5 percent slopes, is a phase of soils or miscellaneous areas are identified by a special the Carney series. symbol on the maps. The included areas of contrasting soils Some map units are made up of two or more major soils or miscellaneous areas are mentioned in the map or miscellaneous areas. These map units are complexes. A complex consists of two or more soils or miscellaneous areas in such an intricate pattern or in such small areas that they cannot be shown separately on the maps. The pattern and proportion of the soils or miscellaneous areas are somewhat similar in all areas. fragments limit the use of equipment and increase Agate-Winlo complex, 0 to 5 percent slopes, is an maintenance costs. example. In summer, irrigation is needed for the maximum This survey includes miscellaneous areas. Such areas production of most forage crops. Sprinkler irrigation is the have little or no soil material and support little or no best method of applying water. This method permits an vegetation. Riverwash is an example. even, controlled application of water, helps to prevent Table 4 gives the acreage and proportionate extent of excessive runoff, and minimizes the risk of erosion. Border each map unit. Other tables (see "Summary of Tables") and contour flood irrigation systems also are suitable. For give properties of the soils and the limitations, capabilities, the efficient application and removal of surface irrigation and potentials for many uses. The "Glossary" defines many water, land leveling is needed. To prevent overirrigation and of the terms used in describing the soils or miscellaneous the leaching of plant nutrients, applications of irrigation areas. water should be adjusted to the available water capacity, the rate of water intake, and the needs of the crop. Because the soil is droughty, the applications should be light and Map Unit Descriptions frequent. The use of pipe, ditch lining, or drop structures in irrigation ditches reduces water loss and the hazard of 1B-Abegg gravelly loam, 2 to 7 percent slopes. erosion. This very deep, well drained soil is on alluvial fans. It Proper stocking rates, pasture rotation, and deferment of formed in alluvium derived dominantly from metamorphic grazing during wet periods help to keep pastures in good rock. Elevation is 1,000 to 2,500 feet. The mean annual condition, minimize compaction, and protect the soil from precipitation is 30 to 40 inches, the mean annual erosion. Grazing when the soil is wet results in compaction temperature is 50 to 54 degrees F, and the average of the surface layer, poor tilth, and excessive runoff. Periodic frost-free period is 140 to 180 days. The native vegetation is mowing and clipping help to maintain uniform plant growth, mainly conifers and hardwoods and an understory of discourage selective grazing, and reduce the extent of grasses, shrubs, and forbs. clumpy growth. Fertilizer is needed to ensure the optimum Typically, the surface is covered with a layer of needles, growth of grasses and legumes. Grasses respond to leaves, and twigs about '/2 inch thick. The surface layer is nitrogen, and legumes respond to sulfur and phosphorus. very dark grayish brown gravelly loam about 5 inches thick. The main limitation affecting homesite development is The next layer is very dark grayish brown and brown very the large number of rock fragments on and below the gravelly loam about 17 inches thick. The upper 16 inches of surface. Cutbanks are not stable and are subject to the subsoil is dark yellowish brown extremely gravelly loam. slumping. To keep cutbanks from caving in, excavations The lower 28 inches is brown and yellowish brown may require special retainer walls. Revegetating as soon as extremely gravelly clay loam. The depth to bedrock is 60 possible helps to control erosion in disturbed areas around inches or more. In some areas the surface layer is cobbly or construction sites. stony. Establishing plants is difficult in areas where the surface Included in this unit are small areas of Xerorthents; layer has been removed and the extremely gravelly subsoil Ruch and Vannoy soils; Camas, Evans, and Newberg soils exposed. Mulching and applying fertilizer help to establish on flood plains; and Takilma soils on terraces. Also plants in cut areas. Gravel and cobbles should be removed included are small areas of soils that are similar to the from disturbed areas, particularly areas used for lawns. Abegg soil but have bedrock at a depth of 40 to 60 inches, Topsoil can be stockpiled and used to reclaim areas poorly drained soils near drainageways, and Abegg soils disturbed during construction. In many areas it may be that have slopes of more than 7 percent. Included areas necessary to haul in topsoil for lawns and gardens. Because make up about 20 percent of the total acreage. of droughtiness and a low amount of rainfall in summer, Permeability is moderate in the Abegg soil. Available irrigation is needed in areas that support lawn grasses, water capacity is about 4 inches. The effective rooting shrubs, vines, shade trees, or ornamental trees. depth is 60 inches or more. Runoff is slow, and the hazard This unit is suited to the production of Douglas fir and of water erosion is slight. ponderosa pine. Other species that grow on this unit This unit is used mainly for hay and pasture. It also is include incense cedar, California black oak, and Pacific used for timber production and homesite development. madrone. The understory vegetation includes Pacific This unit is suited to hay and pasture. It is limited serviceberry, tall Oregongrape, and California fescue. mainly by droughtiness and a large number of rock fragments on and below the surface. The rock On the basis of a 100-year site curve, the mean site average frost-free period is 140 to 180 days. The native index for Douglas-fir is 115. The yield at culmination of the vegetation is mainly conifers and hardwoods and an mean annual increment is 6,360 cubic feet per acre in a understory of grasses, shrubs, and forbs. fully stocked, even-aged stand of trees at 60 years and Typically, the surface is covered with a layer of needles, 50,700 board feet per acre (Scribner rule) at 130 years. On leaves, and twigs about 1/2 inch thick. The surface layer is the basis of a 50-year curve, the mean site index is 90. very dark grayish brown gravelly loam about 5 inches thick. The main limitations affecting timber production are The next layer is very dark grayish brown and brown very compaction, seedling mortality, and plant competition. gravelly loam about 17 inches thick. The upper 16 inches of Conventional methods of harvesting timber generally are the subsoil is dark yellowish brown extremely gravelly loam. suitable, but the soil may be compacted if it is moist when The lower 28 inches is brown and yellowish brown heavy equipment is used. Puddling can occur when the soil extremely gravelly clay loam. The depth to bedrock is 60 is wet. If the soil is excessively disturbed when timber is inches or more. In some areas the surface layer is cobbly or harvested or logging roads are built, a larger number of rock stony. fragments is left on the surface. Using low-pressure ground Included in this unit are small areas of Xerorthents; Ruch equipment causes less damage to the soil and helps to and Vannoy soils; Camas, Evans, and Newberg soils on maintain productivity. Compaction can be minimized by flood plains; and Takilma soils on terraces. Also included using suitable methods of harvesting, laying out skid trails in are small areas of soils that are similar to the Abegg soil but advance, and harvesting timber when the soil is least have bedrock at a depth of 40 to 60 inches, poorly drained susceptible to compaction. Ripping skid trails and landings soils near drainageways, and Abegg soils that have slopes when the soil is dry can improve the growth of plants. of less than 7 or more than 12 percent. Included areas Erosion can be controlled by carefully planning the make up about 20 percent of the total acreage. construction and maintenance of logging roads, skid trails, Permeability is moderate in the Abegg soil. Available and landings. Seeding, mulching, and benching areas that water capacity is about 4 inches. The effective rooting have been cut and filled also help to control erosion. Skid depth is 60 inches or more. Runoff is slow, and the hazard trails and unsurfaced roads may be impassable during of water erosion is slight. rainy periods. Logging roads require suitable surfacing for This unit is used mainly for hay and pasture. It also is year-round use. used for timber production and homesite development. A high temperature in the surface layer during summer This unit is suited to hay and pasture. It is limited and the low available water capacity increase the seedling mainly by the slope, droughtiness, and the large number mortality rate. The large number of rock fragments in the of rock fragments on and below the surface. The rock soil also increases the seedling mortality rate. To fragments limit the use of equipment and increase compensate for the expected high mortality rate, the larger maintenance costs. seedlings or a greater number of seedlings should be In summer, irrigation is needed for the maximum planted. When the timber is harvested, leaving some of the production of most forage crops. Because of the slope, larger trees unharvested provides shade for seedlings. sprinkler irrigation is the best method of applying water. This Reforestation can be accomplished by planting Douglas fir method permits an even, controlled application of water, and ponderosa pine seedlings. helps to prevent excessive runoff, and minimizes the risk of Undesirable plants limit natural or artificial erosion. To prevent overirrigation and excessive erosion, reforestation unless intensive site preparation and applications of irrigation water should be adjusted to the maintenance measures are applied. Mulching around available water capacity, the rate of water intake, and the seedlings helps to maintain the moisture supply in needs of the crop. Because the soil is droughty, the summer and minimizes competition from undesirable applications should be light and frequent. understory plants. Seedbeds should be prepared on the contour or across The vegetative site is Pine-Douglas Fir-Fescue. the slope where practical. Proper stocking rates, pasture rotation, and restricted grazing during wet periods help to 1C-Abegg gravelly loam, 7 to 12 percent slopes. keep pastures in good condition and protect the soil from This very deep, well drained soil is on alluvial fans. It erosion. Grazing when the soil is wet results in compaction formed in alluvium derived dominantly from metamorphic of the surface layer, poor tilth, and excessive runoff. Periodic rock. Elevation is 1,000 to 2,500 feet. The mean annual mowing and clipping help to maintain uniform plant growth, precipitation is 30 to 40 inches, the mean annual discourage selective grazing, and reduce the extent of temperature is 50 to 54 degrees F, and the clumpy growth. Fertilizer is needed to ensure the optimum growth of construction and maintenance of logging roads, skid trails, grasses and legumes. Grasses respond to nitrogen, and and landings. Seeding, mulching, and benching areas that legumes respond to sulfur and phosphorus. have been cut and filled also help to control erosion. Skid The main limitations affecting homesite development are trails and unsurfaced roads may be impassable during the large number of rock fragments on and below the rainy periods. Logging roads require suitable surfacing for surface and the slope. Cutbanks are not stable and are year-round use. subject to slumping. To keep cutbanks from caving in, A high temperature in the surface layer during summer excavations may require special retainer walls. Erosion is a and the low available water capacity increase the seedling hazard on the steeper slopes. Only the part of the site that mortality rate. The large number of rock fragments in the is used for construction should be disturbed. Revegetating soil also increases the seedling mortality rate. To as soon as possible helps to control erosion in disturbed compensate for the expected high mortality rate, the larger areas around construction sites. seedlings or a greater number of seedlings should be Establishing plants is difficult in areas where the surface planted. When the timber is harvested, leaving some of the layer has been removed and the extremely gravelly subsoil larger trees unharvested provides shade for seedlings. exposed. Mulching and applying fertilizer help to establish Reforestation can be accomplished by planting Douglas fir plants in cut areas. Gravel and cobbles should be removed and ponderosa pine seedlings. from disturbed areas, particularly areas used for lawns. Undesirable plants limit natural or artificial Topsoil can be stockpiled and used to reclaim areas reforestation unless intensive site preparation and disturbed during construction. In many areas it may be maintenance measures are applied. Mulching around necessary to haul in topsoil for lawns and gardens. Because seedlings helps to maintain the moisture supply in of droughtiness and a low amount of rainfall in summer, summer and minimizes competition from undesirable irrigation is needed in areas that support lawn grasses, understory plants. shrubs, vines, shade trees, or ornamental trees. The vegetative site is Pine-Douglas Fir-Fescue. This unit is suited to the production of Douglas fir and ponderosa pine. Other species that grow on this unit 2A-Abin silty clay loam, 0 to 3 percent slopes. include incense cedar, California black oak, and Pacific This very deep, moderately well drained soil is on flood madrone. The understory vegetation includes Pacific plains. It formed in alluvium derived from mixed sources. serviceberry, tall Oregongrape, and California fescue. Elevation is 1,000 to 2,500 feet. The mean annual On the basis of a 100-year site curve, the mean site precipitation is 18 to 35 inches, the mean annual index for Douglas fir is 115. The yield at culmination of the temperature is 50 to 54 degrees F, and the average mean annual increment is 6,360 cubic feet per acre in a frost-free period is 140 to 180 days. The native vegetation in fully stocked, even-aged stand of trees at 60 years and areas that have not been cultivated is mainly hardwoods 50,700 board feet per acre (Scribner rule) at 130 years. On and an understory of grasses, shrubs, and forbs. the basis of a 50-year curve, the mean site index is 90. Typically, the surface layer is very dark grayish brown The main limitations affecting timber production are silty clay loam about 34 inches thick. The upper 10 inches of compaction, seedling mortality, and plant competition. the substratum is very dark brown silty clay loam. The lower Conventional methods of harvesting timber generally are part to a depth of 65 inches is very dark grayish brown silty suitable, but the soil may be compacted if, it is moist when clay loam. heavy equipment is used. Puddling can occur when the soil Included in this unit are small areas of Evans, Newberg, is wet. If the soil is excessively disturbed when timber is and Camas soils; Central Point, Gregory, and Medford soils harvested or logging roads are built, a larger number of rock on terraces; and Cove soils on concave slopes. Also fragments is left on the surface. Using low-pressure ground included are small areas of Abin soils that have slopes of equipment causes less damage to the soil and helps to more than 3 percent. Included areas make up about 15 maintain productivity. Compaction can be minimized by percent of the total acreage. using suitable methods of harvesting, laying out skid trails in Permeability is moderately slow in the Abin soil. advance, and harvesting timber when the soil is least Available water capacity is about 11 inches. The effective susceptible to compaction. Ripping skid trails and landings rooting depth is 60 inches or more. Runoff is slow, and the when the soil is dry can improve the growth of plants. hazard of water erosion is slight. The water table Erosion can be controlled by carefully planning the fluctuates between depths of 3 and 5 feet from December through April. This soil is occasionally flooded for brief periods from December through April. This unit is used mainly for irrigated crops, such as alfalfa hay and small grain. Other crops include corn for the hazard of flooding increase the possibility that septic silage and tree fruit. Some areas are used for grass-legume tank absorption fields will fail. The moderately slow hay, pasture, or homesite development. permeability can be overcome by increasing the size of the This unit is suited to irrigated crops. It is limited mainly by absorption field. Interceptor ditches can divert subsurface the hazard of flooding, the moderately slow permeability, water and thus improve the efficiency of the absorption and wetness in winter and spring. The risk of flooding can fields. Dikes and channels that have outlets for floodwater be reduced by levees, dikes, and diversions. can protect buildings and onsite sewage disposal systems In summer, irrigation is needed for the maximum from flooding. Alternative waste disposal systems may production of most crops. Furrow, border, corrugation, function properly on this unit. Suitable included soils are trickle, and sprinkler irrigation systems are suitable. The throughout the unit. Onsite investigation is needed to locate system used generally is governed by the crop that is such soils. grown. For the efficient application and removal of surface A drainage system is needed if roads or building irrigation water, land leveling is needed. To prevent foundations are constructed on this unit. The wetness can overirrigation and excessive erosion, applications of be reduced by installing drainage tile around footings. irrigation water should be adjusted to the available water Properly designing foundations and footings, diverting capacity, the rate of water intake, and the needs of the crop. runoff away from the buildings, and backfilling with material The use of pipe, ditch lining, or drop structures in irrigation that has a low shrink-swell potential help to prevent the ditches reduces water loss and the hazard of erosion. structural damage caused by shrinking and swelling. A subsurface drainage system can lower the water Properly designing buildings and roads helps to offset the table if a suitable outlet is available. Land smoothing and limited ability of the soil to support a load. open ditches can reduce surface wetness. Revegetating as soon as possible helps to control Returning all crop residue to the soil and using a erosion in disturbed areas around construction sites. cropping system that includes grasses, legumes, or Topsoil can be stockpiled and used to reclaim areas grass-legume mixtures help to maintain fertility and tilth. disturbed during construction. Because of a low amount of Leaving crop residue on or near the surface helps to rainfall in summer, irrigation is needed in areas that support conserve moisture and control erosion. lawn grasses, shrubs, vines, shade trees, or ornamental A tillage pan forms easily if the soil is tilled when wet. trees. Chiseling or subsoiling breaks up the pan. Surface crusting Roads and streets should be constructed above the and compaction can be minimized by returning crop residue expected level of flooding. The risk of flooding has been to the soil. reduced in some areas by the construction of large dams Solid-set sprinkler irrigation is the best method of and reservoirs upstream. controlling frost and providing adequate moisture for tree The vegetative site is Loamy Flood Plain, 18- to 30inch fruit. Compaction can be minimized by limiting the use of precipitation zone. equipment when the soil is wet and by planting a cover crop. A permanent cover crop helps to control runoff and 3E-Acker-Dumont complex, 12 to 35 percent north erosion. slopes. This map unit is on hillslopes. Elevation is 2,400 to Maintaining a protective plant cover in winter reduces the 4,000 feet. The mean annual precipitation is 45 to 60 soil loss resulting from flooding. Proper stocking rates, inches, the mean annual temperature is 45 to 50 degrees pasture rotation, and restricted grazing during wet periods F, and the average frost-free period is 100 to 160 days. The help to keep pastures in good condition and protect the soil native vegetation is mainly conifers and hardwoods and an from erosion. Grazing when the soil is wet results in understory of grasses, shrubs, and forbs. compaction of the surface layer, poor tilth, and excessive This unit is about 45 percent Acker soil and 30 percent runoff. Periodic mowing and clipping help to maintain Dumont soil. The components of this unit occur as areas so uniform plant growth, discourage selective grazing, and intricately intermingled that mapping them separately was reduce the extent of clumpy growth. Fertilizer is needed to not practical at the scale used. ensure the optimum growth of grasses and legumes. Included in this unit are small areas of Dubakella, Grasses respond to nitrogen, and legumes respond to sulfur Gravecreek, Norling, and Pearsoll soils; Abegg soils on and phosphorus. alluvial fans and near drainageways; Atring and Kanid soils The main limitations affecting homesite development on the more sloping parts of the landscape and on convex are the flooding, the moderately slow permeability, the slopes; and poorly drained soils near drainageways. Also wetness, the shrink -swell potential, and low strength. included are small areas of Acker and Dumont soils that The wetness, the moderately slow permeability, and have slopes of less than 12 or more than 35 percent. Included areas make up about 25 rutting and compaction. Puddling can occur when the soils percent of the total acreage. are wet. Using low-pressure ground equipment causes less The Acker soil is very deep and well drained. It formed in damage to the soils and helps to maintain productivity. colluvium derived dominantly from metamorphic rock. Compaction can be minimized by using suitable methods of Typically, the surface is covered with a layer of needles, harvesting, laying out skid trails in advance, and harvesting leaves, and twigs about 4 inches thick. The surface layer is timber when the soils are least susceptible to compaction. brown gravelly loam about 8 inches thick. The next layer is Ripping skid trails and landings when the soils are dry can yellowish brown gravelly clay loam about 9 inches thick. The improve the growth of plants. upper 11 inches of the subsoil is yellowish red gravelly clay Properly designed road drainage systems that include loam. The lower 32 inches is strong brown gravelly clay carefully located culverts help to control erosion. Seeding, loam. The depth to bedrock is 60 inches or more. In some mulching, and benching areas that have been cut and filled areas the surface layer is stony. also help to control erosion. Steep yarding paths, skid trails, Permeability is moderately slow in the Acker soil. and firebreaks are subject to rilling and gullying unless they Available water capacity is about 7 inches. The effective are protected by a plant cover or adequate water bars, or rooting depth is 60 inches or more. Runoff is medium, and both. the hazard of water erosion is moderate. The Dumont soil is subject to slumping. Road failure and The Dumont soil is very deep and well drained: It formed landslides are likely to occur after road construction and in colluvium derived dominantly from metamorphic rock. clearcutting. Slumping can be minimized by constructing Typically, the surface is covered with a layer of needles, logging roads in the less sloping areas, on better suited leaves, and twigs about 1 inch thick. The surface layer is soils if practical, and by installing properly designed road dark reddish brown gravelly clay loam about 4 inches thick. drainage systems. Skid trails and unsurfaced roads may be The next layer is dark reddish brown clay loam about 11 impassable during rainy periods. Logging roads require inches thick. The upper 36 inches of the subsoil is yellowish suitable surfacing for year-round use. red clay. The lower 9 inches is yellowish red clay loam. The Undesirable plants limit natural or artificial reforestation depth to bedrock is 60 inches or more. In some areas the unless intensive site preparation and maintenance surface layer is stony. measures are applied. Reforestation can be accomplished Permeability is moderately slow in the Dumont soil. by planting Douglas fir seedlings. Mulching around Available water capacity is about 9 inches. The effective seedlings helps to maintain the moisture supply in rooting depth is 60 inches or more. Runoff is medium, and summer and minimizes competition from undesirable the hazard of water erosion is moderate. understory plants. This unit is used for timber production and wildlife The vegetative site is Mixed Fir-Salal (rhododendron) habitat. It is suited to the production of Douglas fir. Other Forest. species that grow on this unit include incense cedar, western hemlock, and Pacific madrone. The understory 4E-Acker-Dumont complex, 12 to 35 percent south vegetation includes golden chinkapin, salal, and cascade slopes. This map unit is on hillslopes. Elevation is 2,400 to Oregongrape. 4,000 feet. The mean annual precipitation is 45 to 60 On the basis of a 100-year site curve, the mean site inches, the mean annual temperature is 45 to 50 degrees index for Douglas fir is 135 on both the Acker and Dumont F, and the average frost-free period is 100 to 160 days. The soils. The yield at culmination of the mean annual native vegetation is mainly conifers and hardwoods and an increment is 8,280 cubic feet per acre in a fully stocked, understory of grasses, shrubs, and forbs. even-aged stand of trees at 60 years and 63,910 board feet This unit is about 40 percent Acker soil and 30 percent per acre (Scribner rule) at 110 years. On the basis of a Dumont soil. The components of this unit occur as areas so 50-year curve, the mean site index is 100. intricately intermingled that mapping them separately was The main limitations affecting timber production are not practical at the scale used. erosion, compaction, and plant competition on both soils Included in this unit are small areas of Dubakella, and the hazard of slumping on the Dumont soil. Wheeled Gravecreek, Norling, and Pearsoll soils; Abegg soils on and tracked logging equipment can be used in the less alluvial fans and near drainageways; Atring and Kanid soils sloping areas, but cable yarding generally is safer in the on the more sloping parts of the landscape and on convex more sloping areas and results in less surface disturbance. slopes; and poorly drained soils near drainageways. Also Using standard wheeled and tracked equipment when the included are small areas of Acker and Dumont soils that soils are moist causes have slopes of less than 12 or more than 35 percent. Included areas make up about 30 rutting and compaction. Puddling can occur when the soils percent of the total acreage. are wet. Using low-pressure ground equipment causes less The Acker soil is very deep and well drained. It formed in damage to the soils and helps to maintain productivity. colluvium derived dominantly from metamorphic rock. Compaction can be minimized by using suitable methods of Typically, the surface is covered with a layer of needles, harvesting, laying out skid trails in advance, and harvesting leaves, and twigs about 4 inches thick. The surface layer is timber when the soils are least susceptible to compaction. brown gravelly loam about 8 inches thick. The next layer is Ripping skid trails and landings when the soils are dry can yellowish brown gravelly clay loam about 9 inches thick. The improve the growth of plants. upper 11 inches of the subsoil is yellowish red gravelly clay Properly designed road drainage systems that include loam. The lower 32 inches is strong brown gravelly clay carefully located culverts help to control erosion. Seeding, loam. The depth to bedrock is 60 inches or more. In some mulching, and benching areas that have been cut and filled areas the surface layer is stony. also help to control erosion. Steep yarding paths, skid trails, Permeability is moderately slow in the Acker soil. and firebreaks are subject to rilling and gullying unless they Available water capacity is about 7 inches. The effective are protected by a plant cover or adequate water bars, or rooting depth is 60 inches or more. Runoff is medium, and both. the hazard of water erosion is moderate: Because the Dumont soil is subject to slumping, road The Dumont soil is very deep and well drained. It formed failure and landslides are likely to occur after road in colluvium derived dominantly from metamorphic rock. construction and clearcutting. Slumping can be minimized Typically, the surface is covered with a layer of needles, by constructing logging roads in the less sloping areas, on leaves, and twigs about 1 inch thick. The surface layer is better suited soils if practical, and by installing properly dark reddish brown gravelly clay loam about 4 inches thick. designed road drainage systems. Skid trails and unsurfaced The next layer is dark reddish brown clay loam about 11 roads may be impassable during rainy periods. Logging inches thick. The upper 36 inches of the subsoil is yellowish roads require suitable surfacing for year-round use. red clay. The lower 9 inches is yellowish red clay loam. The A high temperature in the surface layer and an depth to bedrock is 60 inches or more. In some areas the insufficient moisture supply in summer increase the surface layer is stony. seedling mortality rate. To compensate for the expected Permeability is moderately slow in the Dumont soil. high mortality rate, the larger seedlings or a greater number Available water capacity is about 9 inches. The effective of seedlings should be planted. When the timber is rooting depth is 60 inches or more. Runoff is medium, and harvested, leaving some of the larger trees unharvested the hazard of water erosion is moderate. provides shade for seedlings. Reforestation can be This unit is used for timber production and wildlife accomplished by planting Douglas fir and ponderosa pine habitat. It is suited to the production of Douglas fir. Other seedlings. species that grow on this unit include incense cedar, sugar Undesirable plants limit natural or artificial pine, and Pacific madrone. The understory vegetation reforestation unless intensive site preparation and includes golden chinkapin, Whipplevine, and cascade maintenance measures are applied. Mulching around Oregongrape. seedlings helps to maintain the moisture supply in On the basis of a 100-year site curve, the mean site summer and minimizes competition from undesirable index for Douglas fir is 130 on both the Acker and Dumont understory plants. soils. The yield at culmination of the mean annual The vegetative site is Douglas Fir-Madrone- increment is 7,740 cubic feet per acre in a fully stocked, Chinkapin Forest. even-aged stand of trees at 60 years and 58,520 board feet per acre (Scribner rule) at 110 years. On the basis of a 5F-Acker-Norling complex, 35 to 55 percent north 50-year curve, the mean site index is 95. slopes. This map unit is on hillslopes. Elevation is 2,400 to The main limitations affecting timber production are 4,000 feet. The mean annual precipitation is 45 to 60 inches, erosion, compaction, seedling mortality, and plant the mean annual temperature is 45 to 50 degrees F, and the competition on both soils and slumping on the Dumont soil. average frost-free period is 100 to 160 days. The native Wheeled and tracked logging equipment can be used in the vegetation is mainly conifers and hardwoods and an less sloping areas, but cable yarding generally is safer in understory of grasses, shrubs, and forbs. the more sloping areas and results in less surface This unit is about 50 percent Acker soil and 35 percent disturbance. Using standard wheeled and tracked Norling soil. The components of this unit occur as areas so equipment when the soils are moist causes intricately intermingled that mapping them separately was not practical at the scale used. curve, the mean site index is 100. Included in this unit are small areas of Dubakella, On the basis of a 100-year site curve, the mean site Gravecreek, and Pearsoll soils; Dumont soils on the less index for Douglas fir is 130 on the Norling soil. The yield at sloping parts of the landscape and on concave slopes; and culmination of the mean annual increment is 7,740 cubic Atring and Kanid soils on the more sloping parts of the feet per acre in a fully stocked, even-aged stand of trees at landscape and on convex slopes. Also included are small 60 years and 58,520 board feet per acre (Scribner rule) at areas of Acker and Norling soils that have slopes of less 110 years. On the basis of a 50year curve, the mean site than 35 or more than 55 percent. Included areas make up index is 95. about 15 percent of the total acreage. The main limitations affecting timber production are the The Acker soil is very deep and well drained. It formed in slope, erosion, compaction, and plant competition. Also, colluvium derived dominantly from metamorphic rock. root growth is restricted by the bedrock underlying the Typically, the surface is covered with a layer of needles, Norling soil. As a result, trees are subject to windthrow. leaves, and twigs about 4 inches thick. The surface layer is Wheeled and tracked logging equipment can be used in brown gravelly loam about 8 inches thick. The next layer is the less sloping areas, but cable yarding generally is safer yellowish brown gravelly clay loam about 9 inches thick. The and results in less surface disturbance. Using standard upper 11 inches of the subsoil is yellowish red gravelly clay wheeled and tracked equipment when the soils are moist loam. The lower 32 inches is strong brown gravelly clay causes rutting and compaction. Puddling can occur when loam. The depth to bedrock is 60 inches or more. In some the soils are wet. Using low-pressure ground equipment areas the surface layer is stony. causes less damage to the soils and helps to maintain Permeability is moderately slow in the Acker soil. productivity. Compaction can be minimized by using Available water capacity is about 7 inches. The effective suitable methods of harvesting, laying out skid trails in rooting depth is 60 inches or more. Runoff is rapid, and the advance, and harvesting timber when the soils are least hazard of water erosion is high. susceptible to compaction. Ripping skid trails and landings The Norling soil is moderately deep and well drained. It when the soils are dry can improve the growth of plants. formed in colluvium derived dominantly from metamorphic Properly designed road drainage systems that include rock. Typically, the surface is covered with a layer of carefully located culverts help to control erosion. Seeding, needles, leaves, and twigs about 2 inches thick. The surface mulching, and benching areas that have been cut and filled layer is brown very gravelly loam about 5 inches thick. The also help to control erosion. Steep yarding paths, skid trails, next layer is brown gravelly clay loam about 5 inches thick. and firebreaks are subject to rilling and gullying unless they The upper 12 inches of the subsoil is yellowish brown are protected by a plant cover or adequate water bars, or gravelly clay loam. The lower 7 inches is yellowish brown both. Cutbanks occasionally slump when the soils are very cobbly clay loam. Weathered bedrock is at a depth of saturated. about 29 inches. The depth to bedrock ranges from 20 to 40 Constructing logging roads on the steeper slopes can inches. In some areas the surface layer is stony. result in a high risk of erosion. Material that is discarded Permeability is moderate in the Norling soil. Available when the roads are built can damage vegetation and is a water capacity is about 4 inches. The effective rooting depth potential source of sedimentation. If the material becomes is 20 to 40 inches. Runoff is rapid, and the hazard of water saturated, avalanches of debris can occur. End hauling of erosion is high. the waste material minimizes damage to the vegetation This unit is used for timber production and wildlife downslope and reduces the risk of sedimentation. Skid trails habitat. It is suited to the production of Douglas fir. and unsurfaced roads may be impassable during rainy Other species that grow on this unit include incense periods. Logging roads require suitable surfacing for cedar, golden chinkapin, and western hemlock. The year-round use. understory vegetation includes salal, cascade Undesirable plants limit natural or artificial reforestation Oregongrape, and deerfoot vanillaleaf. unless intensive site preparation and maintenance On the basis of a 100-year site curve, the mean site measures are applied. Reforestation can be accomplished index for Douglas fir is 135 on the Acker soil. The yield at by planting Douglas fir seedlings. Mulching around culmination of the mean annual increment is 8,280 cubic seedlings helps to maintain the moisture supply in feet per acre in a fully stocked, even-aged stand of trees at summer and minimizes competition from undesirable 60 years and 63,910 board feet per acre (Scribner rule) at understory plants. 110 years. On the basis of a 50-year The vegetative site is Mixed Fir-Salal (rhododendron) Forest. 6B-Agate -Winlo complex, 0 to 5 percent slopes. erosion is slight. The water table fluctuates between 0.5 foot This map unit is on fan terraces. Elevation is 1,100 to above and 0.5 foot below the surface from December 1,850 feet. The mean annual precipitation is 18 to 30 through April. inches, the mean annual temperature is 52 to 54 degrees This unit is used for hay and pasture, homesite F, and the average frost-free period is 150 to 180 days. development, and livestock grazing. The native vegetation is mainly grasses, shrubs, and The main limitations in the areas used for hay and forbs. pasture are wetness in winter and spring, droughtiness in This unit is about 55 percent Agate soil and 35 percent summer and fall, depth to the hardpan, compaction, and the Winlo soil. The components of this unit occur as areas so very gravelly surface layer of the Winlo soil. In some areas intricately intermingled that mapping them separately was ripping and shattering the hardpan increase the effective not practical at the scale used. The soils occur as patterned rooting depth and improve drainage. land. Areas of the Winlo soil are between and around areas If the pasture or range is overgrazed, the proportion of of the Agate soil, which is on circular mounds. preferred forage plants decreases and the proportion of less Included in this unit are small areas of Cove and Padigan preferred forage plants increases. The grazing system soils on concave slopes and near drainageways; Provig should maintain the desired balance of species in the plant soils, which have slopes of more than 3 percent; Brader and community. The wetness of the Winlo soil limits the choice Debenger soils on slightly raised knolls; and, West of of suitable forage plants and the period of cutting or grazing Phoenix, small areas of soils that are similar to the Agate and increases the risk of winterkill. The use of ground soil but are underlain by weakly cemented gravel and do not equipment is limited by the gravel and cobbles on the occur in a patterned land complex. Also included are small surface of the Winlo soil. Proper stocking rates, pasture areas of Agate and Winlo soils that have slopes of more rotation, and deferred grazing during wet periods help to than 5 percent. Included areas make up about 10 percent of keep the pasture or range in good condition and protect the the total acreage. soils from erosion. Grazing when the soils are wet results in The Agate soil is moderately deep to a hardpan and is compaction of the surface layer, poor tilth, and excessive well drained. It formed in alluvium derived from mixed runoff. Periodic mowing and clipping help to maintain sources. Typically, the surface layer is dark brown loam uniform plant growth, discourage selective grazing, and about 6 inches thick. The next layer is dark yellowish brown reduce the extent of clumpy growth. clay loam about 6 inches thick. The upper 13 inches of the The native vegetation suitable for grazing includes subsoil is dark brown clay loam. The lower 5 inches is a bluebunch wheatgrass, Lemmon needlegrass, and Idaho hardpan. The substratum to a depth of 62 inches is light fescue on the Agate soil and timothy and other olive brown extremely gravelly coarse sandy loam. Depth to wet-meadow grasses on the Winlo soil. Areas that support the hardpan is 20 to 30 inches. The depth to bedrock is 60 a large amount of competing vegetation can be improved inches or more. In some areas the surface layer is gravelly by prescribed burning or by chemical or mechanical or cobbly. treatment. Permeability is moderately slow in the Agate soil. Range seeding is suitable if the site is in poor condition. Available water capacity is about 4 inches. The effective The main limitations are wetness in winter and spring, rooting depth is 20 to 30 inches. Runoff is slow, and the droughtiness in summer and fall, and depth to the hardpan hazard of water erosion is slight. in the Winlo soil. The plants selected for seeding should be The Winlo soil is shallow to a hardpan and is somewhat those that meet the seasonal requirements of livestock or poorly drained. It formed in alluvium derived from mixed wildlife, or both. sources. Typically, the surface layer is very dark grayish In summer, irrigation is needed for the maximum brown very gravelly clay loam about 4 inches thick. The production of most forage crops. Sprinkler irrigation is the upper 5 inches of the subsoil is dark brown very gravelly best method of applying water. This method permits an clay. The lower 8 inches is a hardpan. The substratum to a even, controlled application of water, helps to prevent depth of 60 inches is light olive brown extremely gravelly excessive runoff, and minimizes the risk of erosion. Border coarse sandy loam. Depth to the hardpan is 7 to 15 inches. and contour flood irrigation systems also are suitable. To The depth to bedrock is 60 inches or more. In some areas prevent overirrigation and the development of a perched the surface layer is very cobbly or very gravelly clay. water table, applications of irrigation water should be Permeability is slow in the Winlo soil. Available water adjusted to the available water capacity, the rate of water capacity is about 1 inch. The effective rooting depth is 7 to intake, and the needs of the crop. For the efficient 15 inches. Runoff is ponded, and the hazard of water application and removal of surface irrigation water, leveling is needed on the more sloping parts of the landscape. Deep cuts, however, can expose the hardpan. The use of pipe, ditch lining, or drop near drainageways and on concave slopes; and soils that structures in irrigation ditches reduces water loss and the are similar to the Aspenlake soil but have a hardpan at a hazard of erosion. Fertilizer is needed to ensure the depth of more than 40 inches. Also included are small optimum growth of grasses and legumes. Grasses areas of soils that are similar to the Whiteface soil but have respond to nitrogen, and legumes respond to sulfur and a hardpan within a depth of 10 inches and Aspenlake and phosphorus. Whiteface soils that have slopes of more than 12 percent. The main limitations affecting homesite development Included areas make up about 25 percent of the total are the wetness and very gravelly surface layer in the acreage. Winlo soil and depth to the hardpan in both soils. The Aspenlake soil is moderately deep to a hardpan and These soils are poorly suited to standard systems of is well drained. It formed in alluvium derived dominantly waste disposal because of depth to the hardpan in both from andesite. Typically, the surface layer is dark brown soils and the wetness in the Winlo soil. The suitability of the stony loam about 4 inches thick. The next layer is dark soils for septic tank absorption fields can be improved by brown gravelly loam about 6 inches thick. The upper 16 ripping the hardpan, which improves permeability and inches of the subsoil also is dark brown gravelly loam. The drainage. Alternative waste disposal systems may function lower 7 inches is a hardpan. Depth to the hardpan is 20 to properly on these soils. Suitable included soils are in some 40 inches. areas of this unit. Onsite investigation is needed to locate Permeability is moderate in the Aspenlake soil. Available such soils. water capacity is about 4 inches. The effective rooting depth Because of the seasonal high water table perched is 20 to 40 inches. Runoff is slow, and the hazard of water above the hardpan in the Winlo soil, a drainage system is erosion is slight. needed on sites for buildings with basements and crawl The Whiteface soil is shallow to a hardpan and is well spaces. It also is needed if roads or building foundations drained. It formed in alluvium derived dominantly from are constructed. Excess water can be removed by suitably andesite. Typically, the surface layer is dark brown cobbly designed drainage ditches. loam about 8 inches thick. The next layer is dark brown Establishing plants is difficult in areas where the surface gravelly loam about 4 inches thick. The upper 4 inches of layer has been removed and the hardpan exposed. the subsoil is dark brown gravelly clay loam. The lower 7 Mulching and applying fertilizer help to establish plants in inches is a hardpan. Depth to the hardpan is 10 to 20 cut areas. Gravel and cobbles should be removed from inches. disturbed areas, particularly areas used for lawns. Topsoil Permeability is moderate in the Whiteface soil. Available can be stockpiled and used to reclaim areas disturbed water capacity is about 2 inches. The effective rooting depth during construction. In many areas it may be necessary to is 10 to 20 inches. Runoff is slow, and the hazard of water haul in topsoil for lawns and gardens. Because of a low erosion is slight. amount of rainfall in summer, irrigation is needed in areas This unit is used for timber production, livestock that support lawn grasses, shrubs, vines, shade trees, or grazing, and wildlife habitat. ornamental trees. This unit is suited to the production of ponderosa pine. The vegetative site in areas of the Agate soil is The plant community on the Aspenlake soil includes Biscuit-Scabland (mound), 18- to 26-inch precipitation ponderosa pine, Douglas fir, and white fir. The understory zone, and the one in areas of the Winlo soil is Poorly vegetation is mainly Douglas spirea, common snowberry, Drained Bottom. and Idaho fescue. The plant community on the Whiteface soil includes ponderosa pine and a few other conifers. The 7C-Aspenlake-Whiteface complex, 1 to 12 percent understory vegetation is mainly birchleaf slopes. This map unit is on alluvial fans. Elevation is 4,000 mountainmahogany, squawcarpet, and Ross sedge. to 4,500 feet. The mean annual precipitation is 20 to 35 On the basis of a 100-year site curve, the mean site inches, the mean annual temperature is 40 to 45 degrees F, index for ponderosa pine on the Aspenlake soil is 90. The and the average frost-free period is less than 100 days. The yield at culmination of the mean annual increment is 3,400 native vegetation is mainly conifers and an understory of cubic feet per acre in a fully stocked, even-aged stand of grasses, shrubs, and forbs. trees at 40 years and 37,960 board feet per acre (Scribner This unit is about 45 percent Aspenlake soil and 30 rule) at 130 years. percent Whiteface soil. The components of this unit occur On the basis of a 100-year site curve, the mean site as areas so intricately intermingled that mapping them index for ponderosa pine on the Whiteface soil is 75. The; separately was not practical at the scale used. yield at culmination of the mean annual increment is 3,100 Included in this unit are small areas of Hoxie, cubic feet per acre in a fully stocked, even-aged stand of Pokegema, and Woodcock soils; poorly drained soils trees at 50 years and 31,680 board feet per acre (Scribner rule) at 160 years. understory is overgrazed, the proportion of preferred The main limitations affecting timber production are forage plants decreases and the proportion of less compaction, erosion, seedling mortality, and plant preferred forage plants increases. competition. Also, the hardpan in the Whiteface soil A planned grazing system that includes timely deferment restricts root growth. As a result, trees are subject to of grazing, rotation grazing, and proper livestock distribution windthrow. helps to prevent overgrazing of the understory and damage Conventional methods of harvesting timber generally are to the soils. Grazing should be delayed until the more suitable, but the soils may be compacted if they are moist desirable forage plants have achieved enough growth to when heavy equipment is used. Puddling can occur when withstand grazing pressure and the soils are firm enough to the soils are wet. If the soils are excessively disturbed when withstand trampling by livestock. timber is harvested or logging roads are built, a larger Thinning, logging, and fire reduce the density of the number of rock fragments is left on the surface or the overstory canopy and increase the production of hardpan in the Whiteface soil may be exposed. Using understory vegetation. Areas that support a large amount low-pressure ground equipment causes less damage to the of competing vegetation can be improved by prescribed soils and helps to maintain productivity. Compaction can be burning or by chemical or mechanical treatment. Seeding minimized by using suitable methods of harvesting, laying disturbed areas to suitable plants increases forage out skid trails in advance, and harvesting timber when the production and reduces the hazard of erosion. soils are least susceptible to compaction. Ripping skid trails The vegetative site in areas of the Aspenlake soil is and landings when the soils are dry can improve the growth Wet Loamy Terrace, and the one in areas of the of plants. Whiteface soil is Ponderosa Pine-Fescue. Erosion can be controlled by carefully planning the construction and maintenance of logging roads, skid trails, 8A--Barhiskey gravelly loamy sand, 0 to 3 percent and landings. Seeding, mulching, and benching areas that slopes. This very deep, excessively drained soil is on have been cut and filled also help to control erosion. Skid outwash plains. It formed in sandy alluvium mixed with trails and unsurfaced roads may be impassable during pumice and volcanic ash. Elevation is 2,500 to 3,000 feet. rainy periods. Logging roads require suitable surfacing for The mean annual precipitation is 40 to 50 inches, the mean year-round use. annual temperature is 45 to 50 degrees F, and the average Severe frost can damage or kill seedlings. Air frost-free period is 100 to 150 days. The native vegetation is drainage may be restricted on this unit. Proper timber mainly conifers and hardwoods and an understory of harvesting methods can reduce the effect of frost on grasses, shrubs, and forbs. regeneration. Reforestation can be accomplished by Typically, the surface is covered with a layer of needles planting ponderosa pine seedlings. and twigs about 1 inch thick. The surface layer is black A high temperature in the surface layer during summer gravelly loamy sand about 4 inches thick. The next layer is and the low available water capacity increase the seedling dark brown gravelly sand about 15 inches thick. The mortality rate. The large number of rock fragments in both substratum to a depth of 60 inches is very dark gray soils and the shallowness of the Whiteface soil also gravelly sand. The depth to bedrock is 60 inches or more. increase the seedling mortality rate. To compensate for the In some areas the surface layer is cobbly. expected high mortality rate, the larger seedlings or a Included in this unit are small areas of Alcot, Barhiskey greater number of seedlings should be planted. When the Variant, and Crater Lake soils and soils that are similar to timber is harvested, leaving some of the larger trees the Barhiskey soil but have more than 35 percent rock unharvested provides shade for seedlings. fragments. Also included are small areas of Barhiskey soils Undesirable plants limit natural or artificial that have slopes of more than 3 percent. Included areas reforestation unless intensive site preparation and make up about 15 percent of the total acreage. maintenance measures are applied. Mulching around Permeability is rapid in the Barhiskey soil. Available seedlings helps to maintain the moisture supply in water capacity is about 4 inches. The effective rooting summer and minimizes competition from undesirable depth is 60 inches or more. Runoff is slow, and the hazard understory plants. of water erosion is slight. The main limitations affecting livestock grazing are This unit is used for timber production, livestock compaction and droughtiness. The Whiteface soil also is grazing, and wildlife habitat. limited by depth to the hardpan. The native vegetation This unit is suited to the production of Douglas fir suitable for grazing includes Idaho fescue, sedge, western fescue, and Wheeler bluegrass. If the and ponderosa pine. Other species that grow on this unit deferment of grazing, rotation grazing, and proper livestock include sugar pine and white fir. The understory distribution helps to prevent overgrazing of the understory vegetation includes Pacific serviceberry, tall and damage to the soil. Grazing should be delayed until the Oregongrape, and western fescue. more desirable forage plants have achieved enough growth On the basis of a 100-year site curve, the mean site to withstand grazing pressure and the soil is firm enough to index for Douglas fir is 120. The yield at culmination of the withstand trampling by livestock. Displacement of the mean annual increment is 6,900 cubic feet per acre in a surface layer occurs most readily when the soil is dry. fully stocked, even-aged stand of trees at 60 years and Thinning, logging, and fire reduce the density of the 52,440 board feet per acre (Scribner rule) at 120 years. On overstory canopy and increase the production of the basis of a 50-year curve, the mean site index is 90. understory vegetation. Areas that support a large amount On the basis of a 100-year site curve, the mean site of competing vegetation can be improved by prescribed index for ponderosa pine is 110. The yield at culmination burning or by chemical or mechanical treatment. Seeding of the mean annual increment is 4,880 cubic feet per acre disturbed areas to suitable plants increases forage in a fully stocked, even-aged stand of trees at 40 years production and reduces the risk of erosion. Success may and 50,820 board feet per acre (Scribner rule) at. 110 be limited, however, because of droughtiness and soil years. displacement. The main limitations affecting timber production are The vegetative site is Mixed Fir-Mixed Pine Forest. seedling mortality and the sandy surface layer. The sandy surface layer hinders the use of wheeled and tracked 9A-Barhiskey Variant gravelly loamy sand, 0 to 3 logging equipment, especially when the soil is saturated or percent slopes. This very deep, somewhat poorly drained very dry. Displacement of the surface layer occurs most soil is on outwash plains. It formed in alluvium mixed with readily when the soil is dry. Puddling can occur when the soil pumice and volcanic ash. Elevation is 2,500 to 2,700 feet. is wet. Using low-pressure ground equipment causes less The mean annual precipitation is 40 to 50 inches, the mean damage to the soil and helps to maintain productivity. annual temperature is 45 to 50 degrees F, and the average Compaction generally is not a problem on this unit. In areas frost-free period is 100 to 150 days. The native vegetation is where it is a concern, it can be minimized by using suitable mainly conifers and hardwoods and an understory of methods of harvesting, laying out skid trails in advance, and grasses, shrubs, and forbs. harvesting timber when the soil is least susceptible to Typically, the surface is covered with a layer of needles compaction. When dry, unsurfaced roads and skid trails are and twigs about 1 inch thick. The surface layer is black dusty. Logging roads require suitable surfacing for gravelly loamy sand about 8 inches thick. The next layer is year-round use. very dark grayish brown gravelly sand about 21 inches thick. Severe frost can damage or kill seedlings. Air drainage The substratum to a depth of 60 inches is very dark gray may be restricted on this unit. Proper timber harvesting gravelly sand. The depth to bedrock is 60 inches or more. methods can reduce the effect of frost on regeneration. Included in this unit are small areas of Alcot, Barhiskey, A high temperature in the surface layer during summer and Crater Lake soils; soils that are similar to the Barhiskey and the low available water capacity increase the seedling Variant soil but have more than 35 percent rock fragments; mortality rate. To compensate for the expected high mortality and very poorly drained, organic soils in depressions and rate, the larger seedlings or a greater number of seedlings near drainageways. Also included are small areas of should be planted. When the timber is harvested, leaving Barhiskey Variant soils that have slopes of more than 3 some of the larger trees unharvested provides shade for percent. Included areas make up about 10 percent of the seedlings. Reforestation can be accomplished by planting total acreage. ponderosa pine and Douglas fir seedlings (fig. 5). Permeability is rapid in the Barhiskey Variant soil. The main limitations affecting livestock grazing are Available water capacity is about 4 inches. The effective droughtiness and soil displacement. The native vegetation rooting depth is limited by the water table, which is at a depth suitable for grazing includes western fescue, tall trisetum, of 1 to 3 feet from January through August. Runoff is slow, and Alaska oniongrass. If the understory is overgrazed, the and the hazard of water erosion is slight. proportion of preferred forage plants decreases and the This unit is used for hay and pasture and for wildlife proportion of less preferred forage plants increases. habitat. It is well suited to hay and pasture. The main A planned grazing system that includes timely limitations are wetness in winter and spring and droughtiness in summer and fall. Tile drainage can Figure 5.-Ponderosa pine seedlings on Barhiskey gravelly loamy sand, 0 to 3 percent slopes.

lower the water table if a suitable outlet is available. Land soil is droughty, the applications should be light and smoothing and open ditches can reduce surface wetness. frequent. In summer, irrigation is needed for the maximum Wetness limits the choice of suitable forage plants and production of most forage crops. Because the rate of water the period of cutting or grazing and increases the risk of intake is rapid, sprinkler irrigation is the best method of winterkill. Proper stocking rates, pasture rotation, and applying water. This method permits an even, controlled restricted grazing during wet periods help to keep pastures application of water, helps to prevent excessive runoff, and in good condition and protect the soil from erosion. Grazing minimizes the risk of erosion. To prevent overirrigation and when the soil is wet results in compaction of the surface the leaching of plant nutrients, applications of irrigation layer, poor tilth, and excessive runoff. Periodic mowing and water should be adjusted to the available water capacity, clipping help to maintain uniform plant growth, discourage the rate of water intake, and the needs of the crop. selective grazing, and reduce the extent of clumpy growth. Because the Fertilizer is needed to ensure the optimum growth of grasses and legumes. Grasses respond to nitrogen, and structures in irrigation ditches reduces water loss and the legumes respond to sulfur and phosphorus. hazard of erosion. This unit is limited as a site for livestock watering Returning all crop residue to the soil and using a ponds and other water impoundments because of cropping system that includes grasses, legumes, or seepage. grass-legume mixtures help to maintain fertility and tilth. The vegetative site is Mixed Fir-Mixed Pine Forest, Leaving crop residue on or near the surface helps to Wet. conserve moisture and control erosion. A tillage pan forms easily if the soil is tilled when wet. 10B-Barron coarse sandy loam, 0 to 7 percent Chiseling or subsoiling breaks up the pan. Surface crusting slopes. This very deep, somewhat excessively drained and compaction can be minimized by returning crop residue soil is on alluvial fans. It formed in alluvium derived to the soil. dominantly from granitic rock. Elevation is 1,000 to 2,500 Solid-set sprinkler irrigation is the best method of feet. The mean annual precipitation is 18 to 35 inches, the controlling frost and providing adequate moisture for tree mean annual temperature is 50 to 54 degrees F, and the fruit. Compaction and displacement can be minimized by average frost-free period is 120 to 180 days. The native limiting the use of equipment when the soil is too wet or too vegetation is mainly conifers and hardwoods and an dry. A permanent cover crop helps to control runoff and understory of grasses, shrubs, and forbs. erosion. Typically, the surface layer is dark brown coarse sandy Proper stocking rates, pasture rotation, and restricted loam about 6 inches thick. The subsoil is brown sandy loam grazing during wet periods help to keep pastures in good about 17 inches thick. The upper 14 inches of the condition and protect the soil from erosion. Grazing when substratum is dark yellowish brown sandy loam. The lower the soil is wet results in compaction of the surface layer, part to a depth of 60 inches is brown sandy loam. The poor tilth, and excessive runoff. Periodic mowing and depth to bedrock is 60 inches or more. clipping help to maintain uniform plant growth, discourage Included in this unit are small areas of Clawson and selective grazing, and reduce the extent of clumpy growth. Kubli soils near drainageways and on concave slopes, Fertilizer is needed to ensure the optimum growth of Central Point soils on the lower parts of the landscape, grasses and legumes. Grasses respond to nitrogen, and and Ruch and Shefflein soils. Also included are small legumes respond to sulfur and phosphorus. areas of Barron soils that have slopes of more than 7 This unit is well suited to homesite development. It has percent. Included areas make up about 15 percent of the few limitations. Revegetating as soon as possible helps to total acreage. control erosion in disturbed areas around construction sites. Permeability is moderately rapid in the Barron soil. Topsoil can be stockpiled and used to reclaim areas Available water capacity is about 6 inches. The effective disturbed during construction. Because of droughtiness and rooting depth is 60 inches or more. Runoff is slow, and the a low amount of rainfall in summer, irrigation is needed in hazard of water erosion is slight. areas that support lawn grasses, shrubs, vines, shade This unit is used mainly for irrigated crops, such as trees, or ornamental trees. alfalfa hay, small grain, tree fruit, and grass-legume hay. This unit is suited to the production of ponderosa pine It also is used for timber production, pasture, and and Douglas fir. Other species that grow on this unit homesite development. include incense cedar, sugar pine, and Pacific madrone. This unit is well suited to irrigated crops. It is limited The understory vegetation includes deerbrush, tall mainly by droughtiness. In summer, irrigation is needed for Oregongrape, and western fescue. the maximum production of most crops. Furrow, border, On the basis of a 100-year site curve, the mean site corrugation, trickle, and sprinkler irrigation systems are index for ponderosa pine is 110. The yield at culmination of suitable. The system used generally is governed by the the mean annual increment is 4,880 cubic feet per acre in crop that is grown. For the efficient application and removal a fully stocked, even-aged stand of trees at 40 years and of surface irrigation water, leveling is needed on the more 50,820 board feet per acre (Scribner rule) at 110 years. sloping parts of the landscape. To prevent overirrigation On the basis of a 100-year site curve, the mean site and the leaching of plant nutrients, applications of irrigation index for Douglas fir is 105. The yield at culmination of the water should be adjusted to the available water capacity, mean annual increment is 5,460 cubic feet per acre in a the rate of water intake, and the needs of the crop. Because fully stocked, even-aged stand of trees at 60 years and the soil is droughty, the applications should be light and 45,600 board feet per acre (Scribner rule) at 150 years. On frequent. The use of pipe, ditch lining, or drop the basis of a 50-year curve, the mean site index is 85. The main limitations affecting timber production are sandy loam about 17 inches thick. The upper 14 inches of compaction, seedling mortality, and plant competition. the substratum is dark yellowish brown sandy loam. The Conventional methods of harvesting timber generally are lower part to a depth of 60 inches is brown sandy loam. suitable, but the soil may be compacted if it is moist when The depth to bedrock is 60 inches or more. heavy equipment is used. Displacement of the surface layer Included in this unit are small areas of Clawson and occurs most readily when the soil is dry. Puddling can occur Kubli soils near drainageways and on concave slopes, when the soil is wet. Using low-pressure ground equipment Central Point soils on the lower parts of the landscape, and causes less damage to the soil and helps to maintain Ruch and Shefflein soils. Also included are small areas of productivity. Compaction can be minimized by using Barron soils that have slopes of less than 7 or more than suitable methods of harvesting, laying out skid trails in 12 percent. Included areas make up about 15 percent of advance, and harvesting timber when the soil is least the total acreage. susceptible to compaction. Ripping skid trails and landings Permeability is moderately rapid in the Barron soil. when the soil is dry can improve the growth of plants. Available water capacity is about 6 inches. The effective Erosion can be controlled by carefully planning the rooting depth is 60 inches or more. Runoff is slow, and the construction and maintenance of logging roads, skid trails, hazard of water erosion is moderate. and landings. Seeding, mulching, and benching areas that This unit is used mainly for irrigated crops, such as have been cut and filled also help to control erosion. Skid alfalfa hay, small grain, tree fruit, and grass-legume hay. It trails and unsurfaced roads may be impassable during also is used for timber production, pasture, and homesite rainy periods. Logging roads require suitable surfacing for development. year-round use. This unit is well suited to irrigated crops. It is limited A high temperature in the surface layer and an mainly by the slope, the hazard of erosion, and insufficient moisture supply in summer increase the droughtiness. In summer, irrigation is needed for the seedling mortality rate. To compensate for the expected maximum production of most crops. Because of the slope, high mortality rate, the larger seedlings or a greater number sprinkler irrigation is the best method of applying water. This of seedlings should be planted. When the timber is method permits an even, controlled application of water, harvested, leaving some of the larger trees unharvested helps to prevent excessive runoff, and minimizes the risk of provides shade for seedlings. Reforestation can be erosion. To prevent overirrigation and the leaching of plant accomplished by planting Douglas fir and ponderosa pine nutrients, applications of irrigation water should be adjusted seedlings, to the available water capacity, the rate of water intake, and Undesirable plants limit natural or artificial the needs of the crop. Because the soil is droughty, the reforestation unless intensive site preparation and applications should be light and frequent. maintenance measures are applied. Mulching around Returning all crop residue to the soil and using a seedlings helps to maintain the moisture supply in cropping system that includes grasses, legumes, or summer and minimizes competition from undesirable grass-legume mixtures help to maintain fertility and tilth. understory plants. Leaving crop residue on or near the surface helps to Increased erosion, loss of plant nutrients, and water conserve moisture and control erosion. repellency are likely to result from fires of moderate A tillage pan forms easily if the soil is tilled when wet. intensity. Chiseling or subsoiling breaks up the pan. Surface crusting The vegetative site is Douglas Fir-Mixed Pine-Fescue and compaction can be minimized by returning crop residue Forest. to the soil. Solid-set sprinkler irrigation is the best method of 10C-Barron coarse sandy loam, 7 to 12 percent controlling frost and providing adequate moisture for tree slopes. This very deep, somewhat excessively drained fruit. Compaction and displacement can be minimized by soil is on alluvial fans. It formed in alluvium derived limiting the use of equipment when the soil is too wet or too dominantly from granitic rock. Elevation is 1,000 to 2,500 dry. A permanent cover crop helps to control runoff and feet. The mean annual precipitation is 18 to 35 inches, the erosion. mean annual temperature is 50 to 54 degrees F, and the Seedbeds should be prepared on the contour or across average frost-free period is 120 to 180 days. The native the slope where practical. Proper stocking rates, pasture vegetation is mainly conifers and hardwoods and an rotation, and restricted grazing during wet periods help to understory of grasses, shrubs, and forbs. keep pastures in good condition and protect the soil from Typically, the surface layer is dark brown coarse sandy erosion. Grazing when the soil is wet results in compaction loam about 6 inches thick. The subsoil is brown of the surface layer, poor tilth, and excessive runoff. Periodic mowing and clipping help to maintain uniform plant growth, discourage selective suitable surfacing for year-round use. grazing, and reduce the extent of clumpy growth. Fertilizer is A high temperature in the surface layer and an needed to ensure the optimum growth of grasses and insufficient moisture supply in summer increase the legumes. Grasses respond to nitrogen, and legumes seedling mortality rate. To compensate for the expected respond to sulfur and phosphorus. high mortality rate, the larger seedlings or a greater number This unit is well suited to homesite development. The of seedlings should be planted. When the timber is main limitation is the slope. Erosion is a hazard on the harvested, leaving some of the larger trees unharvested steeper slopes. Only the part of the site that is used for provides shade for seedlings. Reforestation can be construction should be disturbed. Revegetating as soon as accomplished by planting Douglas fir and ponderosa pine possible helps to control erosion in disturbed areas around seedlings. construction sites. Topsoil can be stockpiled and used to Undesirable plants limit natural or artificial reclaim areas disturbed during construction. Because of reforestation unless intensive site preparation and droughtiness and a low amount of rainfall in summer, maintenance measures are applied. Mulching around irrigation is needed in areas that support lawn grasses, seedlings helps to maintain the moisture supply in shrubs, vines, shade trees, or ornamental trees. summer and minimizes competition from undesirable This unit is suited to the production of ponderosa pine understory plants. and Douglas fir. Other species that grow on this unit Increased erosion, loss of plant nutrients, and water include incense cedar, sugar pine, and Pacific madrone. repellency are likely to result from fires of moderate The understory vegetation includes deerbrush, tall intensity. Oregongrape, and western fescue. The vegetative site is Douglas Fir-Mixed Pine-Fescue On the basis of a 100-year site curve, the mean site Forest. index for ponderosa pine is 110. The yield at culmination of the mean annual increment is 4,880 cubic feet per acre 11G-Beekman-Colestine gravelly loams, 50 to 80 in a fully stocked, even-aged stand of trees at 40 years percent north slopes. This map unit is on hillslopes. and 50,820 board feet per acre (Scribner rule) at 110 Elevation is 1,200 to 4,000 feet. The mean annual years. precipitation is 40 to 50 inches, the mean annual On the basis of a 100-year site curve, the mean site temperature is 45 to 52 degrees F, and the average index for Douglas fir is 105. The yield at culmination of the frost-free period is 100 to 160 days. The native vegetation mean annual increment is 5,460 cubic feet per acre in a is mainly conifers and hardwoods and an understory of fully stocked, even-aged stand of trees at 60 years and grasses, shrubs, and forbs. 45,600 board feet per acre (Scribner rule) at 150 years. On This unit is about 55 percent Beekman soil and 30 the basis of a 50-year curve, the mean site index is 85. percent Colestine soil. The components of this unit occur The main limitations affecting timber production are as areas so intricately intermingled that mapping them compaction, erosion, seedling mortality, and plant separately was not practical at the scale used. competition. Conventional methods of harvesting timber Included in this unit are small areas of Dubakella, generally are suitable, but the soil may be compacted if it is Goolaway, Musty, Pearsoll, Siskiyou, Speaker, and Tethrick moist when heavy equipment is used. Displacement of the soils; Josephine soils on concave slopes; and McMullin surface layer occurs most readily when the soil is dry. soils and Rock outcrop on ridges and convex slopes. Also Puddling can occur when the soil is wet. Using low-pressure included are small areas of Beekman and Colestine soils ground equipment causes less damage to the soil and helps that have slopes of less than 50 or more than 80 percent. to maintain productivity. Compaction can be minimized by Included areas make up about 15 percent of the total using suitable methods of harvesting, laying out skid trails in acreage. advance, and harvesting timber when the soil is least The Beekman soil is moderately deep and well drained. susceptible to compaction. Ripping skid trails and landings It formed in colluvium derived dominantly from metamorphic when the soil is dry can improve the growth of plants. rock. Typically, the surface layer is dark brown gravelly Erosion can be controlled by carefully planning the loam about 14 inches thick. The subsoil is grayish brown construction and maintenance of logging roads, skid trails, extremely gravelly loam about 14 inches thick. Bedrock is at and landings. Seeding, mulching, and benching areas that a depth of about 28 inches. The depth to bedrock ranges have been cut and filled also help to control erosion. Skid from 20 to 40 inches. In some areas the surface layer is trails and unsurfaced roads may be impassable during very gravelly loam or is stony. rainy periods. Logging roads require Permeability is moderate in the Beekman soil. Available water capacity is about 3 inches. The effective rooting depth is 20 to 40 inches. Runoff is rapid, and the hazard of water erosion is high. are protected by a plant cover or adequate water bars, or The Colestine soil is moderately deep and well drained. It both. formed in colluvium derived dominantly from metamorphic Building logging roads at midslope requires extensive rock. Typically, the surface is covered with a layer of cutting and filling and removes land from production. needles, leaves, and twigs about 1 inch thick. The .surface Material that is discarded when the roads are built can layer is very dark grayish brown and dark brown gravelly damage vegetation and is a potential source of loam about 9 inches thick. The subsoil is brown gravelly clay sedimentation. If the material becomes saturated, loam about 25 inches thick. Bedrock is at a depth of about avalanches of debris can occur. End hauling of the waste 34 inches. The depth to bedrock ranges from 20 to 40 material minimizes damage to the vegetation downslope inches. In some areas the surface layer is very gravelly loam and reduces the risk of sedimentation. Unsurfaced roads or is stony. may be impassable during rainy periods. Logging roads Permeability is moderate in the Colestine soil. Available require suitable surfacing for year-round use. water capacity is about 4 inches. The effective rooting depth Undesirable plants limit natural or artificial reforestation is 20 to 40 inches. Runoff is rapid, and the hazard of water unless intensive site preparation and maintenance erosion is high. measures are applied. Reforestation can be This unit is used for timber production and wildlife accomplished by planting Douglas fir seedlings. Mulching habitat. It is suited to the production of Douglas fir. Other around seedlings helps to maintain the moisture supply in species that grow on this unit include ponderosa pine, summer and minimizes competition from undesirable incense cedar, and sugar pine. The understory vegetation understory plants. includes golden chinkapin, cascade Oregongrape, and A high temperature in the surface layer during summer deerfoot vanillaleaf. and the low available water capacity increase the seedling On the basis of a 100-year site curve, the mean site mortality rate. The large number of rock fragments in the index for Douglas fir is 120 on the Beekman soil. The yield soils also increases the seedling mortality rate. To at culmination of the mean annual increment is 6,900 cubic compensate for the expected high mortality rate, the larger feet per acre in a fully stocked, even-aged stand of trees at seedlings or a greater number of seedlings should be 60 years and 52,440 board feet per acre (Scribner rule) at planted. When the timber is harvested, leaving some of the 120 years. On the basis of a 50-year curve, the mean site larger trees unharvested provides shade for seedlings. index is 85. Increased erosion, loss of plant nutrients, and water On the basis of a 100-year site curve, the mean site repellency are likely to result from fires of moderate index for Douglas fir is 125 on the Colestine soil. The yield intensity. at culmination of the mean annual increment is 7,320 cubic The vegetative site is Douglas Fir-Chinkapin Forest. feet per acre in a fully stocked, even-aged stand of trees at 60 years and 58,200 board feet per acre (Scribner rule) at 12G-Beekman-Colestine gravelly loams, 50 to 75 120 years. On the basis of a 50-year curve, the mean site percent south slopes. This map unit is on hillslopes. index is 90. Elevation is 1,200 to 4,000 feet. The mean annual The main limitations affecting timber production are the precipitation is 40 to 50 inches, the mean annual slope, erosion, plant competition, and seedling mortality. temperature is 45 to 52 degrees F, and the average Also, the bedrock restricts root growth. As a result, frost-free period is 100 to 160 days. The native vegetation windthrow is a hazard. is mainly conifers and hardwoods and an understory of The slope restricts the use of wheeled and tracked grasses, shrubs, and forbs. logging equipment. High-lead or other cable systems are This unit is about 55 percent Beekman soil and 25 the best methods of logging. If the soils are excessively percent Colestine soil. The components of this unit occur disturbed when timber is harvested or logging roads are as areas so intricately intermingled that mapping them built, a larger number of rock fragments is left on the separately was not practical at the scale used. surface. Ripping landings when the soils are dry can Included in this unit are small areas of Dubakella, improve the growth of plants. Goolaway, Musty, Pearsoll, Siskiyou, Speaker, and Tethrick Properly designed road drainage systems that include soils; Josephine soils on concave slopes; and McMullin carefully located culverts help to control erosion. Road cuts soils and Rock outcrop on ridges and convex slopes. Also can expose a large amount of fractured bedrock, which included are small areas of Beekman and Colestine soils limits the response to seeding and mulching. Cut slopes are that have slopes of less than 50 or more than 75 percent. subject to slumping where the bedrock is highly fractured or Included areas make up about 20 percent of the total where rock layers are parallel to the slopes. Steep yarding acreage. paths and firebreaks are subject to rilling and gullying unless they The Beekman soil is moderately deep and well drained. excessively disturbed when timber is harvested or logging It formed in colluvium derived dominantly from roads are built, a larger number of rock fragments is left on metamorphic rock. Typically, the surface layer is dark the surface. Ripping landings when the soils are dry can brown gravelly loam about 14 inches thick. The subsoil is improve the growth of plants. grayish brown extremely gravelly loam about 14 inches Properly designed road drainage systems that include thick. Bedrock is at a depth of about 28 inches. The depth carefully located culverts help to control erosion. Road cuts to bedrock ranges from 20 to 40 inches. In some areas the can expose a large amount of fractured bedrock, which surface layer is very gravelly loam or is stony. limits the response to seeding and mulching. Cut slopes are Permeability is moderate in the Beekman soil. Available subject to slumping where the bedrock is highly fractured or water capacity is about 3 inches. The effective rooting depth where rock layers are parallel to the slopes. Steep yarding is 20 to 40 inches. Runoff is rapid, and the hazard of water paths and firebreaks are subject to rilling and gullying unless erosion is high. they are protected by a plant cover or adequate water bars, The Colestine soil is moderately deep and well drained. It or both. formed in colluvium derived dominantly from metamorphic Building logging roads at midslope requires extensive rock. Typically, the surface is covered with a layer of cutting and filling and removes land from production. needles, leaves, and twigs about 1 inch thick. The surface Material that is discarded when the roads are built can layer is very dark grayish brown and dark brown gravelly damage vegetation and is a potential source of loam about 9 inches thick. The subsoil is brown gravelly clay sedimentation. If the material becomes saturated, loam about 25 inches thick. Bedrock is at a depth of about avalanches of debris can occur. End hauling of the waste 34 inches. The depth to bedrock ranges from 20 to 40 material minimizes damage to the vegetation downslope inches. In some areas the surface layer is very gravelly loam and reduces the risk of sedimentation. Unsurfaced roads or is stony. may be impassable during rainy periods. Logging roads Permeability is moderate in the Colestine soil. Available require suitable surfacing for year-round use. water capacity is about 4 inches. The effective rooting depth A high temperature in the surface layer during summer is 20 to 40 inches. Runoff is rapid, and the hazard of water and the low available water capacity increase the seedling erosion is high. mortality rate. The large number of rock fragments in the This unit is used for timber production and wildlife soils also increases the seedling mortality rate. To habitat. It is suited to the production of Douglas fir. Other compensate for the expected high mortality rate, the larger species that grow on the unit include ponderosa pine, seedlings or a greater number of seedlings should be sugar pine, and California black oak. The understory planted. When the timber is harvested, leaving some of the vegetation includes canyon live oak, deerbrush, and larger trees unharvested provides shade for seedlings. The western fescue. seedling mortality rate also can be reduced by providing On the basis of a 100-year site curve, the mean site artificial shade for seedlings (fig. 6). index for Douglas fir is 110 on the Beekman soil. The yield Reforestation can be accomplished by planting Douglas at culmination of the mean annual increment is 5,880 cubic fir and ponderosa pine seedlings. Undesirable plants limit feet per acre in a fully stocked, even-aged stand of trees at natural or artificial reforestation unless intensive site 60 years and 48,300 board feet per acre (Scribner rule) at preparation and maintenance measures are applied. 140 years. On the basis of a 50-year curve, the mean site Mulching around seedlings helps to maintain the moisture index is 75. supply in summer and minimizes competition from On the basis of a 100-year site curve, the mean site undesirable understory plants. index for Douglas fir is 115 on the Colestine soil. The yield Increased erosion, loss of plant nutrients, and water at culmination of the mean annual increment is 6,360 cubic repellency are likely to result from fires of moderate feet per acre in a fully stocked, even-aged stand of trees at intensity. 60 years and 50,700 board feet per acre (Scribner rule) at The vegetative site is Douglas Fir-Black Oak Forest. 130 years. On the basis of a 50-year curve, the mean site index is 85. 13C-Bly-Royst complex, 1 to 12 percent slopes. The main limitations affecting timber production are the slope, erosion, seedling mortality, and plant competition. This map unit is on plateaus. Elevation is 3,800 to 4,300 Also, the bedrock restricts root growth. As a result, feet. The mean annual precipitation is 15 to 25 inches, windthrow is a hazard. the mean annual temperature is 43 to 45 degrees F, and The slope restricts the use of wheeled and tracked the average frost-free period is less than 100 days. The logging equipment. High-lead or other cable systems are nature vegetation is mainly conifers the best methods of logging. If the soils are Figure 6.-Shade cards used to protect planted seedlings in a clearcut area of Beekman-Colestine gravelly loams, 50 to 75 percent south slopes.

and an understory of grasses, shrubs, and forbs. areas of Bly and Royst soils that have slopes of more This unit is about 55 percent Bly soil and 25 percent than 12 percent. Included areas make up about 20 Royst soil. The components of this unit occur as areas so percent of the total acreage. intricately intermingled that mapping them separately was The Bly soil is very deep and well drained. It formed in not practical at the scale used. residuum and colluvium derived dominantly from andesite Included in this unit are small areas of Greystoke, and volcanic ash. Typically, the surface is covered with a Merlin, and Kanutchan Variant soils, poorly drained soils layer of needles and twigs about 3 inches thick. The near drainageways and on concave slopes, and soils surface layer is very dark brown loam about 17 inches that are similar to the Bly soil but have bedrock within a thick. The upper 19 inches of the subsoil is dark brown clay depth of 60 inches. Also included are small loam. The lower 24 inches is dark yellowish brown clay loam. The depth to bedrock is 60 minimized by using suitable methods of harvesting, laying inches or more. In some areas the surface layer is very out skid trails in advance, and harvesting timber when the gravelly or very cobbly. soils are least susceptible to compaction. Ripping skid Permeability is moderately slow in the Bly soil. Available trails and landings when the soils are dry can improve the water capacity is about 9 inches. The effective rooting depth growth of plants. is 60 inches or more. Runoff is slow, and the hazard of Erosion can be controlled by carefully planning the water erosion is slight. construction and maintenance of logging roads, skid trails, The Royst soil is moderately deep and well drained. It and landings. Seeding, mulching, and benching areas that formed in residuum and colluvium derived dominantly from have been cut and filled also help to control erosion. Skid andesite and volcanic ash. Typically, the surface is covered trails and unsurfaced roads may be impassable during with a layer of needles and twigs about 1 inch thick. The rainy periods. Logging roads require suitable surfacing for surface layer is dark reddish brown gravelly loam about 11 year-round use. inches thick. The subsoil is dark reddish brown very cobbly Severe frost can damage or kill seedlings. Air clay loam about 10 inches thick. Weathered bedrock is at a drainage may be restricted on this unit. Proper timber depth of about 21 inches. It becomes harder as depth harvesting methods can reduce the effect of frost on increases. The depth to bedrock ranges from 20 to 40 regeneration. Reforestation can be accomplished by inches. In some areas the surface layer is very gravelly or planting ponderosa pine seedlings. very cobbly. A high temperature in the surface layer and an Permeability is slow in the Royst soil. Available water insufficient moisture supply in summer increase the capacity is about 3 inches. The effective rooting depth is 20 seedling mortality rate. The large number of rock fragments to 40 inches. Runoff is slow, and the hazard of water in the Royst soil also increases the seedling mortality rate. erosion is slight. To compensate for the expected high mortality rate, the This unit is used for timber production, livestock larger seedlings or a greater number of seedlings should be grazing, and wildlife habitat. planted. When the timber is harvested, leaving some of the This unit is suited to the production of ponderosa larger trees unharvested provides shade for seedlings. pine. Other species that grow on this unit include an The main limitation affecting livestock grazing is occasional Douglas fir and white fir. The understory compaction. The native vegetation suitable for grazing vegetation includes antelope bitterbrush, common includes sedge, Idaho fescue, and Wheeler bluegrass. If snowberry, and sedge. the understory is overgrazed, the proportion of preferred On the basis of a 100-year site curve, the mean site forage plants decreases and the proportion of less index for ponderosa pine on the Bly soil is 100. The yield preferred forage plants increases. at culmination of the mean annual increment is 4,080 cubic A planned grazing system that includes timely deferment feet per acre in a fully stocked, even-aged stand of trees at of grazing, rotation grazing, and proper livestock distribution 40 years and 44,640 board feet per acre (Scribner rule) at helps to prevent overgrazing of the understory and damage 120 years. to the soils. Grazing should be delayed until the more On the basis of a 100-year site curve, the mean site desirable forage plants have achieved enough growth to index for ponderosa pine on the Royst soil is 80. The yield withstand grazing pressure and the soils are firm enough to at culmination of the mean annual increment is 3,060 cubic withstand trampling by livestock. feet per acre in a fully stocked, even-aged stand of trees at Thinning, logging, and fire reduce the density of the 40 years and 33,750 board feet per acre (Scribner rule) at overstory canopy and increase the production of 150 years. understory vegetation. Areas that support a large amount The main limitations affecting timber production are of competing vegetation can be improved by prescribed compaction, erosion, and seedling mortality. Also, the burning or by chemical or mechanical treatment. Seeding bedrock underlying the Royst soil restricts root growth. As disturbed areas to suitable plants increases forage a result, windthrow is a hazard. production and reduces the risk of erosion. Conventional methods of harvesting timber generally are The vegetative site is Ponderosa Pine-Fescue. suitable, but the soils may be compacted if they are moist when heavy equipment is used. Puddling can occur when 13E-Bly-Royst complex, 12 to 35 percent slopes. the soils are wet. If the soils are excessively disturbed when This map unit is on hillslopes. Elevation is 3,800 to 4,300 timber is harvested or logging roads are built, a larger feet. The mean annual precipitation is 15 to 25 inches, number of rock fragments is left on the surface. Using the mean annual temperature is 43 to 45 low-pressure ground equipment causes less damage to the soils and helps to maintain productivity. Compaction can be degrees F, and the average frost-free period is less than 4,080 cubic feet per acre in a fully stocked, even-aged 100 days. The native vegetation is mainly conifers and an stand of trees at 40 years and 44,640 board feet per acre understory of grasses, shrubs, and forbs. (Scribner rule) at 120 years. This unit is about 55 percent Bly soil and 25 percent On the basis of a 100-year site curve, the. mean site Royst soil. The components of this unit occur as areas so index for ponderosa pine on the Royst soil is 80. The yield intricately intermingled that mapping them separately was at culmination of the mean annual increment is 3,060 cubic not practical at the scale used. feet per acre in a fully stocked, even-aged stand of trees at Included in this unit are small areas of Greystoke and 40 years and 33,750 board feet per acre (Scribner rule) at Merlin soils, poorly drained soils on concave slopes near 150 years. drainageways, and soils that are similar to the Bly soil but The main limitations affecting timber production are have bedrock within a depth of 60 inches. Also included are erosion, compaction, and seedling mortality. Also, the small areas of Bly and Royst soils that have slopes of less bedrock underlying the Royst soil restricts root growth. As than 12 or more than 35 percent. Included areas make up a result, windthrow is a hazard. about 20 percent of the total acreage. Wheeled and tracked logging equipment can be used in The Bly soil is very deep and well drained. It formed in the less sloping areas, but cable yarding generally is safer in colluvium derived dominantly from andesite and volcanic the more sloping areas and results in less surface ash. Typically, the surface is covered with a layer of disturbance. If the soils are excessively disturbed when needles and twigs about 3 inches thick. The surface layer timber is harvested or logging roads are built, a larger is very dark brown loam about 17 inches thick. The upper number of rock fragments is left on the surface. Using 19 inches of the subsoil is dark brown clay loam. The lower standard wheeled and tracked equipment when the soils are 24 inches is dark yellowish brown clay loam. The depth to moist causes rutting and compaction. Puddling can occur bedrock is 60 inches or more. In some areas the surface when the soils are wet. Using low-pressure ground layer is very gravelly, very cobbly, or stony. equipment causes less damage to the soils and helps to Permeability is moderately slow in the Bly soil. Available maintain productivity. Compaction can be minimized by water capacity is about 9 inches. The effective rooting depth using suitable methods of harvesting, laying out skid trails in is 60 inches or more. Runoff is medium, and the hazard of advance, and harvesting timber when the soils are least water erosion is moderate. susceptible to compaction. Ripping skid trails and landings The Royst soil is moderately deep and well drained. It when the soils are dry can improve the growth of plants. formed in colluvium derived dominantly from andesite and Properly designed road drainage systems that include volcanic ash. Typically, the surface is covered with a layer carefully located culverts help to control erosion. Seeding, of needles and twigs about 1 inch thick. The surface layer mulching, and benching areas that have been cut and filled is dark reddish brown gravelly loam about 11 inches thick. also help to control erosion. Steep yarding paths, skid trails, The subsoil is dark reddish brown very cobbly clay loam and firebreaks are subject to rilling and gullying unless they about 10 inches thick. Weathered bedrock is at a depth of are protected by a plant cover or adequate water bars, or about 21 inches. It becomes harder as depth increases. both. Skid trails and unsurfaced roads may be impassable The depth to bedrock ranges from 20 to 40 inches. In some during rainy periods. Logging roads require suitable areas the surface layer is very gravelly, very cobbly, or surfacing for year-round use. stony. A high temperature in the surface layer and an Permeability is slow in the Royst soil. Available water insufficient moisture supply in summer increase the seedling capacity is about 3 inches. The effective rooting depth is 20 mortality rate. The large number of rock fragments in the to 40 inches. Runoff is medium, and the hazard of water Royst soil also increases the seedling mortality rate. To erosion is moderate. compensate for the expected high mortality rate, the larger This unit is used for timber production, livestock seedlings or a greater number of seedlings should be grazing, and wildlife habitat. planted. When the timber is harvested, leaving some of the This unit is suited to the production of ponderosa larger trees unharvested provides shade for seedlings. pine. Other species that grow on this unit include an Reforestation can be accomplished by planting ponderosa occasional Douglas fir and white fir. The understory pine seedlings. vegetation includes antelope bitterbrush, common Severe frost can damage or kill seedlings. In the less snowberry, and sedge. sloping areas where air drainage may be restricted, proper On the basis of a 100-year site curve, the mean site timber harvesting methods can reduce the effect of frost on index for ponderosa pine on the Bly soil is 100. The yield regeneration. at culmination of the mean annual increment is The main limitations affecting livestock grazing are depth is 60 inches or more. Runoff is rapid, and the compaction and erosion. The native vegetation suitable for hazard of water erosion is high. grazing includes sedge, Idaho fescue, and Wheeler This unit is used for timber production, livestock bluegrass. If the understory is overgrazed, the proportion of grazing, and wildlife habitat. preferred forage plants decreases and the proportion of This unit is suited to the production of Douglas fir and less preferred forage plants increases. ponderosa pine. Other species that grow on this unit include A planned grazing system that includes timely deferment incense cedar, sugar pine, and California black oak. The of grazing, rotation grazing, and proper livestock distribution understory vegetation includes tall Oregongrape, common helps to prevent overgrazing of the understory and damage snowberry, and western fescue. to the soils. Grazing should be delayed until the more On the basis of a 100-year site curve, the mean site desirable forage plants have achieved enough growth to index for Douglas fir is 100. The yield at culmination of the withstand grazing pressure and the soils are firm enough to mean annual increment is 5,040 cubic feet per acre in a withstand trampling by livestock. fully stocked, even-aged stand of trees at 60 years and Thinning, logging, and fire reduce the density of the 39,750 board feet per acre (Scribner rule) at 150 years. On overstory canopy and increase the production of the basis of a 50-year curve, the mean site index is 70. understory vegetation. Areas that support a large amount On the basis of a 100-year site curve, the mean site of competing vegetation can be improved by prescribed index for ponderosa pine is 90. The yield at culmination of burning or by chemical or mechanical treatment. Seeding the mean annual increment is 3,400 cubic feet per acre in a disturbed areas to suitable plants increases forage fully stocked, even-aged stand of trees at 40 years and production and reduces the risk of erosion. 37,960 board feet per acre (Scribner rule) at 130 years. The vegetative site is Ponderosa Pine-Fescue. The main limitations affecting timber production are the slope, erosion, compaction, plant competition, and seedling 14G-Bogus very gravelly loam, 35 to 65 percent mortality. Wheeled and tracked logging equipment can be north slopes. This very deep, well drained soil is on used in the less sloping areas, but cable yarding generally hillslopes. It formed in colluvium derived dominantly from is safer and results in less surface disturbance. Using andesite, tuff, and breccia. Elevation is 3,000 to 4,000 standard wheeled and tracked equipment when the soil is feet. The mean annual -precipitation is 25 to 35 inches, moist causes rutting and compaction. Puddling can occur the mean annual temperature is 45 to 51 degrees F, and when the soil is wet. Using low-pressure ground equipment the average frost-free period is 100 to 160 days. The causes less damage to the soil and helps to maintain native vegetation is mainly conifers and hardwoods and productivity. Compaction can be minimized by using an understory of grasses, shrubs, and forbs. suitable methods of harvesting, laying out skid trails in Typically, the surface is covered with a layer of needles, advance, and harvesting timber when the soil is least leaves, and twigs about 1 inch thick. The surface layer is susceptible to compaction. Ripping skid trails and landings black very gravelly loam about 7 inches thick. The next when the soil is dry can improve the growth of plants. layer is very dark grayish brown very gravelly loam about 8 Properly designed road drainage systems that include inches thick. The upper 6 inches of the subsoil is dark carefully located culverts help to control erosion. Seeding, brown gravelly clay loam. The lower 44 inches is dark mulching, and benching areas that have been cut and filled yellowish brown and dark brown clay loam. The depth to also help to control erosion. Steep yarding paths, skid trails, bedrock is 60 inches or more. In some areas the surface and firebreaks are subject to rilling and gullying unless they layer is stony. are protected by a plant cover or adequate water bars, or Included in this unit are small areas of McMullin soils both. Cutbanks occasionally slump when the soil is and Rock outcrop on ridges and convex slopes, Heppsie saturated. soils, and soils that are similar to the Bogus soil but have Constructing logging roads on the steeper slopes can bedrock within a depth of 60 inches or have more than 35 result in a high risk of erosion. Material that is discarded percent rock fragments. Also included are small areas of when the roads are built can damage vegetation and is a Bogus soils that have slopes of less than 35 or more than potential source of sedimentation. If the material becomes 65 percent. Included areas make up about 20 percent of saturated, avalanches of debris can occur. End hauling of the total acreage. the waste material minimizes damage to the vegetation Permeability is slow in the Bogus soil. Available water downslope and reduces the risk of sedimentation. Skid trails capacity is about 8 inches. The effective rooting and unsurfaced roads may be impassable during rainy periods. Logging roads require suitable surfacing for year-round use. them separately was not practical at the scale used. Undesirable plants limit natural or artificial reforestation Included in this unit are small areas of Heppsie soils, unless intensive site preparation and maintenance Lorella soils and Rock outcrop on convex slopes, Carney measures are applied. Reforestation can be accomplished soils on concave slopes, and poorly drained soils near by planting Douglas fir and ponderosa pine seedlings. drainageways and on concave slopes. Also included are Mulching around seedlings helps to maintain the moisture small areas of soils that are similar to the Bogus soil but supply in summer and minimizes competition from have bedrock within a depth of 60 inches, soils that are undesirable understory plants. similar to the Skookum soil but have bedrock at a depth of A high temperature in the surface layer and an more than 40 inches, and Bogus and Skookum soils that insufficient moisture supply in summer increase the have slopes of more than 12 percent. Included areas make seedling mortality rate. To compensate for the expected up about 20 percent of the total acreage. high mortality rate, the larger seedlings or a greater number The Bogus soil is very deep and well drained. It formed in of seedlings should be planted. When the timber is residuum and colluvium derived dominantly from andesite, harvested, leaving some of the larger trees unharvested tuff, and breccia. Typically, the surface is covered with a provides shade for seedlings. layer of needles, leaves, and twigs about 1 inch thick. The The main limitations affecting livestock grazing are surface layer is black very gravelly loam about 7 inches compaction, erosion, and the slope. The native vegetation thick. The next layer is very dark grayish brown very gravelly suitable for grazing includes western fescue, tall trisetum, loam about 8 inches thick. The upper 6 inches of the subsoil and mountain brome. If the understory is overgrazed, the is dark brown gravelly clay loam. The lower 44 inches is proportion of preferred forage plants decreases and the dark yellowish brown and dark brown clay loam. The depth proportion of less preferred forage plants increases. to bedrock is 60 inches or more. In some areas the surface A planned grazing system that includes timely deferment layer is loam or is stony. of grazing, rotation grazing, and proper livestock distribution Permeability is slow in the Bogus soil. Available water helps to prevent overgrazing of the understory and damage capacity is about 8 inches. The effective rooting depth is to the soil. Grazing should be delayed until the more 60 inches or more. Runoff is slow, and the hazard of desirable forage plants have achieved enough growth to water erosion is slight. withstand grazing pressure and the soil is firm enough to The Skookum soil is moderately deep and well drained. It withstand trampling by livestock. formed in residuum and colluvium derived dominantly from Thinning, logging, and fire reduce the density of the andesite, tuff, and breccia. Typically, the surface layer is overstory canopy and increase the production of very dark brown very cobbly loam about 3 inches thick. The understory vegetation. Areas that support a large amount next layer is very dark grayish brown very cobbly loam of competing vegetation can be improved by prescribed about 5 inches thick. The upper 8 inches of the subsoil is burning or by chemical or mechanical treatment. Seeding very dark grayish brown very cobbly clay loam. The lower disturbed areas to suitable plants increases forage 12 inches is dark brown very cobbly and extremely cobbly production and reduces the risk of erosion. clay. Bedrock is at a depth of about 28 inches. The depth to The vegetative site is Douglas Fir-Mixed Pine-Sedge bedrock ranges from 20 to 40 inches. In some areas the Forest. surface layer is stony. Permeability is slow in the Skookum soil. Available water 15C-Bogus-Skookum complex, 1 to 12 percent capacity is about 2 inches. The effective rooting depth is 20 slopes. This map unit is on old terraces along the Klamath to 40 inches. Runoff is slow, and the hazard of water River. Elevation is 3,000 to 4,400 feet. The mean annual erosion is slight. precipitation is 18 to 25 inches, the mean annual This unit is used mainly for livestock grazing or wildlife temperature is 45 to 50 degrees F, and the average habitat. The Bogus soil also is used for timber production. frost-free period is 100 to 150 days. The native vegetation A few areas have been cleared and are used for pasture. on the Bogus soil is mainly conifers and hardwoods and an The main limitation affecting livestock grazing is understory of grasses, shrubs, and forbs. That on the compaction. The Skookum soil also is limited by cobbles Skookum soil is mainly grasses, shrubs, and forbs but and stones on the surface and by droughtiness. The includes scattered hardwoods. vegetation suitable for grazing includes western fescue, This unit is about 50 percent Bogus soil and 30 percent mountain brome, and tall trisetum on the Bogus soil and Skookum soil. The components of this unit occur as areas Idaho fescue, bluebunch wheatgrass, and pine so intricately intermingled that mapping bluegrass on the Skookum soil. If the range or understory laying out skid trails in advance, and harvesting timber is overgrazed, the proportion of preferred forage plants when the soil is least susceptible to compaction. Ripping decreases and the proportion of less preferred forage skid trails and landings when the soil is dry can improve the plants increases. Grazing should be delayed until the more growth of plants. desirable forage plants have achieved enough growth to Erosion can be controlled by carefully planning the withstand grazing pressure and the soils are firm enough to construction and maintenance of logging roads, skid trails, withstand trampling by livestock. and landings. Seeding, mulching, and benching areas that Suitable management practices on this unit include have been cut and filled, also help to control erosion. Skid proper grazing use, deferred grazing, rotation grazing, and trails and unsurfaced roads may be impassable during brush control. Areas that support a large amount of rainy periods. Logging roads require suitable surfacing for competing vegetation can be improved by chemical or year-round use. mechanical treatment. In places the use of ground A high temperature in the surface layer and an equipment is limited by the cobbles and stones on the insufficient moisture supply in summer increase the surface of the Skookum soil. seedling mortality rate. The large number of rock fragments Range seeding is suitable if the site is in poor condition. in some areas also increases the seedling mortality rate. To The main limitations are the very cobbly surface layer and compensate for the expected high mortality rate, the larger droughtiness of the Skookum soil. The plants selected for seedlings or a greater number of seedlings should be seeding should be those that meet the seasonal planted. When the timber is harvested, leaving some of the requirements of livestock or wildlife, or both. larger trees unharvested provides shade for seedlings. This unit is limited as a site for livestock watering Reforestation can be accomplished by planting ponderosa ponds and other water impoundments because of the pine and Douglas fir seedlings. depth to bedrock in the Skookum soil. Undesirable plants limit natural or artificial The Bogus soil is suited to the production of Douglas fir reforestation unless intensive site preparation and and ponderosa pine. Other species that grow on this unit maintenance measures are applied. Mulching around include incense cedar, sugar pine, and California black oak. seedlings helps to maintain the moisture supply in The understory vegetation includes tall Oregongrape, summer and minimizes competition from undesirable common snowberry, and western fescue understory plants. On the basis of a 100-year site curve, the mean site The vegetative site in areas of the Bogus soil is index for Douglas fir is 100 on the Bogus soil. The yield at Douglas Fir-Mixed Pine-Sedge Forest, and the one in culmination of the mean annual increment is 5,040 cubic areas of the Skookum soil is Droughty Slopes, 20- to feet per acre in a fully stocked, even-aged stand of trees at 30-inch precipitation zone. 60 years and 39,7.50 board feet per acre (Scribner rule) at 150 years. On the basis of a 50-year curve, the mean site 16A-Booth-Kanutchan Variant complex, 0 to 3 index is 70. percent slopes. This map unit is on plateaus. Elevation is On the basis of a 100-year site curve, the mean site 4,000 to 4,500 feet. The mean annual precipitation is about index for ponderosa pine is 90 on the Bogus soil. The yield 18 inches, the mean annual temperature is 43 to 45 at culmination of the mean annual increment is 3,400 cubic degrees F, and the average frost-free period is less than feet per acre in a fully stocked, even-aged stand of trees at 100 days. The native vegetation is mainly grasses, shrubs, 40 years and 37,960 board feet per acre (Scribner rule) at and forbs. 130 years. This unit is about 40 percent Booth soil and 35 percent The main limitations affecting timber production on the Kanutchan Variant soil. The components of this unit occur Bogus soil are compaction, erosion, seedling mortality, and as areas so intricately intermingled that mapping them plant competition. Conventional methods of harvesting separately was not practical at the scale used. timber generally are suitable, but the soil may be Included in this unit are small areas of Greystoke, compacted if it is moist when heavy equipment is used. Kanutchan, Merlin, Pinehurst, and Royst soils. Also Puddling can occur when the soil is wet. If the soil is included are small areas of Booth and Kanutchan Variant excessively disturbed when timber is harvested or logging soils that have slopes of more than 3 percent. Included roads are built, a larger number of rock fragments is left on areas make up about 25 percent of the total acreage. the surface. Using low-pressure ground equipment causes The Booth soil is moderately deep and well drained. It less damage to the soil and helps to maintain productivity. formed in colluvium derived dominantly from tuff. Typically, Compaction can be minimized by using suitable methods the surface layer is dark brown loam about 15 of harvesting, inches thick. The upper 11 inches of the subsoil is brown The vegetative site in areas of the Booth soil is clay. The lower 9 inches is dark yellowish brown clay. Claypan, 14- to 18-inch precipitation zone, and the one in Weathered bedrock is at a depth of about 35 inches. It areas of the Kanutchan Variant soil is Intermittent Swale. becomes harder as depth increases. The depth to bedrock ranges from 20 to 40 inches. In some areas the surface 17C-Brader-Debenger loams, 1 to 15 percent slopes. layer is stony or cobbly. This map unit is on knolls and ridges. Elevation is 1,000 to Permeability is slow in the Booth soil. Available water 3,500 feet. The mean annual precipitation is 18 to 35 capacity is about 4 inches. The effective rooting depth is 20 inches, the mean annual temperature is 50 to 54 degrees F, to 40 inches. Runoff is slow, and the hazard of water and the average frost-free period is 150 to 180 days. The erosion is slight. native vegetation is mainly hardwoods and an understory of The Kanutchan Variant soil is moderately deep and grasses, shrubs, and forbs. moderately well drained. It is in depressions. It formed in This unit is about 60 percent Brader soil and 20 percent alluvium derived dominantly from tuff and andesite. Debenger soil. The components of this unit occur as areas Typically, the surface layer is dark brown clay about 3 so intricately intermingled that mapping them separately inches thick. The subsoil is dark reddish brown clay about was not practical at the scale used. 18 inches thick. Bedrock is at a depth of about 21 inches. Included in this unit are small areas of Rock outcrop on The depth to bedrock ranges from 20 to 40 inches. ridges and convex slopes; Carney, Coker, and Darow soils Permeability is very slow in the Kanutchan Variant soil. on concave slopes; Padigan soils near drainageways; Available water capacity is about 3 inches. The effective Langellain and Ruch soils; and soils that are similar to the rooting depth is 20 to 40 inches. Runoff is ponded, and the Brader soil but have bedrock within a depth of 12 inches. hazard of water erosion is slight. The water table is 0.5 foot Also included are small areas of Brader and Debenger soils above the surface from February through May. that have slopes of more than 15 percent. Included areas This unit is used for livestock grazing and wildlife habitat. make up about 20 percent of the total acreage. The main limitations affecting livestock grazing are The Brader soil is shallow and well drained. It formed in compaction and droughtiness in summer and fall. The colluvium derived dominantly from sandstone. Typically, the Kanutchan Variant soil also is limited by the clayey surface surface layer is dark brown loam about 6 inches thick. The layer and wetness in winter and spring. The vegetation subsoil is dark reddish brown loam about 7 inches thick. suitable for grazing includes Idaho fescue, bluebunch Weathered bedrock is at a depth of about 13 inches. The wheatgrass, and Sandberg bluegrass on the Booth soil and depth to bedrock ranges from 12 to 20 inches. Nevada bluegrass and slender wheatgrass on the Permeability is moderate in the Brader soil. Available Kanutchan Variant soil. If the range is overgrazed, the water capacity is about 2 inches. The effective rooting depth proportion of preferred forage plants decreases and the is 12 to 20 inches. Runoff is slow or medium, and the proportion of less preferred forage plants increases. Grazing hazard of water erosion is slight or moderate. should be delayed until the more desirable forage plants on The Debenger soil is moderately deep and well drained. both soils have achieved enough growth to withstand It formed in colluvium derived dominantly from sandstone. grazing pressure and until the Kanutchan Variant soil is firm Typically, the surface layer is dark brown loam about 5 enough to withstand trampling by livestock. The Kanutchan inches thick. The next layer is reddish brown loam about 4 Variant soil generally is drained later in the year than the inches thick. The subsoil is reddish brown and yellowish red Booth soil. clay loam about 18 inches thick. Weathered bedrock is at a Suitable management practices on this unit include depth of about 27 inches. The depth to bedrock ranges from proper grazing use, deferred grazing, rotation grazing, and 20 to 40 inches. brush control. Areas that support a large amount of Permeability is moderate in the Debenger soil. Available competing vegetation can be improved by prescribed water capacity is about 5 inches. The effective rooting depth burning or by chemical or mechanical treatment. is 20 to 40 inches. Runoff is slow or medium, and the hazard Range seeding is suitable if the site is in poor condition. of water erosion is slight or moderate. The main limitations are the clayey surface layer and This unit is used for livestock grazing, hay and wetness in winter and spring in the Kanutchan Variant soil pasture, and homesite development. and the droughtiness of both soils in summer and fall. The The main limitations affecting livestock grazing are plants selected for seeding should be those that meet the compaction, erosion, droughtiness, and the depth to seasonal requirements of livestock or wildlife, or both. bedrock in the Brader soil. The vegetation suitable for fields because of the depth to bedrock. The absorption grazing includes Idaho fescue, bluebunch wheatgrass, and fields can be installed in some areas of included soils that pine bluegrass. If the range is overgrazed, the proportion of have bedrock at a greater depth. Onsite investigation is preferred forage plants decreases and the proportion of needed to locate such areas. less preferred forage plants increases. Grazing should be Revegetating as soon as possible helps to control delayed until the more desirable forage plants have erosion in disturbed areas around construction sites. achieved enough growth to withstand grazing pressure and Topsoil can be stockpiled and used to reclaim areas the soils are firm enough to withstand trampling by disturbed during construction. In many areas it may be livestock. necessary to haul in topsoil for lawns and gardens. Range seeding is suitable if the site is in poor condition. Because of a low amount of rainfall in summer, irrigation is The main limitations are droughtiness and the depth to needed in areas that support lawn grasses, shrubs, vines, bedrock in the Brader soil. The plants selected for seeding shade trees, or ornamental trees. should be those that meet the seasonal requirements of The vegetative site in areas of the Brader soil is Loamy livestock or wildlife, or both. Hills, 20- to 35-inch precipitation zone, and the one in areas Suitable management practices on this unit include of the Debenger soil is Loamy Slopes, 18- to 24-inch proper grazing use, deferred grazing, rotation grazing, and precipitation zone. brush control. Areas that support a large amount of competing vegetation can be improved by chemical or 17E-Brader-Debenger loams, 15 to 40 percent mechanical treatment. slopes. This map unit is on knolls and ridges (fig. 7). This unit is limited as a site for livestock watering Elevation is 1,000 to 3,500 feet. The mean annual ponds and other water impoundments because of the precipitation is 18 to 35 inches, the mean annual depth to bedrock. temperature is 50 to 54 degrees F, and the average The main limitations affecting the use of this unit for hay frost-free period is 150 to 180 days. The native and pasture are the depth to bedrock in the Brader soil and vegetation is mainly hardwoods and an understory of droughtiness in both soils. In summer, irrigation is needed grasses, shrubs, and forbs. for the maximum production of most forage crops. Sprinkler This unit is about 55 percent Brader soil and 20 percent irrigation is the best method of applying water. This method Debenger soil. The components of this unit occur as areas permits an even, controlled application of water, helps to so intricately intermingled that mapping them separately prevent excessive runoff, and minimizes the risk of erosion. was not practical at the scale used. Border and contour flood irrigation systems also are suitable Included in this unit are small areas of Rock outcrop on in the less sloping areas. For the efficient application and ridges and convex slopes, Carney and Darow soils on removal of surface irrigation water, land leveling is needed. concave slopes, Padigan soils near drainageways, Because of the depth to bedrock in the Brader soil, Heppsie soils on the steeper parts of the landscape, and however, leveling may expose bedrock. To prevent Langellain and Ruch soils. Also included are small areas of overirrigation and excessive erosion, applications of soils that are similar to the Debenger and Brader soils but irrigation water should be adjusted to the available water have more than 35 percent rock fragments, soils that are capacity, the rate of water intake, and the needs of the crop. similar to the Brader soil but have bedrock within a depth Proper stocking rates, pasture rotation, and restricted of 12 inches, and Brader and Debenger soils that have grazing during wet periods help to keep pastures in good slopes of less than 15 or more than 40 percent. Included condition and protect the soils from erosion. Grazing when areas make up about 25 percent of the total acreage. the soils are wet results in compaction of the surface layer, The Brader soil is shallow and well drained. It formed in poor tilth, and excessive runoff. Periodic mowing and colluvium derived dominantly from sandstone. Typically, the clipping help to maintain uniform plant growth, discourage surface layer is dark brown loam about 6 inches thick. The selective grazing, and reduce the extent of clumpy growth. subsoil is dark reddish brown loam about 7 inches thick. Fertilizer is needed to ensure the optimum growth of Weathered bedrock is at a depth of about 13 inches. The grasses and legumes. Grasses respond to nitrogen, and depth to bedrock ranges from 12 to 20 inches. legumes respond to sulfur and phosphorus. Permeability is moderate in the Brader soil. Available The main limitation affecting homesite development is water capacity is about 2 inches. The effective rooting the depth to bedrock. Cuts needed to provide essentially depth is 12 to 20 inches. Runoff is medium or rapid, and the level building sites can expose bedrock. hazard of water erosion is moderate or high. This unit is poorly suited to septic tank absorption The Debenger soil is moderately deep and well drained. It formed in colluvium derived dominantly from Figure 7.-An area of Brader-Debenger loams, 15 to 40 percent slopes, on a knoll. Abin silty clay loam, 0 to 3 percent slopes, is on the flood plain in the foreground.

sandstone. Typically, the surface layer is dark brown loam in the Brader soil, and the slope. The vegetation suitable about 5 inches thick. The next layer is reddish brown loam for grazing includes Idaho fescue, bluebunch wheatgrass, about 4 inches thick. The subsoil is reddish brown and and pine bluegrass. If the range is overgrazed, the yellowish red clay loam about 18 inches thick. Weathered proportion of preferred forage plants decreases and the bedrock is at a depth of about 27 inches. The depth to proportion of less preferred forage plants increases. bedrock ranges from 20 to 40 inches. Grazing should be delayed until the more desirable forage Permeability is moderate in the Debenger soil. Available plants have achieved enough growth to withstand grazing water capacity is about 5 inches. The effective rooting depth pressure and the soils are firm enough to withstand is 20 to 40 inches. Runoff is medium or rapid, and the trampling by livestock. hazard of water erosion is moderate or high. Range seeding is suitable if the site is in poor condition. This unit is used mainly for livestock grazing or The main limitations are droughtiness, the depth to homesite development. Some of the less sloping areas are bedrock in the Brader soil, and the slope. The plants used for hay and pasture. selected for seeding should be those that meet the The main limitations affecting livestock grazing are seasonal requirements of livestock or wildlife, or both. compaction, erosion, droughtiness, the depth to bedrock Suitable management practices on this unit include proper grazing use, deferred grazing, rotation grazing, and brush control. Areas that support a large amount of about 22 inches thick. The depth to bedrock is 60 competing vegetation can be improved by chemical or inches or more. mechanical treatment. The use of ground equipment and Included in this unit are small areas of Pinehurst and access by livestock are limited on some of the steeper Tatouche soils, Kanutchan and Sibannac soils on concave parts of the landscape. Constructing trails or walkways slopes, and Farva soils on convex slopes. Also included are allows livestock to graze in areas where access is limited. small areas of Bybee soils that have slopes of more than 12 This unit is limited as a site for livestock watering percent. Included areas make up about 20 percent of the ponds and other water impoundments because of the total acreage. slope and the depth to bedrock. Permeability is very slow in the Bybee soil. Available The main limitations affecting homesite development water capacity is about 9 inches. The effective rooting depth are the depth to bedrock and the slope. is limited by a dense layer of clay at a depth of 10 to 20 This unit is poorly suited to septic tank absorption fields inches. Runoff is slow, and the hazard of water erosion is because of the depth to bedrock and the slope. The slight. The water table, which is perched above the layer of absorption fields can be installed in some areas of the unit clay, is at a depth of 1 to 3 feet from December through where the soils are deeper over bedrock and are less May. sloping. Onsite investigation is needed to locate such This unit is used for timber production, livestock areas. grazing, and wildlife habitat. The slope limits the use of the steeper parts of this unit This unit is suited to the production of Douglas fir and for building site development. Cuts needed to provide white fir. Other species that grow on this unit include essentially level building sites can expose bedrock. Erosion incense cedar and ponderosa pine. The understory is a hazard on the steeper slopes. Only the part of the site vegetation includes Pacific serviceberry, tall Oregongrape, that is used for construction should be disturbed. and common snowberry. Revegetating as soon as possible helps to control erosion On the basis of a 100-year site curve, the mean site in disturbed areas around construction sites. Topsoil can index for Douglas fir is 100. The yield at culmination of the be stockpiled and used to reclaim areas disturbed during mean annual increment is 5,040 cubic feet per acre in a construction. In many areas it may be necessary to haul in fully stocked, even-aged stand of trees at 60 years and topsoil for lawns and gardens. Because of a low amount of 39,750 board feet per acre (Scribner rule) at 150 years. On rainfall in summer, irrigation is needed in areas that the basis of a 50-year curve, the mean site index is 75. support lawn grasses, shrubs, vines, shade trees, or The main limitations affecting timber production are ornamental trees. compaction, erosion, slumping, seasonal wetness, The vegetative site in areas of the Brader soil is Loamy seedling mortality, and plant competition. Also, the dense Hills, 20- to 35-inch precipitation zone, and the one in areas layer of clay restricts root growth. As a result, windthrow is of the Debenger soil is Loamy Slopes, 18- to 24-inch a hazard. precipitation zone. Conventional methods of harvesting timber generally are suitable, but the seasonal high water table restricts the use 18C-Bybee loam, 1 to 12 percent slopes. This very of equipment to midsummer, when the soil is dry, or to deep, somewhat poorly drained soil is on plateaus. It midwinter, when the soil is frozen. The soil may be formed in residuum and colluvium derived dominantly from compacted if it is moist when heavy equipment is used. andesite, tuff, and breccia. Elevation is 3,600 to 5,500 feet. Puddling can occur when the soil is wet. Using The mean annual precipitation is 30 to 50 inches, the mean low-pressure ground equipment causes less damage to the annual temperature is 40 to 45 degrees F, and the average soil and helps to maintain productivity. Compaction can be frost-free period is less than 100 days. The native minimized by using suitable methods of harvesting, laying vegetation is mainly conifers and an understory of grasses, out skid trails in advance, and harvesting timber when the shrubs, and forbs. soil is least susceptible to compaction. Ripping skid trails Typically, the surface is covered with a layer of needles and landings when the soil is dry can improve the growth of and twigs about 1/2 inch thick. The surface layer is very plants. dark grayish brown loam about 4 inches thick. The next This unit is subject to severe slumping, especially in layer is very dark grayish brown clay loam about 6 inches areas of road cuts. Road failure and landslides are likely to thick. The upper 4 inches of the subsoil is brown clay. The occur after road construction and clearcutting. Skid trails lower 24 inches is light yellowish brown clay. The and unsurfaced roads may be impassable during rainy substratum is light yellowish brown clay periods. Logging roads require suitable surfacing for year-round use. Erosion can be controlled by carefully planning the percent Tatouche soil. The components of this unit occur construction and maintenance of logging roads, skid trails, as areas so intricately intermingled that mapping them and landings. Seeding, mulching, and benching areas that separately was not practical at the scale used. have been cut and filled also help to control erosion. Included in this unit are small areas of Pinehurst soils, Severe frost can damage or kill seedlings. Air Kanutchan and Sibannac soils on concave slopes, Farva drainage is restricted on this unit. Proper timber and Woodseye soils on convex slopes, and soils that are harvesting methods can reduce the effect of frost on similar to the Tatouche soil but have bedrock within a depth regeneration. Reforestation can be accomplished by of 60 inches. Also included are small areas of Bybee and planting seedlings of frost-tolerant species, such as Tatouche soils that have slopes of less than 12 or more ponderosa pine. The seasonal wetness increases the than 35 percent. Included areas make up about 15 percent seedling mortality rate. Also, seedlings planted in the less of the total acreage. fertile clayey subsoil grow poorly. The Bybee soil is very deep and somewhat poorly Undesirable plants limit natural or artificial drained. It formed in colluvium derived dominantly from reforestation unless intensive site preparation and andesite, tuff, and breccia. Typically, the surface is covered maintenance measures are applied. Mulching around with a layer of needles and twigs about 1/2 inch thick. The seedlings helps to maintain the moisture supply in surface layer is very dark grayish brown loam about 4 summer and minimizes competition from undesirable inches thick. The next layer is very dark grayish brown clay understory plants. loam about 6 inches thick. The upper 4 inches of the subsoil The main limitations affecting livestock grazing are is brown clay. The lower 24 inches is light yellowish brown compaction and the seasonal wetness. The native clay. The substratum is light yellowish brown clay about 22 vegetation suitable for grazing includes western fescue, inches thick. The depth to bedrock is 60 inches or more. mountain brome, tall trisetum, and Alaska oniongrass. If the Permeability is very slow in the Bybee soil. Available understory is overgrazed, the proportion of preferred forage water capacity is about 9 inches. The effective rooting plants decreases and the proportion of less preferred forage depth is limited by a dense layer of clay at a depth of 10 to plants increases. 20 inches. Runoff is medium, and the hazard of water A planned grazing system that includes timely deferment erosion is moderate. The water table, which is perched of grazing, rotation grazing, and proper livestock distribution above the layer of clay, is at a depth of 1 to 3 feet from helps to prevent overgrazing of the understory and damage December through May. to the soil. Because this unit remains wet for long periods in The Tatouche soil is very deep and well drained. It spring, grazing should be delayed until the soil is firm and formed in colluvium derived dominantly from andesite, tuff, the more desirable forage plants have achieved enough and breccia. Typically, the surface is covered with a layer growth to withstand grazing pressure. Compaction can be of needles and twigs about 2 inches thick. The surface minimized by grazing first in the areas that dry out earliest. layer is very dark brown gravelly loam about 11 inches Thinning, logging, and fire reduce the density of the thick. The upper 8 inches of the subsoil is dark brown overstory canopy and increase the production of gravelly clay loam. The lower 41 inches is dark brown clay. understory vegetation. Areas that support a large amount The substratum to a depth of 73 inches is strong brown of competing vegetation can be improved by prescribed clay loam. The depth to bedrock is 60 inches or more. In burning or by chemical or mechanical treatment. Seeding some areas the surface layer is stony or cobbly. disturbed areas to suitable plants increases forage Permeability is moderately slow in the Tatouche soil. production and reduces the risk of erosion. Available water capacity is about 8 inches. The effective The vegetative site is Mixed Fir-Serviceberry Forest. rooting depth is 60 inches or more. Runoff is medium, and the hazard of water erosion is moderate. 19E-Bybee-Tatouche complex, 12 to 35 percent This unit is used for timber production, livestock north slopes. This map unit is on hillslopes. Elevation is grazing, and wildlife habitat. 3,600 to 5,500 feet. The mean annual precipitation is 30 to This unit is suited to the production of Douglas fir and 50 inches, the mean annual temperature is 40 to 45 white fir. Other species that grow on this unit include degrees F, and the average frost-free period is less than incense cedar and ponderosa pine. The understory 100 days. The native vegetation is mainly conifers and an vegetation includes creambush oceanspray, cascade understory of grasses, shrubs, and forbs. Oregongrape, and whitevein shinleaf. This unit is about 55 percent Bybee soil and 30 On the basis of a 100-year site curve, the mean site index for Douglas fir is 115 on the Bybee soil. The yield at culmination of the mean annual increment is 6,360 cubic feet per acre in a fully stocked, even-aged stand of pine seedlings. Mulching around seedlings helps to trees at 60 years and 50,700 board feet per acre (Scribner maintain the moisture supply in summer and minimizes rule) at 130 years. On the basis of a 50-year curve, the competition from undesirable understory plants. mean site index is 85. Severe frost can damage or kill seedlings. In the less On the basis of a 100-year site curve, the mean site sloping areas where air drainage may be restricted, proper index for Douglas fir is 125 on the Tatouche soil. The yield timber harvesting methods can reduce the effect of frost on at culmination of the mean annual increment is 7,320 cubic regeneration. The seasonal wetness in the Bybee soil feet per acre in a fully stocked, even-aged stand of trees at increases the seedling mortality rate. Also, seedlings 60 years and 58,200 board feet per acre (Scribner rule) at planted in the less fertile clayey subsoil grow poorly. 120 years. On the basis of a 50-year curve, the mean site The main limitations affecting livestock grazing are index is 90. compaction, erosion, and the seasonal wetness of the The main limitations affecting timber production are Bybee soil. The native vegetation suitable for grazing erosion, compaction, plant competition, and seedling includes western fescue, mountain brome, and Alaska mortality. The dense layer of clay in the Bybee soil restricts oniongrass. If the understory is overgrazed, the proportion root growth. As a result, windthrow is a, hazard. This soil of preferred forage plants decreases and the proportion of also is limited by seasonal wetness and slumping. less preferred forage plants increases. The seasonal high water table in the Bybee soil restricts A planned grazing system that includes timely deferment the use of equipment to midsummer, when the soil is dry, or of grazing, rotation grazing, and proper livestock distribution to midwinter, when the soil is frozen. Wheeled and tracked helps to prevent overgrazing of the understory and damage logging equipment can be used in the less sloping areas, to the soils. The Bybee soil remains wet for long periods in but cable yarding generally is safer in the more sloping spring; therefore, grazing should be delayed until the soil is areas and results in less surface disturbance. Using firm and the more desirable forage plants have achieved standard wheeled and tracked equipment when the soils enough growth to withstand grazing pressure. Compaction are moist causes rutting and compaction. Puddling can can be minimized by grazing first in the areas that dry out occur when the soils are wet. Using low-pressure ground earliest. equipment causes less damage to the soils and helps to Thinning, logging, and fire reduce the density of the maintain productivity. Compaction can be minimized by overstory canopy and increase the production of using suitable methods of harvesting, laying out skid trails in understory vegetation. Areas that support a large amount advance, and harvesting timber when the soils are least of competing vegetation can be improved by prescribed susceptible to compaction. Ripping skid trails and landings burning or by chemical or mechanical treatment. Seeding when the soils are dry can improve the growth of plants. disturbed areas to suitable plants increases forage Properly designed road drainage systems that include production and reduces the risk of erosion. carefully located culverts help to control erosion. Seeding, The vegetative site is Mixed Fir-Oceanspray Forest. mulching, and benching areas that have been cut and filled also help to control erosion. Steep yarding paths, skid trails, 20E-Bybee-Tatouche complex, 12 to 35 percent and firebreaks are subject to rilling and gullying unless they south slopes. This map unit is on hillslopes. Elevation is are protected by a plant cover or adequate water bars, or 3,600 to 5,500 feet. The mean annual precipitation is 30 to both. 50 inches, the mean annual temperature is 40 to 45 The Bybee soil is subject to severe slumping. Road degrees F, and the average frost-free period is less than failure and landslides are likely to occur after road 100 days. The native vegetation is mainly conifers and an construction and clearcutting. Slumping can be minimized understory of grasses, shrubs, and forbs. by constructing logging roads in the less sloping areas, on This unit is about 55 percent Bybee soil and 30 percent better suited soils if practical, and by installing properly Tatouche soil. The components of this unit occur as areas designed road drainage systems. Skid trails and so intricately intermingled that mapping them separately unsurfaced roads may be impassable during rainy periods. was not practical at the scale used. Logging roads require suitable surfacing for year-round Included in this unit are small areas of Pinehurst soils, use. Kanutchan and Sibannac soils on concave slopes, Farva Undesirable plants limit natural or artificial reforestation and Woodseye soils and Rock outcrop on convex slopes, unless intensive site preparation and maintenance and soils that are similar to the Tatouche soil but have measures are applied. Reforestation can be accomplished bedrock within a depth of 60 inches. Also included are small by planting Douglas fir and ponderosa areas of Bybee and Tatouche soils that have slopes of less than 12 or more than 35 stand of trees at 60 years and 48,300 board feet per acre percent. Included areas make up about 15 percent of the (Scribner rule) at 140 years. On the basis of a 50-year total acreage. curve, the mean site index is 85. The Bybee soil is very deep and somewhat poorly The main limitations affecting timber production are drained. It formed in colluvium derived dominantly from erosion, compaction, seedling mortality, and plant andesite, tuff, and breccia. Typically, the surface is covered competition. The dense layer of clay in the Bybee soil with a layer of needles and twigs about 1/2 inch thick. The restricts root growth. As a result, windthrow is a hazard. surface layer is very dark grayish brown loam about 4 This soil also is limited by seasonal wetness and slumping. inches thick. The next layer is very dark grayish brown clay The seasonal high water table in the Bybee soil restricts loam about 6 inches thick. The upper 4 inches of the subsoil the use of equipment to midsummer, when the soil is dry, or is brown clay. The lower 24 inches is light yellowish brown to midwinter, when the soil is frozen. Wheeled and tracked clay. The substratum is light yellowish brown clay about 22 logging equipment can be used in the less sloping areas, inches thick. The depth to bedrock is 60 inches or more. but cable yarding generally is safer in the more sloping Permeability is very slow in the Bybee soil. Available areas and results in less surface disturbance. Using water capacity is about 9 inches. The effective rooting standard wheeled and tracked equipment when the soils are depth is limited by a dense layer of clay at a depth of 10 to moist causes rutting and compaction. Puddling can occur 20 inches. Runoff is medium, and the hazard of water when the soils are wet. Using low-pressure ground erosion is moderate. The water table, which is perched equipment causes less damage to the soils and helps to above the layer of clay, is at a depth of 1 to 3 feet from maintain productivity. Compaction can be minimized by December through May. using suitable methods of harvesting, laying out skid trails in The Tatouche soil is very deep and well drained. It advance, and harvesting timber when the soils are least formed in colluvium derived dominantly from andesite, tuff, susceptible to compaction. Ripping skid trails and landings and breccia. Typically, the surface is covered with a layer when the soils are dry can improve the growth of plants. of needles and twigs about 2 inches thick. The surface Properly designed road drainage systems that include layer is very dark brown gravelly loam about 11 inches carefully located culverts help to control erosion. Seeding, thick. The upper 8 inches of the subsoil is dark brown mulching, and benching areas that have been cut and filled gravelly clay loam. The lower 41 inches is dark brown clay. also help to control erosion. Steep yarding paths, skid trails, The substratum to a depth of 73 inches is strong brown and firebreaks are subject to rilling and gullying unless they clay loam. The depth to bedrock is 60 inches or more. In are protected by a plant cover or adequate water bars, or some areas the surface layer is stony or cobbly. both. Permeability is moderately slow in the Tatouche soil. The Bybee soil is subject to severe slumping. Road Available water capacity is about 8 inches. The effective failure and landslides are likely to occur after road rooting depth is 60 inches or more. Runoff is medium, and construction and clearcutting. Slumping can be minimized the hazard of water erosion is moderate. by constructing logging roads in the less sloping areas, on This unit is used for timber production, livestock better suited soils if practical, and by installing properly grazing, and wildlife habitat. designed road drainage systems. Skid trails and This unit is suited to the production of Douglas fir and unsurfaced roads may be impassable during rainy periods. white fir. Other species that grow on this unit include Logging roads require suitable surfacing for year-round incense cedar and ponderosa pine. The understory use. vegetation includes Pacific serviceberry, tall Oregongrape, A high temperature in the surface layer and an and common snowberry. insufficient moisture supply in summer increase the On the basis of a 100-year site curve, the mean site seedling mortality rate. To compensate for the expected index for Douglas fir is 100 on the Bybee soil. The yield at high mortality rate, the larger seedlings or a greater number culmination of the mean annual increment is 5,040 cubic of seedlings should be planted. When the timber is feet per acre in a fully stocked, even-aged stand of trees at harvested, leaving some of the larger trees unharvested 60 years and 39,750 board feet per acre (Scribner rule) at provides shade for seedlings. Reforestation can be 150 years. On the basis of a 50-year curve, the mean site accomplished by planting Douglas fir and ponderosa pine index is 80. seedlings. On the basis of a 100-year site curve, the mean site Severe frost can damage or kill seedlings. In the less index for Douglas fir is 110 on the Tatouche soil. The yield sloping areas where air drainage may be restricted, proper at culmination of the mean annual increment is 5,880 timber harvesting methods can reduce the effect cubic feet per acre in a fully stocked, even-aged of frost on regeneration. The seasonal wetness in the Included in this unit are small areas of Riverwash; Cove Bybee soil increases the seedling mortality rate. Also, soils on concave slopes; Central Point, Medford, and seedlings planted in the less fertile clayey subsoil grow Takilma soils on terraces; Abin, Evans, and Newberg soils; poorly. and poorly drained soils. Also included are small areas of Undesirable plants limit natural or artificial Camas soils that have slopes of more than 3 percent. reforestation unless intensive site preparation and Included areas make up about 20 percent of the total maintenance measures are applied. Mulching around acreage. seedlings helps to maintain the moisture supply in Permeability is moderately rapid in the upper part of the summer and minimizes competition from undesirable Camas soil and very rapid in the lower part. Available water understory plants. capacity is about 3 inches. The effective rooting depth is 60 The main limitations affecting livestock grazing are inches or more. The substratum can restrict the penetration compaction, erosion, and the seasonal wetness of the of roots, however, because of droughtiness. Runoff is slow, Bybee soil. The native vegetation suitable for grazing and the hazard of water erosion is slight. This soil is includes western fescue, mountain brome, tall trisetum, and occasionally flooded for brief periods from November Alaska oniongrass. If the understory is overgrazed, the through May. proportion of preferred forage plants decreases and the This unit is used mainly for hay and pasture. It also is proportion of less preferred forage plants increases. used for cultivated crops, such as small grain, and for A planned grazing system that includes timely deferment homesite development. of grazing, rotation grazing, and proper livestock distribution This unit is suited to hay and pasture. The main helps to prevent overgrazing of the understory and damage limitations are the flooding and droughtiness. The risk of to the soils. The Bybee soil remains wet for long periods in flooding can be reduced by levees, dikes, and diversions. spring; therefore, grazing should be delayed until the soil is In summer, irrigation is needed for the maximum firm and the more desirable forage plants have achieved production of most forage crops. Because the rate of water enough growth to withstand grazing pressure. Compaction intake is rapid, sprinkler irrigation is the best method of can be minimized by grazing first in the areas that dry out applying water. This method permits an even, controlled earliest. application of water, helps to prevent excessive runoff, and Thinning, logging, and fire reduce the density of the minimizes the risk of erosion. To prevent overirrigation and overstory canopy and increase the production of the leaching of plant nutrients, applications of irrigation understory vegetation. Areas that support a large amount water should be adjusted to the available water capacity, of competing vegetation can be improved by prescribed the rate of water intake, and the needs of the crop. burning or by chemical or mechanical treatment. Seeding Because the soil is droughty, the applications should be disturbed areas to suitable plants increases forage light and frequent. production and reduces the risk of erosion. Maintaining a protective plant cover in winter reduces the The vegetative site is Mixed Fir-Serviceberry Forest. soil loss resulting from flooding. Proper stocking rates, pasture rotation, and restricted grazing during wet periods 21A-Camas sandy loam, 0 to 3 percent slopes. help to keep pastures in good condition and protect the soil This very deep, excessively drained soil is on flood plains. It from erosion. Grazing when the soil is wet results in formed in alluvium derived from mixed sources. Elevation is compaction of the surface layer, poor tilth, and excessive 1,000 to 3,000 feet. The mean annual precipitation is 18 to runoff. Periodic mowing and clipping help to maintain 40 inches, the mean annual temperature is 50 to 54 uniform plant growth, discourage selective grazing, and degrees F, and the average frost-free period is 150 to 180 reduce the extent of clumpy growth. Fertilizer is needed to days. The vegetation in areas that have not been cultivated ensure the optimum growth of grasses and legumes. is mainly hardwoods and an understory of grasses, shrubs, Grasses respond to nitrogen, and legumes respond to sulfur and forbs. and phosphorus. Typically, the surface layer is dark brown sandy loam Returning all crop residue to the soil and using a about 10 inches thick. The upper 9 inches of the substratum cropping system that includes grasses, legumes, or is very dark grayish brown very gravelly loamy sand. The grass-legume mixtures help to maintain fertility and tilth. lower part to a depth of 60 inches is very dark grayish Leaving crop residue on or near the surface helps to brown extremely gravelly coarse sand. In some areas the conserve moisture and control erosion. surface layer is gravelly or cobbly. This unit is poorly suited to homesite development. The main limitations are the flooding and the very rapid permeability in the substratum. This unit is poorly suited to standard systems of waste more than 3 percent. Included areas make up about 20 disposal because of a poor filtering capacity in the percent of the total acreage. extremely gravelly substratum and the hazard of flooding. Permeability is moderately rapid in the upper part of the Alternative waste disposal systems may function properly Camas soil and very rapid in the lower part. Available water on this unit. Suitable included soils are throughout the unit. capacity is about 3 inches. The effective rooting depth is 60 Onsite investigation is needed to locate such soils. Dikes inches or more. The substratum can restrict the penetration and channels that have outlets for floodwater can protect of roots, however, because of droughtiness. Runoff is slow, buildings and onsite sewage disposal systems from and the hazard of water erosion is slight. This soil is flooding. occasionally flooded for brief periods from November In some areas excavation for houses and access roads through May. exposes material that is highly susceptible to soil blowing. This unit is used mainly for hay and pasture. It also is Revegetating as soon as possible in disturbed areas around used for cultivated crops, such as small grain, and for construction sites helps to control soil blowing. Cutbanks homesite development. are not stable and are subject to slumping. To keep This unit is suited to hay and pasture. The main cutbanks from caving in, excavations may require special limitations are the flooding, droughtiness, and gravel on the retainer walls. surface, which may limit the use of equipment. The risk of Establishing plants in areas where the surface layer has flooding can be reduced by levees, dikes, and diversions. been removed is difficult. Mulching and applying fertilizer In summer, irrigation is needed for the maximum help to establish plants in cut areas. Topsoil can be production of most forage crops. Because the rate of water stockpiled and used to reclaim areas disturbed during intake is rapid, sprinkler irrigation is the best method of construction. In many areas it may be necessary to haul in applying water. This method permits an even, controlled topsoil for lawns and gardens. Because of droughtiness application of water, helps to prevent excessive runoff, and and a low amount of rainfall in summer, irrigation is needed minimizes the risk of erosion. To prevent overirrigation and in areas that support lawn grasses, shrubs, vines, shade the leaching of plant nutrients, applications of irrigation trees, or ornamental trees. water should be adjusted to the available water capacity, Roads and streets should be constructed above the the rate of water intake, and the needs of the crop. expected level of flooding. The risk of flooding has been Because the soil is droughty, the applications should be reduced in some areas by the construction of large dams light and frequent. and reservoirs upstream. Maintaining a protective plant cover in winter reduces the The vegetative site is Loamy Flood Plain, 18- to 30- soil loss resulting from flooding. Proper stocking rates, inch precipitation zone. pasture rotation, and restricted grazing during wet periods help to keep pastures in good condition and protect the soil 22A-Camas gravelly sandy loam, 0 to 3 percent from erosion. Grazing when the soil is wet results in slopes. This very deep, excessively drained soil is on flood compaction of the surface layer, poor tilth, and excessive plains. It formed in alluvium derived from mixed sources. runoff. Periodic mowing and clipping help to maintain Elevation is 1,000 to 3,000 feet. The mean annual uniform plant growth, discourage selective grazing, and precipitation is 18 to 40 inches, the mean annual reduce the extent of clumpy growth. Fertilizer is needed to temperature is 50 to 54 degrees F, and the average ensure the optimum growth of grasses and legumes. frost-free period is 150 to 180 days. The vegetation in areas Grasses respond to nitrogen, and legumes respond to sulfur that have not been cultivated is mainly hardwoods and an and phosphorus. understory of grasses, shrubs, and forbs. Returning all crop residue to the soil and using a Typically, the surface layer is dark brown gravelly cropping system that includes grasses, legumes, or sandy loam about 10 inches thick. The upper 9 inches of grass-legume mixtures help to maintain fertility and tilth. the substratum is very dark grayish brown very gravelly Leaving crop residue on or near the surface helps to loamy sand. The lower part to a depth of 60 inches is very conserve moisture and control erosion. dark grayish brown extremely gravelly coarse sand. In This unit is poorly suited to homesite development. The some areas the surface layer is very gravelly or cobbly. main limitations are the flooding and the very rapid Included in this unit are small areas of Riverwash; permeability in the substratum. Cove soils on concave slopes; Central Point, Medford, This unit is poorly suited to standard systems of waste and Takilma soils on terraces; Abin, Evans, and Newberg disposal because of a poor filtering capacity in the soils; and poorly drained soils. Also included are small extremely gravelly substratum and the hazard of areas of Camas soils that have slopes of flooding. Alternative waste disposal systems may function properly on this unit. Suitable included soils are very gravelly loamy sand. The lower part to a depth of 60 throughout the unit. Onsite investigation is needed to locate inches is very dark grayish brown extremely gravelly coarse such soils. Dikes and channels that have outlets for sand. In some areas the surface layer is very gravelly or floodwater can protect buildings and onsite sewage disposal cobbly. systems from flooding. Permeability is moderately rapid in the upper part of the In some areas excavation for houses and access roads Camas soil and very rapid in the lower part. Available water exposes material that is highly susceptible to soil blowing. capacity is about 3 inches. The effective rooting depth is 60 Revegetating as soon as possible in disturbed areas around inches or more. The substratum can restrict the penetration construction sites helps to control soil blowing. Cutbanks of roots, however, because of droughtiness. Runoff is slow, are not stable and are subject to slumping. To keep and the hazard of water erosion is slight. This soil is cutbanks from caving in, excavations may require special occasionally flooded for brief periods from November retainer walls. through May. In some areas the water table is within a depth Establishing plants is difficult in areas where the surface of 60 inches. layer has been removed and the extremely gravelly The Newberg soil is very deep and somewhat substratum exposed. Mulching and applying fertilizer help excessively drained. It formed in alluvium derived from to establish plants in cut areas. Topsoil can be stockpiled mixed sources. Typically, the surface layer is very dark and used to reclaim areas disturbed during construction. In grayish brown fine sandy loam about 17 inches thick. The many areas it may be necessary to haul in topsoil for lawns upper 13 inches of the substratum is dark brown sandy and gardens. Because of droughtiness and a low amount of loam. The next 12 inches is dark brown fine sand. The rainfall in summer, irrigation is needed in areas that support lower part to a depth of 60 inches is dark grayish brown lawn grasses, shrubs, vines, shade trees, or ornamental loamy sand. In some areas the surface layer is gravelly or trees. cobbly. Roads and streets should be constructed above the Permeability is moderately rapid in the upper part of the expected level of flooding. The risk of flooding has been Newberg soil and rapid in the lower part. Available water reduced in some areas by the construction of large dams capacity is about 8 inches. The effective rooting depth is 60 and reservoirs upstream. inches or more. The substratum can restrict the penetration The vegetative site is Loamy Flood Plain, 18- to 30- of roots, however, because of droughtiness. Runoff is slow, inch precipitation zone. and the hazard of water erosion is slight. This soil is occasionally flooded for brief periods from December 23A-Camas-Newberg-Evans complex, 0 to 3 through March. In some areas the water table is within a percent slopes. This map unit is on flood plains. depth of 60 inches. Elevation is 1,000 to 3,000 feet. The mean annual The Evans soil is very deep and well drained. It formed precipitation is 18 to 40 inches, the mean annual in alluvium derived from mixed sources. Typically, the temperature is 50 to 54 degrees F, and the average surface layer is very dark brown loam about 38 inches frost-free period is 150 to 180 days. The native thick. The substratum to a depth of 60 inches is dark brown vegetation is mainly hardwoods and an understory of loam. In some areas the surface layer is gravelly or cobbly. grasses, shrubs, and forbs. Permeability is moderate in the Evans soil. Available This unit is about 40 percent Camas soil, 30 percent water capacity is about 11 inches. The effective rooting Newberg soil, and 20 percent Evans soil. The components depth is 60 inches or more. Runoff is slow, and the hazard of this unit occur as areas so intricately intermingled that of water erosion is slight. This soil is occasionally flooded mapping them separately was not practical at the scale for brief periods from December through March. In some used. areas the water table is within a depth of 60 inches. Included in this unit are small areas of Riverwash; This unit is used mainly for wildlife habitat or for hay and Cove soils on concave slopes; Central Point, Medford, pasture. It also is used for homesite development. and Takilma soils on terraces; Abin soils; and poorly The main limitations in the areas used for hay and drained soils. Also included are small areas of Camas, pasture are the flooding, droughtiness, and gravel on the Newberg, and Evans soils that have slopes of more than 3 surface, which may limit the use of equipment. The risk of percent. Included areas make up about 10 percent of the flooding can be reduced by levees, dikes, and diversions. total acreage. In summer, irrigation is needed for the maximum The Camas soil is very deep and excessively drained. It production of most forage crops. Because of a moderately formed in alluvium derived from mixed sources. Typically, rapid rate of water intake in the Camas and the surface layer is dark brown gravelly sandy loam about 10 inches thick. The upper 9 inches of the substratum is very dark grayish brown Newberg soils, sprinkler irrigation is the best method of droughtiness and a low amount of rainfall in summer, applying water. This method permits an even, controlled irrigation is needed in areas that support lawn grasses, application of water, helps to prevent excessive runoff, and shrubs, vines, shade trees, or ornamental trees. minimizes the risk of erosion. To prevent overirrigation and Roads and streets should be constructed above the the leaching of plant nutrients, applications of irrigation expected level of flooding. The risk of flooding has been water should be adjusted to the available water capacity, reduced in some areas by the construction of large dams the rate of water intake, and the needs of the crop. Because and reservoirs upstream. the soils are droughty, the applications should be light and The vegetative site is Loamy Flood Plain, 18- to 30- frequent. inch precipitation zone. Maintaining a protective plant cover in winter reduces the soil loss resulting from flooding. Proper stocking rates, 24C-Campfour-Paragon complex, 1 to 12 percent pasture rotation, and restricted grazing during wet periods slopes. This map unit is on plateaus. Elevation is 3,000 to help to keep pastures in good condition and protect the soils 4,400 feet. The mean annual precipitation is 20 to 25 from erosion. Grazing when the soils are wet results in inches, the mean annual temperature is 45 to 51 degrees compaction of the surface layer, poor tilth, and excessive F, and the average frost-free period is 100 to 130 days. The runoff. Periodic mowing and clipping help to maintain native vegetation is mainly conifers and hardwoods and an uniform plant growth, discourage selective grazing, and understory of grasses, shrubs, and forbs. reduce the extent of clumpy growth. Fertilizer is needed to This unit is about 45 percent Campfour soil and 30 ensure the optimum growth of grasses and legumes. percent Paragon soil. The components of this unit occur as Grasses respond to nitrogen, and legumes respond to sulfur areas so intricately intermingled that mapping them and phosphorus. separately was not practical at the scale used. Returning all crop residue to the soils and using a Included in this unit are small areas of Rock outcrop; cropping system that includes grasses, legumes, or Carney, Randcore, Shoat, and Skookum soils; and soils grass-legume mixtures help to maintain fertility and tilth. that are similar to the Paragon soil but have more than 35 Leaving crop residue on or near the surface helps to percent hard rock fragments or have bedrock at a depth of conserve moisture and control erosion. more than 40 inches. Also included are small areas of This unit is poorly suited to homesite development. The Campfour and Paragon soils that have slopes of more than main limitations are the flooding and the rapid or very rapid 12 percent. Included areas make up about 25 percent of the permeability in the substratum of the Camas and Newberg total acreage. soils. The Campfour soil is very deep and well drained. It This unit is poorly suited to standard systems of waste formed in residuum and colluvium derived dominantly from disposal because of a poor filtering capacity in the andesite. Typically, the surface is covered with a layer of substratum of the Camas and Newberg soils and the needles and twigs about 1 inch thick. The surface layer is hazard of flooding. Alternative waste disposal systems dark reddish brown loam about 5 inches thick. The next may function properly on this unit. Suitable included soils layer is dark reddish brown loam about 16 inches thick. The are throughout the unit. Onsite investigation is needed to upper 29 inches of the subsoil is dark reddish brown clay locate such soils. Dikes and channels that have outlets for loam. The lower 10 inches is dark reddish brown gravelly floodwater can protect buildings and onsite sewage clay loam. The depth to bedrock is 60 inches or more. In disposal systems from flooding. some areas the surface layer is stony. In some areas excavation for houses and access roads Permeability is moderately slow in the Campfour soil. exposes material that is highly susceptible to soil blowing. Available water capacity is about 8 inches. The effective Revegetating as soon as possible in disturbed areas around rooting depth is 60 inches or more. Runoff is slow, and the construction sites helps to control soil blowing. Cutbanks hazard of water erosion is slight. are not stable and are subject to slumping. To keep The Paragon soil is moderately deep and well drained. It cutbanks from caving in, excavations may require special formed in residuum and colluvium derived dominantly from retainer walls. andesite. Typically, the surface is covered with a layer of Establishing plants is difficult in areas where the surface needles and twigs about 1 inch thick. The surface layer is layer has been removed. Mulching and applying fertilizer dark reddish brown cobbly loam about 3 inches thick. The help to establish plants in cut areas. Topsoil can be next 10 inches also is dark reddish brown cobbly loam. The stockpiled and used to reclaim areas disturbed during subsoil is dark reddish brown gravelly clay loam about 12 construction. In many areas it may be necessary to haul in inches thick. Weathered bedrock is at a depth of about 25 topsoil for lawns and gardens. Because of inches. The depth to bedrock ranges from 20 to 40 inches. In when the soils are least susceptible to compaction. some areas the surface layer is stony or very cobbly. Ripping skid trails and landings when the soils are dry can Permeability is moderately slow in the Paragon soil. improve the growth of plants. Available water capacity is about 3 inches. The effective Erosion can be controlled by carefully planning the rooting depth is 20 to 40 inches. Runoff is slow, and the construction and maintenance of logging roads, skid trails, hazard of water erosion is slight. and landings. Seeding, mulching, and benching areas that This unit is used for timber production, livestock have been cut and filled also help to control erosion. Skid grazing, and wildlife habitat. trails and unsurfaced roads may be impassable during This unit is suited to the production of Douglas fir and rainy periods. Logging roads require suitable surfacing for ponderosa pine. Other species that grow on this unit include year-round use. incense cedar and California black oak. The understory A high temperature in the surface layer and an vegetation includes tall Oregongrape, common snowberry, insufficient moisture supply in summer increase the and western fescue. seedling mortality rate. The large number of rock fragments On the basis of a 100-year site curve, the mean site in the Paragon soil also increases the seedling mortality index for Douglas fir is 110 on the Campfour soil. The yield rate. To compensate for the expected high mortality rate, at culmination of the mean annual increment is 5,880 cubic the larger seedlings or a greater number of seedlings feet per acre in a fully stocked, even-aged stand of trees at should be planted. When the timber is harvested, leaving 60 years and 48,300 board feet per acre (Scribner rule) at some of the larger trees unharvested provides shade for 140 years. On the basis of a 50-year curve, the mean site seedlings. Reforestation can be accomplished by planting index is 85. ponderosa pine and Douglas fir seedlings. On the basis of a 100-year site curve, the mean site Severe frost can damage or kill seedlings. Air index for ponderosa pine is 95 on the Campfour soil. The drainage may be restricted on this unit. Proper timber yield at culmination of the mean annual increment is 3,760 harvesting methods can reduce the effect of frost on cubic feet per acre in a fully stocked, even-aged stand of regeneration. trees at 40 years and 43,160 board feet per acre (Scribner The main limitation affecting livestock grazing is rule) at 130 years. compaction. The native vegetation suitable for grazing On the basis of a 100-year site curve, the mean site includes western fescue, tall trisetum and mountain index for Douglas fir is 85 on the Paragon soil. The yield at brome on the Campfour soil and Idaho fescue and culmination of the mean annual increment is 4,480 cubic bluegrass on the Paragon soil. If the understory is feet per acre in a fully stocked, even-aged stand of trees at overgrazed, the proportion of preferred forage plants 70 years and 27,520 board feet per acre (Scribner rule) at decreases and the proportion of less preferred forage 160 years. On the basis of a 50-year curve, the mean site plants increases. index is 60. A planned grazing system that includes timely deferment On the basis of a 100-year site curve, the mean site of grazing, rotation grazing, and proper livestock distribution index for ponderosa pine is 80 on the Paragon soil. The helps to prevent overgrazing of the understory and damage yield at culmination of the mean annual increment is 2,670 to the soils. Grazing should be delayed until the more cubic feet per acre in a fully stocked, even-aged stand of desirable forage plants have achieved enough growth to trees at 40 years and 33,750 board feet per acre (Scribner withstand grazing pressure and the soils are firm enough to rule) at 150 years. withstand trampling by livestock. The main limitations affecting timber production are Thinning, logging, and fire reduce the density of the compaction, erosion, and seedling mortality. Also, the overstory canopy and increase the production of bedrock underlying the Paragon soil restricts root growth. understory vegetation. Areas that support a large amount As a result, windthrow is a hazard. of competing vegetation can be improved by prescribed Conventional methods of harvesting timber generally are burning or by chemical or mechanical treatment. Seeding suitable, but the soils may be compacted if they are moist disturbed areas to suitable plants increases forage when heavy equipment is used. Puddling can occur when production and reduces the risk of erosion. the soils are wet. If the soils are excessively disturbed when The vegetative site in areas of the Campfour soil is timber is harvested or logging roads are built, a larger Douglas Fir-Mixed Pine-Sedge Forest, and the one in number of rock fragments is left on the surface. Using areas of the Paragon soil is Loamy Slopes, 18- to 24inch low-pressure ground equipment causes less damage to the precipitation zone. soils and helps to maintain productivity. Compaction can be minimized by using suitable methods of harvesting, laying out skid trails in advance, and harvesting timber 24E--Campfour-Paragon complex, 12 to 35 percent unit include incense cedar and California black oak. The slopes. This map unit is on hillslopes. It is commonly on understory vegetation includes tall Oregongrape, common south-facing slopes. Elevation is 3,000 to 4,400 feet. The snowberry, and western fescue. mean annual precipitation is 20 to 25 inches, the mean On the basis of a 100-year site curve, the mean site annual temperature is 45 to 51 degrees F, and the average index for Douglas fir is 110 on the Campfour soil. The yield frost-free period is 100 to 130 days. The native vegetation at culmination of the mean annual increment is 5,880 cubic is mainly conifers and hardwoods and an understory of feet per acre in a fully stocked, even-aged stand of trees at grasses, shrubs, and forbs. 60 years and 48,300 board feet per acre (Scribner rule) at This unit is about 45 percent Campfour soil and 30 140 years. On the basis of a 50-year curve, the mean site percent Paragon soil. The components of this unit occur as index is 85. areas so intricately intermingled that mapping them On the basis of a 100-year site curve, the mean site separately was not practical at the scale used. index for ponderosa pine is 95 on the Campfour soil. The Included in this unit are small areas of Rock outcrop; yield at culmination of the mean annual increment is 3,760 Carney, Randcore, Shoat, and Skookum soils; and soils cubic feet per acre in a fully stocked, even-aged stand of that are similar to the Paragon soil but have more than 35 trees at 40 years and 43,160 board feet per acre (Scribner percent hard rock fragments or have bedrock at a depth of rule) at 130 years. more than 40 inches. Also included are small areas of On the basis of a 100-year site curve, the mean site Campfour and Paragon soils that have slopes of less than index for Douglas fir is 85 on the Paragon soil. The yield at 12 or more than 35 percent. Included areas make up about culmination of the mean annual increment is 4,480 cubic 25 percent of the total acreage. feet per acre in a fully stocked, even-aged stand of trees at The Campfour soil is very deep and well drained. It 70 years and 27,520 board feet per acre (Scribner rule) at formed in colluvium derived dominantly from andesite. 160 years. On the basis of a 50-year curve, the mean site Typically, the surface is covered with a layer of needles and index is 60. twigs about 1 inch thick. The surface layer is dark reddish On the basis of a 100-year site curve, the mean site brown loam about 5 inches thick. The next layer is dark index for ponderosa pine is 80 on the Paragon soil. The reddish brown loam about 16 inches thick. The upper 29 yield at culmination of the mean annual increment is 2,670 inches of the subsoil is dark reddish brown clay loam. The cubic feet per acre in a fully stocked, even-aged stand of lower 10 inches is dark reddish brown gravelly clay loam. trees at 40 years and 33,750 board feet per acre (Scribner The depth to bedrock is 60 inches or more. In some areas rule) at 150 years. the surface layer is stony. The main limitations affecting timber production are Permeability is moderately slow in the Campfour soil. erosion, compaction, and seedling mortality. Also, the Available water capacity is about 8 inches. The effective bedrock underlying the Paragon soil restricts root growth. rooting depth is 60 inches or more. Runoff is medium, and As a result, windthrow is a hazard. the hazard of water erosion is moderate. Wheeled and tracked logging equipment can be used in The Paragon soil is moderately deep and well drained. It the less sloping areas, but cable yarding generally is safer in formed in colluvium derived dominantly from andesite. the more sloping areas and results in less surface Typically, the surface is covered with a layer of needles and disturbance. If the soils are excessively disturbed when twigs about 1 inch thick. The surface layer is dark reddish timber is harvested or logging roads are built, a larger brown cobbly loam about 3 inches thick. The next 10 number of rock fragments is left on the surface. Using inches also is dark reddish brown cobbly loam. The subsoil standard wheeled and tracked equipment when the soils are is dark reddish brown gravelly clay loam about 12 inches moist causes rutting and compaction. Puddling can occur thick. Weathered bedrock is at a depth of about 25 inches. when the soils are wet. Using low-pressure ground The depth to bedrock ranges from 20 to 40 inches. In some equipment causes less damage to the soils and helps to areas the surface layer is stony or very cobbly. maintain productivity. Compaction can be minimized by Permeability is moderately slow in the Paragon soil. using suitable methods of harvesting, laying out skid trails in Available water capacity is about 3 inches. The effective advance, and harvesting timber when the soils are least rooting depth is 20 to 40 inches. Runoff is medium, and the susceptible to compaction. Ripping skid trails and landings hazard of water erosion is moderate. when the soils are dry can improve the growth of plants. This unit is used for timber production, livestock Properly designed road drainage systems that include grazing, and wildlife habitat. carefully located culverts help to control erosion. Seeding, This unit is suited to the production of Douglas fir mulching, and benching areas that have been cut and filled and ponderosa pine. Other species that grow on this also help to control erosion. Steep yarding paths, skid trails, and firebreaks are subject to rilling and temperature is 46 to 54 degrees F, and the average gullying unless they are protected by a plant cover or frost-free period is 100 to 160 days. The native adequate water bars, or both. Skid trails and unsurfaced vegetation is mainly conifers and hardwoods and an roads may be impassable during rainy periods. Logging understory of grasses, shrubs, and forbs. roads require suitable surfacing for year-round use. This unit is about 60 percent Caris soil and 30 percent A high temperature in the surface layer and an Offenbacher soil. The components of this unit occur as insufficient moisture supply in summer increase the areas so intricately intermingled that mapping them seedling mortality rate. The large number of rock fragments separately was not practical at the scale used. in the Paragon soil also increases the seedling mortality Included in this unit are small areas of Tallowbox, rate. To compensate for the expected high mortality rate, Vannoy, and Voorhies soils; small areas of McMullin soils the larger seedlings or a greater number of seedlings and Rock outcrop on ridges and convex slopes; and, on should be planted. When the timber is harvested, leaving concave slopes, soils that are similar to the Caris and some of the larger trees unharvested provides shade for Offenbacher soils but have bedrock at a depth of more than seedlings. Reforestation can be accomplished by planting 40 inches. Also included are small areas of Caris and ponderosa pine and Douglas fir seedlings. Offenbacher soils that have slopes of less than 50 or more Severe frost can damage or kill seedlings in the less than 80 percent. Included areas make up about 10 percent sloping areas where air drainage may be restricted. Proper of the total acreage. timber harvesting methods can reduce the effect of frost on The Caris soil is moderately deep and well drained. It regeneration. formed in colluvium derived dominantly from metamorphic The main limitations affecting livestock grazing are rock. Typically, the surface is covered with a layer of compaction and erosion. The native vegetation suitable for needles and twigs about 1 inch thick. The surface layer is grazing includes western fescue, tall trisetum, and mountain very dark grayish brown gravelly loam about 7 inches thick. brome on the Campfour soil and Idaho fescue and The upper 13 inches of the subsoil is dark yellowish brown bluegrass on the Paragon soil. If the understory is very gravelly clay loam. The lower 11 inches is dark overgrazed, the proportion of preferred forage plants yellowish brown extremely gravelly loam. Bedrock is at a decreases and the proportion of less preferred forage depth of about 31 inches. The depth to bedrock ranges from plants increases. 20 to 40 inches. In some areas the surface layer is very A planned grazing system that includes timely deferment gravelly loam or is stony. of grazing, rotation grazing, and proper livestock distribution Permeability is moderate in the Caris soil. Available helps to prevent overgrazing of the understory and damage water capacity is about 2 inches. The effective rooting to the soils. Grazing should be delayed until the more depth is 20 to 40 inches. Runoff is rapid, and the hazard desirable forage plants have achieved enough growth to of water erosion is high. withstand grazing pressure and the soils are firm enough to The Offenbacher soil is moderately deep and well withstand trampling by livestock. drained. It formed in colluvium derived dominantly from Thinning, logging, and fire reduce the density of the metamorphic rock. Typically, the surface is covered with a overstory canopy and increase the production of layer of needles, leaves, and twigs about 1 inch thick. The understory vegetation. Areas that support a large amount surface layer is dark grayish brown and dark brown gravelly of competing vegetation can be improved by prescribed loam about 9 inches thick. The subsoil is reddish brown and burning or by chemical or mechanical treatment. Seeding yellowish red loam about 25 inches thick. Bedrock is at a disturbed areas to suitable plants increases forage depth of about 34 inches. The depth to bedrock ranges from production and reduces the risk of erosion. 20 to 40 inches. In some areas the surface layer is very The vegetative site in areas of the Campfour soil is gravelly loam or is stony. Douglas Fir-Mixed Pine-Sedge Forest, and the one in Permeability is moderate in the Offenbacher soil. areas of the Paragon soil is Loamy Slopes, 18- to 24inch Available water capacity is about 4 inches. The effective precipitation zone. rooting depth is 20 to 40 inches. Runoff is rapid, and the hazard of water erosion is high. 25G-Caris-Offenbacher gravelly loams, 50 to 80 This unit is used for timber production and wildlife percent north slopes. This map unit is on hillslopes. habitat. It is suited to the production of Douglas fir. Other Elevation is 1,000 to 4,000 feet. The mean annual species that grow on this unit include incense cedar, precipitation is 25 to 40 inches, the mean annual ponderosa pine, and Pacific madrone. The understory vegetation includes oceanspray, common snowberry, and tall Oregongrape. On the basis of a 100-year site curve, the mean site index for Douglas fir is 105 on the Caris soil. The yield at the seedling mortality rate. The large number of rock culmination of the mean annual increment is 5,460 cubic fragments in the soils also increases the seedling mortality feet per acre in a fully stocked, even-aged stand of trees rate. To compensate for the expected high mortality rate, at 60 years and 45,600 board feet per acre (Scribner rule) the larger seedlings or a greater number of seedlings should at 150 years. On the basis of a 50-year curve, the mean be planted. When the timber is harvested, leaving some of site index is 70. the larger trees unharvested provides shade for seedlings. On the basis of a 100-year site curve, the mean site Increased erosion, loss of plant nutrients, and water index for Douglas fir is 110 on the Offenbacher soil. The repellency are likely to result from fires of moderate yield at culmination of the mean annual increment is 5,880 intensity. cubic feet per acre in a fully stocked, even-aged stand of The vegetative site is Douglas Fir Forest. trees at 60 years and 48,300 board feet per acre (Scribner rule) at 140 years. On the basis of a 50-year curve, the 26G-Caris-Offenbacher gravelly loams, 50 to 75 mean site index is 75. percent south slopes. This map unit is on hillslopes. The main limitations affecting timber production are Elevation is 1,000 to 4,000 feet. The mean annual the slope, erosion, plant competition, and seedling precipitation is 25 to 40 inches, the mean annual mortality. Also, the bedrock restricts root growth. As a temperature is 46 to 54 degrees F, and the average result, windthrow is a hazard. frost-free period is 100 to 160 days. The native vegetation The slope restricts the use of wheeled and tracked is mainly conifers and hardwoods and an understory of logging equipment. High-lead or other cable systems are grasses, shrubs, and forbs. the best methods of logging. If the soils are excessively This unit is about 60 percent Caris soil and 20 percent disturbed when timber is harvested or logging roads Offenbacher soil. The components of this unit occur as are-built, a larger number of rock fragments is left on the areas so intricately intermingled that mapping them surface. Ripping landings when the soils are dry can separately was not practical at the scale used. improve the growth of plants. Included in this unit are small areas of Tallowbox, Properly designed road drainage systems that include Vannoy, and Voorhies soils; McMullin soils and Rock carefully located culverts help to control erosion. Road cuts outcrop on ridges and convex slopes; and, on concave can expose a large amount of fractured bedrock, which slopes, soils that are similar to the Caris and Offenbacher limits the response to seeding and mulching. Cut slopes are soils but have bedrock at a depth of more than 40 inches. subject to slumping where the bedrock is highly fractured or Also included are small areas of Caris and Offenbacher where rock layers are parallel to the slopes. Steep yarding soils that have slopes of less than 50 percent and more paths and firebreaks are subject to rilling and gullying than 75 percent. Included areas make up about 20 percent unless they are protected by a plant cover or adequate of the total acreage. water bars, or both. The Caris soil is moderately deep and well drained. It Building logging roads at midslope requires extensive formed in colluvium derived dominantly from metamorphic cutting and filling and removes land from production. rock. Typically, the surface is covered with a layer of Material that is discarded when the roads are built can needles and twigs about 1 inch thick. The surface layer is damage vegetation and is a potential source of very dark grayish brown gravelly loam about 7 inches thick. sedimentation. If the material becomes saturated, The upper 13 inches of the subsoil is dark yellowish brown avalanches of debris can occur. End hauling of the waste very gravelly clay loam. The lower 11 inches is dark material minimizes damage to the vegetation downslope yellowish brown extremely gravelly loam. Bedrock is at a and reduces the risk of sedimentation. Unsurfaced roads depth of about 31 inches. The depth to bedrock ranges from may be impassable during rainy periods. Logging roads 20 to 40 inches. In some areas the surface layer is very require suitable surfacing for year-round use. gravelly loam or is stony. Undesirable plants limit natural or artificial reforestation Permeability is moderate in the Caris soil. Available unless intensive site preparation and maintenance water capacity is about 2 inches. The effective rooting measures are applied. Reforestation can be accomplished depth is 20 to 40 inches. Runoff is rapid, and the hazard by planting Douglas fir and ponderosa pine seedlings. of water erosion is high. Mulching around seedlings helps to maintain the moisture The Offenbacher soil is moderately deep and well supply in summer and minimizes competition from drained. It formed in colluvium derived dominantly from undesirable understory plants. metamorphic rock. Typically, the surface is covered with a A high temperature in the surface layer during summer layer of needles, leaves, and twigs about 1 inch thick. The and the low available water capacity increase surface layer is dark grayish brown and dark brown gravelly loam about 9 inches thick. The subsoil is reddish sedimentation. If the material becomes saturated, brown and yellowish red loam about 25 inches thick. avalanches of debris can occur. End hauling of the Bedrock is at a depth of about 34 inches. The depth to waste material minimizes damage to the vegetation bedrock ranges from 20 to 40 inches. In some areas the downslope and reduces the risk of sedimentation. surface layer is very gravelly loam or is stony. Unsurfaced roads may be impassable during rainy Permeability is moderate in the Offenbacher soil. periods. Logging roads require suitable surfacing for Available water capacity is about 4 inches. The effective year-round use. rooting depth is 20 to 40 inches. Runoff is rapid, and the A high temperature in the surface layer during summer hazard of water erosion is high. and the low available water capacity increase the seedling This unit is used for timber production and wildlife mortality rate. The large number of rock fragments in the habitat. It is suited to the production of Douglas fir and soils also increases the seedling mortality rate. To ponderosa pine. Other species that grow on this unit compensate for the expected high mortality rate, the larger include incense cedar, California black oak, and Pacific seedlings or a greater number of seedlings should be madrone. The understory vegetation includes Pacific planted. When the timber is harvested, leaving some of the serviceberry, tall Oregongrape, and California fescue. larger trees unharvested provides shade for seedlings. The On the basis of a 100-year site curve, the mean site seedling mortality rate also can be reduced by providing index for Douglas fir is 100 on the Caris soil. The yield at artificial shade for seedlings. Reforestation can be culmination of the mean annual increment is 5,040 cubic accomplished by planting Douglas fir and ponderosa pine feet per acre in a fully stocked, even-aged stand of trees at seedlings. 60 years and 39,750 board feet per acre (Scribner rule) at Undesirable plants limit natural or artificial 150 years. On the basis of a 50-year curve, the mean site reforestation unless intensive site preparation and index is 65. maintenance measures are applied. Mulching around On the basis of a 100-year site curve, the mean site seedlings helps to maintain the moisture supply in index for Douglas fir is 105 on the Offenbacher soil. The summer and minimizes competition from undesirable yield at culmination of the mean annual increment is 5,460 understory plants. cubic feet per acre in a fully stocked, even-aged stand of Increased erosion, loss of plant nutrients, and water trees at 60 years and 45,600 board feet per acre (Scribner repellency are likely to result from fires of moderate rule) at 150 years. On the basis of a 50-year curve, the intensity. mean site index is 70. The vegetative site is Pine-Douglas Fir-Fescue. The main limitations affecting timber production are the slope, erosion, seedling mortality, and plant competition. 27B-Carney clay, 1 to 5 percent slopes. This Also, the bedrock restricts root growth. As a result, moderately deep, moderately well drained soil is on windthrow is a hazard. alluvial fans. It formed in alluvium derived dominantly from The slope restricts the use of wheeled and tracked tuff and breccia. Elevation is 1,200 to 4,000 feet. The logging equipment. High-lead or other cable systems are mean annual precipitation is 18 to 30 inches, the mean the best methods of logging. If the soils are excessively annual temperature is 48 to 54 degrees F, and the disturbed when timber is harvested or logging roads are average frost-free period is 150 to 180 days. The native built, a larger number of rock fragments is left on the vegetation is mainly hardwoods and an understory of surface. Ripping landings when the soils are dry can grasses, shrubs, and forbs. improve the growth of plants. Typically, the surface layer is dark brown clay about 6 Properly designed road drainage systems that include inches thick. The next layer also is dark brown clay about 6 carefully located culverts help to control erosion. Road cuts inches thick. The subsoil is dark brown clay about 23 can expose a large amount of fractured bedrock, which inches thick. Weathered bedrock is at a depth of about 35 limits the response to seeding and mulching. Cut slopes are inches. The depth to bedrock ranges from 20 to 40 inches. subject to slumping where the bedrock is highly fractured or In some areas the surface layer is cobbly or stony. where rock layers are parallel to the slopes. Steep yarding Included in this unit are small areas of Coker and paths and firebreaks are subject to rilling and gullying Phoenix soils on concave slopes, Cove and Padigan soils unless they are protected by a plant cover or adequate on concave slopes near drainageways, Brader and water bars, or both. Debenger soils on ridges and convex slopes, and Darow Building logging roads at midslope requires extensive and Manita soils. Also included are small areas of soils that cutting and filling and removes land from production. are similar to the Carney soil but have bedrock at a depth of Material that is discarded when the roads are built can more than 40 inches and Carney soils that have slopes of damage vegetation and is a potential source of more than 5 percent. Included areas make up about 20 percent of the total acreage. included soils are throughout the unit. Onsite Permeability is very slow in the Carney soil. Available investigation is needed to locate such soils. water capacity is about 4 inches. The effective rooting depth If buildings are constructed on this unit, properly is 20 to 40 inches. Runoff is slow, and the hazard of water designing foundations and footings, diverting runoff away erosion is slight. The water table fluctuates between depths from the buildings, and backfilling with material that has a of 3.0 and 3.5 feet from December through April. low shrink -swell potential help to prevent the structural This unit is used mainly for hay and pasture or for tree damage caused by shrinking and swelling. Properly fruit. It also is used for homesite development and designing buildings and roads helps to offset the limited livestock grazing. ability of the soil to support a load. Revegetating as soon This unit is suited to irrigated crops. It is limited mainly as possible helps to control erosion in disturbed areas by the high content of clay, a slow rate of water intake, and around construction sites. Topsoil can be stockpiled and droughtiness. In summer, irrigation is needed for the used to reclaim areas disturbed during construction. In maximum production of most crops. Sprinkler and trickle many areas it may be necessary to haul in topsoil for lawns irrigation systems are the best methods of applying water. and gardens. Because of a low amount of rainfall in These systems permit an even, controlled application of summer, irrigation is needed in areas that support lawn water, help to prevent excessive runoff, and minimize the grasses, shrubs, vines, shade trees, or ornamental trees. risk of erosion. Border and contour flood irrigation systems The main limitations affecting livestock grazing are also are suitable. For the efficient application and removal compaction, the clayey surface layer, and droughtiness. of surface irrigation water, land leveling is needed. Because The vegetation suitable for grazing includes Idaho fescue, of the very slow permeability, water applications should be bluebunch wheatgrass, and prairie junegrass. If the range is regulated so that the water does not stand on the surface overgrazed, the proportion of preferred forage plants and damage the crop. Land smoothing and open ditches decreases and the proportion of less preferred forage plants can reduce surface wetness. The use of pipe, ditch lining, increases. Grazing should be delayed until the more or drop structures in irrigation ditches reduces water loss desirable forage plants have achieved enough growth to and the hazard of erosion. withstand grazing pressure and the soil is firm enough to Solid-set sprinkler irrigation is the best method of withstand trampling by livestock. controlling frost and providing adequate moisture for tree Suitable management practices on this unit include fruit. Compaction can be minimized by limiting the use of proper grazing use, deferred grazing, rotation grazing, and equipment when the soil is wet. A permanent cover crop brush control. Areas that support a large amount of helps to control runoff and erosion. competing vegetation can be improved by chemical or This unit is well suited to permanent pasture. The high mechanical treatment. content of clay severely limits tillage and root growth. Deep Range seeding is suitable if the site is in poor condition. cracks form as the soil dries in summer. Proper stocking The main limitations are the clayey surface layer and rates, pasture rotation, and restricted grazing during wet droughtiness. The plants selected for seeding should be periods help to keep pastures in good condition and those that meet the seasonal requirements of livestock or protect the soil from erosion. Grazing when the soil is wet wildlife, or both. results in compaction of the surface layer, poor tilth, and This unit is limited as a site for livestock watering excessive runoff. Periodic mowing and clipping help to ponds and other water impoundments because of the maintain uniform plant growth, discourage selective depth to bedrock. grazing, and reduce the extent of clumpy growth. Fertilizer The vegetative site is Droughty Fan, 18- to 26-inch is needed to ensure the optimum growth of grasses and precipitation zone. legumes. Grasses respond to nitrogen, and legumes respond to sulfur and phosphorus. 27D-Carney clay, 5 to 20 percent slopes. This The main limitations affecting homesite development moderately deep, moderately well drained soil is on are the very slow permeability, a high shrink-swell alluvial fans and hillslopes. It formed in alluvium and potential, the depth to bedrock, and low strength. colluvium derived dominantly from tuff and breccia. This unit is poorly suited to standard systems of waste Elevation is 1,200 to 4,000 feet. The mean annual disposal because of the very slow permeability and the precipitation is 18 to 30 inches, the mean annual depth to bedrock. Alternative waste disposal systems temperature is 48 to 54 degrees F, and the average may function properly on this unit. Suitable frost-free period is 150 to 180 days. The native vegetation is mainly hardwoods and an understory of grasses, shrubs, and forbs. Typically, the surface layer is dark brown clay about 6 to maintain uniform plant growth, discourage selective inches thick. The next layer also is dark brown clay about 6 grazing, and reduce the extent of clumpy growth. Fertilizer is inches thick. The subsoil is dark brown clay about 23 needed to ensure the optimum growth of grasses and inches thick. Weathered bedrock is at a depth of about 35 legumes. Grasses respond to nitrogen, and legumes inches. The depth to bedrock ranges from 20 to 40 inches. respond to sulfur and phosphorus. In some areas the surface layer is cobbly or stony. The main limitations affecting homesite development Included in this unit are small areas of Coker and are the very slow permeability, a high shrink-swell Phoenix soils on concave slopes; Cove and Padigan soils potential, the depth to bedrock, the slope, and low on concave slopes near drainageways; and Rock outcrop strength. and Brader, Debenger, Darow, and Manita soils. Also This unit is poorly suited to standard systems of waste included are small areas of soils that are similar to the disposal because of the very slow permeability and the Carney soil but have bedrock at a depth of less than 20, or depth to bedrock. Alternative waste disposal systems more than 40 inches and Carney soils that have slopes of may function properly on this unit. Suitable included soils less than 5 or more than 20 percent. Included areas make are throughout the unit. Onsite investigation is needed to up about 20 percent of the total acreage. locate such soils. Permeability is very slow in the Carney soil. Available If buildings are constructed on this unit, properly water capacity is about 4 inches. The effective rooting depth designing foundations and footings, diverting runoff away is 20 to 40 inches. Runoff is slow or medium, and the hazard from the buildings, and backfilling with material that has a of water erosion is slight or moderate. The water table low shrink -swell potential help to prevent the struc tural fluctuates between depths of 3.0 and 3.5 feet from damage caused by shrinking and swelling. Properly December through April. designing buildings and roads helps to offset the limited This unit is used mainly for hay and pasture or for tree ability of the soil to support a load. fruit. It also is used for homesite development and Erosion is a hazard on the steeper slopes. Only the part livestock grazing. of the site that is used for construction should be disturbed. This unit is suited to irrigated crops. It is limited mainly by Revegetating as soon as possible helps to control erosion the high content of clay, a slow rate of water intake, the in disturbed areas around construction sites. Topsoil can slope, and droughtiness. In summer, irrigation is needed for be stockpiled and used to reclaim areas disturbed during the maximum production of most crops. Because of the construction. In many areas it may be necessary to haul in slope, sprinkler and trickle irrigation systems are suitable topsoil for lawns and gardens. Because of a low amount of methods of applying water. These systems permit an even, rainfall in summer, irrigation is needed in areas that support controlled application of water, help to prevent excessive lawn grasses, shrubs, vines, shade trees, or ornamental runoff, and minimize the risk of erosion. To prevent trees. overirrigation and excessive erosion, applications of The main limitations affecting livestock grazing are irrigation water should be adjusted to the available water compaction, erosion, the clayey surface layer, and capacity, the rate of water intake, and the needs of the crop. droughtiness. The vegetation suitable for grazing includes Solid-set sprinkler irrigation is the best method of Idaho fescue, bluebunch wheatgrass, and prairie junegrass. controlling frost and providing adequate moisture for tree If the range is overgrazed, the proportion of preferred fruit. Compaction can be minimized by limiting the use of forage plants decreases and the proportion of less equipment when the soil is wet. A permanent cover crop preferred forage plants increases. Grazing should be helps to control runoff and erosion. delayed until the more desirable forage plants have This unit is well suited to permanent pasture. The high achieved enough growth to withstand grazing pressure and content of clay severely limits tillage and root growth. Deep the soil is firm enough to withstand trampling by livestock. cracks form as the soil dries in summer. Seedbeds should Range seeding is suitable if the site is in poor condition. be prepared on the contour or across the slope where The main limitations are the clayey surface layer and practical. Proper stocking rates, pasture rotation, and droughtiness. The plants selected for seeding should be restricted grazing during wet periods help to keep pastures those that meet the seasonal requirements of livestock or in good condition and protect the soil from erosion. Grazing wildlife, or both. when the soil is wet results in compaction of the surface Suitable management practices on this unit include layer, poor tilth, and excessive runoff. Periodic mowing and proper grazing use, deferred grazing, rotation grazing, and clipping help brush control. Areas that support a large amount of competing vegetation can be improved by chemical or mechanical treatment. This unit is limited as a site for livestock watering cobbly clay and droughtiness. The plants selected for ponds and other water impoundments because of the seeding should be those that meet the seasonal slope and the depth to bedrock. requirements of livestock or wildlife, or both. The vegetative site is Droughty Fan, 18- to 26-inch Suitable management practices on this unit include precipitation zone. proper grazing use, deferred grazing, rotation grazing, and brush control. Areas that support a large amount of 28D-Carney cobbly clay, 5 to 20 percent slopes. competing vegetation can be improved by chemical or This moderately deep, moderately well drained soil is on mechanical treatment. In places the use of ground alluvial fans and hillslopes. It formed in alluvium and equipment is limited by the cobbles on the surface. colluvium derived dominantly from tuff and breccia. This unit is limited as a site for livestock watering Elevation is 1,200 to 4,000 feet. The mean annual ponds and other water impoundments because of the precipitation is 18 to 30 inches, the mean annual slope and the depth to bedrock. temperature is 48 to 54 degrees F, and the average This unit is suited to permanent pasture. It is limited frost-free period is 150 to 180 days. The native vegetation mainly by the high content of clay, a slow rate of water is mainly hardwoods and an understory of grasses, shrubs, intake, the cobbly surface layer, and the slope. The high and forbs. content of clay and cobbles in the surface layer severely Typically, the surface layer is dark brown cobbly clay limits tillage and root growth. Deep cracks form as the soil about 6 inches thick. The next layer is dark brown clay dries in summer. about 6 inches thick. The subsoil also is dark brown clay. It In summer, irrigation is needed for the maximum is about 23 inches thick. Weathered bedrock is at a depth production of most forage crops. Because of the slope, of about 35 inches. The depth to bedrock ranges from 20 to sprinkler irrigation is the best method of applying water. This 40 inches. In some areas the surface layer is stony. method permits an even, controlled application of water, Included in this unit are small areas of Coker and helps to prevent excessive runoff, and minimizes the risk of Phoenix soils on concave slopes; Cove and Padigan soils erosion. To prevent overirrigation and excessive erosion, on concave slopes near drainageways; Rock outcrop; applications of irrigation water should be adjusted to the Brader, Debenger, and Darow soils; and soils that are available water capacity, the rate of water intake, and the similar to the Carney soil but have bedrock at a depth of needs of the crop. less than 20 or more than 40 inches. Also included are small Seedbeds should be prepared on the contour or across areas of Carney soils that have slopes of less than 5 or the slope where practical. Proper stocking rates, pasture more than 20 percent. Included areas make up about 20 rotation, and restricted grazing during wet periods help to percent of the total acreage. keep pastures in good condition and protect the soil from Permeability is very slow in the Carney soil. Available erosion. Grazing when the soil is wet results in compaction of water capacity is about 4 inches. The effective rooting depth the surface layer, poor tilth, and excessive runoff. Periodic is 20 to 40 inches. Runoff is slow or medium, and the mowing and clipping help to maintain uniform plant growth, hazard of water erosion is slight or moderate. The water discourage selective grazing, and reduce the extent of table fluctuates between depths of 3.0 and 3.5 feet from clumpy growth. Fertilizer is needed to ensure the optimum December through April. growth of grasses and legumes. Grasses respond to This unit is used mainly for livestock grazing or for hay nitrogen, and legumes respond to sulfur and phosphorus. and pasture. It also is used for homesite development. The main limitations affecting homesite development are The main limitations affecting livestock grazing are the very slow permeability, a high shrink-swell potential, the compaction, erosion, the surface layer of cobbly clay, and depth to bedrock, low strength, and the slope. droughtiness. The vegetation suitable for grazing includes This unit is poorly suited to standard systems of waste Idaho fescue, bluebunch wheatgrass, and prairie junegrass. disposal because of the very slow permeability and the If the range is overgrazed, the proportion of preferred forage depth to bedrock. Alternative waste disposal systems may plants decreases and the proportion of less preferred forage function properly on this unit. Suitable included soils are plants increases. Grazing should be delayed until the more throughout the unit. Onsite investigation is needed to desirable forage plants have achieved enough growth to locate such soils. withstand grazing pressure and the soil is firm enough to If buildings are constructed on this unit, properly withstand trampling by livestock. designing foundations and footings, diverting runoff away Range seeding is suitable if the site is in poor condition. from the buildings, and backfilling with material that has a The main limitations are the surface layer of low shrink -swell potential help to prevent the structural damage caused by shrinking and swelling. Properly designing buildings and roads helps to offset the compaction, erosion, the surface layer of cobbly clay, limited ability of the soil to support a load. droughtiness, and the slope. The vegetation suitable for Erosion is a hazard on the steeper slopes. Only the part grazing includes Idaho fescue, bluebunch wheatgrass, and of the site that is used for construction should be disturbed. Lemmon needlegrass. If the range is overgrazed, the Revegetating as soon as possible helps to control erosion proportion of preferred forage plants decreases and the in disturbed areas around construction sites. Removal of proportion of less preferred forage plants increases. cobbles in disturbed areas is needed for the best results in Grazing should be delayed until the more desirable forage landscaping, particularly in areas used for lawns. Topsoil plants have achieved enough growth to withstand grazing can be stockpiled and used to reclaim areas disturbed pressure and the soil is firm enough to withstand trampling during construction. In many areas it may be necessary to by livestock. haul in topsoil for lawns and gardens. Because of a low Range seeding is suitable if the site is in poor condition. amount of rainfall in summer, irrigation is needed in areas The main limitations are the surface layer of cobbly clay, that support lawn grasses, shrubs, vines, shade trees, or the slope, and droughtiness. The plants selected for ornamental trees. seeding should be those that meet the seasonal The vegetative site is Droughty Fan, 18- to 26-inch requirements of livestock or wildlife, or both. precipitation zone. Suitable management practices on this unit include proper grazing use, deferred grazing, rotation grazing, and 28E-Carney cobbly clay, 20 to 35 percent slopes. brush control. Areas that support a large amount of This moderately deep, moderately well drained soil is on competing vegetation can be improved by chemical or alluvial fans and hillslopes. It formed in alluvium and mechanical treatment. In places the use of ground colluvium derived dominantly from tuff and breccia. equipment and access by livestock are limited by the Elevation is 1,200 to 4,000 feet. The mean annual cobbles on the surface and the slope. precipitation is 18 to 30 inches, the mean annual This unit is limited as a site for livestock watering temperature is 48 to 54 degrees F, and the average ponds and other water impoundments because of the frost-free period is 150 to 180 days. The native vegetation slope and the depth to bedrock. is mainly grasses, shrubs, and forbs. The main limitations affecting homesite development Typically, the surface layer is dark brown cobbly clay are the very slow permeability, a high shrink-swell about 6 inches thick. The next layer is dark brown clay potential, the depth to bedrock, the slope, and low strength. about 6 inches thick. The subsoil also is dark brown clay. It This unit is poorly suited to standard systems of waste is about 23 inches thick. Weathered bedrock is at a depth of disposal because of the very slow permeability, the depth about 35 inches. The depth to bedrock ranges from 20 to to bedrock, and the slope. Alternative waste disposal 40 inches. In some areas the surface layer is stony. systems may function properly on this unit. Suitable Included in this unit are small areas of Coker and included soils are throughout the unit. Onsite investigation Phoenix soils on concave slopes; Cove and Padigan soils is needed to locate such soils. on concave slopes near drainageways; Rock outcrop; and The slope limits the use of the steeper areas of this unit Brader, Debenger, Darow, and Manita soils. Also included for building site development. Cuts needed to provide are small areas of Heppsie soils on the steeper parts of the essentially level building sites can expose bedrock. landscape, soils that are similar to the Carney soil but have Properly designing foundations and footings, diverting bedrock at a depth of less than 20 or more than 40 inches, runoff away from the buildings, and backfilling with material and Carney soils that have slopes of less than 20 or more that has a low shrink-swell potential help to prevent the than 35 percent. Included areas make up about 20 percent structural damage caused by shrinking and swelling. of the total acreage. Properly designing buildings and roads helps to offset the Permeability is very slow in the Carney soil. Available limited ability of the soil to support a load. water capacity is about 4 inches. The effective rooting depth Erosion is a hazard on the steeper slopes. Only the part is 20 to 40 inches. Runoff is medium, and the hazard of of the site that is used for construction should be disturbed. water erosion is moderate. The water table fluctuates Revegetating as soon as possible helps to control erosion between depths of 3.0 and 3.5 feet from December through in disturbed areas around construction sites. Removal of April. cobbles in disturbed areas is needed for the best results in This unit is used for livestock grazing or homesite landscaping, particularly in areas used for lawns. Topsoil development. can be stockpiled and used to reclaim areas disturbed The main limitations affecting livestock grazing are during construction. In many areas it may be necessary to haul in topsoil for lawns and gardens. Because of a low amount of rainfall in the seasonal wetness, seedling mortality, and plant summer, irrigation is needed in areas that support lawn competition. Also, the bedrock restricts root growth. As a grasses, shrubs, vines, shade trees, or ornamental trees. result, windthrow is a hazard. The vegetative site is Droughty Foothill Slopes, 18- to Conventional methods of harvesting timber generally 22-inch precipitation zone. are suitable, but the seasonal high water table and the clayey surface layer limit the use of equipment to dry 29D-Carney cobbly clay, high precipitation, 5 to 20 periods. The soil may be compacted if it is moist when percent slopes. This moderately deep, moderately well heavy equipment is used. Puddling can occur when the soil drained soil is on hillslopes. It formed in alluvium and is wet. Using low-pressure ground equipment causes less colluvium derived dominantly from tuff and breccia. damage to the soil and helps to maintain productivity. Elevation is 2,400 to 4,000 feet. The mean annual Compaction can be minimized by using suitable methods of precipitation is 30 to 35 inches, the mean annual harvesting, laying out skid trails in advance, and harvesting temperature is 45 to 54 degrees F, and the average timber when the soil is least susceptible to compaction. frost-free period is 120 to 150 days. The native vegetation Ripping skid trails and landings when the soil is dry can is mainly hardwoods and conifers and an understory of improve the growth of plants. grasses, shrubs, and forbs. Properly designed road drainage systems that include Typically, the surface layer is dark brown cobbly clay carefully located culverts help to control erosion. Seeding, about 6 inches thick. The next layer is dark brown clay mulching, and benching areas that have been cut and filled about 6 inches thick. The subsoil also is dark brown clay. It also help to control erosion. Steep yarding paths, skid trails, is about 23 inches thick. Weathered bedrock is at a depth and firebreaks are subject to rilling and gullying unless they of about 35 inches. The depth to bedrock ranges from 20 to are protected by a plant cover or adequate water bars, or 40 inches. In some areas the surface layer is stony. both. Included in this unit are small areas of Rock outcrop and This unit is subject to severe slumping. Road failure and McMullin soils on ridges and convex slopes, Coker soils on landslides are likely to occur after road construction. concave slopes, Medco soils, and soils that are similar to Slumping can be minimized by constructing logging roads the Carney soil but have bedrock at a depth of more than in the less sloping areas, on better suited soils if practical, 40 inches. Also included are small areas of Carney soils and by installing properly designed road drainage systems. that have slopes of less than 5 or more than 20 percent. When wet or moist, unsurfaced roads and skid trails are Included areas make up about 20 percent of the total sticky. They may be impassable during rainy periods. acreage. Logging roads require suitable surfacing for year-round Permeability is very slow in the Carney soil. Available use. water capacity is about 4 inches. The effective rooting depth A high temperature in the surface layer during summer is 20 to 40 inches. Runoff is slow or medium, and the and the low available water capacity increase the seedling hazard of water erosion is slight or moderate. The water mortality rate. Shrinking and swelling can damage roots or table fluctuates between depths of 3.0 and 3.5 feet from push seedlings out of the ground. To compensate for the December through April. expected high mortality rate, the larger seedlings or a This unit is used mainly for livestock grazing or greater number of seedlings should be planted. The wildlife habitat. It also is used for limited timber seedling mortality rate can be reduced by providing production. artificial shade for seedlings. Reforestation can be This unit is poorly suited to the production of ponderosa accomplished by planting ponderosa pine seedlings. pine. Other species that grow on this unit include Oregon Undesirable plants, especially grasses, limit natural or white oak and California black oak. The understory artificial reforestation unless intensive site preparation and vegetation includes poison-oak, California oatgrass, and maintenance measures are applied. Mulching around Idaho fescue. seedlings helps to maintain the moisture supply in On the basis of a 100-year site curve, the mean site summer and minimizes competition from undesirable index for ponderosa pine is 70. The yield at culmination of understory plants. the mean annual increment is 2,750 cubic feet per acre in a The main limitations affecting livestock grazing are fully stocked, even-aged stand of trees at 50 years and compaction and erosion. The native vegetation suitable for 27,520 board feet per acre (Scribner rule) at 160 years. grazing includes California oatgrass, Idaho fescue, and The main limitations affecting timber production are bluegrass. If the understory is overgrazed, the proportion of compaction, erosion, slumping, the clayey surface layer, preferred forage plants decreases and the proportion of less preferred forage plants increases. A planned grazing system that includes timely deferment ponderosa pine. Other species that grow on this unit of grazing, rotation grazing, and proper livestock distribution include Oregon white oak and California black oak. The helps to prevent overgrazing of the understory and damage understory vegetation includes poison-oak, California to the soil. Grazing should be delayed until the more oatgrass, and Idaho fescue. desirable forage plants have achieved enough growth to On the basis of a 100-year site curve, the mean site withstand grazing pressure and the soil is firm enough to index for ponderosa pine is 70. The yield at culmination of withstand trampling by livestock. the mean annual increment is 2,750 cubic feet per acre in a Thinning, logging, and fire reduce the density of the fully stocked, even-aged stand of trees at 50 years and overstory canopy and increase the production of understory 27,520 board feet per acre (Scribner rule) at 160 years. vegetation. Areas that support a large amount of competing The main limitations affecting timber production are vegetation can be improved by chemical or mechanical erosion, compaction, slumping, the clayey surface layer, treatment. Seeding disturbed areas to suitable plants seasonal wetness, the slope, seedling mortality, and plant increases forage production and reduces the risk of erosion. competition. Also, the bedrock restricts root growth. As a The vegetative site is Clayey Hills, 20- to 35-inch result, windthrow is a hazard. precipitation zone. The seasonal high water table and the clayey surface layer limit the use of equipment to dry periods. Wheeled and 29E-Carney cobbly clay, high precipitation, 20 to 35 tracked logging equipment can be used in the less sloping percent slopes. This moderately deep, moderately well areas, but cable yarding generally is safer in the more drained soil is on hillslopes. It formed in alluvium and sloping areas and results in less surface disturbance. Using colluvium derived dominantly from tuff and breccia. standard wheeled and tracked equipment when the soil is Elevation is 2,400 to 4,000 feet. The mean annual moist causes rutting and compaction. Puddling can occur precipitation is 30 to 35 inches, the mean annual when the soil is wet. Using low-pressure ground equipment temperature is 45 to 54 degrees F, and the average causes less damage to the soil and helps to maintain frost-free period is 120 to 150 days. The native vegetation productivity. Compaction can be minimized by using suitable is mainly hardwoods and conifers and an understory of methods of harvesting, laying out skid trails in advance, and grasses, shrubs, and forbs. harvesting timber when the soil is least susceptible to Typically, the surface layer is dark brown cobbly clay compaction. Ripping skid trails and landings when the soil is about 6 inches thick. The next layer is dark brown clay dry can improve the growth of plants. about 6 inches thick. The subsoil also is dark brown clay. It Properly designed road drainage systems that include is about 23 inches thick. Weathered bedrock is at a depth of carefully located culverts help to control erosion. Seeding, about 35 inches. The depth to bedrock . ranges from 20 to mulching, and benching areas that have been cut and filled 40 inches. In some areas the surface layer is stony. also help to control erosion. Steep yarding paths, skid trails, Included in this unit are small areas of Rock outcrop and and firebreaks are subject to rilling and gullying unless they McMullin soils on ridges and convex slopes, Coker soils on are protected by a plant cover or adequate water bars, or concave slopes, and Medco soils. Also included are small both. areas of Heppsie soils on the steeper parts of the This unit is subject to severe slumping. Road failure and landscape, soils that are similar to the Carney soil but have landslides are likely to occur after road construction. bedrock at a depth of more than 40 inches, and Carney soils Slumping can be minimized by constructing logging roads that have slopes of less than 20 or more than 35 percent. in the less sloping areas, on better suited soils if practical, Included areas make up about 20 percent of the total and by installing properly designed road drainage systems. acreage. When wet or moist, unsurfaced roads and skid trails are Permeability is very slow in the Carney soil. Available sticky. They may be impassable during rainy periods. water capacity is about 4 inches. The effective rooting depth Logging roads require suitable surfacing for year-round is 20 to 40 inches. Runoff is medium, and the hazard of use. water erosion is moderate. The water table fluctuates A high temperature in the surface layer during summer between depths of 3.0 and 3.5 feet from December through and the low available water capacity increase the seedling April. mortality rate. Shrinking and swelling can damage roots or This unit is used mainly for livestock grazing or push seedlings out of the ground. To compensate for the wildlife habitat. It also is used for limited timber expected high mortality rate, the larger seedlings or a production. greater number of seedlings should be planted. The This unit is poorly suited to the production of seedling mortality rate can be reduced by providing artificial shade for seedlings. Reforestation can be accomplished by planting Included areas make up about 20 percent of the total ponderosa pine seedlings. acreage. Undesirable plants, especially grasses, limit natural or The Carney soil is moderately deep and moderately well artificial reforestation unless intensive site preparation and drained. It formed in alluvium and colluvium derived maintenance measures are applied. Mulching around dominantly from tuff and breccia. Typically, the surface layer seedlings helps to maintain the moisture supply in is dark brown cobbly clay about 6 inches thick. The next summer and minimizes competition from undesirable layer is dark brown clay about 6 inches thick. The subsoil understory plants. also is dark brown clay. It is about 23 inches thick. The main limitations affecting livestock grazing are Weathered bedrock is at a depth of about 35 inches. The compaction and erosion. The native vegetation suitable for depth to bedrock ranges from 20 to 40 inches. In some grazing includes California oatgrass, Idaho fescue, and areas the surface layer is stony. bluegrass. If the understory is overgrazed, the proportion of Permeability is very slow in the Carney soil. Available preferred forage plants decreases and the proportion of water capacity is about 4 inches. The effective rooting depth less preferred forage plants increases. is 20 to 40 inches. Runoff is medium, and the hazard of A planned grazing system that includes timely deferment water erosion is moderate. The water table fluctuates of grazing, rotation grazing, and proper livestock distribution between depths of 3.0 and 3.5 feet from December through helps to prevent overgrazing of the understory and damage April. to the soil. Grazing should be delayed until the more The Tablerock soil is very deep and moderately well desirable forage plants have achieved enough growth to drained. It formed in colluvium derived dominantly from tuff, withstand grazing pressure and the soil is firm enough to breccia, andesite, and sandstone. Typically, the surface is withstand trampling by livestock. covered with a layer of leaves and twigs about 1 1/2 inches Thinning, logging, and fire reduce the density of the thick. The surface layer is very dark brown gravelly loam overstory canopy and increase the production of understory about 3 inches thick. The next layer is very dark grayish vegetation. Areas that support a large amount of competing brown very cobbly clay loam about 7 inches thick. The vegetation can be improved by chemical or mechanical upper 10 inches of the subsoil is dark brown very cobbly treatment. Seeding disturbed areas to suitable plants clay loam. The next 18 inches is brown very cobbly clay. increases forage production and reduces the risk of erosion. The lower 27 inches is dark yellowish brown gravelly clay The vegetative site is Clayey Hills, 20- to 35-inch loam and gravelly loam. Weathered bedrock is at a depth of precipitation zone. about 65 inches. The depth to bedrock is 60 inches or more. In some areas the surface layer is cobbly or stony. 30E-Carney-Tablerock complex, 20 to 35 percent Permeability is very slow in the Tablerock soil. Available slopes. This map unit is on alluvial fans and hillslopes. water capacity is about 7 inches. The effective rooting depth Elevation is 1,250 to 3,600 feet. The mean annual is 60 inches or more. Runoff is medium, and the hazard of precipitation is 18 to 30 inches, the mean annual water erosion is moderate. The water table fluctuates temperature is 45 to 52 degrees F, and the average between depths of 4 and 6 feet from December through frost-free period is 120 to 180 days. The native vegetation April. is mainly grasses, shrubs, and forbs. This unit is used for livestock grazing and This unit is about 45 percent Carney soil and 35 recreational development. percent Tablerock soil. The components of this unit occur The main limitations affecting livestock grazing are the as areas so intricately intermingled that mapping them cobbly surface layer of the Carney soil, compaction, erosion, separately was not practical at the scale used. the slope, droughtiness, and the included areas of Rock Included in this unit are small areas of Coker and outcrop. The vegetation suitable for grazing includes Idaho Phoenix soils on concave slopes; Cove and Padigan soils fescue, bluebunch wheatgrass, and Lemmon needlegrass. If on concave slopes near drainageways; Rock outcrop; and the range is overgrazed, the proportion of preferred forage Brader, Debenger, and Darow soils. Also included are small plants decreases and the proportion of less preferred forage areas of soils that are similar to the Carney soil but have plants increases. Grazing should be delayed until the more bedrock at a depth of less than 20 or more than 40 inches, desirable forage plants have achieved enough growth to soils that are similar to the Tablerock soil but have bedrock withstand grazing pressure and the soils are firm enough to within a depth of 60 inches, and Carney and Tablerock soils withstand trampling by livestock. that have slopes of less than 20 or more than 35 percent. Range seeding is suitable if the site is in poor condition. The main limitations are the surface layer of cobbly clay in the Carney soil, the slope, droughtiness, soils; and soils that are similar to the Central Point soil but and the included areas of Rock outcrop. The plants have very gravelly layers below a depth of 30 inches. Also selected for seeding should be those that meet the included are small areas of Central Point soils that have seasonal requirements of livestock or wildlife, or both. slopes of more than 3 percent. Included areas make up Suitable management practices on this unit include about 20 percent of the total acreage. proper grazing use, deferred grazing, rotation grazing, and Permeability is moderately rapid in the Central Point brush control. Areas that support a large amount of soil. Available water capacity is about 6 inches. The competing vegetation can be improved by chemical or effective rooting depth is 60 inches or more. Runoff is mechanical treatment. In places the use of ground slow, and the hazard of water erosion is slight. The water equipment and access by livestock are limited by the slope, table fluctuates between depths of 4 and 6 feet from the cobbles on the surface, and the included areas of Rock December through March. outcrop. This unit is used mainly for irrigated crops, such as This unit is limited as a site for livestock watering grass seed, onions, alfalfa, and tree fruit. Other crops ponds and other water impoundments because of the include strawberries, small grain, and sugar beet seed. slope of both soils and the depth to bedrock in the Some areas are used for homesite development or Carney soil. pasture. If this unit is used for recreational development, the main This unit is well suited to irrigated crops. It has few limitations are the high content of clay, the surface layer of limitations. In summer, irrigation is needed for the maximum cobbly clay in the Carney soil, the slope, and the included production of most crops. Furrow, border, corrugation, areas of Rock outcrop. The Rock outcrop should be avoided trickle, and sprinkler irrigation systems are suitable. The unless it is to be highlighted in the development. system used generally is governed by the crop that is Revegetating as soon as possible helps to control erosion in grown. For the efficient application and removal of surface disturbed areas around construction sites. A plant cover can irrigation water, land leveling is needed. To prevent be established and maintained through applications of overirrigation and the leaching of plant nutrients, fertilizer and through seeding, mulching, and shaping of the applications of irrigation water should be adjusted to the slopes. Gravel and cobbles should be removed, particularly available water capacity, the rate of water intake, and the in picnic areas and on playgrounds. The soils are sticky and needs of the crop. Because the soil is droughty, the plastic when wet. As a result, trafficability is restricted. applications should be light and frequent. The use of pipe, The vegetative site in areas of the Carney soil is ditch lining, or drop structures in irrigation ditches reduces Droughty Foothill Slopes, 18- to 22-inch precipitation water loss and the hazard of erosion. zone, and the one in areas of the Tablerock soil is Returning all crop residue to the soil and using a Droughty Fan, 18- to 26-inch precipitation zone. cropping system that includes grasses, legumes, or grass-legume mixtures help to maintain fertility and tilth. 31A-Central Point sandy loam, 0 to 3 percent Leaving crop residue on or near the surface helps to slopes. This very deep, well drained soil is on stream conserve moisture and control erosion. terraces. It formed in alluvium derived dominantly from A tillage pan forms easily if this unit is tilled when wet. granitic and metamorphic rock. Elevation is 1,000 to 2,000 Chiseling or subsoiling breaks up the pan. Surface crusting feet. The mean annual precipitation is 18 to 40 inches, the and compaction can be minimized by returning crop mean annual temperature is 50 to 54 degrees F, and the residue to the soil. average frost-free period is 140 to 180 days. The Solid-set sprinkler irrigation is the best method of vegetation in areas that have not been cultivated is mainly controlling frost and providing adequate moisture for tree grasses and forbs. fruit. Compaction can be minimized by limiting the use of Typically, the surface layer is black and very dark brown equipment when the soil is wet. A permanent cover crop sandy loam about 30 inches thick. The upper 12 inches of helps to control runoff and erosion. the subsoil is very dark grayish brown sandy loam. The Proper stocking rates, pasture rotation, and restricted lower 7 inches is dark brown sandy loam. The upper 10 grazing during wet periods help to keep pastures in good inches of the substratum is dark brown gravelly sandy condition and protect the soil from erosion. Grazing when loam. The lower part to a depth of 67 inches is dark brown the soil is wet results in compaction of the surface layer, gravelly loamy sand. poor tilth, and excessive runoff. Periodic mowing and Included in this unit are small areas of Evans, Newberg, clipping help to maintain uniform plant growth, discourage and Camas soils on flood plains; Barron soils on the higher selective grazing, and reduce the extent of clumpy growth. parts of the landscape; Gregory and Clawson soils on Fertilizer is needed to ensure the optimum growth of concave slopes; Kubli and Medford grasses and legumes. Grasses respond to nitrogen, and legumes respond to production of most forage crops. Sprinkler irrigation is the sulfur and phosphorus. best method of applying water. This method permits an This unit is well suited to homesite development. It has even, controlled application of water, helps to prevent few limitations. Cutbanks are not stable and are subject to excessive runoff, and minimizes the risk of erosion. Border slumping. To keep cutbanks from caving in, excavations and contour flood irrigation systems also are suitable. For may require special retainer walls. Revegetating as soon as the efficient application and removal of surface irrigation possible helps to control erosion in disturbed areas around water, land leveling is needed. To prevent overirrigation and construction sites. Topsoil can be stockpiled and used to the leaching of plant nutrients, applications of irrigation reclaim areas disturbed during construction. Because of a water should be adjusted to the available water capacity, low amount of rainfall and droughtiness in summer, the rate of water intake, and the needs of the crop. The use irrigation is needed in areas that support lawn grasses, of pipe, ditch lining, or drop structures in irrigation ditches shrubs, vines, shade trees, or ornamental trees. reduces water loss and the hazard of erosion. The vegetative site is Deep Loamy Terrace, 18- to Wetness limits the choice of suitable forage plants and 28-inch precipitation zone. the period of cutting or grazing and increases the risk of winterkill. Proper stocking rates, pasture rotation, and 32B-Clawson sandy loam, 2 to 5 percent slopes. restricted grazing during wet periods help to keep pastures This very deep, poorly drained soil is on alluvial fans. It in good condition and protect the soil from erosion. Grazing formed in alluvium derived dominantly from granitic rock. when the soil is wet results .in compaction of the surface Elevation is 1,000 to 1,300 feet. The mean annual layer, poor tilth, and excessive runoff. Periodic mowing and precipitation is 30 to 35 inches, the mean annual clipping help to maintain uniform plant growth, discourage temperature is 52 to 54 degrees F, and the average selective grazing, and reduce the extent of clumpy growth. frost-free period is 140 to 170 days. The vegetation in areas Fertilizer is needed to ensure the optimum growth of that have not been cultivated is mainly grasses, sedges, grasses and legumes. Grasses respond to nitrogen, and and forbs. legumes respond to sulfur and phosphorus. Typically, the surface layer is very dark grayish brown This unit is limited as a site for livestock watering sandy loam about 10 inches thick. The subsoil is dark ponds and other water impoundments because of grayish brown sandy loam about 35 inches thick. The seepage. substratum to a depth of 60 inches is dark grayish brown The main limitations affecting homesite development and grayish brown sandy loam. In some areas the surface are wetness in winter and spring and the moderately rapid layer is gravelly. permeability. Included in this unit are small areas of Barron and This unit is poorly suited to standard systems of waste Shefflein soils on convex slopes and on the higher parts of disposal because of the wetness. Interceptor ditches can the landscape; Central Point, Kubli, and Medford soils; and divert subsurface water and thus improve the efficiency of soils that are similar to the Clawson soil but have gravelly the absorption fields. Alternative waste disposal systems layers within a depth of 40 inches. Also included are small may function properly on this unit. Suitable included soils areas of Clawson soils that have slopes of more than 5 are throughout the unit. Onsite investigation is needed to percent. Included areas make up about 20 percent of the locate such soils. total acreage. Because of the seasonal high water table, a drainage Permeability is moderately rapid in the Clawson soil. system is needed on sites for buildings with basements and Available water capacity is about 7 inches. The effective crawl spaces. The wetness can be reduced by installing rooting depth is limited by the water table, which is at a drainage tile around footings. Revegetating as soon as depth of 1 to 3 feet from November through June. Runoff is possible helps to control erosion in disturbed areas around slow, and the hazard of water erosion is slight. construction sites. Topsoil can be stockpiled and used to This unit is used for hay and pasture or for homesite reclaim areas disturbed during construction. Because of development. droughtiness and a low amount of rainfall in summer, This unit is suited to hay and pasture. The main irrigation is needed in areas that support lawn grasses, limitations are wetness in winter and spring and shrubs, vines, shade trees, or ornamental trees. droughtiness in summer and fall. Tile drainage can lower Cutbanks are not stable and are subject to slumping. To the water table if a suitable outlet is available. Land keep cutbanks from caving in, excavations may require smoothing and open ditches can reduce surface wetness. special retainer walls. In summer, irrigation is needed for the maximum The vegetative site is Semi-Wet Meadow. 33A-Coker clay, 0 to 3 percent slopes. This very deep, tree fruit. Compaction can be minimized by limiting the use somewhat poorly drained soil is on alluvial fans. It formed in of equipment when the soil is wet. A permanent cover alluvium derived dominantly from tuff and breccia. Elevation crop helps to control runoff and erosion. is 1,200 to 4,000 feet. The mean annual precipitation is 18 This unit is well suited to permanent pasture. Wetness to 30 inches, the mean annual temperature is 46 to 54 limits the choice of suitable forage plants and the period of degrees F, and the average frost-free period is 120 to 180 cutting or grazing and increases the risk of winterkill. The days. The native vegetation is mainly grasses, sedges, and high content of clay severely limits tillage and root growth. forbs. Deep cracks form as the soil dries in summer. Proper Typically, the surface layer is very dark gray clay about stocking rates, pasture rotation, and restricted grazing 20 inches thick. The next layer is very dark gray and dark during wet periods help to keep pastures in good condition grayish brown, calcareous clay about 26 inches thick. The and protect the soil from erosion. Grazing when the soil is subsoil to a depth of 70 inches is dark grayish brown, wet results in compaction of the surface layer, poor tilth, and calcareous clay. The depth to bedrock is 60 inches or more. excessive runoff. Periodic mowing and clipping help to Included in this unit are small areas of Brader, Carney, maintain uniform plant growth, discourage selective grazing, Darow, and Debenger soils on convex slopes; Cove, and reduce the extent of clumpy growth. Fertilizer is needed Gregory, and Padigan soils on concave slopes near to ensure the optimum growth of grasses and legumes. drainageways; Medford and Phoenix soils and soils that Grasses respond to nitrogen, and legumes respond to sulfur are similar to the Coker soil but have bedrock at a depth of and phosphorus. 40 to 60 inches. Also included are small areas of Coker The main limitations affecting livestock grazing are soils that have slopes of more than 3 percent. Included compaction, the clayey surface layer, wetness in winter and areas make up about 20 percent of the total acreage. spring, and droughtiness in summer and fall. The Permeability is very slow in the Coker soil. Available vegetation suitable for grazing includes California oatgrass, water capacity is about 9 inches. The effective rooting bluegrass, and sedge. If the range is overgrazed, the depth is limited by the water table, which is at a depth of proportion of preferred forage plants decreases and the 0.5 foot to 1.5 feet from December through April. Runoff is proportion of less preferred forage plants increases. slow, and the hazard of water erosion is slight. Because this soil remains wet for long periods in spring, This unit is used mainly for hay and pasture or for grazing should be delayed until the more desirable forage tree fruit. It also is used for livestock grazing, small plants have achieved enough growth to withstand grazing grain, and homesite development. pressure and the soil is firm enough to withstand trampling This unit is suited to irrigated crops. It is limited mainly by livestock. Compaction can be minimized by grazing first by the high content of clay, a slow rate of water intake, in the areas that dry out earliest. wetness in winter and spring, and droughtiness in summer Range seeding is suitable if the site is in poor condition. and fall. Crops that require good drainage can be grown if a The main limitations are the clayey surface layer, wetness in properly designed drainage system is installed. The ability winter and spring, and droughtiness in summer and fall. The of tile drains to remove subsurface water from the soil is plants selected for seeding should be those that meet the limited because of the very slow permeability. seasonal requirements of livestock or wildlife, or both. In summer, irrigation is needed for the maximum Suitable management practices on this unit include production of most crops. Sprinkler and trickle irrigation proper grazing use, deferred grazing, rotation grazing, and systems are suitable. Border and contour flood systems brush control. Areas that support a large amount of also are suitable. For the efficient application and removal competing vegetation can be improved by chemical or of surface irrigation water, land leveling is needed. Because mechanical treatment. of the very slow permeability and the water table, water This unit is suited to livestock watering ponds and applications should be regulated so that the water does not other water impoundments. stand on the surface and damage the crop. Land smoothing The main limitations affecting homesite development are and open ditches can reduce surface wetness. The use of the wetness, a high shrink-swell potential, the very slow pipe, ditch lining, or drop structures in irrigation ditches permeability, and low strength. reduces water loss and the hazard of erosion. This unit is poorly suited to standard systems of waste Solid-set sprinkler irrigation is the best method of disposal because of the wetness and the very slow controlling frost and providing adequate moisture for permeability. Alternative waste disposal systems may function properly on this unit. Suitable included soils are in some areas of the unit. Onsite investigation is mainly by the high content of clay, a slow rate of water needed to locate such soils. intake, wetness in winter and spring, droughtiness in A drainage system is needed if roads or building summer and fall, and the slope. Crops that require good foundations are constructed on this unit. The wetness can drainage can be grown if a properly designed tile drainage be reduced by installing drainage tile around footings. system is installed. The ability of tile drains to remove Properly designing foundations and footings, diverting subsurface water from the soil is limited because of the very runoff away from the buildings, and backfilling with material slow permeability. that has a low shrink-swell potential help to prevent the In summer, irrigation is needed for the maximum structural damage caused by shrinking and swelling. production of most crops. Because of the slope, sprinkler Properly designing buildings and roads helps to offset the and trickle irrigation systems are the best methods of limited ability of the soil to support a load. applying water. These systems permit an even, controlled Revegetating as soon as possible helps to control . application of water, help to prevent excessive runoff, and erosion in disturbed areas around construction sites. In minimize the risk of erosion. Border and contour flood many areas it may be necessary to haul in topsoil for lawns irrigation systems also are suitable in the less sloping areas. and gardens. Because of a low amount of rainfall in For the efficient application and removal of surface irrigation summer, irrigation is needed in areas that support lawn water, land leveling is needed. To prevent overirrigation and grasses, shrubs, vines, shade trees, or ornamental trees. excessive erosion, applications of irrigation water should be The vegetative site is Semi-Wet Meadow. adjusted to the available water capacity, the rate of water intake, and the needs of the crop. The use of pipe, ditch 33C-Coker clay, 3 to 12 percent slopes. This very lining, or drop structures in irrigation ditches reduces water deep, somewhat poorly drained soil is on alluvial fans. It loss and the hazard of erosion. formed in alluvium derived dominantly from tuff and breccia. Solid-set sprinkler irrigation is the best method of Elevation is 1,200 to 4,000 feet. The mean annual controlling frost and providing adequate moisture for tree precipitation is 18 to 30 inches, the mean annual fruit. Compaction can be minimized by limiting the use of temperature is 46 to 54 degrees F, and the average equipment when the soil is wet. Growing a permanent frost-free period is 120 to 180 days. The native vegetation is cover crop helps to control runoff and reduces the hazard mainly grasses, sedges, and forbs. of erosion. Typically, the surface layer is very dark gray clay about This unit is well suited to permanent pasture. Wetness 20 inches thick. The next layer is very dark gray and dark limits the choice of suitable forage plants and the period of grayish brown, calcareous clay about 26 inches thick. The cutting or grazing and increases the risk of winterkill. The subsoil to a depth of 70 inches is dark grayish brown, high content of clay severely limits tillage and root growth. calcareous clay. The depth to bedrock is 60 inches or more. Deep cracks form as the soil dries in summer. Proper Included in this unit are small areas of Brader, Carney, stocking rates, pasture rotation, and restricted grazing Darow, and Debenger soils on convex slopes; Cove, during wet periods help to keep pastures in good condition Gregory, and Padigan soils on concave slopes near and protect the soil from erosion. Grazing when the soil is drainageways; Medford and Phoenix soils; and soils that wet results in compaction of the surface layer, poor tilth, and are similar to the Coker soil but have bedrock at a depth of excessive runoff. Periodic mowing and clipping help to 40 to 60 inches. Also included are small areas of Coker maintain uniform plant growth, discourage selective grazing, soils that have slopes of less than 3 or more than 12 and reduce the extent of clumpy growth. Fertilizer is needed percent. Included areas make up about 20 percent of the to ensure the optimum growth of grasses and legumes. total acreage. Grasses respond to nitrogen, and legumes respond to sulfur Permeability is very slow in the Coker soil. Available and phosphorus. water capacity is about 9 inches. The effective rooting The main limitations affecting livestock grazing are depth is limited by the water table, which is at a depth of compaction, erosion, the clayey surface layer, wetness in 0.5 foot to 1.5 feet from December through April. Runoff is winter and spring, and droughtiness in summer and fall. slow, and the hazard of water erosion is slight. The vegetation suitable for grazing includes California This unit is used mainly for hay and pasture or for oatgrass, bluegrass, and sedge. If the range is overgrazed, tree fruit. It also is used for livestock grazing, small grain, the proportion of preferred forage plants decreases and the and homesite development. proportion of less preferred forage plants increases. This unit is suited to irrigated crops. It is limited Because this soil remains wet for long periods in spring, grazing should be delayed until the soil is firm and the more desirable forage plants have achieved cultivated is mainly hardwoods and an understory of enough growth to withstand grazing pressure. grasses, shrubs, and forbs. Compaction can be minimized by grazing first in the Typically, the surface layer is dark brown loam about 8 areas that dry out earliest. inches thick. The next layer is dark brown clay loam about Range seeding is suitable if the site is in poor 12 inches thick. The subsoil is dark brown clay about 20 condition. The main limitations are the clayey surface inches thick. The upper 18 inches of the substratum is dark layer, wetness in winter and spring, and droughtiness in brown clay loam. The lower part to a depth of 65 inches is summer and fall. The plants selected for seeding should yellowish red clay loam. The depth to bedrock is 60 inches be those that meet the seasonal requirements of or more. In some areas the surface layer is gravelly. livestock or wildlife, or both. Suitable management practices on this unit include Included in this unit are small areas of Gregory and proper grazing use, deferred grazing, rotation grazing, Medford soils on the lower terraces and Ruch soils on and brush control. Areas that support a large amount of alluvial fans. Also included are small areas of Coleman competing vegetation can be improved by chemical or soils that have slopes of more than 7 percent. Included mechanical treatment. areas make up about 15 percent of the total acreage. This unit is limited as a site for livestock watering Permeability is slow in the Coleman soil. Available water ponds and other water impoundments because of the capacity is about 10 inches. The effective rooting depth is slope. 60 inches or more. Runoff is slow, and the hazard of water The main limitations affecting homesite development erosion is slight. The water table fluctuates between depths are the wetness, a high shrink -swell potential, the very of 1.5 and 2.0 feet from December through April. slow permeability, and low strength. This unit is poorly suited to standard systems of This unit is used mainly for irrigated crops, such as alfalfa waste disposal because of the wetness and the very hay, tree fruit, and small grain. Other crops include corn for slow permeability. Alternative waste disposal systems silage and sugar beet seed. Some areas are used for may function properly on this unit. Suitable included homesite development, grass hay, or pasture. soils are in some areas of the unit. Onsite investigation is needed to locate such soils. This unit is suited to irrigated crops. It is limited mainly A drainage system is needed if roads or building by wetness in winter and spring and by the slow foundations are constructed on this unit. The wetness permeability. Crops that require good drainage can be can be reduced by installing drainage tile around grown if a properly designed tile drainage system is footings. Properly designing foundations and footings, installed. Tile drainage can lower the water table if diverting runoff away from the buildings, and backfilling collection laterals are closely spaced and a suitable outlet with material that has a low shrink -swell potential help is available. In the less sloping areas, land smoothing and to prevent the structural damage caused by shrinking open ditches can reduce surface wetness. and swelling. Properly designing buildings and roads helps to offset the limited ability of the soil to support a In summer, irrigation is needed for the maximum load. production of most crops. Furrow, border, corrugation, Revegetating as soon as possible helps to control trickle, and sprinkler irrigation systems are suitable. The erosion in disturbed areas around construction sites. In system used generally is governed by the crop that is many areas it may be necessary to haul in topsoil for grown. For the efficient application and removal of lawns and gardens. Because of a low amount of rainfall surface irrigation water, land leveling is needed. To in summer, irrigation is needed in areas that support prevent overirrigation, development of a perched water lawn grasses, shrubs, vines, shade trees, or ornamental table, and an increase in the risk of erosion, applications of trees. irrigation water should be adjusted to the available water The vegetative site is Semi-Wet Meadow. capacity, the rate of water intake, and the needs of the crop. The use of pipe, ditch lining, or drop structures in irrigation 34B-Coleman loam, 0 to 7 percent slopes. This very ditches reduces water loss and the hazard of erosion. deep, moderately well drained soil is on stream terraces. It Returning all crop residue to the soil and using a formed in alluvium derived dominantly from sedimentary cropping system that includes grasses, legumes, or and volcanic rock. Elevation is 1,200 to 1,700 feet. The grass-legume mixtures help to maintain fertility and tilth. mean annual precipitation is 18 to 25 inches, the mean Leaving crop residue on or near the surface helps to annual temperature is 50 to 54 degrees F, and the conserve moisture and control erosion. average frost-free period is 160 to 180 days. The vegetation in areas that have not been A tillage pan forms easily if the soil is tilled when wet. Chiseling or subsoiling breaks up the pan. Surface crusting 35A-Cove clay, 0 to 3 percent slopes. This very deep, and compaction can be minimized by returning crop poorly drained soil is on flood plains. It formed in alluvium residue to the soil. derived dominantly from tuff and breccia. Elevation is Solid-set sprinkler irrigation is the best method of 1,200 to 2,500 feet. The mean annual precipitation is 18 to controlling frost and providing adequate moisture for tree 30 inches, the mean annual temperature is 50 to 54 fruit. Compaction can be minimized by limiting the use of degrees F, and the average frost-free period is 140 to 180 equipment when the soil is wet and by planting a cover days. The native vegetation is mainly grasses, sedges, and crop. Growing a permanent cover crop helps to control forbs. runoff and reduces the hazard of erosion. Typically, the surface layer is black clay about 16 inches Proper stocking rates, pasture rotation, and restricted thick. The subsoil is very dark grayish brown silty clay grazing during wet periods help to keep pastures in good about 34 inches thick. The substratum to a depth of 60 condition and protect the soil from erosion. Grazing when inches is dark grayish brown silty clay. The depth to the soil is wet results in compaction of the surface layer, bedrock is 60 inches or more. In some areas the surface poor tilth, and excessive runoff. Periodic mowing and layer is silty clay loam. clipping help to maintain uniform plant growth, discourage Included in this unit are small areas of Carney soils on selective grazing, and reduce the extent of clumpy growth. convex slopes; Coker, Gregory, and Padigan soils; and Fertilizer is needed to ensure the optimum growth of soils that are similar to the Cove soil but are very gravelly grasses and legumes. Grasses respond to nitrogen, and within a depth of 30 inches. Also included are small areas of legumes respond to sulfur and phosphorus. Cove soils that have slopes of more than 3 percent. The main limitations affecting homesite development Included areas make up about 10 percent of the total are the wetness, the slow permeability, a high shrink-swell acreage. potential, and low strength. Permeability is very slow in the Cove soil. Available The slow permeability and the water table increase the water capacity is about 9 inches. The effective rooting possibility that septic tank absorption fields will fail. depth is limited by the water table, which is within a depth of Interceptor ditches can divert subsurface water and thus 1 foot from December through June. Runoff is slow, and the improve the efficiency of the absorption fields. Alternative hazard of water erosion is slight. This soil is frequently waste disposal systems may function properly on this unit. flooded for brief periods from December through April. Suitable included soils are throughout the unit. Onsite This unit is used mainly for pasture. It also is used for investigation is needed to locate such soils. tree fruit, grass-legume hay, and homesite development. A seasonal high water table is perched above the layer This unit is suited to permanent pasture. It is limited of clay; therefore, a drainage system is needed on sites for mainly by the hazard of flooding, the wetness, the high buildings with basements and crawl spaces. The wetness content of clay, and a slow rate of water intake. The risk of can be reduced by installing drainage tile around footings. flooding can be reduced by levees, dikes, and diversions. Properly designing foundations and footings, diverting runoff The ability of tile drains to remove subsurface water from the away from the buildings, and backfilling with material that soil is limited because of the very slow permeability. has a low shrink-swell potential help to prevent the In summer, irrigation is needed for the maximum structural damage caused by shrinking and swelling. production of most forage crops. Sprinkler irrigation is the Properly designing buildings and roads helps to offset the best method of applying water. Border and contour flood limited ability of the subsoil to support a load. irrigation systems also are suitable. For the efficient Revegetating as soon as possible helps to control application and removal of surface irrigation water, land erosion in disturbed areas around construction sites. leveling is needed. Because of the very slow permeability Topsoil can be stockpiled and used to reclaim areas and the seasonal high water table, water applications should disturbed during construction. In many areas it may be be regulated so that the water does not stand on the surface necessary to haul in topsoil for lawns and gardens. and damage the crop. Land smoothing and open ditches Because of a low amount of rainfall in summer, irrigation is can reduce surface wetness. The use of pipe, ditch lining, or needed in areas that support lawn grasses, shrubs, vines, drop structures in irrigation ditches reduces water loss and shade trees, or ornamental trees. the hazard of erosion. The vegetative site is Loamy Hills, 20- to 35-inch Wetness limits the choice of suitable forage plants precipitation zone. and the period of cutting or grazing and increases the risk 36G-Coyata -Rock outcrop complex, 35 to 80 of winterkill. Maintaining a protective plant cover in winter percent north slopes. This map unit is on hillslopes. reduces the soil loss resulting from flooding. The high Elevation is 2,000 to 4,000 feet. The mean annual content of clay severely limits tillage and root growth. Deep precipitation is 40 to 50 inches, the mean annual cracks form as the soil dries in summer. Proper stocking temperature is 45 to 52 degrees F, and the average rates, pasture rotation, and restricted grazing during wet frost-free period is 100 to 160 days. The native periods help to keep pastures in good condition and protect vegetation is mainly conifers and hardwoods and an the soil from erosion. Grazing when the soil is wet results in understory of grasses, shrubs, and forbs. compaction of the surface layer, poor tilth, and excessive This unit is about 50 percent Coyata soil and 30 runoff. Periodic mowing and clipping help to maintain percent Rock outcrop. The components of this unit occur uniform plant growth, discourage selective grazing, and as areas so intricately intermingled that mapping them reduce the extent of clumpy growth. Fertilizer is needed to separately was not practical at the scale used. ensure the optimum growth of grasses and legumes. Included in this unit are small areas of Crater Lake, Grasses respond to nitrogen, and legumes respond to Dumont, and Reinecke soils on the less sloping parts of the sulfur and phosphorus. landscape; soils that are similar to the Coyata soil but have Solid-set sprinkler irrigation is the best method of bedrock at a depth of more than 40 inches; and Coyata controlling frost and providing adequate moisture for tree soils that have slopes of less than 35 or more than 80 fruit. Compaction can be minimized by limiting the use of percent. Included areas make up about 20 percent of the equipment when the soil is wet and by planting a cover total acreage. crop. A permanent sod crop helps to control runoff. The Coyata soil is moderately deep and well drained. It This unit is poorly suited to homesite development. formed in colluvium derived dominantly from andesite. The main limitations are the flooding, the wetness, a high Typically, the surface is covered with a layer of needles, shrink-swell potential, and the very slow permeability. leaves, and twigs about 11/2 inches thick. The surface layer This unit is poorly suited to standard systems of waste is dark reddish brown very stony loam about 11 inches thick. disposal because of the hazard of flooding, the wetness, The next layer is dark brown very cobbly clay loam about 10 and the very slow permeability. Alternative waste inches thick. The subsoil is dark brown extremely cobbly disposal systems may function properly on this unit. clay loam about 10 inches thick. Bedrock is at a depth of Suitable included soils are throughout the unit. Onsite about 31 inches. The depth to bedrock ranges from 20 to 40 investigation is needed to locate such soils. inches. A drainage system is needed if roads or building Permeability is moderate in the Coyata soil. Available foundations are constructed on this unit. The wetness can water capacity is about 2 inches. The effective rooting depth be reduced by installing drainage tile around footings. is 20 to 40 inches. Runoff is rapid, and the hazard of water Properly designing foundations and footings, diverting erosion is high. runoff away from the buildings, and backfilling with material Rock outcrop consists of areas of exposed bedrock. that has a low shrink-swell potential help to prevent the Runoff is very rapid in these areas. structural damage caused by shrinking and swelling. This unit is used for timber production and wildlife Properly designing buildings and roads helps to offset the habitat. It is suited to the production of Douglas fir. Other limited ability of the soil to support a load. Roads and species that grow on this unit include white fir, western streets should be constructed above the expected level of hemlock, and golden chinkapin. The understory vegetation flooding. includes vine maple, California hazel, and cascade Revegetating as soon as possible helps to control Oregongrape. erosion in disturbed areas around construction sites. In On the basis of a 100-year site curve, the mean site many areas it may be necessary to haul in topsoil for lawns index for Douglas fir is 130 on the Coyata soil. The yield at and gardens. Because of a low amount of rainfall in culmination of the mean annual increment is 7,740 cubic summer, irrigation is needed in areas that support lawn feet per acre in a fully stocked, even-aged stand of trees at grasses, shrubs, vines, shade trees, or ornamental trees. 60 years and 58,520 board feet per acre (Scribner rule) at The vegetative site is Poorly Drained Bottom. 110 years. On the basis of a 50-year curve, the mean site index is 100. The main limitations affecting timber production are the slope, the Rock outcrop, erosion, plant competition, and seedling mortality. Also, the bedrock restricts root growth. As a result, windthrow is a hazard. frost-free period is 100 to 160 days. The native The slope restricts the use of wheeled and tracked vegetation is mainly conifers and hardwoods and an logging equipment. High-lead or other cable systems are understory of grasses, shrubs, and forbs. the best methods of logging. The Rock outcrop can cause This unit is about 50 percent Coyata soil and 30 percent breakage of falling timber and can hinder yarding. If the soil Rock outcrop. The components of this unit occur as areas is excessively disturbed when timber is harvested or so intricately intermingled that mapping them separately logging roads are built, a larger number of rock fragments was not practical at the scale used. is left on the surface. Ripping landings when the soil is dry Included in this unit are small areas of Crater Lake, can improve the growth of plants. Dumont, and Reinecke soils on the less sloping parts of the Properly designed road drainage systems that include landscape; soils that are similar to the Coyata soil but have carefully located culverts help to control erosion. Road cuts bedrock at a depth of more than 40 inches; and Coyata soils can expose a large amount of fractured bedrock, which that have slopes of less than 35 or more than 80 percent. limits the response to seeding and mulching. Steep yarding Included areas make up about 20 percent of the total paths and firebreaks are subject to rilling and gullying acreage. unless they are protected by a plant cover or adequate The Coyata soil is moderately deep and well drained. It water bars, or both. formed in colluvium derived dominantly from andesite. Building logging roads at midslope requires extensive Typically, the surface is covered with a layer of needles, cutting and filling and removes land from production. leaves, and twigs about 1 1/2 inches thick. The surface layer Material that is discarded when the roads are built can is dark reddish brown very stony loam about 11 inches thick. damage vegetation and is a potential source of The next layer is dark brown very cobbly clay loam about 10 sedimentation. If the material becomes saturated, inches thick. The subsoil is dark brown extremely cobbly avalanches of debris can occur. End hauling of the waste clay loam about 10 inches thick. Bedrock is at a depth of material minimizes damage to the vegetation downslope about 31 inches. The depth to bedrock ranges from 20 to 40 and reduces the risk of sedimentation. Skid trails and inches. unsurfaced roads may be impassable during rainy periods. Permeability is moderate in the Coyata soil. Available Logging roads require suitable surfacing for year-round use. water capacity is about 2 inches. The effective rooting depth Undesirable plants limit natural or artificial reforestation is 20 to 40 inches. Runoff is rapid, and the . hazard of water unless intensive site preparation and maintenance erosion is high. measures are applied. Reforestation can be accomplished Rock outcrop consists of areas of exposed bedrock. by planting Douglas fir and ponderosa pine seedlings. Runoff is very rapid in these areas. Mulching around seedlings helps to maintain the moisture This unit is used for timber production and wildlife supply in summer and minimizes competition from habitat. It is suited to the production of Douglas fir. Other undesirable understory plants. species that grow on this unit include white fir, incense A high temperature in the surface layer during summer cedar, and Pacific madrone. The understory vegetation and the low available water capacity increase the seedling includes Pacific serviceberry, tall Oregongrape, and mortality rate. The large number of rock fragments in the western fescue. soil also increases the seedling mortality rate. To On the basis of a 100-year site curve, the mean- site compensate for the expected high mortality rate, the larger index for Douglas fir is 120 on the Coyata soil. The yield at seedlings or a greater number of seedlings should be culmination of the mean annual increment is 6,900 cubic planted. When the timber is harvested, leaving some of the feet per acre in a fully stocked, even-aged stand of trees at larger trees unharvested provides shade for seedlings. 60 years and 52,440 board feet per acre (Scribner rule) at Because of the slope and the Rock outcrop, areas of 120 years. On the basis of a 50-year curve, the mean site this unit can hinder livestock movement. index is 90. The vegetative site is Mixed Fir-Western Hemlock The main limitations affecting timber production are the Forest. slope, the Rock outcrop, erosion, seedling mortality, and plant competition. Also, the bedrock restricts root growth. As 37G-Coyata -Rock outcrop complex, 35 to 80 a result, windthrow is a hazard. percent south slopes. This map unit is on hillslopes. The slope restricts the use of wheeled and tracked Elevation is 2,000 to 4,000 feet. The mean annual logging equipment. High-lead or other cable systems are precipitation is 40 to 50 inches, the mean annual the best methods of logging. The Rock outcrop can cause temperature is 45 to 52 degrees F, and the average breakage of falling timber and can hinder yarding. If the soil is excessively disturbed when timber is harvested or logging roads are built, a larger number of rock fragments is left on the surface. Ripping landings when the soil is dry can improve the growth of Coyata, Dumont, and Reinecke soils; soils that are plants. similar to the Crater Lake and Alcot soils but have Properly designed road drainage systems that include bedrock at a depth of 40 to 60 inches; and poorly drained carefully located culverts help to control erosion. Road cuts soils near drainageways and on concave slopes. Also can expose a large amount of fractured bedrock, which included are small areas of Crater Lake and Alcot soils limits the response to seeding and mulching. Steep yarding that have slopes of more than 12 percent. Included areas paths and firebreaks are subject to rilling and gullying make up about 10 percent of the total acreage. unless they are protected by a plant cover or adequate The Crater Lake soil is very deep and well drained. It water bars, or both. formed in volcanic ash and pumice. Typically, the surface is Building logging roads at midslope requires extensive covered with a layer of needles and twigs about 3.inches cutting and filling and removes land from production. thick. The surface layer is dark yellowish brown sandy loam Material that is discarded when the roads are built can about 5 inches thick. The subsoil also is dark yellowish damage vegetation and is a potential source of brown sandy loam. It is about 17 inches thick. The sedimentation. If the material becomes saturated, substratum to a depth of 60 inches is strong brown and avalanches of debris can occur. End hauling of the waste brown sandy loam. The depth to bedrock is 60 inches or material minimizes damage to the vegetation downslope more. and reduces the risk of sedimentation. Skid trails and Permeability is moderately rapid in the Crater Lake unsurfaced roads may be impassable during rainy periods. soil. Available water capacity is about 12 inches. The Logging roads require suitable surfacing for year-round use. effective rooting depth is 60 inches or more. Runoff is A high temperature in the surface layer during summer slow, and the hazard of water erosion is slight. and the low available water capacity increase the seedling The Alcot soil is very deep and somewhat excessively mortality rate. The large number of rock fragments in the drained. It formed in volcanic ash and pumice. Typically, the soil also increases the seedling mortality rate. To surface is covered with a layer of needles and twigs about 2 compensate for the expected high mortality rate, the larger inches thick. The surface layer is brown gravelly sandy loam seedlings or a greater number of seedlings should be about 4 inches thick. The subsoil also is brown gravelly planted. When the timber is harvested, leaving some of the sandy loam. It is about 7 inches thick. The substratum to a larger trees unharvested provides shade for seedlings. The depth of 60 inches is dark yellowish brown and dark grayish seedling mortality rate also can be reduced by providing brown very cobbly sandy loam. The depth to bedrock is 60 artificial shade for seedlings. Reforestation can be inches or more. accomplished by planting Douglas fir and ponderosa pine Permeability is rapid in the Alcot soil. Available water seedlings. capacity is about 9 inches. The effective rooting depth is 60 Undesirable plants limit natural or artificial inches or more. Runoff is slow, and the hazard of water reforestation unless intensive site preparation and erosion is slight. maintenance measures are applied. Mulching around This unit is used mainly for timber production, livestock seedlings helps to maintain the moisture supply in grazing, or wildlife habitat. It also is used for homesite summer and minimizes competition from undesirable development. understory plants. This unit is suited to the production of Douglas fir. Other Because of the slope and the Rock outcrop, areas of species that grow on this unit include white fir, western this unit can hinder livestock movement. hemlock, and golden chinkapin. The understory vegetation The vegetative site is Mixed Fir-Mixed Pine Forest. includes vine maple, California hazel, and cascade Oregongrape. 38C-Crater Lake -Alcot complex, 1 to 12 percent On the basis of a 100-year site curve, the mean site slopes. This map unit is on plateaus. Elevation is 2,000 to index for Douglas fir is 145 on both the Crater Lake and 3,200 feet. The mean annual precipitation is 40 to 50 Alcot soils. The yield at culmination of the mean annual inches, the mean annual temperature is 45 to 50 degrees F, increment is 9,120 cubic feet per acre in a fully stocked, and the average frost-free period is 100 to 150 days. The even-aged stand of trees at 60 years and 74,360 board feet native vegetation is mainly conifers and an understory of per acre (Scribner rule) at 110 years. On the basis of a grasses, shrubs, and forbs. 50-year curve, the mean site index is 110. This unit is about 55 percent Crater Lake soil and 35 The main limitations affecting timber production are percent Alcot soil. The components of this unit occur as compaction, erosion, plant competition, and seedling areas so intricately intermingled that mapping them mortality. Conventional methods of harvesting timber separately was not practical at the scale used. generally are suitable, but the soils may be compacted Included in this unit are small areas of Barhiskey, if they are moist when heavy equipment is used. Because of Thinning, logging, and fire reduce the density of the the high content of volcanic ash, displacement of the overstory canopy and increase the production of surface layer occurs most readily when the soils are dry. understory vegetation. Areas that support a large amount Puddling can occur when the soils are wet. Using of competing vegetation can be improved by prescribed low-pressure ground equipment causes less damage to the burning or by chemical or mechanical treatment. Seeding soils and helps to maintain productivity. Compaction can be disturbed areas to suitable plants increases forage minimized by using suitable methods of harvesting, laying production and reduces the risk of erosion. The seedling out skid trails in advance, and harvesting timber when the survival rate may be reduced if this unit is grazed when soils are least susceptible to compaction. Ripping skid trails the soils are susceptible to displacement. and landings when the soils are dry can improve the growth This unit is suited to homesite development. The main of plants. limitations are the rapid permeability in the Alcot soil and Logging roads require suitable surfacing for year-round the high content of volcanic ash and pumice in both soils. use. Construction and maintenance of roads may be This material has a moderate potential for frost action. difficult because of the volcanic ash, which is poor In some areas excavation for houses and access roads subgrade material because it is not easily compacted when exposes material that is highly susceptible to soil blowing. dry, has a moderate potential for frost action, and has a Revegetating as soon as possible in disturbed areas high water-holding capacity. When wet or moist, unsurfaced around construction sites helps to control soil blowing. roads and skid trails are soft. They may be impassable Removal of large pieces of pumice in disturbed areas is during rainy periods. When dry, they are very dusty. needed for the best results in landscaping, particularly in Erosion can be controlled by carefully planning the areas used for lawns. Because of a low amount of rainfall in construction and maintenance of logging roads, skid trails, summer, irrigation is needed in areas that support lawn and landings. Seeding, mulching, and benching areas that grasses, shrubs, vines, shade trees, or ornamental trees. have been cut and filled also help to control erosion. The vegetative site is Mixed Fir-Western Hemlock Undesirable plants limit natural or artificial reforestation Forest. unless intensive site preparation and maintenance measures are applied. Reforestation can be accomplished 39E-Crater Lake -Alcot complex, 12 to 35 percent by planting Douglas fir and ponderosa pine seedlings. north slopes. This map unit is on hillslopes. Elevation is Mulching around seedlings helps to maintain the moisture 2,000 to 3,200 feet. The mean annual precipitation is 40 to supply in summer and minimizes competition from 50 inches, the mean annual temperature is 45 to 50 undesirable understory plants. degrees F, and the average frost-free period is 100 to 150 Severe frost can damage or kill seedlings. Air days. The native vegetation is mainly conifers and an drainage may be restricted on this unit. Proper timber understory of grasses, shrubs, and forbs. harvesting methods can reduce the effect of frost on This unit is about 50 percent Crater Lake soil and 30 regeneration. percent Alcot soil. The components of this unit occur as The main limitations affecting livestock grazing are areas so intricately intermingled that mapping them compaction and soil displacement. The native vegetation separately was not practical at the scale used. suitable for grazing includes western fescue, mountain Included in this unit are small areas of Coyata, Dumont, brome, and Alaska oniongrass. If the understory is and Reinecke soils; Rock outcrop on convex slopes; soils overgrazed, the proportion of preferred forage plants that are similar to the Crater Lake and Alcot soils but have decreases and the proportion of less preferred forage bedrock at a depth of 40 to 60 inches; and poorly drained plants increases. soils near drainageways and on concave slopes. Also A planned grazing system that includes timely deferment included are small areas of Crater Lake and Alcot soils that of grazing, rotation grazing, and proper livestock distribution have slopes of less than 12 or more than 35 percent. helps to prevent overgrazing of the understory and damage Included areas make up about 20 percent of the total to the soils. Grazing should be delayed until the more acreage. . desirable forage plants have achieved enough growth to The Crater Lake soil is very deep and well drained. It withstand grazing pressure and the soils are firm enough to formed in volcanic ash and pumice. Typically, the surface is withstand trampling by livestock. Displacement of the covered with a layer of needles and twigs about 3 inches surface layer occurs most readily when the soils are dry. thick. The surface layer is dark yellowish brown sandy loam about 5 inches thick. The subsoil also is landings when the soils are dry can improve the growth of dark yellowish brown sandy loam. It is about 17 inches plants. thick. The substratum to a depth of 60 inches is strong Logging roads require suitable surfacing for year-round brown and brown sandy loam. The depth to bedrock is 60 use. Construction and maintenance of roads may be difficult inches or more. because of the volcanic ash, which is poor subgrade Permeability is moderately rapid in the Crater Lake material because it is not easily compacted when dry, has a soil. Available water capacity is about 12 inches. The moderate potential for frost action, and has a high effective rooting depth is 60. inches or more. Runoff is water-holding capacity. When wet or moist, unsurfaced medium, and the hazard of water erosion is moderate or roads and skid trails are soft. They may be impassable high. during rainy periods. When dry, they are very dusty. The Alcot soil is very deep and somewhat excessively Properly designed road drainage systems that include drained. It formed in volcanic ash and pumice. Typically, the carefully located culverts help to control erosion. Areas that surface is covered with a layer of needles and twigs about 2 have been cut and filled are easily eroded unless they are inches thick. The surface layer is brown gravelly sandy loam treated. Seeding, mulching, and benching these areas help about 4 inches thick. The subsoil also is brown gravelly to control erosion. Steep yarding paths, skid trails, and sandy loam. It is about 7 inches thick. The substratum to a firebreaks are subject to rilling and gullying unless they are depth of 60 inches is dark yellowish brown and dark grayish protected by a plant cover or adequate water bars, or both. brown very cobbly sandy loam. The depth to bedrock is 60 Undesirable plants limit natural or artificial reforestation inches or more. unless intensive site preparation and maintenance Permeability is rapid in the Alcot soil. Available water measures are applied. Reforestation can be accomplished capacity is about 9 inches. The effective rooting depth is 60 by planting Douglas fir and ponderosa pine seedlings. inches or more. Runoff is medium, and the hazard of water Mulching around seedlings helps to maintain the moisture erosion is moderate or high. supply in summer and minimizes competition from This unit is used for timber production, livestock undesirable understory plants. grazing, and wildlife habitat. The main limitations affecting livestock grazing are This unit is suited to the production of Douglas fir. Other compaction, erosion, and soil displacement. The native species that grow on this unit include white fir, western vegetation suitable for grazing includes western fescue, hemlock, and golden chinkapin. The understory vegetation mountain brome, and Alaska oniongrass. If the understory includes vine maple, California hazel, and cascade is overgrazed, the proportion of preferred forage plants Oregongrape. decreases and the proportion of less preferred forage On the basis of a 100-year site curve, the mean site plants increases. index for Douglas fir is 145 on both the Crater Lake and A planned grazing system that includes timely deferment Alcot soils. The yield at culmination of the mean annual of grazing, rotation grazing, and proper livestock distribution increment is 9,120 cubic feet per acre in a fully stocked, helps to prevent overgrazing of the understory and damage even-aged stand of trees at 60 years and 74,360 board feet to the soils. Grazing should be delayed until the more per acre (Scribner rule) at 110 years. On the basis of a desirable forage plants have achieved enough growth to 50-year curve, the mean site index is 110. withstand grazing pressure and the soils are firm enough to The main limitations affecting timber production are withstand trampling by livestock. Displacement of the erosion, compaction, and plant competition. Wheeled and surface layer occurs most readily when the soils are dry. tracked logging equipment can be used in the less sloping Thinning, logging, and fire reduce the density of the areas, but cable yarding generally is safer in the more overstory canopy and increase the production of sloping areas and results in less surface disturbance. Using understory vegetation. Areas that support a large amount standard wheeled and tracked equipment when the soils are of competing vegetation can be improved by prescribed moist causes rutting and compaction. Because of the high burning or by chemical or mechanical treatment. Seeding content of volcanic ash, displacement of the surface layer disturbed areas to suitable plants increases forage occurs most readily when the soils are dry. Puddling can production and reduces the risk of erosion. The seedling occur when the soils are wet. Using low-pressure ground survival rate may be reduced if this unit is grazed when equipment causes less damage to the soils and helps to the soils are susceptible to displacement. maintain productivity. Compaction can be minimized by The vegetative site is Mixed Fir-Western Hemlock using suitable methods of harvesting, laying out skid trails in Forest. advance, and harvesting timber when the soils are least susceptible to compaction. Ripping skid trails and 40E-Crater Lake -Alcot complex, 12 to 35 percent understory vegetation includes Pacific serviceberry, tall south slopes. This map unit is on hillslopes. Elevation is Oregongrape, and western fescue. 2,000 to 3,200 feet. The mean annual precipitation is 40 to On the basis of a 100-year site curve, the mean site 50 inches, the mean annual temperature is 45 to 50 index for Douglas fir is 135 on both the Crater Lake and degrees F, and the average frost-free period is 100 to 150 Alcot soils. The yield at culmination of the mean annual days. The native vegetation is mainly conifers and an increment is 8,280 cubic feet per acre in a fully stocked, understory of grasses, shrubs, and forbs. even-aged stand of trees at 60 years and 63,910 board feet This unit is about 50 percent Crater Lake soil and 30 per acre (Scribner rule) at 110 years. On the basis of a percent Alcot soil. The components of this unit occur as 50-year curve, the mean site index is 100. areas so intricately intermingled that mapping them The main limitations affecting timber production are separately was not practical at the scale used. erosion, compaction, plant competition, and seedling Included in this unit are small areas of Coyata, Dumont, mortality. Wheeled and tracked logging equipment can be and Reinecke soils; Rock outcrop on convex slopes; soils used in the less sloping areas, but cable yarding generally that are similar to the Crater Lake and Alcot soils but have is safer in the more sloping areas and results in less surface bedrock at a depth of 40 to 60 inches; and poorly drained disturbance. Using standard wheeled and tracked soils near drainageways and on concave slopes. Also equipment when the soils are moist causes rutting and included are small areas of Crater Lake and Alcot soils that compaction. Because of the high content of volcanic ash, have slopes of less than 12 or more than 35 percent. displacement of the surface layer occurs most readily when Included areas make up about 20 percent of the total the soils are dry. Puddling can occur when the soils are wet. acreage. Using low-pressure ground equipment causes less damage The Crater Lake soil is very deep and well drained. It to the soils and helps to maintain productivity. Compaction formed in volcanic ash and pumice. Typically, the surface is can be minimized by using suitable methods of harvesting, covered with a layer of needles and twigs about 3 inches laying out skid trails in advance, and harvesting timber thick. The surface layer is dark yellowish brown sandy loam when the soils are least susceptible to compaction. Ripping about 5 inches thick. The subsoil also is dark yellowish skid trails and landings when the soils are dry can improve brown sandy loam. It is about 17 inches thick. The the growth of plants. substratum to a depth of 60 inches is strong brown and Logging roads require suitable surfacing for year-round brown sandy loam. The depth to bedrock is 60 inches or use. Construction and maintenance of roads may be more. difficult because of the volcanic ash, which is poor Permeability is moderately rapid in the Crater Lake subgrade material because it is not easily compacted when soil. Available water capacity is about 12 inches. The dry, has a moderate potential for frost action, and has a effective rooting depth is 60 inches or more. Runoff is high water-holding capacity. When wet or moist, unsurfaced medium, and the hazard of water erosion is moderate or roads and skid trails are soft. They may be impassable high. during rainy periods. When dry, they are very dusty. The Alcot soil is very deep and somewhat excessively Properly designed road drainage systems that include drained. It formed in volcanic ash and pumice. Typically, the carefully located culverts help to control erosion. Areas that surface is covered with a layer of needles and twigs about 2 have been cut and filled are easily eroded unless they are inches thick. The surface layer is brown gravelly sandy loam treated. Seeding, mulching, and benching these areas help about 4 inches thick. The subsoil also is brown gravelly to control erosion. Steep yarding paths, skid trails, and sandy loam. It is about 7 inches thick. The substratum to a firebreaks are subject to rilling and gullying unless they are depth of 60 inches is dark yellowish brown and dark grayish protected by a plant cover or adequate water bars, or both. brown very cobbly sandy loam. The depth to bedrock is 60 Undesirable plants limit natural or artificial reforestation inches or more. unless intensive site preparation and maintenance Permeability is rapid in the Alcot soil. Available water measures are applied. Reforestation can be accomplished capacity is about 9 inches. The effective rooting depth is 60 by planting Douglas fir and ponderosa pine seedlings. inches or more. Runoff is medium, and the hazard of water Mulching around seedlings helps to maintain the moisture erosion is moderate or high. supply in summer and minimizes competition from This unit is used for timber production, livestock undesirable understory plants. grazing, and wildlife habitat. A high temperature in the surface layer and an This unit is suited to the production of Douglas fir. insufficient moisture supply in summer increase the Other species that grow on this unit include white fir, incense cedar, sugar pine, and Pacific madrone. The seedling mortality rate. To compensate for the expected brown sandy loam about 5 inches thick. The subsoil also is high mortality rate, the larger seedlings or a greater number dark yellowish brown sandy loam. It is about 17 inches of seedlings should be planted. When the timber is thick. The substratum to a depth of 60 inches is strong harvested, leaving some of the larger trees unharvested brown and brown sandy loam. The depth to bedrock is 60 provides shade for seedlings. inches or more. The main limitations affecting livestock grazing are Permeability is moderately rapid in the Crater Lake compaction, erosion, and soil displacement. The native soil. Available water capacity is about 12 inches. The vegetation suitable for grazing includes western fescue, tall effective rooting depth is 60 inches or more. Runoff is trisetum, and Alaska oniongrass. If the understory is rapid, and the hazard of water erosion is high. overgrazed, the proportion of preferred forage plants Rock outcrop consists of areas of exposed bedrock. decreases and the proportion of less preferred forage Runoff is very rapid in these areas. plants increases. This unit is used for timber production, livestock A planned grazing system that includes timely deferment grazing, and wildlife habitat. of grazing, rotation grazing, and proper livestock distribution This unit is suited to the production of Douglas fir. Other helps to prevent overgrazing of the understory and damage species that grow on this unit include white fir, western to the soils. Grazing should be delayed until the more hemlock, and golden chinkapin. The understory vegetation desirable forage plants have achieved enough growth to includes vine maple, California hazel, and cascade withstand grazing pressure and the soils are firm enough to Oregongrape. withstand trampling by livestock. Displacement of the On the basis of a 100-year site curve, the mean site surface layer occurs most readily when the soils are dry. index for Douglas fir is 145 on the Crater Lake soil. The Thinning, logging, and fire reduce the density of the yield at culmination of the mean annual increment is 9,120 overstory canopy and increase the production of cubic feet per acre in a fully stocked, even-aged stand of understory vegetation. Areas that support a large amount trees at 60 years and 74,360 board feet per acre (Scribner of competing vegetation can be improved by prescribed rule) at 110 years. On the basis of a 50-year curve, the burning or by chemical or mechanical treatment. Seeding mean site index is 110. disturbed areas to suitable plants increases forage The main limitations affecting timber production are the production and reduces the risk of erosion. The seedling slope, the Rock outcrop, erosion, compaction, and plant survival rate may be reduced if this unit is grazed when competition. Wheeled and tracked logging equipment can the soils are too dry. be used in the less sloping areas, but cable yarding The vegetative site is Mixed Fir-Mixed Pine Forest. generally is safer and results in less surface disturbance. Using standard wheeled and tracked equipment when the 41G-Crater Lake -Rock outcrop complex, 35 to 70 soil is moist causes rutting and compaction. Because of the percent north slopes. This map unit is on hillslopes. high content of volcanic ash, displacement of the surface Elevation is 2,000 to 3,200 feet. The mean annual layer occurs most readily when the soil is dry. Puddling can precipitation is 40 to 50 inches, the mean annual occur when the soil is wet. Using low-pressure ground temperature is 45 to 50 degrees F, and the average equipment causes less damage to the soil and helps to frost-free period is 100 to 150 days. The native vegetation maintain productivity. Compaction can be minimized by is mainly conifers and an understory of grasses, shrubs, using suitable methods of harvesting, laying out skid trails in and forbs. advance, and harvesting timber when the soil is least This unit is about 55 percent Crater Lake soil and 20 susceptible to compaction. Ripping skid trails and landings percent Rock outcrop. The components of this unit occur when the soil is dry can improve the growth of plants. as areas so intricately intermingled that mapping them Logging roads require suitable surfacing for year-round separately was not practical at the scale used. use. Construction and maintenance of roads may be difficult Included in this unit are small areas of Alcot, Coyata, because of the volcanic ash, which is poor subgrade Dumont, and Reinecke soils; soils that are similar to the material because it is not easily compacted when dry, has a Crater Lake soil but have bedrock within a depth of 60 moderate potential for frost action, and has a high inches; and Crater Lake soils that have slopes of less than water-holding capacity. When wet or moist, unsurfaced 35 or more than 70 percent. Included areas make up about roads and skid trails are soft. They may be impassable 25 percent of the total acreage. during rainy periods. When dry, they are very dusty. The Crater Lake soil is very deep and well drained. It Properly designed road drainage systems that include formed in volcanic ash and pumice. Typically, the surface is carefully located culverts help to control erosion. covered with a layer of needles and twigs about 3 inches thick. The surface layer is dark yellowish Areas that have been cut and filled are easily eroded 42G-Crater Lake -Rock outcrop complex, 35 to 70 unless they are treated. Seeding, mulching, and benching percent south slopes. This map unit is on hillslopes. these areas help to control erosion. Steep yarding paths, Elevation is 2,000 to 3,200 feet. The mean annual skid trails, and firebreaks are subject to rilling and gullying precipitation is 40 to 50 inches, the mean annual unless they are protected by a plant cover or adequate temperature is 45 to 50 degrees F, and the average water bars, or both. Cutbanks occasionally slump when frost-free period is 100 to 150 days. The native vegetation the soil is saturated. is mainly conifers and an understory of grasses, shrubs, Constructing logging roads on the steeper slopes can and forbs. result in a high risk of erosion. Building the roads at This unit is about 55 percent Crater Lake soil and 20 midslope requires extensive cutting and filling and removes percent Rock outcrop. The components of this unit occur as land from production. Material that is discarded when the areas so intricately intermingled that mapping them roads are built can damage vegetation and is a potential separately was not practical at the scale used. source of sedimentation. If the material becomes saturated, Included in this unit are small areas of Alcot, Coyata, avalanches of debris can occur. End hauling of the waste Dumont, and Reinecke soils; soils that are similar to the material minimizes damage to the vegetation downslope Crater Lake soil but have bedrock within a depth of 60 and reduces the risk of sedimentation. inches; and Crater Lake soils that have slopes of less than Undesirable plants limit natural or artificial reforestation 35 or more than 70 percent. Included areas make up about unless intensive site preparation and maintenance 25 percent of the total acreage. measures are applied. Reforestation can be accomplished The Crater Lake soil is very deep and well drained. It by planting Douglas fir and ponderosa pine seedlings. formed in volcanic ash and pumice. Typically, the surface is Mulching around seedlings helps to maintain the moisture covered with a layer of needles and twigs about 3 inches supply in summer and minimizes competition from thick. The surface layer is dark yellowish brown sandy loam undesirable understory plants. about 5 inches thick. The subsoil also is dark yellowish The main limitations affecting livestock grazing are brown sandy loam. It is about 17 inches thick. The erosion, compaction, soil displacement, the slope, and the substratum to a depth of 60 inches is strong brown and Rock outcrop. The native vegetation suitable for grazing brown sandy loam. The depth to bedrock is 60 inches or includes western fescue, mountain brome, and Alaska more. oniongrass. If the understory is overgrazed, the proportion Permeability is moderately rapid in the Crater Lake of preferred forage plants decreases and the proportion of soil. Available water capacity is about 12 inches. The less preferred forage plants increases. effective rooting depth is 60 inches or more. Runoff is A planned grazing system that includes timely deferment rapid, and the hazard of water erosion is high. of grazing, rotation grazing, and proper livestock distribution Rock outcrop consists of areas of exposed bedrock. helps to prevent overgrazing of the understory and damage Runoff is very rapid in these areas. to the soil. Grazing should be delayed until the more This unit is used for timber production, livestock desirable forage plants have achieved enough growth to grazing, and wildlife habitat. withstand grazing pressure and the soil is firm enough to This unit is suited to the production of Douglas fir. Other withstand trampling by livestock. Displacement of the species that grow on this unit include white fir, incense surface layer occurs most readily when the soil is dry. cedar, sugar pine, and Pacific madrone. The understory Because of the slope and the Rock outcrop, areas of this vegetation includes Pacific serviceberry, tall Oregongrape, unit can hinder livestock movement. and western fescue. Thinning, logging, and fire reduce the density of the On the basis of a 100-year site curve, the mean site overstory canopy and increase the production of index for Douglas fir is 135 on the Crater Lake soil. The understory vegetation. Areas that support a large amount yield at culmination of the mean annual increment is 8,280 of competing vegetation can be improved by prescribed cubic feet per acre in a fully stocked, even-aged stand of burning or by chemical or mechanical treatment. Seeding trees at 60 years and 63,910 board feet per acre (Scribner disturbed areas to suitable plants increases forage rule) at 110 years. On the basis of a 50-year curve, the production and reduces the risk of erosion. The seedling mean site index is 100. survival rate may be reduced if this unit is grazed when The main limitations affecting timber production are the the soil is too dry. slope, the Rock outcrop, erosion, compaction, seedling The vegetative site is Mixed Fir-Western Hemlock mortality, and plant competition. Wheeled and tracked Forest. logging equipment can be used in the less sloping areas, but cable yarding generally is safer and results in less surface disturbance. Using standard wheeled and tracked equipment when the soil is moist causes rutting and compaction. Because of the high summer and minimizes competition from undesirable content of volcanic ash, displacement of the surface layer understory plants. occurs most readily when the soil is dry. Puddling can occur The main limitations affecting livestock grazing are when the soil is wet. Using low-pressure ground equipment erosion, compaction, soil displacement, the slope, and the causes less damage to the soil and helps to maintain Rock outcrop. The native vegetation suitable for grazing productivity. Compaction can be minimized by using includes western fescue, tall trisetum, and Alaska suitable methods of harvesting, laying out skid trails in oniongrass. If the understory is overgrazed, the proportion advance, and harvesting timber when the soil is least of preferred forage plants decreases and the proportion of susceptible to compaction . Ripping skid trails and landings less preferred forage plants increases. when the soil is dry can improve the growth of plants. A planned grazing system that includes timely deferment Logging roads require suitable surfacing for year-round of grazing, rotation grazing, and proper livestock distribution use. Construction and maintenance of roads may be helps to prevent overgrazing of the understory and damage difficult because of the volcanic ash, which is poor to the soil. Grazing should be delayed until the more subgrade material because it is not easily compacted when desirable forage plants have achieved enough growth to dry, has a moderate potential for frost action, and has a withstand grazing pressure and the soil is firm enough to high water-holding capacity. When wet or moist, unsurfaced withstand trampling by livestock. Displacement of the roads and skid trails are soft. They may be impassable surface layer occurs most readily when the soil is dry. during rainy periods. When dry, they are very dusty. Because of the slope and the Rock outcrop, areas of this Properly designed road drainage systems that include unit can hinder livestock movement. carefully located culverts help to control erosion. Areas that Thinning, logging, and fire reduce the density of the have been cut and filled are easily eroded unless they are overstory canopy and increase the production of treated. Seeding, mulching, and benching these areas help understory vegetation. Areas that support a large amount to control erosion. Steep yarding paths, skid trails, and of competing vegetation can be improved by prescribed firebreaks are subject to rilling and gullying unless they are burning or by chemical or mechanical treatment. Seeding protected by a plant cover or adequate water bars, or both. disturbed areas to suitable plants increases forage Cutbanks occasionally slump when the soil is saturated. production and reduces the risk of erosion. The seedling Constructing logging roads on the steeper slopes can survival rate may be reduced if this unit is grazed when result in a high risk of erosion. Building the roads at the soil is too dry. midslope requires extensive cutting and filling and removes The vegetative site is Mixed Fir-Mixed Pine Forest. land from production. Material that is discarded when the roads are built can damage vegetation and is a potential 43B-Darow silty clay loam, 1 to 5 percent slopes. source of sedimentation. If the material becomes saturated, This moderately deep, moderately well drained soil is on avalanches of debris can occur. End hauling of the waste hillslopes. It formed in residuum derived dominantly from material minimizes damage to the vegetation downslope siltstone. Elevation is 1,200 to 3,000 feet. The mean annual and reduces the risk of sedimentation. precipitation is 18 to 30 inches, the mean annual A high temperature in the surface layer and an temperature is 52 to 54 degrees F, and the average insufficient moisture supply in summer increase the frost-free period is 120 to 180 days. The native vegetation is seedling mortality rate. To compensate for the expected mainly hardwoods and an understory of grasses, shrubs, high mortality rate, the larger seedlings or a greater number and forbs. of seedlings should be planted. When the timber is Typically, the surface layer is dark brown silty clay harvested, leaving some of the larger trees unharvested loam about 12 inches thick. The subsoil is dark brown and provides shade for seedlings. The seedling mortality rate dark yellowish brown silty clay about 20 inches thick. also can be reduced by providing artificial shade for Weathered bedrock is at a depth of about 32 inches. The seedlings. Reforestation can be accomplished by planting depth to bedrock ranges from 20 to 40 inches. Douglas fir and ponderosa pine seedlings. Included in this unit are small areas of Brader and Undesirable plants limit natural or artificial Debenger soils on ridges and convex slopes; Carney, reforestation unless intensive site preparation and Coker, and Selmac soils on concave slopes; Cove, maintenance measures are applied. Mulching around Gregory, and Padigan soils near drainageways; Manita seedlings helps to maintain the moisture supply in soils; and soils that are similar to the Darow soil but have bedrock at a depth of more than 40 inches. Also included are small areas of Darow soils that have slopes of more than 5 percent. Included areas make up included soils are throughout the unit. Onsite about 20 percent of the total acreage. investigation is needed to locate such soils. Permeability is slow in the Darow soil. Available water If buildings are constructed on this unit, properly capacity is about 5 inches. The effective rooting depth is 20 designing foundations and footings, diverting runoff away to 40 inches. Runoff is slow, and the hazard of water from the buildings, and backfilling with material that has a erosion is slight. The water table fluctuates between depths low shrink -swell potential help to prevent the structural of 3.0 and 3.5 feet from December through April. damage caused by shrinking and swelling. Properly This unit is used mainly for hay and pasture or for tree designing buildings and roads helps to offset the limited fruit. It also is used for homesite development and ability of the soil to support a load. livestock grazing. Revegetating as soon as possible helps to control This unit is suited to irrigated crops. It is limited mainly by erosion in disturbed areas around construction sites. the high content of clay, a slow rate of water intake, and Topsoil can be stockpiled and used to reclaim areas droughtiness. In summer, irrigation is needed for the disturbed during construction. In many areas it may be maximum production of most crops. Sprinkler and trickle necessary to haul in topsoil for lawns and gardens. irrigation systems are suitable. These systems permit an Because of a low amount of rainfall in summer, irrigation is even, controlled application of water, help to prevent needed in areas that support lawn grasses, shrubs, vines, excessive runoff, and minimize the risk of erosion. Border shade trees, or ornamental trees. and contour flood irrigation systems also are suitable. For The main limitations affecting livestock grazing are the efficient application and removal of surface irrigation compaction, the clayey surface layer, and droughtiness. water, land leveling is needed. Because of the slow The vegetation suitable for grazing includes Idaho fescue, permeability, water applications should be regulated so that California brome, and prairie junegrass. If the range is the water does not stand on the surface and damage the overgrazed, the proportion of preferred forage plants crop. Land smoothing and open ditches can reduce surface decreases and the proportion of less preferred forage wetness. The use of pipe, ditch lining, or drop structures in plants increases. Grazing should be delayed until the more irrigation ditches reduces water loss and the hazard of desirable forage plants have achieved enough growth to erosion. withstand grazing pressure and the soil is firm enough to Solid-set sprinkler irrigation is the best method of withstand trampling by livestock. controlling frost and providing adequate moisture for tree Suitable management practices on this unit include fruit. Compaction can be minimized by limiting the use of proper grazing use, deferred grazing, rotation grazing, and equipment when the soil is wet. A permanent cover crop brush control. Areas that support a large amount of helps to control runoff and erosion. competing vegetation can be improved by chemical or This unit is well suited to permanent pasture. The high mechanical treatment. content of clay limits tillage and root growth. Deep cracks Range seeding is suitable if the site is in poor condition. form as the soil dries in summer. Proper stocking rates, The main limitations are the clayey surface layer and pasture rotation, and restricted grazing during wet periods droughtiness. The plants selected for seeding should be help to keep pastures in good condition and protect the soil those that meet the seasonal requirements of livestock or from erosion. Grazing when the soil is wet results in wildlife, or both. compaction of the surface layer, poor tilth, and excessive This unit is limited as a site for livestock watering runoff. Periodic mowing and clipping help to maintain ponds and other water impoundments because of the uniform plant growth, discourage selective grazing, and depth to bedrock. reduce the extent of clumpy growth. Fertilizer is needed to The vegetative site is Droughty North, 18- to 35-inch ensure the optimum growth of grasses and legumes. precipitation zone. Grasses respond to nitrogen, and legumes respond to sulfur and phosphorus. 43D-Darow silty clay loam, 5 to 20 percent slopes. The main limitations affecting homesite development This moderately deep, moderately well drained soil is on are the slow permeability, a high shrink -swell potential, the hillslopes. It formed in colluvium and residuum derived depth to bedrock, and low strength. dominantly from siltstone. Elevation is 1,200 to 3,000 feet. This unit is poorly suited to standard systems of The mean annual precipitation is 18 to 30 inches, the mean waste disposal because of the slow permeability and the annual temperature is 52 to 54 degrees F, and the average depth to bedrock. Alternative waste disposal systems frost-free period is 120 to 180 days. The native vegetation is may function properly on this unit. Suitable mainly hardwoods and an understory of grasses, shrubs, and forbs. Typically, the surface layer is dark brown silty clay loam about 12 inches thick. The subsoil is dark brown and dark yellowish brown silty clay about 20 inches The main limitations affecting homesite development thick. Weathered bedrock is at a depth of about 32 are the slow permeability, a high shrink -swell potential, the inches. The depth to bedrock ranges from 20 to 40 slope, the depth to bedrock, and low strength. inches. This unit is poorly suited to standard systems of waste Included in this unit are small areas of Brader and disposal because the slow permeability and the depth to Debenger soils on ridges and convex slopes; Carney, bedrock. Alternative waste disposal systems may function Coker, and Selmac soils on concave slopes; Cove, properly on this unit. Suitable included soils are Gregory, and Padigan soils near drainageways; Manita throughout the unit. Onsite investigation is needed to soils; and soils that are similar to the Darow soil but have locate such soils. bedrock at a depth of more than 40 inches. Also included If buildings are constructed on this unit, properly are small areas of Darow soils that have slopes of less than designing foundations and footings, diverting runoff away 5 or more than 20 percent. Included areas make up about from the buildings, and backfilling with material that has a 20 percent of the total acreage. low shrink -swell potential help to prevent the structural Permeability is slow in the Darow soil. Available water damage caused by shrinking and swelling. Properly capacity is about 5 inches. The effective rooting depth is 20 designing buildings and roads helps to offset the limited to 40 inches. Runoff is slow or medium, and the hazard of ability of the soil to support a load. water erosion is slight or moderate. The water table Erosion is a hazard on the steeper slopes. Only the part fluctuates between depths of 3.0 and 3.5 feet from of the site that is used for construction should be disturbed. December through April. Revegetating as soon as possible helps to control erosion This unit is used mainly for hay and pasture or for tree in disturbed areas around construction sites. Topsoil can fruit. It also is used for homesite development .and be stockpiled and used to reclaim areas disturbed during livestock grazing. construction. In many areas it may be necessary to haul in This unit is suited to irrigated crops. It is limited mainly by topsoil for lawns and gardens. Because of a low amount of the high content of clay, a slow rate of water intake, and rainfall in summer, irrigation is needed in areas that droughtiness. In summer, irrigation is needed for the support lawn grasses, shrubs, vines, shade trees, or maximum production of most crops. Because of the slope, ornamental trees. sprinkler and trickle irrigation systems are the best methods The main limitations affecting livestock grazing are of applying water. These systems permit an even, compaction, erosion, the clayey surface layer, and controlled application of water, help to prevent excessive droughtiness. The vegetation suitable for grazing includes runoff, and minimize the risk of erosion. To prevent Idaho fescue, California brome, and prairie junegrass. If the overirrigation and excessive erosion, applications of range is overgrazed, the proportion of preferred forage irrigation water should be adjusted to the available water plants decreases and the proportion of less preferred capacity, the rate of water intake, and the needs of the forage plants increases. Grazing should be delayed until crop. the more desirable forage plants have achieved enough Solid-set sprinkler irrigation is the best method of growth to withstand grazing pressure and the soil is firm controlling frost and providing adequate moisture for tree enough to withstand trampling by livestock. fruit. Compaction can be minimized by limiting the use of Suitable management practices on this unit include equipment when the soil is wet. A permanent cover crop proper grazing use, deferred grazing, rotation grazing, and helps to control runoff and erosion. brush control. Areas that support a large amount of This unit is well suited to permanent pasture. The high competing vegetation can be improved by chemical or content of clay limits tillage and root growth. Deep cracks mechanical treatment. form as the soil dries in summer. Seedbeds should be Range seeding is suitable if the site is in poor condition. prepared on the contour or across the slope where practical. The main limitations are the clayey surface layer and Proper stocking rates, pasture rotation, and restricted droughtiness. The plants selected for seeding should be grazing during wet periods help to keep pastures in good those that meet the seasonal requirements of livestock or condition and protect the soil from erosion. Grazing when wildlife, or both. the soil is wet results in compaction of the surface layer, This unit is limited as a site for livestock watering poor tilth, and excessive runoff. Periodic mowing and ponds and other water impoundments because of the clipping help to maintain uniform plant growth, discourage slope and the depth to bedrock. selective grazing, and reduce the extent of clumpy growth. The vegetative site is Droughty North, 18- to 35-inch Fertilizer is needed to ensure the optimum growth of precipitation zone. grasses and legumes. Grasses respond to nitrogen, and legumes respond to sulfur and phosphorus. 43E-Darow silty clay loam, 20 to 35 percent slopes. disturbed. Revegetating as soon as possible helps to This moderately deep, moderately well drained soil is on control erosion in disturbed areas around construction hillslopes. It formed in colluvium derived dominantly from sites. Topsoil can be stockpiled and used to reclaim areas siltstone. Elevation is 1,200 to 3,000 feet. The mean disturbed during construction. In many areas it may be annual precipitation is 18 to 30 inches, the mean annual necessary to haul in topsoil for lawns and gardens. temperature is 52 to 54 degrees F, and the average Because of a low amount of rainfall in summer, irrigation is frost-free period is 120 to 180 days. The native vegetation needed in areas that support lawn grasses, shrubs, vines, is mainly hardwoods and an understory of grasses, shrubs, shade trees, or ornamental trees. and forbs. The main limitations affecting livestock grazing are Typically, the surface layer is dark brown silty clay compaction, erosion, the clayey surface layer, droughtiness, loam about 12 inches thick. The subsoil is dark brown and the slope. The vegetation suitable for grazing includes and dark yellowish brown silty clay about 20 inches thick. Idaho fescue, California brome, and prairie junegrass. If the Weathered bedrock is at a depth of about 32 inches. The range is overgrazed, the proportion of preferred forage depth to bedrock ranges from 20 to 40 inches. plants decreases and the proportion of less preferred forage Included in this unit are small areas of Rock outcrop and plants increases. Grazing should be delayed until the more Brader and Debenger soils on ridges and convex slopes; desirable forage plants have achieved enough growth to Carney, Coker, and Selmac soils on concave slopes; Cove, withstand grazing pressure and the soil is firm enough to Gregory, and Padigan soils near drainageways; Manita withstand trampling by livestock. soils; and soils that are similar to the Darow soil but have Suitable management practices on this unit include bedrock at a depth of more than 40 inches. Also included proper grazing 'use, deferred grazing, rotation grazing, and are small areas of Darow soils that have slopes of less than brush control. Areas that support a large amount of 20 or more than 35 percent. Included areas make up about competing vegetation can be improved by chemical or 20 percent of the total acreage. mechanical treatment. In places the use of ground Permeability is slow in the Darow soil. Available water equipment and access by livestock are limited by the slope. capacity is about 5 inches. The effective rooting depth is Range seeding is suitable if the site is in poor condition. 20 to 40 inches. Runoff is medium, and the hazard of The main limitations are the clayey surface layer, the water erosion is moderate. The water table fluctuates slope, and droughtiness. The plants selected for seeding between depths of 3.0 and 3.5 feet from December should be those that meet the seasonal requirements of through April. livestock or wildlife, or both. This unit is used mainly for homesite development or This unit is limited as a site for livestock watering livestock grazing. It also is used for tree fruit. ponds and other water impoundments because of the The main limitations affecting homesite development slope and the depth to bedrock. are the slow permeability, a high shrink -swell potential, the Solid-set sprinkler irrigation is the best method of slope, the depth to bedrock, and low strength. controlling frost and providing adequate moisture for tree This unit is poorly suited to standard systems of waste fruit. Compaction can be minimized by limiting the use of disposal because of the slow permeability, the depth to equipment when the soils are wet. A permanent cover crop bedrock, and the slope. Alternative waste disposal helps to control runoff and erosion. systems may function properly on this unit. Suitable The vegetative site is Droughty North, 18- to 35-inch included soils are throughout the unit. Onsite precipitation zone. investigation is needed to locate such soils. The slope limits the use of the steeper areas of this unit 44C-Debenger-Brader loams, 1 to 15 percent slopes. for building site development. Cuts needed to provide This map unit is on knolls and ridges. Elevation is 1,000 to essentially level building sites can expose bedrock. 3,500 feet. The mean annual precipitation is 18 to 35 Properly designing foundations and footings, diverting inches, the mean annual temperature is 50 to 54 degrees F, runoff away from the buildings, and backfilling with material and the average frost-free period is 150 to 180 days. The that has a low shrink-swell potential help to prevent the native vegetation is mainly hardwoods and an understory of structural damage caused by shrinking and swelling. grasses, shrubs, and forbs. Properly designing buildings and roads helps to offset the This unit is about 60 percent Debenger soil and 20 limited ability of the soil to support a load. percent Brader soil. The components of this unit occur as Erosion is a hazard on the steeper slopes. Only the areas so intricately intermingled that mapping them part of the site that is used for construction should be separately was not practical at the scale used. Included in this unit are small areas of Rock outcrop on grazing during wet periods help to keep pastures in good convex slopes; Carney, Coker, and Darow soils on condition and protect the soils from erosion. Grazing when concave slopes; poorly drained soils that are similar to the the soils are wet results in compaction of the surface layer, Debenger soil; Padigan soils near drainageways; poor tilth, and excessive runoff. Periodic mowing and Langellain and Ruch soils; and soils that are similar to the clipping help to maintain uniform plant growth, discourage Brader soil but have bedrock within a depth of 12 inches. selective grazing, and reduce the extent of clumpy growth. Also included are small areas of Debenger and Brader Fertilizer is needed to ensure the optimum growth of soils that have slopes of more than 15 percent. Included grasses and legumes. Grasses respond to nitrogen, and areas make up about 20 percent of the total acreage. legumes respond to sulfur and phosphorus. The Debenger soil is moderately deep and well drained. The main limitations affecting livestock grazing are It formed in colluvium derived dominantly from sandstone. compaction, erosion, droughtiness, and the depth to Typically, the surface layer is dark brown loam about 5 bedrock in the Brader soil. The vegetation suitable for inches thick. The next layer is reddish brown loam about 4 grazing includes Idaho fescue, bluebunch wheatgrass, and inches thick. The subsoil is reddish brown and yellowish red pine bluegrass. If the range is overgrazed. the proportion of clay loam about 18 inches thick. Weathered bedrock is at a preferred forage plants decreases and the proportion of less depth of about 27 inches. The depth to bedrock ranges preferred forage plants increases. Grazing should be from 20 to 40 inches. delayed until the soils are firm and the more desirable Permeability is moderate in the Debenger soil. Available forage plants have achieved enough growth to withstand water capacity is about 5 inches. The effective rooting depth grazing pressure. is 20 to 40 inches. Runoff is slow or medium, and the hazard Suitable management practices on this unit include of water erosion is slight or moderate. proper grazing use, deferred grazing, rotation grazing, and The Brader soil is shallow and well drained. It formed in brush control. Areas that support a large amount of colluvium derived dominantly from sandstone. Typically, the competing vegetation can be improved by chemical or surface layer is dark brown loam about 6 inches thick. The mechanical treatment. subsoil is dark reddish brown loam about 7 inches thick. Range seeding is suitable if the site is in poor condition. Weathered bedrock is at a depth of about 13 inches. The The main limitations are the depth to bedrock in the Brader depth to bedrock ranges from 12 to 20 inches. soil and droughtiness in both soils. The plants selected for Permeability is moderate in the Brader soil. Available seeding should be those that meet the seasonal water capacity is about 2 inches. The effective rooting depth requirements of livestock or wildlife, or both. is 12 to 20 inches. Runoff is slow or medium, and the This unit is limited as a site for livestock watering hazard of water erosion is slight or moderate. ponds and other water impoundments because of the This unit is used for hay and pasture, livestock depth to bedrock. grazing, and homesite development. The main limitation affecting homesite development is This unit is suited to irrigated hay and pasture. It is the depth to bedrock. limited mainly by the depth to bedrock in the Brader soil and This unit is poorly suited to septic tank absorption fields droughtiness in both soils. In summer, irrigation is needed because of the depth to bedrock. The absorption fields can for the maximum production of most forage crops. Sprinkler be installed in areas of the unit where the bedrock is at a irrigation is the best method of applying water. This method greater depth. Onsite investigation is needed to locate permits an even, controlled application of water, helps to such areas. prevent excessive runoff, and minimizes the risk of erosion. Cuts needed to provide essentially level building sites Border and contour flood irrigation systems also are suitable can expose bedrock. Revegetating as soon as possible in the less sloping areas. For the efficient application and helps to control erosion in disturbed areas around removal of surface irrigation water, land leveling is needed. construction sites. Topsoil can be stockpiled and used to The bedrock underlying the Brader soil, however, may be reclaim areas disturbed during construction. In many areas it exposed. To prevent overirrigation and excessive erosion, may be necessary to haul in topsoil for lawns and gardens. applications of irrigation water should be adjusted to the Because of a low amount of rainfall in summer, irrigation is available water capacity, the rate of water intake, and the needed in areas that support lawn grasses, shrubs, vines, needs of the crop. shade trees, or ornamental trees. Proper stocking rates, pasture rotation, and restricted The vegetative site in areas of the Debenger soil is Loamy Slopes, 18- to 24-inch precipitation zone, and the one in areas of the Brader soil is Loamy Hills, 20- to The main limitations affecting livestock grazing are 35-inch precipitation zone. compaction, erosion, droughtiness, the slope, and the depth to bedrock in the Brader soil. The vegetation 44E-Debenger-Brader loams, 15 to 40 percent suitable for grazing includes Idaho fescue, bluebunch slopes. This map unit is on knolls and ridges. Elevation is wheatgrass, and pine bluegrass. If the range is 1,000 to 3,500 feet. The mean annual precipitation is 18 to overgrazed, the proportion of preferred forage plants 35 inches, the mean annual temperature is 50 to 54 decreases and the proportion of less preferred forage degrees F, and the average frost-free period is 150 to 180 plants increases. Grazing should be delayed until the days. The native vegetation is mainly hardwoods and an more desirable forage plants have achieved enough understory of grasses, shrubs, and forbs. growth to withstand grazing pressure and the soils are firm This unit is about 55 percent Debenger soil and 20 enough to withstand trampling by livestock. percent Brader soil. The components of this unit occur as Suitable management practices on this unit include areas so intricately intermingled that mapping them proper grazing use, deferred grazing, rotation grazing, and separately was not practical at the scale used. brush control. Areas that support a large amount of Included in this unit are small areas of Rock outcrop on competing vegetation can be improved by chemical or convex slopes, Carney and Darow soils on concave slopes, mechanical treatment. In places the use of ground Padigan soils near drainageways, Heppsie soils on the equipment and access by livestock are limited by the slope. steeper parts of the landscape, and Langellain and Ruch Constructing trails or walkways allows livestock to graze in soils. Also included are small areas of soils that are similar areas where access is limited. to the Debenger and Brader soils but have more than 35 Range seeding is suitable if the site is in poor condition. percent rock fragments, soils that are similar to the Brader The main limitations are the depth to bedrock in the Brader soil but have bedrock within a depth of 12 inches, and soil, droughtiness, and the slope. The plants selected for Debenger and Brader soils that have slopes of less than 15 seeding should be those that meet the seasonal or more than 40 percent. Included areas make up about 25 requirements of livestock or wildlife, or both. percent of the total acreage. This unit is limited as a site for livestock watering The Debenger soil is moderately deep and well drained. ponds and other water impoundments because of the It formed in colluvium derived dominantly from sandstone. slope and the depth to bedrock. Typically, the surface layer is dark brown loam about 5 The main limitations affecting homesite development are inches thick. The next layer is reddish brown loam about 4 the depth to bedrock and the slope. The slope limits the use inches thick. The subsoil is reddish brown and yellowish red of the steeper areas of this unit for building site clay loam about 18 inches thick. Weathered bedrock is at a development. Cuts needed to provide essentially level depth of about 27 inches. The depth to bedrock ranges building sites can expose bedrock. Erosion is a hazard on from 20 to 40 inches. the steeper slopes. Only the part of the site that is used for Permeability is moderate in the Debenger soil. Available construction should be disturbed. water capacity is about 5 inches. The effective rooting depth This unit is poorly suited to septic tank absorption is 20 to 40 inches. Runoff is medium or rapid, and the fields because of the depth to bedrock and the slope. hazard of water erosion is moderate or high. The absorption fields can be installed in areas of the unit The Brader soil is shallow and well drained. It formed in where the soils are deeper over bedrock and are less colluvium derived dominantly from sandstone. Typically, the sloping. Onsite investigation is needed to locate such surface layer is dark brown loam about 6 inches thick. The areas. subsoil is dark reddish brown loam about 7 inches thick. Revegetating as soon as possible helps to control Weathered bedrock is at a depth of about 13 inches. The erosion in disturbed areas around construction sites. depth to bedrock ranges from 12 to 20 inches. Topsoil can be stockpiled and used to reclaim areas Permeability is moderate in the Brader soil. Available disturbed during construction. In many areas it may be water capacity is about 2 inches. The effective rooting necessary to haul in topsoil for lawns and gardens. depth is 12 to 20 inches. Runoff is medium or rapid, and Because of a low amount of rainfall in summer, irrigation is the hazard of water erosion is moderate or high. needed in areas that support lawn grasses, shrubs, vines, This unit is used mainly for livestock grazing or shade trees, or ornamental trees. homesite development. Some of the less sloping areas are The vegetative site in areas of the Debenger soil is used for hay and pasture. Loamy Slopes, 18- to 24-inch precipitation zone, and the one in areas of the Brader soil is Loamy Hills, 20- to 35-inch precipitation zone. 45G-Donegan gravelly loam, 35 to 65 percent north in the less sloping areas, but cable yarding generally is slopes. This moderately deep, well drained soil is on safer and results in less surface disturbance. If the soil is hillslopes. It formed in colluvium derived from andesite and excessively disturbed when timber is harvested or logging volcanic ash. Elevation is 4,000 to 5,100 feet. The mean roads are built, a larger number of rock fragments is left on annual precipitation is 40 to 50 inches, the mean annual the surface. Using standard wheeled and tracked temperature is 41 to 45 degrees F, and the average equipment when the soil is moist causes rutting and frost-free period is less than 100 days. The native compaction. Puddling can occur when the soil is wet. Using vegetation is mainly conifers and an understory of grasses, low-pressure ground equipment causes less damage to the shrubs, and forbs. soil and helps to maintain productivity. Compaction can be Typically, the surface is covered with a layer of needles, minimized by using suitable methods of harvesting, laying leaves, and twigs about 3 inches thick. The surface layer is out skid trails in advance, and harvesting timber when the dark brown gravelly loam about 10 inches thick. The next 12 soil is least susceptible to compaction. Ripping skid trails inches also is dark brown gravelly loam. The subsoil is dark and landings when the soil is dry can improve the growth of brown extremely gravelly loam about 10 inches thick. plants. Weathered bedrock is at a depth of about 32 inches. The Properly designed road drainage systems that include depth to bedrock ranges from 20 to 40 inches. In some carefully located culverts help to control erosion Seeding, areas the surface layer is stony. mulching, and benching areas that have been cut and filled Included in this unit are small areas of Killet soils on also help to control erosion. Steep yarding paths, skid trails, concave slopes, soils that are similar to Killet soils but have and firebreaks are subject to rilling and gullying unless they bedrock within a depth of 60 inches, Rock outcrop on are protected by a plant cover or adequate water bars, or convex slopes, and soils that are similar to the Donegan both. Cutbanks occasionally slump when the soil is soil but have bedrock at a depth of more than 40 inches. saturated. Also included are small areas of Donegan soils that have Constructing logging roads on the steeper slopes can slopes of less than 35 or more than 65 percent. Included result in a high risk of erosion. Building the roads at areas make up about 20 percent of the total acreage. midslope requires extensive cutting and filling and removes Permeability is moderately slow in the Donegan soil. land from production. Material that is discarded when the Available water capacity is about 4 inches. The effective roads are built can damage vegetation and is a potential rooting depth is 20 to 40 inches. Runoff is rapid, and the source of sedimentation. If the material becomes saturated, hazard of water erosion is high. avalanches of debris can occur. End hauling of the waste This unit is used for timber production, livestock material minimizes damage to the vegetation downslope grazing, and wildlife habitat. and reduces the risk of sedimentation. Skid trails and This unit is suited to the production of Douglas fir and unsurfaced roads may be impassable during rainy periods. white fir. Other species that grow on this unit include Logging roads require suitable surfacing for year-round use. incense cedar, western hemlock, and Pacific dogwood. Undesirable plants limit natural or artificial reforestation The understory vegetation includes cascade unless intensive site preparation and maintenance Oregongrape, vine maple, and deerfoot vanillaleaf. measures are applied. Reforestation can be accomplished On the basis of a 100-year site curve, the mean site by planting ponderosa pine and Douglas fir seedlings. index for Douglas fir is 140. The yield at culmination of the Mulching around seedlings helps to maintain the moisture mean annual increment is 8,700 cubic feet per acre in a supply in summer and minimizes competition from fully stocked, even-aged stand of trees at 60 years and undesirable understory plants. 69,410 board feet per acre (Scribner rule) at 110 years. On Severe frost can damage or kill seedlings. Proper timber the basis of a 50-year curve, the mean site index is 105. harvesting methods can reduce the effect of frost on On the basis of a 50-year site curve, the mean site regeneration. index for white fir is 85. The yield at culmination of the The main limitations affecting livestock grazing are mean annual increment is 14,420 cubic feet per acre in a erosion, compaction, and the slope. The native vegetation fully stocked, even-aged stand of trees at 70 years. suitable for grazing includes western fescue, mountain The main limitations affecting timber production are brome, and Alaska oniongrass. If the understory is the slope, erosion, compaction, plant competition, and overgrazed, the proportion of preferred forage plants seedling mortality. Also, the bedrock restricts root growth. decreases and the proportion of less preferred forage As a result, windthrow is a hazard. plants increases. Wheeled and tracked logging equipment can be used A planned grazing system that includes timely deferment of grazing, rotation grazing, and proper livestock The understory vegetation includes Whipplevine, Pacific distribution helps to prevent overgrazing of the understory serviceberry, and tall Oregongrape. and damage to the soil. Grazing should be delayed until the On the basis of a 100-year site curve, the mean site more desirable forage plants have achieved enough growth index for Douglas fir is 130. The yield at culmination of the to withstand grazing pressure and the soil is firm enough to mean annual increment is 7,740 cubic feet per acre in a withstand trampling by livestock. fully stocked, even-aged stand of trees at 60 years and Thinning, logging, and fire reduce the density of the 58,520 board feet per acre (Scribner rule) at 110 years. On overstory canopy and increase the production of the basis of a 50-year curve, the mean site index is 95. understory vegetation. Areas that support a large amount On the basis of a 50-year site curve, the mean site index of competing vegetation can be improved by prescribed for white fir is 80. The yield at culmination of the mean burning or by chemical or mechanical treatment. Seeding annual increment is 13,720 cubic feet per acre in a fully disturbed areas to suitable plants increases forage stocked, even-aged stand of trees at 70 years. production and reduces the risk of erosion. The main limitations affecting timber production are the The vegetative site is Mixed Fir-Western Hemlock slope, erosion, compaction, plant competition, and Forest. seedling mortality. Also, the bedrock restricts root growth. As a result, windthrow is a hazard. 46G-Donegan gravelly loam, 35 to 65 percent south Wheeled and tracked logging equipment can be used in slopes. This moderately deep, well drained soil is on the less sloping areas, but cable yarding generally is safer hillslopes. It formed in colluvium derived from igneous rock and results in less surface disturbance. If the soil is and volcanic ash. Elevation is 4,000 to 5,100 feet. The excessively disturbed when timber is harvested or logging mean annual precipitation is 40 to 50 inches, the mean roads are built, a larger number of rock fragments is left on annual temperature is 41 to 45 degrees F, and the average the surface. Using standard wheeled and tracked equipment frost-free period is less than 100 days. The native when the soil is moist causes rutting and compaction. vegetation is mainly conifers and an understory of grasses, Puddling can occur when the soil is wet. Using low-pressure shrubs, and forbs. ground equipment causes less damage to the soil and helps Typically, the surface is covered with a layer of needles, to maintain productivity. Compaction can be minimized by leaves, and twigs about 3 inches thick. The surface layer is using suitable methods of harvesting, laying out skid trails in dark brown gravelly loam about 10 inches thick. The next 12 advance, and harvesting timber when the soil is least inches also is dark brown gravelly loam. The subsoil is dark susceptible to compaction. Ripping skid trails and landings brown extremely gravelly loam about 10 inches thick. when the soil is dry can improve the growth of plants. Weathered bedrock is at a depth of about 32 inches. The Properly designed road drainage systems that include depth to bedrock ranges from 20 to 40 inches. In some carefully located culverts help to control erosion. Seeding, areas the surface layer is stony. mulching, and benching areas that have been cut and filled Included in this unit are small areas of Killet soils on also help to control erosion. Steep yarding paths, skid trails, concave slopes, soils that are similar to Killet soils but have and firebreaks are subject to rilling and gullying unless they bedrock within a depth of 60 inches, Rock outcrop on are protected by a plant cover or adequate water bars, or convex slopes, and soils that are similar to the Donegan soil both. Cutbanks occasionally slump when the soil is but have bedrock at a depth of more than 40 inches. Also saturated. included are small areas of Donegan soils that have slopes Constructing logging roads on the steeper slopes can of less than 35 or more than 65 percent. Included areas result in a high risk of erosion. Building the roads at make up about 20 percent of the total acreage. midslope requires extensive cutting and filling and removes Permeability is moderately slow in the Donegan soil. land from production. Material that is discarded when the Available water capacity is about 4 inches. The effective roads are built can damage vegetation and is a potential rooting depth is 20 to 40 inches. Runoff is rapid, and the source of sedimentation. If the material becomes saturated, hazard of water erosion is high. avalanches of debris can occur. End hauling of the waste This unit is used for timber production, livestock material minimizes damage to the vegetation downslope grazing, and wildlife habitat. and reduces the risk of sedimentation. Skid trails and This unit is suited to the production of Douglas fir and unsurfaced roads may be impassable during rainy periods. white fir. Other species that grow on this unit include Logging roads require suitable surfacing for year-round use. incense cedar, sugar pine, and Pacific madrone. Undesirable plants limit natural or artificial reforestation unless intensive site preparation and percent Killet soil. The components of this unit occur as maintenance measures are applied. Reforestation can be areas so intricately intermingled that mapping them accomplished by planting ponderosa pine and Douglas fir separately was not practical at the scale used. seedlings. Mulching around seedlings helps to maintain the Included in this unit are small areas of poorly drained moisture supply in summer and minimizes competition soils near drainageways and on concave slopes, soils that from undesirable understory plants. are similar to the Killet soil but have bedrock within a depth A high temperature in the surface layer during summer of 60 inches, and soils that are similar to the Donegan soil and the low available water capacity increase the seedling but have bedrock at a depth of more than 40 inches. Also mortality rate. The large number of rock fragments in the included are small areas of Donegan and Killet soils that soil also increases the seedling mortality rate. To have slopes of less than 3 or more than 12 percent. compensate for the expected high mortality rate, the larger Included areas make up about 20 percent of the total seedlings or a greater number of seedlings should be acreage. planted. When the timber is harvested, leaving some of the The Donegan soil is moderately deep and well drained. It larger trees unharvested provides shade for seedlings. The formed in colluvium derived dominantly from andesite and seedling mortality rate also can be reduced by providing volcanic ash. Typically, the surface is covered with a layer of artificial shade for seedlings. needles, leaves, and twigs about 3 inches thick. The surface Severe frost can damage or kill seedlings. Proper timber layer is dark brown gravelly loam about 10 inches thick. The harvesting methods can reduce the effect of frost on next 12 inches also is dark brown gravelly loam. The subsoil regeneration. is dark brown extremely gravelly loam about 10 inches thick. The main limitations affecting livestock grazing are Weathered bedrock is at a depth of about 32 inches. The erosion, compaction, and the slope. The native vegetation depth to bedrock ranges from 20 to 40 inches. In some suitable for grazing includes western fescue, tall trisetum, areas the surface layer is stony. and Alaska oniongrass. If the understory is overgrazed, the Permeability is moderately slow in the Donegan soil. proportion of preferred forage plants decreases and the Available water capacity is about 4 inches. The effective proportion of less preferred forage plants increases. rooting depth is 20 to 40 inches. Runoff is slow, and the A planned grazing system that includes timely deferment hazard of water erosion is slight. of grazing, rotation grazing, and proper livestock distribution The Killet soil is very deep and well drained. It formed in helps to prevent overgrazing of the understory and damage colluvium derived dominantly from andesite and volcanic to the soil. Grazing should be delayed until the more ash. Typically, the surface is covered with a layer of desirable forage plants have achieved enough growth to needles, leaves, and twigs about 2 inches thick. The withstand grazing pressure and the soil is firm enough to surface layer is dark reddish brown gravelly loam about 18 withstand trampling by livestock. inches thick. The upper 20 inches of the subsoil is dark Thinning, logging, and fire reduce the density of the reddish brown gravelly clay loam. The lower 22 inches is overstory canopy and increase the production of dark reddish brown clay loam. The depth to bedrock is 60 understory vegetation. Areas that support a large amount inches or more. In some areas the surface layer is stony. of competing vegetation can be improved by prescribed Permeability is moderately slow in the Killet soil. burning or by chemical or mechanical treatment. Seeding Available water capacity is about 9 inches. The effective disturbed areas to suitable plants increases forage rooting depth is 60 inches or more. Runoff is slow, and the production and reduces the risk of erosion. hazard of water erosion is slight. The vegetative site is Mixed Fir-Mixed Pine Forest. This unit is used for timber production, livestock grazing, and wildlife habitat. 47C-Donegan-Killet gravelly loams, 3 to 12 percent This unit is suited to the production of Douglas fir and slopes. This map unit is on plateaus. Elevation is 4,000 to white fir. Other species that grow on this unit include 5,100 feet. The mean annual precipitation is 40 to 50 incense cedar, western hemlock, and Pacific dogwood. inches, the mean annual temperature is 41 to 45 degrees The understory vegetation includes cascade F, and the average frost-free period is less than 100 days. Oregongrape, vine maple, and deerfoot vanillaleaf. The native vegetation is mainly conifers and an understory On the basis of a 100-year site curve, the mean site of grasses, shrubs, and forbs. index for Douglas fir is 140 on the Donegan soil. The yield This unit is about 60 percent Donegan soil and 20 at culmination of the mean annual increment is 8,700 cubic feet per acre in a fully stocked, even-aged stand of trees at 60 years and 69,410 board feet per acre (Scribner rule) at 110 years. On the basis of a 50year harvesting methods can reduce the effect of frost on curve, the mean site index is 105. regeneration. On the basis of a 50-year site curve, the mean site The main limitation affecting livestock grazing is index for white fir is 85 on the Donegan soil. The yield at compaction. The native vegetation suitable for grazing culmination of the mean annual increment is 14,420 cubic includes western fescue, mountain brome, and Alaska feet per acre in a fully stocked, even-aged stand of trees oniongrass. If the understory is overgrazed, the proportion at 70 years. of preferred forage plants decreases and the proportion of On the basis of a 100-year site curve, the mean site less preferred forage plants increases. index for Douglas fir is 150 on the Killet soil. The yield at A planned grazing system that includes timely deferment culmination of the mean annual increment is 9,480 cubic of grazing, rotation grazing, and proper livestock distribution feet per acre in a fully stocked, even-aged stand of trees at helps to prevent overgrazing of the understory and damage 60 years and 72,400 board feet per acre (Scribner rule) at to the soils. Grazing should be delayed until the more 100 years. On the basis of a 50-year curve, the mean site desirable forage plants have achieved enough growth to index is 115. withstand grazing pressure and the soils are firm enough to On the basis of a 50-year site curve, the mean site withstand trampling by livestock. index for white fir is 90 on the Killet soil. The yield at Thinning, logging, and fire reduce the density of the culmination of the mean annual increment is 15,190 cubic overstory canopy and increase the production of feet per acre in a fully stocked, even-aged stand of trees understory vegetation. Areas that support a large amount at 70 years. of competing vegetation can be improved by prescribed The main limitations affecting timber production are burning or by chemical or mechanical treatment. Seeding compaction, erosion, plant competition, and seedling disturbed areas to suitable plants increases forage mortality. Also, the bedrock underlying the Donegan soil production and reduces the risk of erosion. restricts root growth. As a result, windthrow is a hazard. The vegetative site is Mixed Fir-Western Hemlock Conventional methods of harvesting timber generally are Forest. suitable, but the soils may be compacted if they are moist when heavy equipment is used. Puddling can occur when 48E-Donegan-Killet gravelly loams, 12 to 35 the soils are wet. If the soils are excessively disturbed when percent north slopes. This map unit is on hillslopes. timber is harvested or logging roads are built, a larger Elevation is 4,000 to 5,100 feet. The mean annual number of rock fragments is left on the surface. Using precipitation is 40 to 50 inches, the mean annual low-pressure ground equipment causes less damage to the temperature is 41 to 45 degrees F, and the average soils and helps to maintain productivity. Compaction can be frost-free period is less than 100 days. The native minimized by using suitable methods of harvesting, laying vegetation is mainly conifers and an understory of out skid trails in advance, and harvesting timber when the grasses, shrubs, and forbs. soils are least susceptible to compaction. Ripping skid trails This unit is about 60 percent Donegan soil and 20 and landings when the soils are dry can improve the growth percent Killet soil. The components of this unit occur as of plants. areas so intricately intermingled that mapping them Erosion can be controlled by carefully planning the separately was not practical at the scale used. construction and maintenance of logging roads, skid trails, Included in this unit are small areas of poorly drained and landings. Seeding, mulching, and benching areas that soils near drainageways and on concave slopes, Rock have been cut and filled also help to control erosion. Skid outcrop on convex slopes, soils that are similar to the Killet trails and unsurfaced roads may be impassable during soil but have bedrock within a depth of 60 inches, and soils rainy periods. Logging roads require suitable surfacing for that are similar to the Donegan soil but have bedrock at a year-round use. depth of more than 40 inches. Also included are small areas Undesirable plants limit natural or artificial reforestation of Donegan and Killet soils that have slopes of less than 12 unless intensive site preparation and maintenance or more than 35 percent. Included areas make up about 20 measures are applied. Reforestation can be accomplished percent of the total acreage. by planting ponderosa pine and Douglas fir seedlings. The Donegan soil is moderately deep and well drained. It Mulching around seedlings helps to maintain the moisture formed in colluvium derived dominantly from andesite and supply in summer and minimizes competition from volcanic ash. Typically, the surface is covered with a layer of undesirable understory plants. needles, leaves, and twigs about 3 inches thick. The surface Severe frost can damage or kill seedlings. Air layer is dark brown gravelly drainage may be restricted on this unit. Proper timber loam about 10 inches thick. The next 12 inches also is cubic feet per acre in a fully stocked, even-aged stand of dark brown gravelly loam. The subsoil is dark brown trees at 70 years. extremely gravelly loam about 10 inches thick. Weathered The main limitations affecting timber production are bedrock is at a depth of about 32 inches. The depth to erosion, compaction, plant competition, and seedling bedrock ranges from 20 to 40 inches. In some areas the mortality. Wheeled and tracked logging equipment can be surface layer is stony. used in the less sloping areas, but cable yarding generally is Permeability is moderately slow in the Donegan soil. safer in the more sloping areas and results in less surface Available water capacity is about 4 inches. The effective disturbance. If the soils are excessively disturbed when rooting depth is 20 to 40 inches. Runoff is medium, and the timber is harvested or logging roads are built, a larger hazard of water erosion is moderate. number of rock fragments is left on the surface. Using The Killet soil is very deep and well drained. It formed in standard wheeled and tracked equipment when the soils are colluvium derived dominantly from andesite and volcanic moist causes rutting and compaction. Puddling can occur ash. Typically, the surface is covered with a layer of when the soils are wet. Using low-pressure ground needles, leaves, and twigs about 2 inches thick. The surface equipment causes less damage to the soils and helps to layer is dark reddish brown gravelly loam about 18 inches maintain productivity. Compaction can be minimized by using thick. The upper 20 inches of the subsoil is dark reddish suitable methods of harvesting, laying out skid trails in brown gravelly clay loam. The lower 22 inches is dark advance, and harvesting timber when the soils are least reddish brown clay loam. The depth to bedrock is 60 inches susceptible to compaction. Ripping skid trails and landings or more. In some areas the surface layer is stony. when the soils are dry can improve the growth of plants. Permeability is moderately slow in the Killet soil. Available Properly designed road drainage systems that include water capacity is about 9 inches. The effective rooting depth carefully located culverts help to control erosion. Seeding, is 60 inches or more. Runoff is medium, and the hazard of mulching, and benching areas that have been cut and filled water erosion is moderate. also help to control erosion. Steep yarding paths, skid trails, This unit is used for timber production, livestock and firebreaks are subject to rilling and gullying unless they grazing, and wildlife habitat. are protected by a plant cover or adequate water bars, or This unit is suited to the production of Douglas fir and both. Skid trails and unsurfaced roads may be impassable white fir. Other species that grow on this unit include during rainy periods. Logging roads require suitable incense cedar, western hemlock, and Pacific dogwood. surfacing for year-round use. The understory vegetation includes cascade Oregongrape, Undesirable plants limit natural or artificial reforestation vine maple, and deerfoot vanillaleaf. unless intensive site preparation and maintenance On the basis of a 100-year site curve, the mean site measures are applied. Reforestation can be accomplished index for Douglas fir is 140 on the Donegan soil. The yield by planting ponderosa pine and Douglas fir seedlings. at culmination of the mean annual increment is 8,700 cubic Mulching around seedlings helps to maintain the moisture feet per acre in a fully stocked, even-aged stand of trees at supply in summer and minimizes competition from 60 years and 69,410 board feet per acre (Scribner rule) at undesirable understory plants. 110 years. On the basis of a 50-year curve, the mean site Severe frost can damage or kill seedlings. In the less index is 105. sloping areas where air drainage may be restricted, proper On the basis of a 50-year site curve, the mean site index timber harvesting methods can reduce the effect of frost on for white fir is 85 on the Donegan soil. The yield at regeneration. culmination of the mean annual increment is 14,420 cubic The main limitations affecting livestock grazing are feet per acre in a fully stocked, even-aged stand of trees at compaction and erosion. The native vegetation suitable for 70 years. grazing includes western fescue, mountain brome, and On the basis of a 100-year site curve, the mean site Alaska oniongrass. If the understory is overgrazed, the index for Douglas fir is 150 on the Killet soil. The yield at proportion of preferred forage plants decreases and the culmination of the mean annual increment is 9,480 cubic proportion of less preferred forage plants increases. feet per acre in a fully stocked, even-aged stand of trees at A planned grazing system that includes timely deferment 60 years and 72,400 board feet per acre (Scribner rule) at of grazing, rotation grazing, and proper livestock distribution 100 years. On the basis of a 50-year curve, the mean site helps to prevent overgrazing of the understory and damage index is 115. to the soils. Grazing should be delayed until the more On the basis of a 50-year site curve, the mean site desirable forage plants have index for white fir is 90 on the Killet soil. The yield at culmination of the mean annual increment is 15,190 achieved enough growth to withstand grazing pressure and a layer of needles, leaves, and twigs about 2 inches thick. the soils are firm enough to withstand trampling by The surface layer is dark reddish brown gravelly loam livestock. about 18 inches thick. The upper 20 inches of the subsoil is Thinning, logging, and fire reduce the density of the dark reddish brown gravelly clay loam. The lower 22 inches overstory canopy and increase the production of is dark reddish brown clay loam. The depth to bedrock is understory vegetation. Areas that support a large amount 60 inches or more. In some areas the surface layer is of competing vegetation can be improved by prescribed stony. burning or by chemical or mechanical treatment. Seeding Permeability is moderately slow in the Killet soil. disturbed areas to suitable plants increases forage Available water capacity is about 9 inches. The effective production and reduces the risk of erosion. rooting depth is 60 inches or more. Runoff is medium, and The vegetative site is Mixed Fir-Western Hemlock the hazard of water erosion is moderate. Forest. This unit is used for timber production, livestock grazing, and wildlife habitat. 49E-Donegan-Killet gravelly loams, 12 to 35 This unit is suited to the production of Douglas fir and percent south slopes. This map unit is on hillslopes. white fir. Other species that grow on this unit include Elevation is 4,000 to 5,100 feet. The mean annual incense cedar, sugar pine, and Pacific madrone. The precipitation is 40 to 50 inches, the mean annual understory vegetation includes Whipplevine, Pacific temperature is 41 to 45 degrees F, and the average serviceberry, and tall Oregongrape. frost-free period is less than 100 days. The native On the basis of a 100-year site curve, the mean site vegetation is mainly conifers and an understory of index for Douglas fir is 135 on the Donegan soil. The yield grasses, shrubs, and forbs. at culmination of the mean annual increment is 8,280 cubic This unit is about 60 percent Donegan soil and 20 feet per acre in a fully stocked, even-aged stand of trees at percent Killet soil. The components of this unit occur as 60 years and 63,910 board feet per acre (Scribner rule) at areas so intricately intermingled that mapping them 110 years. On the basis of a 50-year curve, the mean site separately was not practical at the scale used. index is 100. Included in this unit are small areas of poorly drained On the basis of a 50-year site curve, the mean site soils near drainageways and on concave slopes, Rock index for white fir is 80 on the Donegan soil. The yield at outcrop on convex slopes, soils that are similar to the Killet culmination of the mean annual increment is 13,720 cubic soil but have bedrock within a depth of 60 inches, and soils feet per acre in a fully stocked, even-aged stand of trees at that are similar to the Donegan soil but have bedrock at a 70 years. depth of more than 40 inches. Also included are small On the basis of a 100-year site curve, the mean site areas of Donegan and Killet soils that have slopes of less index for Douglas fir is 140 on the Killet soil. The yield at than 12 or more than 35 percent. Included areas make up culmination of the mean annual increment is 8,700 cubic about 20 percent of the total acreage. feet per acre in a fully stocked, even-aged stand of trees at The Donegan soil is moderately deep and well drained. It 60 years and 69,410 board feet per acre (Scribner rule) at formed in colluvium derived dominantly from andesite and 110 years. On the basis of a 50-year curve, the mean site volcanic ash. Typically, the surface is covered with a layer of index is 105. needles, leaves, and twigs about 3 inches thick. The surface On the basis of a 50-year site curve, the mean site layer is dark brown gravelly loam about 10 inches thick. The index for white fir is 85 on the Killet soil. The yield at next 12 inches also is dark brown gravelly loam. The subsoil culmination of the mean annual increment is 14,420 cubic is dark brown extremely gravelly loam about 10 inches thick. feet per acre in a fully stocked, even-aged stand of trees Weathered bedrock is at a depth of about 32 inches. The at 70 years. depth to bedrock ranges from 20 to 40 inches. In some The main limitations affecting timber production are areas the surface layer is stony. erosion, compaction, plant competition, and seedling Permeability is moderately slow in the Donegan soil. mortality. Also, the bedrock underlying the Donegan soil Available water capacity is about 4 inches. The effective restricts root growth. As a result, windthrow is a hazard. rooting depth is 20 to 40 inches. Runoff is medium, and the Wheeled and tracked logging equipment can be used in hazard of water erosion is moderate. the less sloping areas, but cable yarding generally is safer in The Killet soil is very deep and well drained. It formed in the more sloping areas and results in less surface colluvium derived dominantly from andesite and volcanic disturbance. If the soils are excessively disturbed when ash. Typically, the surface is covered with timber is harvested or logging roads are built, a larger number of rock fragments is left on the surface. Using standard wheeled and tracked equipment when the soils are moist causes rutting and compaction. Puddling can occur when the soils are wet. Thinning, logging, and fire reduce the density of the Using low-pressure ground equipment causes less damage overstory canopy and increase the production of to the soils and helps to maintain productivity. Compaction understory vegetation. Areas that support a large amount can be minimized by using suitable methods of harvesting, of competing vegetation can be improved by prescribed laying out skid trails in advance, and harvesting timber burning or by chemical or mechanical treatment. Seeding when the soils are least susceptible to compaction. Ripping disturbed areas to suitable plants increases forage skid trails and landings when the soils are dry can improve production and reduces the risk of erosion. the growth of plants. The vegetative site is Mixed Fir-Mixed Pine Forest. Properly designed road drainage systems that include carefully located culverts help to control erosion. Seeding, 50E-Dubakella very stony clay loam, rocky, 12 to 35 mulching, and benching areas that have been cut and filled percent slopes. This moderately deep, well drained soil is also help to control erosion. Steep yarding paths, skid trails, on hillslopes. It formed in colluvium derived dominantly from and firebreaks are subject to rilling and gullying unless they peridotite and serpentinite. Elevation is 1,200 to 4,100 feet. are protected by a plant cover or adequate water bars, or The mean annual precipitation is 35 to 60 inches, the mean both. Skid trails and unsurfaced roads may be impassable annual temperature is 45 to 52 degrees F, and the average during rainy periods. Logging roads require suitable frost-free period is 100 to 160 days. The native vegetation is surfacing for year-round use. mainly conifers and hardwoods and an understory of Undesirable plants limit natural or artificial reforestation grasses, shrubs, and forbs. unless intensive site preparation and maintenance Typically, the surface layer is dark reddish brown very measures are applied. Reforestation can be accomplished stony clay loam about 11 inches thick. The subsoil is dark by planting ponderosa pine and Douglas fir seedlings. reddish brown very cobbly clay about 20 inches thick. Mulching around seedlings helps to maintain the moisture Bedrock is at a depth of about 31 inches. The depth to supply in summer and minimizes competition from bedrock ranges from 20 to 40 inches. undesirable understory plants. Included in this unit are small areas of Pearsoll soils and A high temperature in the surface layer and an Rock outcrop on ridges and convex slopes; Acker, insufficient moisture supply in summer increase the Gravecreek, Josephine, Norling, and Speaker soils; and, seedling mortality rate. The large number of rock fragments on concave slopes and foot slopes, soils that are similar to in the Donegan soil also increases the seedling mortality the Dubakella soil but have bedrock at a depth of more rate. To compensate for the expected high mortality rate, than 40 inches. Also included are Dubakella soils that have the larger seedlings or a greater number of seedlings slopes of less than 12 or more than 35 percent. Included should be planted. When the timber is harvested, leaving areas make up about 25 percent of the total acreage. some of the larger trees unharvested provides shade for Permeability is slow in the Dubakella soil. Available seedlings. water capacity is about 3 inches. The effective rooting Severe frost can damage or kill seedlings. In the less depth is 20 to 40 inches. Runoff is medium, and the sloping areas where air drainage may be restricted, proper hazard of water erosion is moderate or high. timber harvesting methods can reduce the effect of frost on This unit is used for timber production and wildlife regeneration. habitat. It is poorly suited to timber production. The The main limitations affecting livestock grazing are species that grow on this unit include Douglas fir, incense compaction and erosion. The native vegetation suitable for cedar, Jeffrey pine, and Pacific madrone. The understory grazing includes western fescue, tall trisetum, and Alaska vegetation includes canyon live oak, common snowberry, oniongrass. If the understory is overgrazed, the proportion and California fescue. of preferred forage plants decreases and the proportion of On the basis of a 100-year site curve, the mean site less preferred forage plants increases. index for Douglas fir is 80. The yield at culmination of the A planned grazing system that includes timely deferment mean annual increment is 4,060 cubic feet per acre in a of grazing, rotation grazing, and proper livestock distribution fully stocked, even-aged stand of trees at 70 years and helps to prevent overgrazing of the understory and damage 23,360 board feet per acre (Scribner rule) at 160 years. On to the soils. Grazing should be delayed until the more the basis of a 50-year curve, the mean site index is 60. desirable forage plants have achieved enough growth to The main limitations affecting timber production are low withstand grazing pressure and the soils are firm enough to fertility, erosion, compaction, seedling mortality, and plant withstand trampling by livestock. competition. When timber is harvested, management that minimizes The vegetative site is Douglas Fir-Pine Forest, the risk of erosion is essential. Wheeled and tracked logging Serpentine. equipment can be used in the less sloping areas, but cable yarding generally is safer in the more sloping areas and 50G-Dubakella very stony clay loam, rocky, 35 to 70 results in less surface disturbance. Rock outcrop and stones percent slopes. This moderately deep, well drained soil is can cause breakage of falling timber and can hinder yarding. on hillslopes. It formed in colluvium derived dominantly from If the soil is excessively disturbed when timber is harvested peridotite and serpentinite. Elevation is 1,200 to 4,100 feet. or logging roads are built, a larger number of rock fragments The mean annual precipitation is 35 to 60 inches, the mean is left on the surface. Using standard wheeled and tracked annual temperature is 45 to 52 degrees F, and the average equipment when the soil is moist causes rutting and frost-free period is 100 to 160 days. The native vegetation is compaction. Puddling can occur when the soil is wet. Using mainly conifers and hardwoods and an understory of low-pressure ground equipment causes less damage to the grasses, shrubs, and forbs. soil and helps to maintain productivity. Compaction can be Typically, the surface layer is dark reddish brown very minimized by using suitable methods of harvesting, laying stony clay loam about 11 inches thick. The subsoil is dark out skid trails in advance, and harvesting timber when the reddish brown very cobbly clay about 20 inches thick. soil is least susceptible to compaction. Ripping skid trails Bedrock is at a depth of about 31 inches. The depth to and landings when the soil is dry can improve the growth of bedrock ranges from 20 to 40 inches. plants. Included in this unit are small areas of Pearsoll soils and Properly designed road drainage systems that include Rock outcrop on ridges and convex slopes; Acker, carefully located culverts help to control erosion. Areas that Beekman, Gravecreek, Josephine, Norling, and Speaker have been cut and filled are easily eroded unless they are soils; and, on concave slopes and foot slopes, soils that are treated. Seeding, mulching, and benching these areas help similar to the Dubakella soil but have bedrock at a depth of to control erosion. Steep yarding paths, skid trails, and more than 40 inches. Also included are small areas of firebreaks are subject to rilling and gullying unless they are Dubakella soils that have slopes of less than 35 or more protected by a plant cover or adequate water bars, or both. than 70 percent. Included areas make up about 25 percent Skid trails and unsurfaced roads may be impassable during of the total acreage. rainy periods. Logging roads require suitable surfacing for Permeability is slow in the Dubakella soil. Available year-round use. Cutbanks occasionally slump when the soil water capacity is about 3 inches. The effective rooting is saturated. depth is 20 to 40 inches. Runoff is rapid, and the hazard A high temperature in the surface layer during summer, of water erosion is high. the large number of rock fragments in the soil, and the low This unit is used for timber production and wildlife available water capacity increase the seedling mortality habitat. It is poorly suited to timber production. The rate. A high content of magnesium and low content of species that grow on this unit include Douglas fir, incense calcium also increase the seedling mortality rate. To cedar, Jeffrey pine, and Pacific madrone. The understory compensate for the expected high mortality rate, the larger vegetation includes canyon live oak, common snowberry, seedlings or a greater number of seedlings should be and California fescue. planted. When the timber is harvested, leaving some of the On the basis of a 100-year site curve, the mean site larger trees unharvested provides shade for seedlings. index for Douglas fir is 80. The yield at culmination of the Reforestation can be accomplished by planting Jeffrey pine mean annual increment is 4,060 cubic feet per acre in a and incense cedar seedlings. fully stocked, even-aged stand of trees at 70 years and Undesirable plants limit natural or artificial 23,360 board feet per acre (Scribner rule) at 160 years. On reforestation unless intensive site preparation and the basis of a 50-year curve, the mean site index is 60. maintenance measures are applied. Mulching around The main limitations affecting timber production are the seedlings helps to maintain the moisture supply in slope, low fertility, erosion, compaction, seedling mortality, summer and minimizes competition from undesirable and plant competition. Also, the bedrock restricts root understory plants. growth. As a result, windthrow is a hazard. Increased erosion, loss of plant nutrients, and water When timber is harvested, management that minimizes repellency are likely to result from fires of moderate the risk of erosion is essential. Wheeled and tracked intensity. logging equipment can be used in the less sloping areas, but cable yarding generally is safer and results in less surface disturbance. Rock outcrop and stones can cause breakage of falling timber and can hinder yarding. If the soil is excessively disturbed when repellency are likely to result from fires of moderate timber is harvested or logging roads are built, a larger intensity. number of rock fragments is left on the surface. Using The vegetative site is Douglas Fir-Pine Forest, standard wheeled and tracked equipment when the soil is Serpentine. moist causes rutting and compaction. Puddling can occur when the soil is wet. Using low-pressure ground equipment 51C-Dumont gravelly clay loam, 1 to 12 percent causes less damage to the soil and helps to maintain slopes. This very deep, well drained soil is on foot slopes. productivity. Compaction can be minimized by using It formed in colluvium derived dominantly from metamorphic suitable methods of harvesting, laying out skid trails in rock. Elevation is 2,400 to 4,000 feet. The mean annual advance, and harvesting timber when the soil is least precipitation is 45 to 60 inches, the mean annual susceptible to compaction. Ripping skid trails and landings temperature is 45 to 50 degrees F, and the average when the soil is dry can improve the growth of plants. frost-free period is 100 to 160 days. The native vegetation Properly designed road drainage systems that include is mainly conifers and hardwoods and an understory of carefully located culverts help to control erosion Areas that grasses, shrubs, and forbs. have been cut and filled are easily eroded unless they are Typically, the surface is covered with a layer of needles, treated. Seeding, mulching, and benching these areas help leaves, and twigs about 1 inch thick, The surface layer is to control erosion. Steep yarding paths, skid trails, and dark reddish brown gravelly clay loam about 4 inches thick. firebreaks are subject to rilling and gullying unless they are The next layer is dark reddish brown clay loam about 11 protected by a plant cover or adequate water bars, or both. inches thick. The upper 36 inches of the subsoil is yellowish Cutbanks occasionally slump when the soil is saturated. red clay. The lower 9 inches is yellowish red clay loam. The Constructing logging roads on the steeper slopes can depth to bedrock is 60 inches or more. In some areas the result in a high risk of erosion. Building the roads at surface layer is stony. midslope requires extensive cutting and filling and removes Included in this unit are small areas of Acker soils, land from production. Material that is discarded when the Norling soils on the more sloping parts of the landscape and roads are built can damage vegetation and is a potential on convex slopes, and poorly drained soils near source of sedimentation. If the material becomes saturated, drainageways. Also included are small areas of Dumont avalanches of debris can occur. End hauling of the waste soils that have slopes of more than 12 percent. Included material minimizes damage to the vegetation downslope areas make up about 15 percent of the total acreage. and reduces the risk of sedimentation. Skid trails and Permeability is moderately slow in the Dumont soil. unsurfaced roads may be impassable during rainy periods. Available water capacity is about 9 inches. The effective Logging roads require suitable surfacing for year-round use. rooting depth is 60 inches or more. Runoff is slow, and the A high temperature in the surface layer during summer, hazard of water erosion is slight. the large number of rock fragments in the soil, and the low This unit is used for timber production and wildlife available water capacity increase the seedling mortality rate. habitat. It is suited to the production of Douglas fir. Other A high content of magnesium and low content of calcium species that grow on this unit include incense cedar, also increase the seedling mortality rate. To compensate for western hemlock, and Pacific madrone. The understory the expected high mortality rate, the larger seedlings or a vegetation includes golden chinkapin, salal, and cascade greater number of seedlings should be planted. When the Oregongrape. timber is harvested, leaving some of the larger trees On the basis of a 100-year site curve, the mean site unharvested provides shade for seedlings. The seedling index for Douglas fir is 135. The yield at culmination of the mortality rate also can be reduced by providing artificial mean annual increment is 8,280 cubic feet per acre in a shade for seedlings. Reforestation can be accomplished by fully stocked, even-aged stand of trees at 60 years and planting Jeffrey pine and incense cedar seedlings. 63,910 board feet per acre (Scribner rule) at 110 years. On Undesirable plants limit natural or artificial the basis of a 50-year curve, the mean site index is 100. reforestation unless intensive site preparation and The main limitations affecting timber production are maintenance measures are applied. Mulching around compaction, erosion, and plant competition. Conventional seedlings helps to maintain the moisture supply in methods of harvesting timber generally are suitable, but the summer and minimizes competition from undesirable soil may be compacted if it is moist when heavy equipment understory plants. is used. Puddling can occur when the soil is wet. Using Increased erosion, loss of plant nutrients, and water low-pressure ground equipment causes less damage to the soil and helps to maintain productivity. Compaction can be minimized by using suitable methods of harvesting, laying out skid trails rooting depth is 60 inches or more. Runoff is slow, and the in advance, and harvesting timber when the soil is least hazard of water erosion is slight. susceptible to compaction. Ripping skid trails and landings The Coyata soil is moderately deep and well drained. It when the soil is dry can improve the growth of plants. formed in colluvium derived dominantly from andesite. Erosion can be controlled by carefully planning the Typically, the surface is covered with a layer of needles, construction and maintenance of logging roads, skid trails, leaves, and twigs about 1 1/2 inches thick. The surface layer and landings. Seeding, mulching, and benching areas that is dark reddish brown gravelly loam about 11 inches thick. have been cut and filled also help to control erosion. Skid The next layer is dark brown very cobbly clay loam about 10 trails and unsurfaced roads may be impassable during inches thick. The subsoil is dark brown extremely cobbly rainy periods. Logging roads require suitable surfacing for clay loam about 10 inches thick. Bedrock is at a depth of year-round use. about 31 inches. The depth to bedrock ranges from 20 to 40 Undesirable plants limit natural or artificial reforestation inches. In some areas the surface layer is cobbly or stony. unless intensive site preparation and maintenance Permeability is moderate in the Coyata soil. Available measures are applied. Reforestation can be water capacity is about 2 inches. The effective rooting depth accomplished by planting Douglas fir seedlings. Mulching is 20 to 40 inches. Runoff is slow, and the hazard of water around seedlings helps to maintain the moisture supply in erosion is slight. summer and minimizes competition from undesirable This unit is used for timber production, livestock understory plants. grazing, and wildlife habitat. The vegetative site is Mixed Fir-Salal (rhododendron) This unit is suited to the production of Douglas fir. Other Forest. species that grow on this unit include white fir, western hemlock, and golden chinkapin. The understory vegetation 52C-Dumont-Coyata gravelly loams, 1 to 12 percent includes vine maple, California hazel, and cascade slopes. This map unit is on plateaus. Elevation is 2,000 to Oregongrape. 4,000 feet. The mean annual precipitation is 40 to 50 On the basis of a 100-year site curve, the mean site inches, the mean annual temperature is 45 to 52 degrees index for Douglas fir is 140 on the Dumont soil. The yield at F, and the average frost-free period is 100 to 160 days. The culmination of the mean annual increment is 8,700 cubic native vegetation is mainly conifers and hardwoods and an feet per acre in a fully stocked, even-aged stand of trees at understory of grasses, shrubs, and forbs. 60 years and 69,410 board feet per acre (Scribner rule) at This unit is about 50 percent Dumont soil and 35 110 years. On the basis of a 50-year curve, the mean site percent Coyata soil. The components of this unit occur as index is 105. areas so intricately intermingled that mapping them On the basis of a 100-year site curve, the mean site separately was not practical at the scale used. index for Douglas fir is 130 on the Coyata soil. The yield at Included in this unit are small areas of Reinecke soils, culmination of the mean annual increment is 7,740 cubic Terrabella soils near drainageways and on concave slopes, feet per acre in a fully stocked, even-aged stand of trees at and soils that are similar to the Dumont soil but have more 60 years and 58,520 board feet per acre (Scribner rule) at than 35 percent rock fragments or have bedrock within a 110 years. On the basis of a 50-year curve, the mean site depth of 60 inches. Also included are small areas of Dumont index is 100. and Coyata soils that have slopes of more than 12 percent. The main limitations affecting timber production are Included areas make up about 15 percent of the total compaction, erosion, plant competition, and seedling acreage. mortality. Also, the bedrock underlying the Coyata soil The Dumont soil is very deep and well drained. It restricts root growth. As a result, windthrow is a hazard. formed in residuum and colluvium derived dominantly Conventional methods of harvesting timber generally are from andesite. Typically, the surface is covered with a suitable, but the soils may be compacted if they are moist layer of needles, leaves, and twigs about 11/2 inches when heavy equipment is used. Puddling can occur when thick. The surface layer is dark reddish brown gravelly the soils are wet. If the soils are excessively disturbed when loam about 9 inches thick. The next layer is dark reddish timber is harvested or logging roads are built, a larger brown clay loam about 9 inches thick. The subsoil is dark number of rock fragments is left on the surface. Using reddish brown clay about 42 inches thick. The depth to low-pressure ground equipment causes less damage to the bedrock is 60 inches or more. In some areas the surface soils and helps to maintain productivity. Compaction can be layer is cobbly or stony. minimized by using suitable methods of harvesting, laying Permeability is moderately slow in the Dumont soil. out skid trails in advance, and harvesting timber when the Available water capacity is about 9 inches. The effective soils are least susceptible to compaction. Ripping skid trails and landings when the soils are dry can 53E-Dumont-Coyata gravelly loams, 12 to 35 improve the growth of plants. percent north slopes. This map unit is on hillslopes. Erosion can be controlled by carefully planning the Elevation is 2,000 to 4,000 feet. The mean annual construction and maintenance of logging roads, skid trails, precipitation is 40 to 50 inches, the mean annual and landings. Seeding, mulching, and benching areas that temperature is 45 to 52 degrees F, and the average have been cut and filled also help to control erosion. Skid frost-free period is 100 to 160 days. The native trails and unsurfaced roads may be impassable during vegetation is mainly conifers and hardwoods and an rainy periods. Logging roads require suitable surfacing for understory of grasses, shrubs, and forbs. year-round use. This unit is about 55 percent Dumont soil and 25 Undesirable plants limit natural or artificial reforestation percent Coyata soil. The components of this unit occur as unless intensive site preparation and maintenance areas so intricately intermingled that mapping them measures are applied. Reforestation can be accomplished separately was not practical at the scale used. by planting Douglas fir and ponderosa pine seedlings. Included in this unit are small areas of Reinecke soils, Mulching around seedlings helps to maintain the moisture Alcot and Crater Lake soils on concave slopes, Terrabella supply in summer and minimizes competition from soils near drainageways and on concave slopes, Rock undesirable understory plants. outcrop on ridges and convex slopes, and soils that are A high temperature in the surface layer and an similar to the Dumont soil but have more than 35 percent insufficient moisture supply in summer increase the seedling rock fragments or have bedrock within a depth of 60 mortality rate. The large number of rock fragments in the inches. Also included are small areas of Dumont and Coyata soil also increases the seedling mortality rate. To Coyata soils that have slopes of less than 12 or more than compensate for the expected high mortality rate, the larger 35 percent. Included areas make up about 20 percent of seedlings or a greater number of seedlings should be the total acreage. planted. When the timber is harvested, leaving some of the The Dumont soil is very deep and well drained. It formed larger trees unharvested provides shade for seedlings. in colluvium derived dominantly from andesite. Typically, the Severe frost can damage or kill seedlings. Air surface is covered with a layer of needles, leaves, and twigs drainage may be restricted on this unit. Proper timber about 1 1/2 inches thick. The surface layer is dark reddish harvesting methods can reduce the effect of frost on brown gravelly loam about 9 inches thick. The next layer is regeneration. dark reddish brown clay loam about 9 inches thick. The The main limitation affecting livestock grazing is subsoil is dark reddish brown clay about 42 inches thick. compaction. The native vegetation suitable for grazing The depth to bedrock is 60 inches or more. In some areas includes western fescue, mountain brome, and Alaska the surface layer is cobbly or stony. oniongrass. If the understory is overgrazed, the proportion Permeability is moderately slow in the Dumont soil. of preferred forage plants decreases and the proportion of Available water capacity is about 9 inches. The effective less preferred forage plants increases. rooting depth is 60 inches or more. Runoff is medium, and A planned grazing system that includes timely deferment the hazard of water erosion is moderate. of grazing, rotation grazing, and proper livestock distribution The Coyata soil is moderately deep and well drained. It helps to prevent overgrazing of the understory and damage formed in colluvium derived dominantly from andesite. to the soils. Grazing should be delayed until the more Typically, the surface is covered with a layer of needles, desirable forage plants have achieved enough growth to leaves, and twigs about 1 1/2 inches thick. The surface layer withstand grazing pressure and the soils are firm enough to is dark reddish brown gravelly loam about 11 inches thick. withstand trampling by livestock. The next layer is dark brown very cobbly clay loam about 10 Thinning, logging, and fire reduce the density of the inches thick. The subsoil is dark brown extremely cobbly overstory canopy and increase the production of clay loam about 10 inches thick. Bedrock is at a depth of understory vegetation. Areas that support a large amount about 31 inches. The depth to bedrock ranges from 20 to 40 of competing vegetation can be improved by prescribed inches. In some areas the surface layer is cobbly or stony. burning or by chemical or mechanical treatment. Seeding Permeability is moderate in the Coyata soil. Available disturbed areas to suitable plants increases forage water capacity is about 2 inches. The effective rooting depth production and reduces the risk of erosion. is 20 to 40 inches. Runoff is medium, and the hazard of The vegetative site is Mixed Fir-Western Hemlock water erosion is moderate. Forest. This unit is used for timber production, livestock grazing, and wildlife habitat. This unit is suited to the production of Douglas fir. Other species that grow on this unit include white fir, maintain the moisture supply in summer and minimizes western hemlock, and golden chinkapin. The understory competition from undesirable understory plants. vegetation includes vine maple, California hazel, and A high temperature in the surface layer and an cascade Oregongrape. insufficient moisture supply in summer increase the seedling On the basis of a 100-year site curve, the mean site mortality rate. The large number of rock fragments in the index for Douglas fir is 140 on the Dumont soil. The yield Coyata soil also increases the seedling mortality rate. To at culmination of the mean annual increment is 8,700 cubic compensate for the expected high mortality rate, the larger feet per acre in a fully stocked, even-aged stand of trees at seedlings or a greater number of seedlings should be 60 years and 69,410 board feet per acre (Scribner rule) at planted. When the timber is harvested, leaving some of the 110 years. On the basis of a 50-year curve, the mean site larger trees unharvested provides shade for seedlings. index is 105. The main limitations affecting livestock grazing are On the basis of a 100-year site curve, the mean site compaction and erosion. The native vegetation suitable for index for Douglas fir is 130 on the Coyata soil. The yield at grazing includes western fescue, mountain brome, and culmination of the mean annual increment is 7,740 cubic Alaska oniongrass. If the understory is overgrazed, the feet per acre in a fully stocked, even-aged stand of trees at proportion of preferred forage plants decreases and the 60 years and 58,520 board feet per acre (Scribner rule) at proportion of less preferred forage plants increases. 110 years. On the basis of a 50-year curve, the mean site A planned grazing system that includes timely deferment index is 100. of grazing, rotation grazing, and proper livestock distribution The main limitations affecting timber production are helps to prevent overgrazing of the understory and damage erosion, compaction, plant competition, and seedling to the soils. Grazing should be delayed until the more mortality. Also, the bedrock underlying the Coyata soil desirable forage plants have achieved enough growth to restricts root growth. As a result, windthrow is a hazard withstand grazing pressure and the soils are firm enough to Wheeled and tracked logging equipment can be used in withstand trampling by livestock. the less sloping areas, but cable yarding generally is safer Thinning, logging, and fire reduce the density of the in the more sloping areas and results in less surface overstory canopy and increase the production of disturbance. If the soils are excessively disturbed when understory vegetation. Areas that support a large amount timber is harvested or logging roads are built, a larger of competing vegetation can be improved by prescribed number of rock fragments is left on the surface. Using burning or by chemical or mechanical treatment. Seeding standard wheeled and tracked equipment when the soils disturbed areas to suitable plants increases forage are moist causes rutting and compaction. Puddling can production and reduces the risk of erosion. occur when the soils are wet Using low-pressure ground The vegetative site is Mixed Fir-Western Hemlock equipment causes less damage to the soils and helps to Forest. maintain productivity. Compaction can be minimized by using suitable methods of harvesting, laying out skid trails in 53G-Dumont-Coyata gravelly loams, 35 to 60 advance, and harvesting timber when the soils are least percent north slopes. This map unit is on hillslopes. susceptible to compaction. Ripping skid trails and landings Elevation is 2,000 to 4,000 feet. The mean annual when the soils are dry can improve the growth of plants. precipitation is 40 to 50 inches, the mean annual Properly designed road drainage systems that include temperature is 45 to 52 degrees F, and the average carefully located culverts help to control erosion Seeding, frost-free period is 100 to 160 days. The native mulching, and benching areas that have been cut and filled vegetation is mainly conifers and hardwoods and an also help to control erosion. Steep yarding paths, skid trails, understory of grasses, shrubs, and forbs. and firebreaks are subject to rilling and gullying unless they This unit is about 50 percent Dumont soil and 35 are protected by a plant cover or adequate water, bars, or percent Coyata soil. The components of this unit occur as both. Skid trails and unsurfaced roads may be impassable areas so intricately intermingled that mapping them during rainy periods. Logging roads require suitable separately was not practical at the scale used. surfacing for year-round use. Included in this unit are small areas of Rock outcrop on Undesirable plants limit natural or artificial reforestation ridges and convex slopes and soils that are similar to the unless intensive site preparation and maintenance Dumont soil but have more than 35 percent rock fragments measures are applied. Reforestation can be accomplished or have bedrock within a depth of 60 inches. Also included by planting Douglas fir and ponderosa pine seedlings. are small areas of Dumont and Coyata soils that have Mulching around seedlings helps to slopes of less than 35 or more than 60 percent. Included areas make up about 15 percent of the seedling mortality. Also, the bedrock underlying the Coyata total acreage. soil restricts root growth. As a result, windthrow is a hazard. The Dumont soil is very deep and well drained. It formed Wheeled and tracked logging equipment can be used in in colluvium derived dominantly from andesite. Typically, the the less sloping areas, but cable yarding generally is safer surface is covered with a layer of needles, leaves, and twigs and results in less surface disturbance. If the soils are about 1 1/z inches thick. The surface layer is dark reddish excessively disturbed when timber is harvested or logging brown gravelly loam about 9 inches thick. The next layer is roads are built, a larger number of rock fragments is left on dark reddish brown clay loam about 9 inches thick. The the surface. Using standard wheeled and tracked equipment subsoil is dark reddish brown clay about 42 inches thick. when the soils are moist causes rutting and compaction. The depth to bedrock is 60 inches or more. In some areas Puddling can occur when the soils are wet. Using the surface layer is cobbly or stony. low-pressure ground equipment causes less damage to the Permeability is moderately slow in the Dumont soil. soils and helps to maintain productivity. Compaction can be Available water capacity is about 9 inches. The effective minimized by using suitable methods of harvesting, laying rooting depth is 60 inches or more. Runoff is rapid, and the out skid trails in advance, and harvesting timber when the hazard of water erosion is high. soils are least susceptible to compaction. Ripping skid trails The Coyata soil is moderately deep and well drained. It and landings when the soils are dry can improve the growth formed in colluvium derived dominantly from andesite. of plants. Typically, the surface is covered with a layer of needles, Properly designed road drainage systems that include leaves, and twigs about 1 1/2 inches thick. The surface carefully located culverts help to control erosion. Seeding, layer is dark reddish brown gravelly loam about 11 inches mulching, and benching areas that have been cut and filled thick. The next layer is dark brown very cobbly clay loam also help to control erosion. Steep yarding paths, skid trails, about 10 inches thick. The subsoil is dark brown extremely and firebreaks are subject to rilling and gullying unless they cobbly clay loam about 10 inches thick. Bedrock is at a are protected by a plant cover or adequate water bars, or depth of about 31 inches. The depth to bedrock ranges from both. Cutbanks occasionally slump when the soils are 20 to 40 inches. In some areas the surface layer is cobbly or saturated. stony. Constructing logging roads on the steeper slopes can Permeability is moderate in the Coyata soil. Available result in a high risk of erosion. Building the roads at water capacity is about 2 inches. The effective rooting depth midslope requires extensive cutting and filling and removes is 20 to 40 inches. Runoff is rapid, and the hazard of water land from production. Material that is discarded when the erosion is high. roads are built can damage vegetation and is a potential This unit is used for timber production, livestock source of sedimentation. If the material becomes saturated, grazing, and wildlife habitat. avalanches of debris can occur. End hauling of the waste This unit is suited to the production of Douglas fir. Other material minimizes damage to the vegetation downslope species that grow on this unit include white-fir, western and reduces the risk of sedimentation. Skid trails and hemlock, and golden chinkapin. The understory vegetation unsurfaced roads may be impassable during rainy periods. includes vine maple, California hazel, and cascade Logging roads require suitable surfacing for year-round use. Oregongrape. Undesirable plants limit natural or artificial reforestation On the basis of a 100-year site curve, the mean site unless intensive site preparation and maintenance index for Douglas fir is 140 on the Dumont soil. The yield at measures are applied. Reforestation can be accomplished culmination of the mean annual increment is 8,700 cubic by planting Douglas fir and ponderosa pine seedlings. feet per acre in a fully stocked, even-aged stand of trees at Mulching around seedlings helps to maintain the moisture 60 years and 69,410 board feet per acre (Scribner rule) at supply in summer and minimizes competition from 110 years. On the basis of a 50-year curve, the mean site undesirable understory plants. index is 105. A high temperature in the surface layer and an On the basis of a 100-year site curve, the mean site insufficient moisture supply in summer increase the seedling index for Douglas fir is 130 on the Coyata soil. The yield at mortality rate. The large number of rock fragments in the culmination of the mean annual increment is 7,740 cubic Coyata soil also increases the seedling mortality rate. To feet per acre in a fully stocked, even-aged stand of trees at compensate for the expected high mortality rate, the larger 60 years and 58,520 board feet per acre (Scribner rule) at seedlings or a greater number of seedlings should be 110 years. On the basis of a 50-year curve, the mean site planted. When the timber is index is 100. The main limitations affecting timber production are the slope, erosion, compaction, plant competition, and harvested, leaving some of the larger trees unharvested layer is dark reddish brown gravelly loam about 9 inches provides shade for seedlings. thick. The next layer is dark reddish brown clay loam about The main limitations affecting livestock grazing are 9 inches thick. The subsoil is dark reddish brown clay about erosion, compaction, and the slope. The native vegetation 42 inches thick. The depth to bedrock is 60 inches or more. suitable for grazing includes western fescue, mountain In some areas the surface layer is cobbly or stony. brome, and Alaska oniongrass. If the understory is overgrazed, the proportion of preferred forage plants Permeability is moderately slow in the Dumont soil. decreases and the proportion of less preferred forage Available water capacity is about 9 inches. The effective plants increases. rooting depth is 60 inches or more. Runoff is medium, and A planned grazing system that includes timely deferment the hazard of water erosion is moderate. of grazing, rotation grazing, and proper livestock distribution The Coyata soil is moderately deep and well drained. It helps to prevent overgrazing of the understory and damage formed in colluvium derived dominantly from andesite. to the soils. Grazing should be delayed until the more Typically, the surface is covered with a layer of needles, desirable forage plants have achieved enough growth to leaves, and twigs about 11/2 inches thick. The surface layer withstand grazing pressure and the soils are firm enough to is dark reddish brown gravelly loam about 11 inches thick. withstand trampling by livestock. The next layer is dark brown very cobbly clay loam about 10 Thinning, logging, and fire reduce the density of the inches thick. The subsoil is dark brown extremely cobbly overstory canopy and increase the production of clay loam about 10 inches thick. Bedrock is at a depth of understory vegetation. Areas that support a large amount about 31 inches. The depth to bedrock ranges from 20 to 40 of competing vegetation can be improved by prescribed inches. In some areas the surface layer is cobbly or stony. burning or by chemical or mechanical treatment. Seeding Permeability is moderate in the Coyata soil. Available disturbed areas to suitable plants increases forage water capacity is about 2 inches. The effective rooting depth production and reduces the risk of erosion. is 20 to 40 inches. Runoff is medium, and the hazard of The vegetative site is Mixed Fir-Western Hemlock water erosion is moderate. Forest. This unit is used for timber production, livestock grazing, and wildlife habitat. 54E-Dumont-Coyata gravelly loams, 12 to 35 This unit is suited to the production of Douglas fir. Other percent south slopes. This map unit is on hillslopes. species that grow on this unit include white fir, ponderosa Elevation is 2,000 to 4,000 feet. The mean annual pine, sugar pine, and Pacific madrone. The understory precipitation is 40 to 50 inches, the mean annual vegetation includes Pacific serviceberry, tall Oregongrape, temperature is 45 to 52 degrees F, and the average and western fescue. frost-free period is 100 to 160 days. The native On the basis of a 100-year site curve, the mean site vegetation is mainly conifers and hardwoods and an index for Douglas fir is 135 on the Dumont soil. The yield at understory of grasses, shrubs, and forbs. culmination of the mean annual increment is 8,280 cubic This unit is about 50 percent Dumont soil and 30 feet per acre in a fully stocked, even-aged stand of trees at percent Coyata soil. The components of this unit occur as 60 years and 63,910 board feet per acre (Scribner rule) at areas so intricately intermingled that mapping them 110 years. On the basis of a 50-year curve, the mean site separately was not practical at the scale used. index is 105. Included in this unit are small areas of Reinecke soils, On the basis of a 100-year site curve, the mean site Alcot and Crater Lake soils on concave slopes, Terrabella index for Douglas fir is 120 on the Coyata soil. The yield at soils near drainageways and on concave slopes, Rock culmination of the mean annual increment is 6,900 cubic outcrop on ridges and convex slopes, and soils that are feet per acre in a fully stocked, even-aged stand of trees at similar to the Dumont soil but have more than 35 percent 60 years and 52,440 board feet per acre (Scribner rule) at rock fragments or have bedrock within a depth of 60 120 years. On the basis of a 50-year curve, the mean site inches. Also included are small areas of Dumont and index is 90. Coyata soils that have slopes of less than 12 or more than The main limitations affecting timber production are 35 percent. Included areas make up about 20 percent of erosion, compaction, seedling mortality, and plant the total acreage. competition. Also, the bedrock underlying the Coyata soil The Dumont soil is very deep and well drained. It formed restricts root growth. As a result, windthrow is a hazard. in colluvium derived dominantly from andesite. Typically, the Wheeled and tracked logging equipment can be used in surface is covered with a layer of needles, leaves, and twigs the less sloping areas, but cable yarding generally is safer about 1 1/2 inches thick. The surface in the more sloping areas and results in less surface disturbance. If the soils are excessively disturbed and the soils are firm enough to withstand trampling by when timber is harvested or logging roads are built, a larger livestock. number of rock fragments is left on the surface. Using Thinning, logging, and fire reduce the density of the standard wheeled and tracked equipment when the soils overstory canopy and increase the production of are moist causes rutting and compaction. Puddling can understory vegetation. Areas that support a large amount occur when the soils are wet. Using low-pressure ground of competing vegetation can be improved by prescribed equipment causes less damage to the soils and helps to burning or by chemical or mechanical treatment. Seeding maintain productivity. Compaction can be minimized by disturbed areas to suitable plants increases forage using suitable methods of harvesting, laying out skid trails in production and reduces the risk of erosion. advance, and harvesting timber when the soils are least The vegetative site is Mixed Fir-Mixed Pine Forest. susceptible to compaction. Ripping skid trails and landings when the soils are dry can improve the growth of plants. 54G-Dumont-Coyata gravelly loams, 35 to 60 Properly designed road drainage systems that include percent south slopes. This map unit is on hillslopes. carefully located culverts help to control erosion. Seeding, Elevation is 2,000 to 4,000 feet. The mean annual mulching, and benching areas that have been cut and filled precipitation is 40 to 50 inches, the mean annual also help to control erosion. Steep yarding paths, skid trails, temperature is 45 to 52 degrees F, and the average and firebreaks are subject to rilling and gullying unless they frost-free period is 100 to 160 days. The native are protected by a plant cover or adequate water bars, or vegetation is mainly conifers and hardwoods and an both. Skid trails and unsurfaced roads may be impassable understory of grasses, shrubs, and forbs. during rainy periods. Logging roads require suitable This unit is about 50 percent Dumont soil and 35 surfacing for year-round use. percent Coyata soil. The components of this unit occur as A high temperature in the surface layer and an areas so intricately intermingled that mapping them insufficient moisture supply in summer increase the seedling separately was not practical at the scale used. mortality rate. The large number of rock fragments in the Included in this unit are small areas of Rock outcrop on Coyata soil also increases the seedling mortality rate. To ridges and convex slopes and soils that are similar to the compensate for the expected high mortality rate, the larger Dumont soil but have more than 35 percent rock fragments seedlings or a greater number of seedlings should be or have bedrock within a depth of 60 inches. Also included planted. When the timber is harvested, leaving some of the are small areas of Dumont and Coyata soils that have larger trees unharvested provides shade for seedlings. slopes of less than 35 or more than 60 percent. Included Reforestation can be accomplished by planting Douglas fir areas make up about 15 percent of the total acreage. and ponderosa pine seedlings. The Dumont soil is very deep and well drained. It formed Undesirable plants limit natural or artificial in colluvium derived dominantly from andesite. Typically, the reforestation unless intensive site preparation and surface is covered with a layer of needles, leaves, and twigs maintenance measures are applied. Mulching around about 1 1/2 inches thick. The surface layer is dark reddish seedlings helps to maintain the moisture supply in brown gravelly loam about 9 inches thick. The next layer is summer and minimizes competition from undesirable dark reddish brown clay loam about 9 inches thick. The understory plants. subsoil is dark reddish brown clay about 42 inches thick. The main limitations affecting livestock grazing are The depth to bedrock is 60 inches or more. In some areas compaction and erosion. The native vegetation suitable for the surface layer is cobbly or stony. grazing includes western fescue, tall trisetum, and Alaska Permeability is moderately slow in the Dumont soil. oniongrass. If the understory is overgrazed, the proportion Available water capacity is about 9 inches. The effective of preferred forage plants decreases and the proportion of rooting depth is 60 inches or more. Runoff is rapid, and the less preferred forage plants increases. hazard of water erosion is high. A planned grazing system that includes timely deferment The Coyata soil is moderately deep and well drained. It of grazing, rotation grazing, and proper livestock distribution formed in colluvium derived dominantly from andesite. helps to prevent overgrazing of the understory and damage Typically, the surface is covered with a layer of needles, to the soils. Grazing should be delayed until the more leaves, and twigs about 1 1/2 inches thick. The surface layer desirable forage plants have achieved enough growth to is dark reddish brown gravelly loam about 11 inches thick. withstand grazing pressure The next layer is dark brown very cobbly clay loam about 10 inches thick. The subsoil is dark brown extremely cobbly clay loam about 10 inches thick. Bedrock is at a depth of about 31 inches. The depth and gullying unless they are protected by a plant cover or to bedrock ranges from 20 to 40 inches. In some areas the adequate water bars, or both. Cutbanks occasionally slump surface layer is cobbly or stony. when the soils are saturated. Permeability is moderate in the Coyata soil. Available Constructing logging roads on the steeper slopes can water capacity is about 2 inches. The effective rooting depth result in a high risk of erosion. Building the roads at is 20 to 40 inches. Runoff is rapid, and the hazard of water midslope requires extensive cutting and filling and removes erosion is high. land from production. Material that is discarded when the This unit is used for timber production, livestock roads are built can damage vegetation and is a potential grazing, and wildlife habitat. source of sedimentation. If the material becomes saturated, This unit is suited to the production of Douglas fir. Other avalanches of debris can occur. End hauling of the waste species that grow on this unit include white fir, ponderosa material minimizes damage to the vegetation downslope pine, sugar pine, and Pacific madrone. The understory and reduces the risk of sedimentation. Skid trails and vegetation includes Pacific serviceberry, tall Oregongrape, unsurfaced roads may be impassable during rainy periods. and western fescue. Logging roads require suitable surfacing for year-round use. On the basis of a 100-year site curve, the mean site A high temperature in the surface layer and an index for Douglas fir is 135 on the Dumont soil. The yield at insufficient moisture supply in summer increase the seedling culmination of the mean annual increment is 8,280 cubic mortality rate. The large number of rock fragments in the feet per acre in a fully stocked, even-aged stand of trees at Coyata soil also increases the seedling mortality rate. To 60 years and 63,910 board feet per acre (Scribner rule) at compensate for the expected high mortality rate, the larger 110 years. On the basis of a 50-year curve, the mean site seedlings or a greater number of seedlings should be index is 105. planted. When the timber is harvested, leaving some of the On the basis of a 100-year site curve, the mean site larger trees unharvested provides shade for seedlings. The index for Douglas fir is 120 on the Coyata soil. The yield at seedling mortality rate also can be reduced by providing culmination of the mean annual increment is 6,900 cubic artificial shade for seedlings. Reforestation can be feet per acre in a fully stocked, even-aged stand of trees at accomplished by planting Douglas fir and ponderosa pine 60 years and 52,440 board feet per acre (Scribner rule) at seedlings. 120 years. On the basis of a 50-year curve, the mean site Undesirable plants limit natural or artificial index is 90. reforestation unless intensive site preparation and The main limitations affecting timber production are the maintenance measures are applied. Mulching around slope, erosion, compaction, seedling mortality, and plant seedlings helps to maintain the moisture supply in competition. Also, the bedrock underlying the Coyata soil summer and minimizes competition from undesirable restricts root growth. As a result, windthrow is a hazard. understory plants. Wheeled and tracked logging equipment can be used in The main limitations affecting livestock grazing are the less sloping areas, but cable yarding generally is safer erosion, compaction, and the slope. The native vegetation and results in less surface disturbance. If the soils are suitable for grazing includes western fescue, tall trisetum, excessively disturbed when timber is harvested or logging and Alaska oniongrass. If the understory is overgrazed, the roads are built, a larger number of rock fragments is left on proportion of preferred forage plants decreases and the the surface. Using standard wheeled and tracked proportion of less preferred forage plants increases. equipment when the soils are moist causes rutting and A planned grazing system that includes timely deferment compaction. Puddling can occur when the soils are wet. of grazing, rotation grazing, and proper livestock distribution Using low-pressure ground equipment causes less damage helps to prevent overgrazing of the understory and damage to the soils and helps to maintain productivity. Compaction to the soils. Grazing should be delayed until the more can be minimized by using suitable methods of harvesting, desirable forage plants have achieved enough growth to laying out skid trails in advance, and harvesting timber withstand grazing pressure and the soils are firm enough to when the soils are least susceptible to compaction. Ripping withstand trampling by livestock. skid trails and landings when the soils are dry can improve Thinning, logging, and fire reduce the density of the the growth of plants. overstory canopy and increase the production of Properly designed road drainage systems that include understory vegetation. Areas that support a large amount carefully located culverts help to control erosion. Seeding, of competing vegetation can be improved by prescribed mulching, and benching areas that have been cut and filled burning or by chemical or mechanical treatment. Seeding also help to control erosion. Steep yarding paths, skid trails, disturbed areas to suitable plants and firebreaks are subject to rilling increases forage production and reduces the risk of grass-legume mixtures help to maintain fertility and tilth. erosion. Leaving crop residue on or near the surface helps to The vegetative site is Mixed Fir-Mixed Pine Forest. conserve moisture and control erosion. A tillage pan forms easily if the soil is tilled when wet. 55A-Evans loam, 0 to 3 percent slopes. This very Chiseling or subsoiling breaks up the pan. Surface crusting deep, well drained soil is on flood plains. It formed in and compaction can be minimized by returning crop residue alluvium derived from mixed sources. Elevation is 1,000 to to the soil. 3,000 feet. The mean annual precipitation is 18 to 40 Solid-set sprinkler irrigation is the best method of inches, the mean annual temperature is 50 to 54 degrees F, controlling frost and providing adequate moisture for tree and the average frost-free period is 150 to 180 days. The fruit. Compaction can be minimized by limiting the use of vegetation in areas that have not been cultivated is mainly equipment when the soil is wet and by planting a cover hardwoods and an understory of grasses, shrubs, and crop. A permanent sod crop helps to control runoff. forbs. Maintaining a protective plant cover in winter reduces the Typically, the surface layer is very dark brown loam soil loss resulting from flooding. Proper stocking rates, about 38 inches thick. The substratum to a depth of 60 pasture rotation, and restricted grazing during wet periods inches is dark brown loam. In some areas the surface help to keep pastures in good condition and protect the soil layer is gravelly or cobbly. from erosion. Grazing when the soil is wet results in Included in this unit are small areas of Abin, Camas, and compaction of the surface layer, poor tilth, and excessive Newberg soils and Riverwash; Cove soils on concave runoff. Periodic mowing and clipping help to maintain slopes; Central Point, Medford, and Takilma soils on uniform plant growth, discourage selective grazing, and terraces; and soils that are similar to the Evans soil but reduce the extent of clumpy growth. Fertilizer is needed to have a gravelly or very gravelly substratum. Also included ensure the optimum growth of grasses and legumes. are small areas of Evans soils that have slopes of more Grasses respond to nitrogen, and legumes respond to sulfur than 3 percent. Included areas make up about 20 percent and phosphorus. of the total acreage. The main hazard affecting homesite development is the Permeability is moderate in the Evans soil. Available flooding, which limits the suitability for septic tank water capacity is about 11 inches. The effective rooting absorption fields. Alternative waste disposal systems may depth is 60 inches or more. Runoff is slow, and the hazard function properly on this unit. Suitable included soils are of water erosion is slight. This soil is occasionally flooded throughout the unit. Onsite investigation is needed to for brief periods from December through March. locate such soils. Dikes and channels that have outlets for This unit is used mainly for irrigated crops, such as floodwater can protect buildings and onsite sewage alfalfa hay and small grain. Other crops include corn for disposal systems from flooding. silage and tree fruit. Some areas are used for grass-legume Revegetating as soon as possible helps to control hay, pasture, or homesite development. erosion in disturbed areas around construction sites. This unit is well suited to irrigated crops. It is limited Topsoil can be stockpiled and used to reclaim areas mainly by the hazard of flooding. This hazard can be disturbed during construction. Because of a low amount of reduced by levees, dikes, and diversions. rainfall in summer, irrigation is needed in areas that support In summer, irrigation is needed for the maximum lawn grasses, shrubs, vines, shade trees, or ornamental production of most crops. Furrow, border, corrugation, trees. trickle, and sprinkler irrigation systems are suitable. The Roads and streets should be constructed above the system used generally is governed by the crop that is expected level of flooding. The risk of flooding has been grown. For the efficient application and removal of surface reduced in some areas by the construction of large dams irrigation water, land leveling is needed. To prevent and reservoirs upstream. overirrigation and the leaching of plant nutrients, The vegetative site is Loamy Flood Plain, 18- to 30- applications of irrigation water should be adjusted to the inch precipitation zone. available water capacity, the rate of water intake, and the needs of the crop. Because the soil is droughty, the 56C-Farva very cobbly loam, 3 to 12 percent slopes. applications should be light and frequent. The use of pipe, This moderately deep, well drained soil is on plateaus. It ditch lining, or drop structures in irrigation ditches reduces formed in colluvium derived from andesite, basalt, and water loss and the hazard of erosion. volcanic ash. Elevation is 3,600 to 6,100 feet. The mean Returning all crop residue to the soil and using a annual precipitation is 30 to 55 inches, the mean annual cropping system that includes grasses, legumes, or temperature is 40 to 45 degrees F, and the average frost-free period is less than 100 days. The native vegetation is mainly conifers and an methods of harvesting, laying out skid trails in advance, and understory of grasses, shrubs, and forbs. harvesting timber when the soil is least susceptible to Typically, the surface is covered with a layer of needles, compaction. Ripping skid trails and landings when the soil leaves, and twigs about 1/2 inch thick. The surface layer is is dry can improve the growth of plants. dark brown very cobbly loam about 12 inches thick. The Erosion can be controlled by carefully planning the subsoil is brown extremely cobbly loam about 15 inches construction and maintenance of logging roads, skid trails, thick. The substratum also is brown extremely cobbly loam. and landings. Seeding, mulching, and benching areas that It is about 8 inches thick. Weathered bedrock is at a depth have been cut and filled also help to control erosion. Skid of about 35 inches. The depth to bedrock ranges from 20 to trails and unsurfaced roads may be impassable during 40 inches. In some areas the surface layer is stony. rainy periods. Logging roads require suitable surfacing for Included in this unit are small areas of Kanutchan and year-round use. Sibannac soils in basins and near drainageways; Bybee, Severe frost can damage or kill seedlings. Air Pinehurst, and Tatouche soils on concave slopes; drainage is restricted on this unit. Proper timber Woodseye soils and Rock outcrop on convex slopes; and harvesting methods can reduce the effect of frost on soils that are similar to the Farva soil but have bedrock at a regeneration. Reforestation can be accomplished by depth of more than 40 inches. Also included are small areas planting seedlings of frost-tolerant species, such as of Farva soils that have slopes of less than 3 or more than ponderosa pine and lodgepole pine. 12 percent. Included areas make up about 20 percent of the Undesirable plants limit natural or artificial total acreage. reforestation unless intensive site preparation and Permeability is moderately rapid in the Farva soil. maintenance measures are applied. Mulching around Available water capacity is about 3 inches. The effective seedlings helps to maintain the moisture supply in rooting depth is 20 to 40 inches. Runoff is slow, and the summer and minimizes competition from undesirable hazard of water erosion is slight. understory plants. This unit is used for timber production, livestock The main limitation affecting livestock grazing is grazing, and wildlife habitat. compaction. The native vegetation suitable for grazing This unit is suited to the production of Douglas fir and includes western fescue, mountain brome, tall trisetum, and white fir. Other species that grow on this unit include Pacific Alaska oniongrass. If the understory is overgrazed, the yew. The understory vegetation includes cascade proportion of preferred forage plants decreases and the Oregongrape and American twinflower. proportion of less preferred forage plants increases. On the basis of a 100-year site curve, the mean site A planned grazing system that includes timely deferment index for Douglas fir is 105. The yield at culmination of the of grazing, rotation grazing, and proper livestock distribution mean annual increment is 5,460 cubic feet per acre in a helps to prevent overgrazing of the understory and damage fully stocked, even-aged stand of trees at 60 years and to the soil. Grazing should be delayed until the more 45,600 board feet per acre (Scribner rule) at 150 years. On desirable forage plants have achieved enough growth to the basis of a 50-year curve, the mean site index is 80. withstand grazing pressure and the soil is firm enough to On the basis of a 50-year site curve, the mean site withstand trampling by livestock. index for white fir is 65. The yield at culmination of the Thinning, logging, and fire reduce the density of the mean annual increment is 10,150 cubic feet per acre in a overstory canopy and increase the production of fully stocked, even-aged stand of trees at 70 years. understory vegetation. Areas that support a large amount The main limitations affecting timber production are of competing vegetation can be improved by prescribed compaction, erosion, seedling mortality, and plant burning or by chemical or mechanical treatment. Seeding competition. Also, the bedrock restricts root growth. As a disturbed areas to suitable plants increases forage result, windthrow is a hazard. production and reduces the risk of erosion. Conventional methods of harvesting timber generally are The vegetative site is Mixed Fir-Yew Forest. suitable, but the soil may be compacted if it is moist when heavy equipment is used. Puddling can occur when the soil 57E-Farva very cobbly loam, 12 to 35 percent north is wet. If the soil is excessively disturbed when timber is slopes. This moderately deep, well drained soil is on harvested or logging roads are built, a larger number of rock hillslopes. It formed in colluvium derived from andesite, fragments is left on the surface. Using low-pressure ground basalt, and volcanic ash. Elevation is 3,600 to 6,100 feet. equipment causes less damage to the soil and helps to The mean annual precipitation is 30 to 55 inches, the mean maintain productivity. Compaction can be minimized by annual temperature is 40 to 45 degrees F, and the average using suitable frost-free period is less than 100 days. The native vegetation is mainly conifers Puddling can occur when the soil is wet. Using low- and an understory of grasses, shrubs, and forbs. pressure ground equipment causes less damage to the soil Typically, the surface is covered with a layer of needles, and helps to maintain productivity. Compaction can be leaves, and twigs about 1/2 inch thick. The surface layer is minimized by using suitable methods of harvesting, laying dark brown very cobbly loam about 12 inches thick. The out skid trails in advance, and harvesting timber when the subsoil is brown extremely cobbly loam about 15 inches soil is least susceptible to compaction. Ripping skid trails thick. The substratum also is brown extremely cobbly loam. and landings when the soil is dry can improve the growth of It is about 8 inches thick. Weathered bedrock is at a depth plants. of about 35 inches. The depth to bedrock ranges from 20 to Properly designed road drainage systems that include 40 inches. In some areas the surface layer is stony. carefully located culverts help to control erosion Seeding, Included in this unit are small areas of Kanutchan and mulching, and benching areas that have been cut and filled Sibannac soils in basins and near drainageways; Bybee, also help to control erosion. Steep yarding paths, skid trails, Pinehurst, and Tatouche soils on concave slopes; and firebreaks are subject to rilling and gullying unless they Woodseye soils and Rock outcrop on ridges and convex are protected by a plant cover or adequate water bars, or slopes; and soils that are similar to the Farva soil but have both. Skid trails and unsurfaced roads may be impassable bedrock at a depth of more than 40 inches. Also included during rainy periods. Logging roads require suitable are small areas of Farva soils that have slopes of less than surfacing for year-round use. 12 or more than 35 percent. Included areas make up about Undesirable plants limit natural or artificial reforestation 20 percent of the total acreage. unless intensive site preparation and maintenance Permeability is moderately rapid in the Farva soil. measures are applied. Reforestation can be accomplished Available water capacity is about 3 inches. The effective by planting ponderosa pine and Douglas fir seedlings. rooting depth is 20 to 40 inches. Runoff is medium, and the Mulching around seedlings helps to maintain the moisture hazard of water erosion is moderate. supply in summer and minimizes competition from This unit is used for timber production, livestock undesirable understory plants. grazing, and wildlife habitat. Severe frost can damage or kill seedlings. In the less This unit is suited to the production of Douglas fir and sloping areas where air drainage may be restricted, proper white fir. Other species that grow on this unit include Pacific timber harvesting methods can reduce the effect of frost on yew. The understory vegetation includes cascade regeneration. Oregongrape, and American twinflower. The main limitations affecting livestock grazing are On the basis of a 100-year site curve, the mean site compaction and erosion. The native vegetation suitable for index for Douglas fir is 110. The yield at culmination of the grazing includes western fescue, mountain brome, tall mean annual increment is 5,980 cubic feet per acre in a trisetum, and Alaska oniongrass. If the understory is fully stocked, even-aged stand of trees at 60 years and overgrazed, the proportion of preferred forage plants 48,300 board feet per acre (Scribner rule) at 140 years. On decreases and the proportion of less preferred forage plants the basis of a 50-year curve, the mean site index is 85. increases. On the basis of a 50-year site curve, the mean site A planned grazing system that includes timely deferment index for white fir is 65. The yield at culmination of the of grazing, rotation grazing, and proper livestock distribution mean annual increment is 10,150 cubic feet per acre in a helps to prevent overgrazing of the understory and damage fully stocked, even-aged stand of trees at 70 years. to the soil. Grazing should be delayed until the soil is firm The main limitations affecting timber production are and the more desirable forage plants have achieved enough erosion, compaction, plant competition, and seedling growth to withstand grazing pressure. mortality. Also, the bedrock restricts root growth. As a Thinning, logging, and fire reduce the density of the result, windthrow is a hazard. overstory canopy and increase the production of Wheeled and tracked logging equipment can be used in understory vegetation. Areas that support a large amount the less sloping areas, but cable yarding generally is safer of competing vegetation can be improved by prescribed in the more sloping areas and results in less surface burning or by chemical or mechanical treatment. Seeding disturbance. If the soil is excessively disturbed when timber disturbed areas to suitable plants increases forage is harvested or logging roads are built, a larger number of production and reduces the risk of erosion. rock fragments is left on the surface. Using standard The vegetative site is Mixed Fir-Yew Forest. wheeled and tracked equipment when the soil is moist causes rutting and compaction. 57G-Farva very cobbly loam, 35 to 65 percent north safer and results in less surface disturbance. If the soil is slopes. This moderately deep, well drained soil is on excessively disturbed when timber is harvested or logging hillslopes. It formed in colluvium derived from andesite, roads are built, a larger number of rock fragments is left on basalt, and volcanic ash. Elevation is 3,600 to 6,100 feet. the surface. Using standard wheeled and tracked The mean annual precipitation is 30 to 55 inches, the mean equipment when the soil is moist causes rutting and annual temperature is 40 to 45 degrees F, and the average compaction. Puddling can occur when the soil is wet. Using frost-free period is less than 100 days. The native low-pressure ground equipment causes less damage to the vegetation is mainly conifers and an understory of grasses, soil and helps to maintain productivity. Compaction can be shrubs, and forbs. minimized by using suitable methods of harvesting, laying Typically, the surface is covered with a layer of needles, out skid trails in advance, and harvesting timber when the leaves, and twigs about 1/2 inch thick. The surface layer is soil is least susceptible to compaction. Ripping skid trails dark brown very cobbly loam about 12 inches thick. The and landings when the soil is dry can improve the growth of subsoil is brown extremely cobbly loam about 15 inches plants. thick. The substratum also is brown extremely cobbly loam. Properly designed road drainage systems that include It is about 8 inches thick. Weathered bedrock is at a depth carefully located culverts help to control erosion Seeding, of about 35 inches. The depth to bedrock ranges from 20 to mulching, and benching areas that have been cut and filled 40 inches. In some areas the surface layer is stony. also help to control erosion. Steep yarding paths, skid trails, Included in this unit are small areas of Pinehurst and and firebreaks are subject to rilling and gullying unless they Tatouche soils on the less sloping parts of the landscape, are protected by a plant cover or adequate water bars, or Woodseye soils and Rock outcrop on ridges and convex both. Cutbanks occasionally slump when the soil is slopes, and soils that are similar to the Farva soil but have saturated. bedrock at a depth of more than 40 inches. Also included Constructing logging roads on the steeper slopes can are small areas of Farva soils that have slopes of less than result in a high risk of erosion. Building the roads at 35 or more than 65 percent. Included areas make up about midslope requires extensive cutting and filling and removes 20 percent of the total acreage. land from production. Material that is discarded when the Permeability is moderately rapid in the Farva soil. roads are built can damage vegetation and is a potential Available water capacity is about 3 inches. The effective source of sedimentation. If the material becomes saturated, rooting depth is 20 to 40 inches. Runoff is rapid, and the avalanches of debris can occur. End hauling of the waste hazard of water erosion is high. material minimizes damage to the vegetation downslope This unit is used for timber production, livestock and reduces the risk of sedimentation. Skid trails and grazing, and wildlife habitat. unsurfaced roads may be impassable during rainy periods. This unit is suited to the production of Douglas fir and Logging roads require suitable surfacing for year-round use. white fir. Other species that grow on this unit include Pacific Undesirable plants limit natural or artificial reforestation yew. The understory vegetation includes cascade unless intensive site preparation and maintenance Oregongrape, and American twinflower. measures are applied. Reforestation can be accomplished On the basis of a 100-year site curve, the mean site by planting ponderosa pine and Douglas fir seedlings. index for Douglas fir is 110. The yield at culmination of the Mulching around seedlings helps to maintain the moisture mean annual increment is 5,980 cubic feet per acre in a supply in summer and minimizes competition from fully stocked, even-aged stand of trees at 60 years and undesirable understory plants. 48,300 board feet per acre (Scribner rule) at 140 years. On Severe frost can damage or kill seedlings. Proper timber the basis of a 50-year curve, the mean site index is 85. harvesting methods can reduce the effect of frost on On the basis of a 50-year site curve, the mean site regeneration. index for white fir is 65. The yield at culmination of the The main limitations affecting livestock grazing are mean annual increment is 10,150 cubic feet per acre in a erosion, compaction, and the slope. The native vegetation fully stocked, even-aged stand of trees at 70 years. suitable for grazing includes western fescue, mountain The main limitations affecting timber production are the brome, tall trisetum, and Alaska oniongrass. If the slope, erosion, compaction, plant competition, and understory is overgrazed, the proportion of preferred forage seedling mortality. Also, the bedrock restricts root growth. plants decreases and the proportion of less preferred forage As a result, windthrow is a hazard. plants increases. Wheeled and tracked logging equipment can be used in A planned grazing system that includes timely the less sloping areas, but cable yarding generally is deferment of grazing, rotation grazing, and proper livestock distribution helps to prevent overgrazing of the understory vegetation includes Pacific serviceberry, tall understory and damage to the soil. Grazing should be Oregongrape, and common snowberry. delayed until the more desirable forage plants have On the basis of a 100-year site curve, the mean site achieved enough growth to withstand grazing pressure and index for Douglas fir is 100. The yield at culmination of the the soil is firm enough to withstand trampling by livestock. mean annual increment is 5,040 cubic feet per acre in a Thinning, logging, and fire reduce the density of the fully stocked, even-aged stand of trees at 60 years and overstory canopy and increase the production of 39,750 board feet per acre (Scribner rule) at 150 years. On understory vegetation. Areas that support a large amount the basis of a 50-year curve, the mean site index is 75. of competing vegetation can be improved by prescribed On the basis of a 50-year site curve, the mean site burning or by chemical or mechanical treatment. Seeding index for white fir is 65. The yield at culmination of the disturbed areas to suitable plants increases forage mean annual increment is 10,150 cubic feet per acre in a production and reduces the risk of erosion. fully stocked, even-aged stand of trees at 70 years. The vegetative site is Mixed Fir-Yew Forest. The main limitations affecting timber production are erosion, compaction, seedling mortality, and plant 58E-Farva very cobbly loam, 12 to 35 percent south competition. Also, the bedrock restricts root growth. As a slopes. This moderately deep, well drained soil is on result, windthrow is a hazard. hillslopes. It formed in colluvium derived from andesite, Wheeled and tracked logging equipment can be used in basalt, and volcanic ash. Elevation is 3,600 to 6,100 feet. the less sloping areas, but cable yarding generally is safer The mean annual precipitation is 30 to 55 inches, the mean in the more sloping areas and results in less surface annual temperature is 40 to 45 degrees F, and the average disturbance. If the soil is excessively disturbed when timber frost-free period is less than 100 days. The native is harvested or logging roads are built, a larger number of vegetation is mainly conifers and an understory of grasses, rock fragments is left on the surface. Using standard shrubs, and forbs. wheeled and tracked equipment when the soil is moist Typically, the surface is covered with a layer of needles, causes rutting and compaction. Puddling can occur when leaves, and twigs about 1/2 inch thick. The surface layer is the soil is wet. Using low-pressure ground equipment dark brown very cobbly loam about 12 inches thick. The causes less damage to the soil and helps to maintain subsoil is brown extremely cobbly loam about 15 inches productivity. Compaction can be minimized by using thick. The substratum also is brown extremely cobbly loam. suitable methods of harvesting, laying out skid trails in It is about 8 inches thick. Weathered bedrock is at a depth advance, and harvesting timber when the soil is least of about 35 inches. The depth to bedrock ranges from 20 to susceptible to compaction. Ripping skid trails and landings 40 inches. In some areas the surface layer is stony. when the soil is dry can improve the growth of plants. Included in this unit are small areas of Kanutchan and Properly designed road drainage systems that include Sibannac soils in basins and near drainageways; Bybee, carefully located culverts help to control erosion. Seeding, Pinehurst, and Tatouche soils on concave slopes; mulching, and benching areas that have been cut and filled Woodseye soils and Rock outcrop on ridges and convex also help to control erosion. Steep yarding paths, skid trails, slopes; and soils that are similar to the Farva soil but have and firebreaks are subject to rilling and gullying unless they bedrock at a depth of more than 40 inches. Also included are protected by a plant cover or adequate water bars, or are small areas of Farva soils that have slopes of less than both. Skid trails and unsurfaced roads may be impassable 12 or more than 35 percent. Included areas make up about during rainy periods. Logging roads require suitable 20 percent of the total acreage. surfacing for year-round use. Permeability is moderately rapid in the Farva soil. A high temperature in the surface layer during summer Available water capacity is about 3 inches. The effective and the low available water capacity increase the seedling rooting depth is 20 to 40 inches. Runoff is medium, and the mortality rate. The large number of rock fragments in the hazard of water erosion is moderate. soil also increases the seedling mortality rate. To This unit is used for timber production, livestock compensate for the expected high mortality rate, the larger grazing, and wildlife habitat. seedlings or a greater number of seedlings should be This unit is suited to the production of Douglas fir planted. When the timber is harvested, leaving some of the and white fir. Other species that grow on this unit larger trees unharvested provides shade for seedlings. include ponderosa pine and incense cedar. The Reforestation can be accomplished by planting ponderosa pine and Douglas fir seedlings. Severe frost can damage or kill seedlings. In the less Tatouche soils on the less sloping parts of the landscape, sloping areas where air drainage may be restricted, proper Woodseye soils and Rock outcrop on ridges and convex timber harvesting methods can reduce the effect of frost on slopes, and soils that are similar to the Farva soil but have regeneration. bedrock at a depth of more than 40 inches. Also included Undesirable plants limit natural or artificial are small areas of Farva soils that have slopes of less than reforestation unless intensive site preparation and 35 or more than 65 percent. Included areas make up about maintenance measures are applied. Mulching around 20 percent of the total acreage. seedlings helps to maintain the moisture supply in Permeability is moderately rapid in the Farva soil. summer and minimizes competition from undesirable Available water capacity is about 3 inches. The effective understory plants. rooting depth is 20 to 40 inches. Runoff is rapid, and the The main limitations affecting livestock grazing are hazard of water erosion is high. compaction and erosion. The native vegetation suitable for This unit is used for timber production, livestock grazing includes western fescue, mountain brome, tall grazing, and wildlife habitat. trisetum, and Alaska oniongrass. If the understory is This unit is suited to the production of Douglas fir and overgrazed, the proportion of preferred forage plants white fir. Other species that grow on this unit include decreases and the proportion of less preferred forage ponderosa pine and incense cedar. The understory plants increases. vegetation includes Pacific serviceberry, tall Oregongrape, A planned grazing system that includes timely deferment and common snowberry. of grazing, rotation grazing, and proper livestock distribution On the basis of a 100-year site curve, the mean site helps to prevent overgrazing of the understory and damage index for Douglas fir is 100. The yield at culmination of the to the soil. Grazing should be delayed until the more mean. annual increment is 5,040 cubic feet per acre in a desirable forage plants have achieved enough growth to fully stocked, even-aged stand of trees at 60 years and withstand grazing pressure and the soil is firm enough to 39,750 board feet per acre (Scribner rule) at 150 years. On withstand trampling by livestock. the basis of a 50-year curve, the mean site index is 70. Thinning, logging, and fire reduce the density of the On the basis of a 50-year site curve, the mean site index overstory canopy and increase the production of for white fir is 65. The yield at culmination of the mean understory vegetation. Areas that support a large amount annual increment is 10,150 cubic feet per acre in a fully of competing vegetation can be improved by prescribed stocked, even-aged stand of trees at 70 years. burning or by chemical or mechanical treatment. Seeding The main limitations affecting timber production are the disturbed areas to suitable plants increases forage slope, erosion, compaction, seedling mortality, and plant production and reduces the risk of erosion. competition. Also, the bedrock restricts root growth. As a The vegetative site is Mixed Fir-Serviceberry Forest. result, windthrow is a hazard. Wheeled and tracked logging equipment can be used in 58G-Farva very cobbly loam, 35 to 65 percent south the less sloping areas, but cable yarding generally is safer slopes. This moderately deep, well drained soil is on and results in less surface disturbance. If the soil is hillslopes. It formed in colluvium derived from andesite, excessively disturbed when timber is harvested or logging basalt, and volcanic ash. Elevation is 3,600 to 6,100 feet. roads are built, a larger number of rock fragments is left on The mean annual precipitation is 30 to 55 inches, the mean the surface. Using standard wheeled and tracked equipment annual temperature is 40 to 45 degrees F, and the average when the soil is moist causes rutting and compaction. frost-free period is less than 100 days. The native Puddling can occur when the soil is wet. Using low-pressure vegetation is mainly conifers and an understory of grasses, ground equipment causes less damage to the soil and helps shrubs, and forbs. to maintain productivity; Compaction can be minimized by Typically, the surface is covered with a layer of needles, using suitable methods of harvesting, laying out skid trails in leaves, and twigs about 1/2 inch thick. The surface layer is advance, and harvesting timber when the soil is least dark brown very cobbly loam about 12 inches thick. The susceptible to compaction. Ripping skid trails and landings subsoil is brown extremely cobbly loam about 15 inches when the soil is dry can improve the growth of plants. thick. The substratum also is brown extremely cobbly loam. Properly designed road drainage systems that include It is about 8 inches thick. Weathered bedrock is at a depth carefully located culverts help to control erosion. Seeding, of about 35 inches. The depth to bedrock ranges from 20 to mulching, and benching areas that have been cut and filled 40 inches. In some areas the surface layer is stony. also help to control erosion. Steep yarding Included in this unit are small areas of Pinehurst and paths, skid trails, and firebreaks are subject to rilling and understory vegetation. Areas that support a large amount gullying unless they are protected by a plant cover or of competing vegetation can be improved by prescribed adequate water bars, or both. Cutbanks occasionally slump burning or by chemical or mechanical treatment. Seeding when the soil is saturated. disturbed areas to suitable plants increases forage Constructing logging roads on the steeper slopes can production and reduces the risk of erosion. result in a high risk of erosion. Building the roads at The vegetative site is Mixed Fir-Serviceberry Forest. midslope requires extensive cutting and filling and removes land from production. Material that is discarded when the 59G-Farva -Rock outcrop complex, 35 to 70 roads are built can damage vegetation and is a potential percent north slopes. This map unit is on hillslopes. source of sedimentation. If the material becomes saturated, Elevation is 3,600 to 6,100 feet. The mean annual avalanches of debris can occur. End hauling of the waste precipitation is 30 to 55 inches, the mean annual material minimizes damage to the vegetation downslope temperature is 40 to 45 degrees F, and the average and reduces the risk of sedimentation. Skid trails and frost-free period is less than 100 days. The native unsurfaced roads may be impassable during rainy periods. vegetation is mainly conifers and an understory of Logging roads require suitable surfacing for year-round use. grasses, shrubs, and forbs. A high temperature in the surface layer during summer This unit is about 70 percent Farva soil and 20 percent and the low available water capacity increase the seedling Rock outcrop. The components of this unit occur as areas mortality rate. The large number of rock fragments in the so intricately intermingled that mapping them separately soil also increases the seedling mortality rate. To was not practical at the scale used. compensate for the expected high mortality rate, the larger Included in this unit are small areas of Pinehurst and seedlings or a greater number of seedlings should be Tatouche soils on the less sloping parts of the landscape, planted. When the timber is harvested, leaving some of the Woodseye soils on ridges and convex slopes, and soils that larger trees unharvested provides shade for seedlings. The are similar to the Farva soil but have bedrock at a depth of seedling mortality rate also can be reduced by providing more than 40 inches. Also included are small areas of Farva artificial shade for seedlings. Reforestation can be soils that have slopes of less than 35 or more than 70 accomplished by planting ponderosa pine and Douglas fir percent. Included areas make up about 10 percent of the seedlings. total acreage. Severe frost can damage or kill seedlings. Proper timber The Farva soil is moderately deep and well drained. It harvesting methods can reduce the effect of frost on formed in colluvium derived dominantly from andesite, regeneration. basalt, and volcanic ash. Typically, the surface is covered Undesirable plants limit natural or artificial with a layer of needles, leaves, and twigs about 1/2 inch reforestation unless intensive site preparation and thick. The surface layer is dark brown very cobbly loam maintenance measures are applied. Mulching around about 12 inches thick. The subsoil is brown extremely cobbly seedlings helps to maintain the moisture supply in loam about 15 inches thick. The substratum also is brown summer and minimizes competition from undesirable extremely cobbly loam. It is about 8 inches thick. Weathered understory plants. bedrock is at a depth of about 35 inches. The depth to The main limitations affecting livestock grazing are bedrock .ranges from 20 to 40 inches. In some areas the erosion, compaction, and the slope. The native vegetation surface layer is stony. suitable for grazing includes western fescue, mountain Permeability is moderately rapid in the Farva soil. brome, tall trisetum, and Alaska oniongrass. If the Available water capacity is about 3 inches. The effective understory is overgrazed, the proportion of preferred forage rooting depth is 20 to 40 inches. Runoff is rapid, and the plants decreases and the proportion of less preferred forage hazard of water erosion is high. plants increases. Rock outcrop consists of areas of exposed bedrock. A planned grazing system that includes timely deferment Runoff is very rapid in these areas. of grazing, rotation grazing, and proper livestock distribution This unit is used for timber production, livestock helps to prevent overgrazing of the understory and damage grazing, and wildlife habitat. to the soil. Grazing should be delayed until the more This unit is suited to the production of Douglas fir and desirable forage plants have achieved enough growth to white fir. Other species that grow on this unit include Pacific withstand grazing pressure and the soil is firm enough to yew. The understory vegetation includes cascade withstand trampling by livestock. Oregongrape and American twinflower. Thinning, logging, and fire reduce the density of the On the basis of a 100-year site curve, the mean site overstory canopy and increase the production of index for Douglas fir is 110 on the Farva soil. The yield at culmination of the mean annual increment is 5,980 be accomplished by planting ponderosa pine and Douglas cubic feet per acre in a fully stocked, even-aged stand of fir seedlings. Mulching around seedlings helps to maintain trees at 60 years and 48,300 board feet per acre (Scribner the moisture supply in summer and minimizes competition rule) at 140 years. On the basis of a 50-year curve, the from undesirable understory plants. mean site index is 85. Severe frost can damage or kill seedlings. Proper timber On the basis of a 50-year site curve, the mean site harvesting methods can reduce the effect of frost on index for white fir is 65 on the Farva soil. The yield at regeneration. culmination of the mean annual increment is 10,150 cubic The main limitations affecting livestock grazing are feet per acre in a fully stocked, even-aged stand of trees erosion, compaction, the slope, and the Rock outcrop. The at 70 years. native vegetation suitable for grazing includes western The main limitations affecting timber production are the fescue, mountain brome, tall trisetum, and Alaska slope, the Rock outcrop, erosion, compaction, plant oniongrass. If the understory is overgrazed, the proportion competition, and seedling mortality. Also, the bedrock of preferred forage plants decreases and the proportion of restricts root growth. As a result, windthrow is a hazard less preferred forage plants increases. Wheeled and tracked logging equipment can be used in A planned grazing system that includes timely the less sloping areas, but cable yarding generally is safer deferment of grazing, rotation grazing, and proper livestock and results in less surface disturbance. The Rock outcrop distribution helps to prevent overgrazing of the understory can cause breakage of falling timber and can hinder and damage to the soil. Grazing should be delayed until yarding. If the soil is excessively disturbed when timber is the more desirable forage plants have achieved enough harvested or logging roads are built, a larger number of rock growth to withstand grazing pressure and the soil is firm fragments is left on the surface. Using standard wheeled enough to withstand trampling by livestock. and tracked equipment when the soil is moist causes rutting Thinning, logging, and fire reduce the density of the and compaction. Puddling can occur when the soil is wet. overstory canopy and increase the production of Using low-pressure ground equipment causes less damage understory vegetation. Areas that support a large amount to the soil and helps to maintain productivity. Compaction of competing vegetation can be improved by prescribed can be minimized by using suitable methods of harvesting, burning or by chemical or mechanical treatment. Seeding laying out skid trails in advance, and harvesting timber when disturbed areas to suitable plants increases forage the soil is least susceptible to compaction. Ripping skid production and reduces the risk of erosion. trails and landings when the soil is dry can improve the Because of the slope and the Rock outcrop, areas of growth of plants. this unit can hinder livestock movement. Properly designed road drainage systems that include The vegetative site is Mixed Fir-Yew Forest. carefully located culverts help to control erosion Seeding, mulching, and benching areas that have been cut and filled 60G-Farva -Rock outcrop complex, 35 to 70 also help to control erosion. Steep yarding paths, skid trails, percent south slopes. This map unit is on hillslopes. and firebreaks are subject to rilling and gullying unless they Elevation is 3,600 to 6,100 feet. The mean annual are protected by a plant cover or adequate water bars, or precipitation is 30 to 55 inches, the mean annual both. Cutbanks occasionally slump when the soil is temperature is 40 to 45 degrees F, and the average saturated. frost-free period is less than 100 days. The native Constructing logging roads on the steeper slopes can vegetation is mainly conifers and an understory of result in a high risk of erosion. Building the roads at grasses, shrubs, and forbs. midslope requires extensive cutting and filling and removes This unit is about 70 percent Farva soil and 20 percent land from production. Material that is discarded when the Rock outcrop. The components of this unit occur as areas roads are built can damage vegetation and is a potential so intricately intermingled that mapping them separately source of sedimentation. If the material becomes saturated, was not practical at the scale used. avalanches of debris can occur. End hauling of the waste Included in this unit are small areas of Pinehurst and material minimizes damage to the vegetation downslope Tatouche soils on the less sloping parts of the landscape, and reduces the risk of sedimentation. Skid trails and Woodseye soils on ridges and convex slopes, and soils that unsurfaced roads may be impassable during rainy periods. are similar to the Farva soil but have bedrock at a depth of Logging roads require suitable surfacing for year-round use. more than 40 inches. Also included are small areas of Undesirable plants limit natural or artificial reforestation Farva soils that have slopes of less than 35 or more than unless intensive site preparation and maintenance 70 percent. Included areas measures are applied. Reforestation can make up about 10 percent of the total acreage. maintain productivity. Compaction can be minimized by The Farva soil is moderately deep and well drained. It using suitable methods of harvesting, laying out skid trails in formed in colluvium derived dominantly from andesite, advance, and harvesting timber when the soil is least basalt, and volcanic ash. Typically, the surface is covered susceptible to compaction. Ripping skid trails and landings with a layer of needles, leaves, and twigs about 1/2 inch when the soil is dry can improve the growth of plants. thick. The surface layer is dark brown very cobbly loam Properly designed road drainage systems that include about 12 inches thick. The subsoil is brown extremely carefully located culverts help to control erosion Seeding, cobbly loam about 15 inches thick. The substratum also is mulching, and benching areas that have been cut and filled brown extremely cobbly loam. It is about 8 inches thick. also help to control erosion. Steep yarding paths, skid trails, Weathered bedrock is at a depth of about 35 inches. The and firebreaks are subject to rilling and gullying unless they depth to bedrock ranges from 20 to 40 inches. In some are protected by a plant cover or adequate water bars, or areas the surface layer is stony. both. Cutbanks occasionally slump when the soil is Permeability is moderately rapid in the Farva soil. saturated. Available water capacity is about 3 inches. The effective Constructing logging roads on the steeper slopes can rooting depth is 20 to 40 inches. Runoff is rapid, and the result in a high risk of erosion. Building the roads at hazard of water erosion is high. midslope requires extensive cutting and filling and removes Rock outcrop consists of areas of exposed bedrock. land from production. Material that is discarded when the Runoff is very rapid in these areas. roads are built can damage vegetation and is a potential This unit is used for timber production, livestock source of sedimentation. If the material becomes saturated, grazing, and wildlife habitat. avalanches of debris can occur. End hauling of the waste This unit is suited to the production of Douglas fir and material minimizes damage to the vegetation downslope white fir. Other species that grow on this unit include and reduces the risk of sedimentation. Skid trails and ponderosa pine and incense cedar. The understory unsurfaced roads may be impassable during rainy periods. vegetation includes Pacific serviceberry, tall Oregongrape, Logging roads require suitable surfacing for year-round use. and common snowberry. A high temperature in the surface layer during summer On the basis of a 100-year site curve, the mean site and the low available water capacity increase the seedling index for Douglas fir is 100 on the Farva soil. The yield at mortality rate. The large number of rock fragments in the culmination of the mean annual increment is 5,040 cubic soil also increases the seedling mortality rate. To feet per acre in a fully stocked, even-aged stand of trees at compensate for the expected high mortality rate, the larger 60 years and 39,750 board feet per acre (Scribner rule) at seedlings or a greater number of seedlings should be 150 years. On the basis of a 50-year curve, the mean site planted. When the timber is harvested, leaving some of the index is 70. larger trees unharvested provides shade for seedlings. The On the basis of a 50-year site curve, the mean site seedling mortality rate also can be reduced by providing index for white fir is 65 on the Farva soil. The yield at artificial shade for seedlings. Reforestation can be culmination of the mean annual increment is 10,150 cubic accomplished by planting ponderosa pine and Douglas fir feet per acre in a fully stocked, even-aged stand of trees seedlings. at 70 years. Severe frost can damage or kill seedlings. Proper timber The main limitations affecting timber production are the harvesting methods can reduce the effect of frost on slope, the Rock outcrop, erosion, compaction, seedling regeneration. mortality, and plant competition. Also, the bedrock Undesirable plants limit natural or artificial restricts root growth. As a result, windthrow is a hazard. reforestation unless intensive site preparation and Wheeled and tracked logging equipment can be used in maintenance measures are applied. Mulching around the less sloping areas, but cable yarding generally is safer seedlings helps to maintain the moisture supply in and results in less surface disturbance. The Rock outcrop summer and minimizes competition from undesirable can cause breakage of falling timber and can hinder understory plants. yarding. If the soil is excessively disturbed when timber is The main limitations affecting livestock grazing are harvested or logging roads are built, a larger number of rock erosion, compaction, the slope, and the Rock outcrop. The fragments is left on the surface. Using standard wheeled native vegetation suitable for grazing includes western and tracked equipment when the soil is moist causes rutting fescue, mountain brome, tall trisetum, and Alaska and compaction. Puddling can occur when the soil is wet. oniongrass. If the understory is overgrazed, the proportion Using low-pressure ground equipment causes less damage of preferred forage plants decreases and the proportion of to the soil and helps to less preferred forage plants increases. A planned grazing system that includes timely deferment This unit is well suited to irrigated crops. It is limited of grazing, rotation grazing, and proper livestock distribution mainly by the moderately slow permeability. In summer, helps to prevent overgrazing of the understory and damage irrigation is needed for the maximum production of most to the soil. Grazing should be delayed until the more crops. Furrow, border, corrugation, trickle, and sprinkler desirable forage plants have achieved enough growth to irrigation systems are suitable. The system used generally withstand grazing pressure and the soil is firm enough to is governed by the crop that is grown. For the efficient withstand trampling by livestock. application and removal of surface irrigation water, land Thinning, logging, and fire reduce the density of the leveling is needed. To prevent overirrigation and excessive overstory canopy and increase the production of erosion, applications of irrigation water should be adjusted understory vegetation. Areas that support a large amount to the available water capacity, the rate of water intake, and of competing vegetation can be improved by prescribed the needs of the crop. The use of pipe, ditch lining, or drop burning or by chemical or mechanical treatment. Seeding structures in irrigation ditches reduces water loss and the disturbed areas to suitable plants increases forage hazard of erosion. production and reduces the risk of erosion. Returning all crop residue to the soil and using a Because of the slope and the Rock outcrop, areas of this cropping system that includes grasses, legumes, or unit can hinder livestock movement. grass-legume mixtures help to maintain fertility and tilth. The vegetative site is Mixed Fir-Serviceberry Forest. Leaving crop residue on or near the surface helps to conserve moisture and control erosion. 61A-Foehlin gravelly loam, 0 to 3 percent slopes. A tillage pan forms easily if the soil is tilled when wet. This very deep, well drained soil is on stream terraces. It Chiseling or subsoiling breaks up the pan. Surface crusting formed in alluvium derived dominantly from metamorphic and compaction can be minimized by returning crop residue rock. Elevation is 1,000 to 2,500 feet. The mean annual to the soil. precipitation is 25 to 35 inches, the mean annual Solid-set sprinkler irrigation is the best method of temperature is 50 to 54 degrees F, and the average controlling frost and providing adequate moisture for tree frost-free period is 140 to 180 days. The vegetation in areas fruit. Compaction can be minimized by limiting the use of that have not been cultivated is mainly grasses, shrubs, and equipment when the soil is wet and by planting a cover forbs. crop. A permanent cover crop helps to control runoff and Typically, the surface layer is very dark grayish brown erosion. gravelly loam about 4 inches thick. The next layer is very Proper stocking rates, pasture rotation, and restricted dark grayish brown clay loam about 15 inches thick. The grazing during wet periods help to keep pastures in good subsoil to a depth of 60 inches is dark brown, brown, and condition and protect the soil from erosion. Grazing when dark yellowish brown clay loam. The depth to bedrock is 60 the soil is wet results in compaction of the surface layer, inches or more. In some areas the surface layer is not poor tilth, and excessive runoff. Periodic mowing and gravelly. clipping help to maintain uniform plant growth, discourage Included in this unit are small areas of Evans, Newberg, selective grazing, and reduce the extent of clumpy growth. and Camas soils on flood plains; Gregory soils on concave Fertilizer is needed to ensure the optimum growth of slopes and near drainageways; Ruch soils on alluvial fans; grasses and, legumes. Grasses respond to nitrogen, and Takilma, Medford, and Central Point soils; and soils that are legumes respond to sulfur and phosphorus. similar to the Foehlin soil but have strata of sand and gravel This unit is well suited to homesite development. The at a depth of more than 40 inches. Also included are small main limitation is the moderately slow permeability. If the areas of Foehlin soils that have slopes of more than 3 soil is used as a site for septic tank absorption fields, the percent. Included areas make up about 20 percent of the moderately slow permeability can be overcome by total acreage. increasing the size of the absorption field. Permeability is moderately slow in the Foehlin soil. Revegetating as soon as possible helps to control Available water capacity is about 10 inches. The effective erosion in disturbed areas around construction sites. rooting depth is 60 inches or more. Runoff is slow, and Topsoil can be stockpiled and used to reclaim areas the hazard of water erosion is slight. disturbed during construction. Because of a low amount of This unit is used mainly for irrigated crops, such as rainfall in summer, irrigation is needed in areas that support alfalfa hay, tree fruit, and small grain. Other crops include lawn grasses, shrubs, vines, shade trees, or ornamental corn for silage and sugar beet seed. Some areas are trees. used for homesite development, grass-legume hay, or The vegetative site is Deep Loamy Terrace, 18- to pasture. 28-inch precipitation zone. 62C-Freezener gravelly loam, 1 to 12 percent slopes. maintain productivity. Compaction can be minimized by This very deep, well drained soil is on plateaus. It formed in using suitable methods of harvesting, laying out skid trails residuum and colluvium derived from andesite. Elevation is in advance, and harvesting timber when the soil is least 1,500 to 4,000 feet. The mean annual precipitation is 30 to susceptible to compaction. Ripping skid trails and landings 50 inches, the mean annual temperature is 45 to 52 when the soil is dry can improve the growth of plants. degrees F, and the average frost-free period is 100 to 160 Erosion can be controlled by carefully planning the days. The native vegetation is mainly conifers and construction and maintenance of logging roads, skid trails, hardwoods and an understory of grasses, shrubs, and forbs. and landings. Seeding, mulching, and benching areas that Typically, the surface is covered with a layer of needles, have been cut and filled also help to control erosion. Skid leaves, and twigs about 1 1/2 inches thick. The surface trails and unsurfaced roads may be impassable during layer is dark reddish brown gravelly loam about 9 inches rainy periods. Logging roads require suitable surfacing for thick. The upper 9 inches of the subsoil is dark reddish year-round use. brown clay loam. The lower 42 inches is dark reddish brown Undesirable plants limit natural or artificial reforestation and dark brown clay and clay loam. The depth to bedrock is unless intensive site preparation and maintenance 60 inches or more. In some areas the surface layer is measures are applied. Reforestation can be accomplished cobbly or stony. by planting Douglas fir and ponderosa pine seedlings. Included in this unit are small areas of Terrabella soils Mulching around seedlings helps to maintain the moisture near drainageways and on concave slopes, Geppert soils supply in summer and minimizes competition from on the more sloping parts of the landscape and on convex undesirable understory plants. slopes, and soils that are similar to the Freezener soil but Severe frost can damage or kill seedlings. Air have more than 35 percent rock fragments or have drainage may be restricted on this unit. Proper timber bedrock within a depth of 60 inches. Also included are harvesting methods can reduce the effect of frost on small areas of Freezener soils that have slopes of more regeneration. than 12 percent. Included areas make up about 15 percent The main limitation affecting livestock grazing is of the total acreage. compaction. The native vegetation suitable for grazing Permeability is moderately slow in the Freezener soil. includes western fescue, mountain brome, tall trisetum, and Available water capacity is about 9 inches. The effective Alaska oniongrass. If the understory is overgrazed, the rooting depth is 60 inches or more. Runoff is stow; and the proportion of preferred forage plants decreases and the hazard of water erosion is slight. proportion of less preferred forage plants increases. This unit is used for timber production, livestock A planned grazing system that includes timely deferment grazing, and wildlife habitat. of grazing, rotation grazing, and proper livestock distribution This unit is suited to the production of Douglas fir. Other helps to prevent overgrazing of the understory and damage species that grow on this unit include sugar pine, to the soil. Grazing should be delayed until the more ponderosa pine, white fir, and California black oak. The desirable forage plants have achieved enough growth to understory vegetation includes Pacific serviceberry, tall withstand grazing pressure and the soil is firm enough to Oregongrape, and western fescue. withstand trampling by livestock. On the basis of a 100-year site curve, the mean site Thinning, logging, and fire reduce the density of the index for Douglas fir is 140. The yield at culmination of the overstory canopy and increase the production of mean annual increment is 8,700 cubic feet per acre in a understory vegetation. Areas that support a large amount fully stocked, even-aged stand of trees at 60 years and of competing vegetation can be improved by prescribed 69,410 board feet per acre (Scribner rule) at 110 years. On burning or by chemical or mechanical treatment. Seeding the basis of a 50-year curve, the mean site index is 105. disturbed areas to suitable plants increases forage The main limitations affecting timber production are production and reduces the risk of erosion. compaction, erosion, and plant competition. Also, the The vegetative site is Mixed Fir-Mixed Pine Forest. bedrock restricts root growth. As a result, windthrow is a hazard. 63E-Freezener gravelly loam, 12 to 35 percent north Conventional methods of harvesting timber generally are slopes. This very deep, well drained soil is on hillslopes. It suitable, but the soil may be compacted if it is moist when formed in colluvium derived from andesite. Elevation is heavy equipment is used. Puddling can occur when the soil 1,500 to 4,000 feet. The mean annual precipitation is 30 to is wet. Using low-pressure ground equipment causes less 50 inches, the mean annual temperature is 45 to 52 damage to the soil and helps to degrees F, and the average frost-free period is 100 to 160 days. The native Properly designed road drainage systems that include vegetation is mainly conifers and hardwoods and an carefully located culverts help to control erosion. Seeding, understory of grasses, shrubs, and forbs. mulching, and benching areas that have been cut and filled Typically, the surface is covered with a layer of needles, also help to control erosion. Steep yarding paths, skid trails, leaves, and twigs about 1 1/2 inches thick. The surface layer and firebreaks are subject to rilling and gullying unless they is dark reddish brown gravelly loam about 9 inches thick. are protected by a plant cover or adequate water bars, or The upper 9 inches of the subsoil is dark reddish brown clay both. Skid trails and unsurfaced roads may be impassable loam. The lower 42 inches is dark reddish brown and dark during rainy periods. Logging roads require suitable brown clay and clay loam. The depth to bedrock is 60 surfacing for year-round use. inches or more. In some areas the surface layer is cobbly or Undesirable plants limit natural or artificial reforestation stony. unless intensive site preparation and maintenance Included in this unit are small areas of Terrabella soils measures are applied. Reforestation can be accomplished near drainageways and on concave slopes, Geppert soils by planting Douglas fir and ponderosa pine seedlings. on the more sloping parts of the landscape and on convex Mulching around seedlings helps to maintain the moisture slopes, and soils that are similar to the Freezener soil but supply in summer and minimizes competition from have more than 35 percent rock fragments or have undesirable understory plants. bedrock within a depth of 60 inches. Also included are The main limitations affecting livestock grazing are small areas of Freezener soils that have slopes of less compaction and erosion. The native vegetation suitable for than 12 or more than 35 percent. Included areas make up grazing includes western fescue, mountain brome, tall about 15 percent of the total acreage. trisetum, and Alaska oniongrass. If the understory is Permeability is moderately slow in the Freezener soil. overgrazed, the proportion of preferred forage plants Available water capacity is about 9 inches. The effective decreases and the proportion of less preferred forage rooting depth is 60 inches or more. Runoff is medium, and plants increases. the hazard of water erosion is moderate. A planned grazing system that includes timely deferment This unit is used for timber production, livestock of grazing, rotation grazing, and proper livestock distribution grazing, and wildlife habitat. helps to prevent overgrazing of the understory and damage This unit is suited to the production of Douglas fir. to the soil. Grazing should be delayed until the more Other species that grow on this unit include white fir, desirable forage plants have achieved enough growth to incense cedar, and Pacific dogwood. The understory withstand grazing pressure and the soil is firm enough to vegetation includes Pacific serviceberry, cascade withstand trampling by livestock. Oregongrape, and deerfoot vanillaleaf. Thinning, logging, and fire reduce the density of the On the basis of a 100-year site curve, the mean site overstory canopy and increase the production of index for Douglas fir is 140. The yield at culmination of the understory vegetation. Areas that support a large amount mean annual increment is 8,700 cubic feet per acre in a of competing vegetation can be improved by prescribed fully stocked, even-aged stand of trees at 60 years and burning or by chemical or mechanical treatment. Seeding 69,410 board feet per acre (Scribner rule) at 110 years. On disturbed areas to suitable plants increases forage the basis of a 50-year curve, the mean site index is 105. production and reduces the risk of erosion. The main limitations affecting timber production are The vegetative site is Mixed Fir-Dogwood Forest. erosion, compaction, and plant competition. Wheeled and tracked logging equipment can be used in the less sloping 64E-Freezener gravelly loam, 12 to 35 percent south areas, but cable yarding generally is safer in the more slopes. This very deep, well drained soil is on hillslopes. It sloping areas and results in less surface disturbance. Using formed in colluvium derived from andesite. Elevation is standard wheeled and tracked equipment when the soil is 1,500 to 4,000 feet. The mean annual precipitation is 30 to moist causes rutting and compaction. Puddling can occur 50 inches, the mean annual temperature is 45 to 52 when the soil is wet. Using low-pressure ground equipment degrees F, and the average frost-free period is 100 to 160 causes less damage to the soil and helps to maintain days. The native vegetation is mainly conifers and productivity. Compaction can be minimized by using suitable hardwoods and an understory of grasses, shrubs, and methods of harvesting, laying out skid trails in advance, and forbs. harvesting timber when the soil is least susceptible to Typically, the surface is covered with a layer of needles; compaction. Ripping skid trails and landings when the soil is leaves, and twigs about 1 1/2 inches thick. The surface dry can improve the growth of plants. layer is dark reddish brown gravelly loam about 9 inches thick. The upper 9 inches of the subsoil is dark and gullying unless they are protected by a plant cover or reddish brown clay loam. The lower 42 inches is dark adequate water bars, or both. Skid trails and unsurfaced reddish brown and dark brown clay and clay loam. The roads may be impassable during rainy periods. Logging depth to bedrock is 60 inches or more. In some areas the roads require suitable surfacing for year-round use. surface layer is cobbly or stony. A high temperature in the surface layer and an Included in this unit are small areas of Terrabella soils insufficient moisture supply in summer increase the near drainageways and on concave slopes, Geppert soils seedling mortality rate. To compensate for the expected on the more sloping parts of the landscape and on convex high mortality rate, the larger seedlings or a greater number slopes, and soils that are similar to the Freezener soil but of seedlings should be planted. When the timber is have more than 35 percent rock fragments or have harvested, leaving some of the larger trees unharvested bedrock within a depth of 60 inches. Also included are provides shade for seedlings. Reforestation can be small areas of Freezener soils that have slopes of less accomplished by planting Douglas fir and ponderosa pine than 12 or more than 35 percent. Included areas make up seedlings. about 15 percent of the total acreage. Undesirable plants limit natural or artificial Permeability is moderately slow in the Freezener soil. reforestation unless intensive site preparation and Available water capacity is about 9 inches. The effective maintenance measures are applied. Mulching around rooting depth is 60 inches or more. Runoff is medium, and seedlings helps to maintain the moisture supply in the hazard of water erosion is moderate. summer and minimizes competition from undesirable This unit is used for timber production, livestock understory plants. grazing, and wildlife habitat. The main limitations affecting livestock grazing are This unit is suited to the production of Douglas fir. Other compaction and erosion. The native vegetation suitable for species that grow on this unit include sugar pine, grazing includes western fescue, mountain brome, tall ponderosa pine, white fir, and California black oak. The trisetum, and Alaska oniongrass. If the understory is understory vegetation includes Pacific serviceberry, tall overgrazed, the proportion of preferred forage plants Oregongrape, and western fescue. decreases and the proportion of less preferred forage plants On the basis of a 100-year site curve, the mean site increases. index for Douglas fir is 125. The yield at culmination of the A planned grazing system that includes timely deferment mean annual increment is 7,320 cubic feet per acre in a of grazing, rotation grazing, and proper livestock distribution fully stocked, even-aged stand of trees at 60 years and helps to prevent overgrazing of the understory and damage 58,200 board feet per acre (Scribner rule) at 120 years. On to the soil. Grazing should be delayed until the soil is firm the basis of a 50-year curve, the mean site index is 90. and the more desirable forage plants have achieved The main limitations affecting timber production are enough growth to withstand grazing pressure. erosion, compaction, seedling mortality, and plant competition. Wheeled and tracked logging equipment can be used in the less sloping areas, but cable yarding Thinning, logging, and fire reduce the density of the generally is safer in the more sloping areas and results in overstory canopy and increase the production of less surface disturbance. Using standard wheeled and understory vegetation. Areas that support a large amount tracked equipment when the soil is moist causes rutting and of competing vegetation can be improved by prescribed compaction. Puddling can occur when the soil is wet. Using burning or by chemical or mechanical treatment. Seeding low-pressure ground equipment causes less damage to the disturbed areas to suitable plants increases forage soil and helps to maintain productivity. Compaction can be production and reduces the risk of minimized by using suitable methods of harvesting, laying erosion. out skid trails in advance, and harvesting timber when the The vegetative site is Mixed Fir-Mixed Pine Forest. soil is least susceptible to compaction. Ripping skid trails and landings when the soil is dry can improve the growth of 65C-Freezener-Geppert complex, 1 to 12 percent plants. slopes. This map unit is on plateaus. Elevation is 1,500 to Properly designed road drainage systems that include 4,000 feet. The mean annual precipitation is 30 to 50 carefully located culverts help to control erosion. Seeding, inches, the mean annual temperature is 45 to 52 degrees F, mulching, and benching areas that have been cut and filled and the average frost-free period is 100 to 160 days. The also help to control erosion. Steep yarding paths, skid trails, native vegetation is mainly conifers and hardwoods and an and firebreaks are subject to rilling understory of grasses, shrubs, and forbs. This unit is about 65 percent Freezener soil and 30 percent Geppert soil. The components of this unit occur as areas so intricately intermingled that mapping them yield at culmination of the mean annual increment is 5,040 separately was not practical at the scale used. cubic feet per acre in a fully stocked, even-aged Included in this unit are small areas of Terrabella soils stand of trees at 60 years and 39,750 board feet per acre near drainageways and on concave slopes and soils that (Scribner rule) at 150 years. On the basis of a 50-year are similar to the Freezener soil but have more than 35 curve, the mean site index is 75. percent rock fragments or have bedrock within a depth of The main limitations affecting timber production are 60 inches. Also included are small areas of Freezener and compaction, erosion, plant competition, and seedling Geppert soils that have slopes of more than 12 percent. mortality. Also, the bedrock underlying the Geppert soil Included areas make up about 5 percent of the total restricts root growth. As a result, windthrow is a hazard. acreage. Conventional methods of harvesting timber generally are The Freezener soil is very deep and well drained. It suitable, but the soils may be compacted if they are moist formed in residuum and colluvium derived dominantly when heavy equipment is used. Puddling can occur when from andesite. Typically, the surface is covered with a the soils are wet. If the soils are excessively disturbed when layer of needles, leaves, and twigs about 1 1/2 inches timber is harvested or logging roads are built, a larger thick. The surface layer is dark reddish brown gravelly number of rock fragments is left on the surface. Using loam about 9 inches thick. The upper 9 inches of the low-pressure ground equipment causes less damage to the subsoil is dark reddish brown clay loam. The lower 42 soils and helps to maintain productivity. Compaction can be inches is dark reddish brown and dark brown clay and minimized by using suitable methods of harvesting, laying clay loam. The depth to bedrock is 60 inches or more. In out skid trails in advance, and harvesting timber when the some areas the surface layer is cobbly or stony. soils are least susceptible to compaction. Ripping skid trails Permeability is moderately slow in the Freezener soil. and landings when the soils are dry can improve the growth Available water capacity is about 9 inches. The effective of plants. rooting depth is 60 inches or more. Runoff is slow, and the Erosion can be controlled by carefully planning the hazard of water erosion is slight. construction and maintenance of logging roads, skid trails, The Geppert soil is moderately deep and well drained. and landings. Seeding, mulching, and benching areas that It formed in colluvium derived dominantly from andesite. have been cut and filled also help to control erosion. Skid Typically, the surface is covered with a layer of needles, trails and unsurfaced roads may be impassable during leaves, and twigs about 1/2 inch thick. The surface layer is rainy periods. Logging roads require suitable surfacing for dark reddish brown very cobbly loam about 13 inches year-round use. thick. The subsoil is dark reddish brown extremely cobbly Undesirable plants limit natural or artificial reforestation clay loam about 17 inches thick. Weathered bedrock is at unless intensive site preparation and maintenance a depth of about 30 inches. The depth to bedrock ranges measures are applied. Reforestation can be accomplished from 20 to 40 inches. In some areas the surface layer is by planting Douglas fir and ponderosa pine seedlings. stony. Mulching around seedlings helps to maintain the moisture Permeability is moderate in the Geppert soil. Available supply in summer and minimizes competition from water capacity is about 3 inches. The effective rooting depth undesirable understory plants. is 20 to 40 inches. Runoff is slow, and the hazard of water A high temperature in the surface layer and an erosion is slight. insufficient moisture supply in summer increase the seedling This unit is used for timber production, livestock mortality rate. The large number of rock fragments in the grazing, and wildlife habitat. Geppert soil also increases the seedling mortality rate. To This unit is suited to the production of Douglas fir. Other compensate for the expected high mortality rate, the larger species that grow on this unit include sugar pine, seedlings or a greater number of seedlings should be ponderosa pine, white fir, and California black oak. The planted. When the timber is harvested, leaving some of the understory vegetation includes Pacific serviceberry, tall larger trees unharvested provides shade for seedlings. Oregongrape, and western fescue. Severe frost can damage or kill seedlings. Air drainage On the basis of a 100-year site curve, the mean site may be restricted on this unit. Proper timber harvesting index for Douglas fir is 140 on the Freezener soil. The yield methods can reduce the effect of frost on regeneration. at culmination of the mean annual increment is 8,700 cubic The main limitation affecting livestock grazing is feet per acre in a fully stocked, even-aged stand of trees at compaction. The native vegetation suitable for grazing 60 years and 69,410 board feet per acre (Scribner rule) at includes western fescue, mountain brome, tall trisetum, and 110 years. On the basis of a 50-year curve, the mean site Alaska oniongrass. If the understory is overgrazed, index is 105. On the basis of a 100-year site curve, the mean site index for Douglas fir is 100 on the Geppert soil. The the proportion of preferred forage plants decreases and the The Geppert soil is moderately deep and well drained. It proportion of less preferred forage plants increases. formed in colluvium derived dominantly from andesite. A planned grazing system that includes timely deferment Typically, the surface is covered with a layer of needles, of grazing, rotation grazing, and proper livestock distribution leaves, and twigs about 1/2 inch thick. The surface layer is helps to prevent overgrazing of the understory and damage dark reddish brown very cobbly loam about 13 inches thick. to the soils. Grazing should be delayed until the more The subsoil is dark reddish brown extremely cobbly clay desirable forage plants have achieved enough growth to loam about 17 inches thick. Weathered bedrock is at a withstand grazing pressure and the soils are firm enough to depth of about 30 inches. The depth to bedrock ranges withstand trampling by livestock. from 20 to 40 inches. In some areas the surface layer is Thinning, logging, and fire reduce the density of the stony. overstory canopy and increase the production of Permeability is moderate in the Geppert soil. Available understory vegetation. Areas that support a large amount water capacity is about 3 inches. The effective rooting depth of competing vegetation can be improved by prescribed is 20 to 40 inches. Runoff is medium, and the hazard of burning or by chemical or mechanical treatment. Seeding water erosion is moderate. disturbed areas to suitable plants increases forage This unit is used for timber production, livestock production and reduces the risk of erosion. grazing, and wildlife habitat. The vegetative site is Mixed Fir-Mixed Pine Forest. This unit is suited to the production of Douglas fir. Other species that grow on this unit include white fir, 66E-Freezener-Geppert complex, 12 to 35 percent incense cedar, and Pacific dogwood. The understory north slopes. This map unit is on hillslopes. Elevation is vegetation includes Pacific serviceberry, cascade 1,500 to 4,000 feet. The mean annual precipitation is 30 to Oregongrape, and deerfoot vanillaleaf. 50 inches, the mean annual temperature is 45 to 52 On the basis of a 100-year site curve, the mean site degrees F, and the average frost-free period is 100 to 160 index for Douglas fir is 140 on the Freezener soil. The yield days. The native vegetation is mainly conifers and at culmination of the mean annual increment is 8,700 cubic hardwoods and an understory of grasses, shrubs, and forbs. feet per acre in a fully stocked, even-aged stand of trees at This unit is about 65 percent Freezener soil and 30 60 years and 69,410 board feet per acre (Scribner rule) at percent Geppert soil. The components of this unit occur as 110 years. On the basis of a 50-year curve, the mean site areas so intricately intermingled that mapping them index is 105. separately was not practical at the scale used. On the basis of a 100-year site curve, the mean site Included in this unit are small areas of Terrabella soils index for Douglas fir is 120 on the Geppert soil. The yield at near drainageways and on concave slopes and soils that culmination of the mean annual increment is 6,900 cubic are similar to the Freezener soil but have more than 35 feet per acre in a fully stocked, even-aged stand of trees at percent rock fragments or have bedrock within a depth of 60 60 years and 52,440 board feet per acre (Scribner rule) at inches. Also included are small areas of Freezener and 120 years. On the basis of a 50-year curve, the mean site Geppert soils that have slopes of less than 12 or more than index is 80. 35 percent. Included areas make up about 5 percent of the The main limitations affecting timber production are total acreage. erosion, compaction, plant competition, and seedling The Freezener soil is very deep and well drained. It mortality. Also, the bedrock underlying the Geppert soil formed in colluvium derived dominantly from andesite. restricts root growth. As a result, windthrow is a hazard. Typically, the surface is covered with a layer of needles, Wheeled and tracked logging equipment can be used in leaves, and twigs about 1 1/2 inches thick. The surface layer the less sloping areas, but cable yarding generally is safer in is dark reddish brown gravelly loam about 9 inches thick. the more sloping areas and results in less surface The upper 9 inches of the subsoil is dark reddish brown clay disturbance. If the soils are excessively disturbed when loam. The lower 42 inches is dark reddish brown and dark timber is harvested or logging roads are built, a larger brown clay and clay loam. The depth to bedrock is 60 number of rock fragments is left on the surface. Using inches or more. In some areas the surface layer is cobbly or standard wheeled and tracked equipment when the soils are stony. moist causes rutting and compaction. Puddling can occur Permeability is moderately slow in the Freezener soil. when the soils are wet. Using low-pressure ground Available water capacity is about 9 inches. The effective equipment causes less damage to the soils and helps to rooting depth is 60 inches or more. Runoff is medium, and maintain productivity. Compaction can be minimized by the hazard of water erosion is moderate. using suitable methods of harvesting, laying out skid trails in advance, and harvesting timber when the soils are least susceptible to compaction. Ripping skid trails and landings 66G-Freezener-Geppert complex, 35 to 60 percent when the soils are dry can improve the growth of plants. north slopes. This map unit is on hillslopes. Elevation is Properly designed road drainage systems that include 1,500 to 4,000 feet. The mean annual precipitation is 30 to carefully located culverts help to control erosion. Seeding, 50 inches, the mean annual temperature is 45 to 52 mulching, and benching areas that have been cut and filled degrees F, and the average frost-free period is 100 to 160 also help to control erosion. Steep yarding paths, skid trails, days. The native vegetation is mainly conifers and and firebreaks are subject to rilling and gullying unless they hardwoods and an understory of grasses, shrubs, and forbs. are protected by a plant cover or adequate water bars, or This unit is about 65 percent Freezener soil and 30 both. Skid trails and unsurfaced roads may be impassable percent Geppert soil. The components of this unit occur as during rainy periods. Logging roads require suitable areas so intricately intermingled that mapping them surfacing for year-round use. separately was not practical at the scale used. Undesirable plants limit natural or artificial reforestation Included in this unit are small areas of McMullin soils and unless intensive site preparation and maintenance Rock outcrop on ridges and convex slopes and soils that measures are applied. Reforestation can be accomplished are similar to the Freezener soil but have more than 35 by planting Douglas fir and ponderosa pine seedlings. percent rock fragments or have bedrock within a depth of Mulching around seedlings helps to maintain the moisture 60 inches. Also included are small areas of Freezener and supply in summer and minimizes competition from Geppert soils that have slopes of less than 35 or more than undesirable understory plants. 60 percent. Included areas make up about 5 percent of the A high temperature in the surface layer and an total acreage. insufficient moisture supply in summer increase the The Freezener soil is very deep and well drained. It seedling mortality rate. The large number of rock fragments formed in colluvium derived dominantly from andesite. in the Geppert soil also increases the seedling mortality Typically, the surface is covered with a layer of needles, rate. To compensate for the expected high mortality rate, leaves, and twigs about 1 1/2 inches thick. The surface the larger seedlings or a greater number of seedlings layer is dark reddish brown gravelly loam about 9 inches should be planted. When the timber is harvested, leaving thick. The upper 9 inches of the subsoil is dark reddish some of the larger trees unharvested provides shade for brown clay loam. The lower 42 inches is dark reddish brown seedlings. and dark brown clay and clay loam. The depth to bedrock is The main limitations affecting livestock grazing are 60 inches or more. In some areas the surface layer is compaction and erosion. The native vegetation suitable for cobbly or stony. grazing includes western fescue, mountain brome, tall Permeability is moderately slow in the Freezener soil. trisetum, and Alaska oniongrass. If the understory is Available water capacity is about 9 inches. The effective overgrazed, the proportion of preferred forage plants rooting depth is 60 inches or more. Runoff is rapid, and the decreases and the proportion of less preferred forage plants hazard of water erosion is high. increases. The Geppert soil is moderately deep and well drained. It A planned grazing system that includes timely deferment formed in colluvium derived dominantly from andesite. of grazing, rotation grazing, and proper livestock distribution Typically, the surface is covered with a layer of needles, helps to prevent overgrazing of the understory and damage leaves, and twigs about 1/2 inch thick. The surface layer is to the soils. Grazing should be delayed until the more dark reddish brown very cobbly loam about 13 inches desirable forage plants have achieved enough growth to thick. The subsoil is dark reddish brown extremely cobbly withstand grazing pressure and the soils are firm enough to clay loam about 17 inches thick. Weathered bedrock is at a withstand trampling by livestock. depth of about 30 inches. The depth to bedrock ranges Thinning, logging, and fire reduce the density of the from 20 to 40 inches. In some areas the surface layer is overstory canopy and increase the production of stony. understory vegetation. Areas that support a large amount Permeability is moderate in the Geppert soil. Available of competing vegetation can be improved by prescribed water capacity is about 3 inches. The effective rooting depth burning or by chemical or mechanical treatment. Seeding is 20 to 40 inches. Runoff is rapid, and the hazard of water disturbed areas to suitable plants increases forage erosion is high. production and reduces the risk of erosion. This unit is used for timber production, livestock The vegetative site is Mixed Fir-Dogwood Forest. grazing, and wildlife habitat. This unit is suited to the production of Douglas fir. Other species that grow on this unit include white fir, incense cedar, and Pacific dogwood. The understory vegetation includes Pacific serviceberry, cascade Oregongrape, and deerfoot vanillaleaf. may be impassable during rainy periods. Logging roads On the basis of a 100-year site curve, the mean site require suitable surfacing for year-round use. index for Douglas fir is 140 on the Freezener soil. The yield Undesirable plants limit natural or artificial reforestation at culmination of the mean annual increment is 8,700 cubic unless intensive site preparation and maintenance feet per acre in a fully stocked, even-aged stand of trees at measures are applied. Reforestation can be accomplished 60 years and 69,410 board feet per acre (Scribner rule) at by planting Douglas fir and ponderosa pine seedlings. 110 years. On the basis of a 50-year curve, the mean site Mulching around seedlings helps to maintain the moisture index is 105. supply in summer and minimizes competition from On the basis of a 100-year site curve, the mean site undesirable understory plants. index for Douglas fir is 120 on the Geppert soil. The yield A high temperature in the surface layer and an at culmination of the mean annual increment is 6,900 cubic insufficient moisture supply in summer increase the feet per acre in a fully stocked, even-aged stand of trees at seedling mortality rate. The large number of rock fragments 60 years and 52,440 board feet per acre (Scribner rule) at in the Geppert soil also increases the seedling mortality 120 years. On the basis of a 50-year curve, the mean site rate. To compensate for the expected high mortality rate, index is 80. the larger seedlings or a greater number of seedlings The main limitations affecting timber production are the should be planted. When the timber is harvested, leaving slope, erosion, compaction, plant competition, and seedling some of the larger trees unharvested provides .shade for mortality. Also, the bedrock underlying the Geppert soil seedlings. restricts root growth. As a result, windthrow is a hazard. The main limitations affecting livestock grazing are Wheeled and tracked logging equipment can be used in erosion, compaction, and the slope. The native vegetation the less sloping areas, but cable yarding generally is safer suitable for grazing includes western fescue, mountain and results in less surface disturbance. If the soils are brome, tall trisetum, and Alaska oniongrass. If the excessively disturbed when timber is harvested or logging understory is overgrazed, the proportion of preferred forage roads are built, a larger number of rock fragments is left on plants decreases and the proportion of less preferred forage the surface. Using standard wheeled and tracked equipment plants increases. when the soils are moist causes rutting and compaction. A planned grazing system that includes timely deferment Puddling can occur when the soils are wet. Using of grazing, rotation grazing, and proper livestock distribution low-pressure ground equipment causes less damage to the helps to prevent overgrazing of the understory and damage soils and helps to maintain productivity. Compaction can be to the soils. Grazing should be delayed until the more minimized by using suitable methods of harvesting, laying desirable forage plants have achieved enough growth to out skid trails in advance, and harvesting timber when the withstand grazing pressure and the soils are firm enough to soils are least susceptible to compaction. Ripping skid trails withstand trampling by livestock. and landings when the soils are dry can improve the growth Thinning, logging, and fire reduce the density of the of plants. overstory canopy and increase the production of Properly designed road drainage systems that include understory vegetation. Areas that support a large amount carefully located culverts help to control erosion. Seeding, of competing vegetation can be improved by prescribed mulching, and benching areas that have been cut and filled burning or by chemical or mechanical treatment. Seeding also help to control erosion. Steep yarding paths, skid trails, disturbed areas to suitable plants increases forage and firebreaks are subject to rilling and gullying unless they production and reduces the risk of erosion. are protected by a plant cover or adequate water bars, or The vegetative site is Mixed Fir-Dogwood Forest. both. Cutbanks occasionally slump when the soils are saturated. 67E-Freezener-Geppert complex, 12 to 35 percent Constructing logging roads on the steeper slopes can south slopes. This map unit is on hillslopes. Elevation is result in a high risk of erosion. Building the roads at 1,500 to 4,000 feet. The mean annual precipitation is 30 to midslope requires extensive cutting and filling and removes 50 inches, the mean annual temperature is 45 to 52 land from production. Material that is discarded when the degrees F, and the average frost-free period is 100 to 160 roads are built can damage vegetation and is a potential days. The native vegetation is mainly conifers and source of sedimentation. If the material becomes saturated, hardwoods and an understory of grasses, shrubs, and forbs. avalanches of debris can occur. End hauling of the waste This unit is about 65 percent Freezener soil and 30 material minimizes damage to the vegetation downslope percent Geppert soil. The components of this unit occur as and reduces the risk of sedimentation. Skid trails and areas so intricately intermingled that mapping them unsurfaced roads separately was not practical at the scale used. cubic feet per acre in a fully stocked, even-aged stand of Included in this unit are small areas of Terrabella soils trees at 60 years and 37,120 board feet per acre (Scribner near drainageways and on concave slopes and soils that are rule) at 160 years. On the basis of a 50-year curve, the similar to the Freezener soil but have more than 35 percent mean site index is 70. rock fragments or have bedrock within a depth of 60 inches. The main limitations affecting timber production are Also included are small areas of Freezener and Geppert erosion, compaction, seedling mortality, and plant soils that have slopes of less than 12 or more than 35 competition. Also, the bedrock underlying the Geppert soil percent. Included areas make up about 5 percent of the total restricts root growth. As a result, windthrow is a hazard. acreage. Wheeled and tracked logging equipment can be used in The Freezener soil is very deep and well drained. It the less sloping areas, but cable yarding generally is safer in formed in colluvium derived dominantly from andesite. the more sloping areas and results in less surface Typically, the surface is covered with a layer of needles, disturbance. If the soils are excessively disturbed when leaves, and twigs about 1 1/2 inches thick. The surface layer timber is harvested or logging roads are built, a larger is dark reddish brown gravelly loam about 9 inches thick. number of rock fragments is left on the surface. Using The upper 9 inches of the subsoil is dark reddish brown clay standard wheeled and tracked equipment when the soils are loam. The lower 42 inches is dark reddish brown and dark moist causes rutting and compaction. Puddling can occur brown clay and clay loam. The depth to bedrock is 60 inches when the soils are wet. Using low-pressure ground or more. In some areas the surface layer is cobbly or stony. equipment causes less damage to the soils and helps to Permeability is moderately slow in the Freezener soil. maintain productivity. Compaction can be minimized by using Available water capacity is about 9 inches. The effective suitable methods of harvesting, laying out skid trails in rooting depth is 60 inches or more. Runoff is medium, and advance, and harvesting timber when the soils are least the hazard of water erosion is moderate. susceptible to compaction. Ripping skid trails and landings The Geppert soil is moderately deep and well drained. It when the soils are dry can improve the growth of plants. formed in colluvium derived dominantly from andesite. Properly designed road drainage systems that include Typically, the surface is covered with a layer of needles, carefully located culverts help to control erosion. Seeding, leaves, and twigs about 1/2 inch thick. The surface layer is mulching, and benching areas that have been cut and filled; dark reddish brown very cobbly loam about 13 inches thick. also help to control erosion. Steep yarding paths, skid trails, The subsoil is dark reddish brown extremely cobbly clay and firebreaks are subject to rilling and gullying unless they loam about 17 inches thick. Weathered bedrock is at a are protected by a plant cover or adequate water bars, or depth of about 30 inches. The depth to bedrock ranges both. Skid trails and unsurfaced roads may be impassable from 20 to 40 inches. In some areas the surface layer is during rainy periods. Logging roads require suitable stony. surfacing for year-round use. Permeability is moderate in the Geppert soil. Available A high temperature in the surface layer and an insufficient water capacity is about 3 inches. The effective rooting depth moisture supply in summer increase the seedling mortality is 20 to 40 inches. Runoff is medium, and the hazard of rate. The large number of rock fragments in the Geppert soil water erosion is moderate. also increases the seedling mortality rate. To compensate This unit is used for timber production, livestock for the expected high mortality rate, the larger seedlings or a grazing, and wildlife habitat. greater number of seedlings should be planted. When the This unit is suited to the production of Douglas fir and timber is harvested, leaving some of the larger trees ponderosa pine. Other species that grow on this unit unharvested provides shade for seedlings. Reforestation can include sugar pine, white fir, and California black oak. be accomplished by planting Douglas fir and ponderosa pine The understory vegetation includes Pacific serviceberry, seedlings. tall Oregongrape, and western fescue. Undesirable plants limit natural or artificial On the basis of a 100-year site curve, the mean site reforestation unless intensive site preparation and index for Douglas fir is 125 on the Freezener soil. The yield maintenance measures are applied. Mulching around at culmination of the mean annual increment is 7,320 cubic seedlings helps to maintain the moisture supply in feet per acre in a fully stocked, even-aged stand of trees at summer and minimizes competition from undesirable 60 years and 58,200 board feet per acre (Scribner rule) at understory plants. 120 years. On the basis of a 50year curve, the mean site The main limitations affecting livestock grazing are index is 90. On the basis of a 100-year site curve, the mean site index for Douglas fir is 95 on the Geppert soil. The yield at culmination of the mean annual increment is 4,620 compaction and erosion. The native vegetation suitable for Permeability is moderately slow in the Freezener soil. grazing includes western fescue, mountain brome, tall Available water capacity is about 9 inches. The effective trisetum, and Alaska oniongrass. If the understory is rooting depth is 60 inches or more. Runoff is rapid, and the overgrazed, the proportion of preferred forage plants hazard of water erosion is high. decreases and the proportion of less preferred forage The Geppert soil is moderately deep and well drained. It plants increases. formed in colluvium derived dominantly from andesite. A planned grazing system that includes timely deferment Typically, the surface is covered with a layer of needles, of grazing, rotation grazing, and proper livestock distribution leaves, and twigs about 1/2 inch thick. The surface layer is helps to prevent overgrazing of the understory and damage dark reddish brown very cobbly loam about 13 inches to the soils. Grazing should be delayed until the more thick. The subsoil is dark reddish brown extremely cobbly desirable forage plants have achieved enough growth to clay loam about 17 inches thick. Weathered bedrock is at a withstand grazing pressure and the soils are firm enough to depth of about 30 inches. The depth to bedrock ranges withstand trampling by livestock. from 20 to 40 inches. In some areas the surface layer is Thinning, logging, and fire reduce the density of the stony. overstory canopy and increase the production of Permeability is moderate in the Geppert soil. Available understory vegetation. Areas that support a large amount water capacity is about 3 inches. The effective rooting depth of competing vegetation can be improved by prescribed is 20 to 40 inches. Runoff is rapid, and the hazard of water burning or by chemical or mechanical treatment. Seeding erosion is high. disturbed areas to suitable plants increases forage This unit is used for timber production, livestock production and reduces the risk of erosion. grazing, and wildlife habitat. The vegetative site is Mixed Fir-Mixed Pine Forest. This unit is suited to the production of Douglas fir and ponderosa pine. Other species that grow on this unit 67G-Freezener-Geppert complex, 35 to 60 percent include sugar pine, white fir, and California black oak. south slopes. This map unit is on hillslopes. Elevation is The understory vegetation includes Pacific serviceberry, 1,500 to 4,000 feet. The mean annual precipitation is 30 to tall Oregongrape, and western fescue. 50 inches, the mean annual temperature is 45 to 52 degrees On the basis of a 100-year site curve, the mean site F, and the average frost-free period is 100 to 160 days. The index for Douglas fir is 125 on the Freezener soil. The yield native vegetation is mainly conifers and hardwoods and an at culmination of the mean annual increment is 7,320 cubic understory of grasses, shrubs, and forbs. feet per acre in a fully stocked, even-aged stand of trees at This unit is about 65 percent Freezener soil and 30 60 years and 58,200 board feet per acre (Scribner rule) at percent Geppert soil. The components of this unit occur as 120 years. On the basis of a 50-year curve, the mean site areas so intricately intermingled that mapping them index is 90. separately was not practical at the scale used. On the basis of a 100-year site curve, the mean site Included in this unit are small areas of McMullin soils and index for Douglas fir is 95 on the Geppert soil. The yield at Rock outcrop on ridges and convex slopes and soils that culmination of the mean annual increment is 4,620 cubic are similar to the Freezener soil but have more than 35 feet per acre in a fully stocked, even-aged stand of trees at percent rock fragments or have bedrock within a depth of 60 years and 37,120 board feet per acre (Scribner rule) at 60 inches. Also included are small areas of Freezener and 160 years. On the basis of a 50-year curve, the mean site Geppert soils that have slopes of less than 35 or more than index is 70. 60 percent. Included areas make up about 5 percent of the The main limitations affecting timber production are the total acreage. slope, erosion, compaction, seedling mortality, and plant The Freezener soil is very deep and well drained. It competition. Also, the bedrock underlying the Geppert soil formed in colluvium derived dominantly from andesite. restricts root growth. As a result, windthrow is a hazard. Typically, the surface is covered with a layer of needles, Wheeled and tracked logging equipment can be used in leaves, and twigs about 1 1/2 inches thick. The surface layer the less sloping areas, but cable yarding generally is safer is dark reddish brown gravelly loam about 9 inches thick. and results in less surface disturbance. If the soils are The upper 9 inches of the subsoil is dark reddish brown clay excessively disturbed when timber is harvested or logging loam. The lower 42 inches is dark reddish brown and dark roads are built, a larger number of rock fragments is left on brown clay and clay loam. The depth to bedrock is 60 the surface. Using standard wheeled and tracked equipment inches or more. In some areas the surface layer is cobbly or when the soils are moist causes rutting and compaction. stony. Puddling can occur when the soils are wet. Using low-pressure ground equipment causes less damage to the soils and helps to maintain productivity. Compaction can be understory and damage to the soils. Grazing should be minimized by using suitable methods of harvesting, laying delayed until the more desirable forage plants have out skid trails in advance, and harvesting timber when the achieved enough growth to withstand grazing pressure and soils are least susceptible to compaction. Ripping skid the soils are firm enough to withstand trampling by trails and landings when the soils are dry can improve the livestock. growth of plants. Thinning, logging, and fire reduce the density of the Properly designed road drainage systems that include overstory canopy and increase the production of carefully located culverts help to control erosion. Seeding, understory vegetation. Areas that support a large amount mulching, and benching areas that have been cut and filled of competing vegetation can be improved by prescribed also help to control erosion. Steep yarding paths, skid trails, burning or by chemical or mechanical treatment. Seeding and firebreaks are subject to rilling and gullying unless they disturbed areas to suitable plants increases forage are protected by a plant cover or adequate water bars, or production and reduces the risk of erosion. both. Cutbanks occasionally slump when the soils are The vegetative site is Mixed Fir-Mixed Pine Forest. saturated. Constructing logging roads on the steeper slopes can 68C-Geppert very cobbly loam, 1 to 12 percent result in a high risk of erosion. Building the roads at slopes. This moderately deep, well drained soil is on midslope requires extensive cutting and filling and removes plateaus. It formed in colluvium derived from andesite. land from production. Material that is discarded when the Elevation is 1,500 to 4,000 feet. The mean annual roads are built can damage vegetation and is a potential precipitation is 30 to 50 inches, the mean annual source of sedimentation. If the material becomes saturated, temperature is 45 to 52 degrees F, and the average avalanches of debris can occur. End hauling of the waste frost-free period is 100 to 160 days. The native vegetation material minimizes damage to the vegetation downslope is mainly conifers and hardwoods and an understory of and reduces the risk of sedimentation. Skid trails and grasses, shrubs, and forbs. unsurfaced roads may be impassable during rainy periods. Typically, the surface is covered with a layer of Logging roads require suitable surfacing for year-round use. needles, leaves, and twigs about 1/2 inch thick. The A high temperature in the surface layer and an surface layer is dark reddish brown very cobbly loam insufficient moisture supply in summer increase the about 13 inches thick. The subsoil is dark reddish brown seedling mortality rate. The large number of rock fragments extremely cobbly clay loam about 17 inches thick. in the Geppert soil also increases the seedling mortality Weathered bedrock is at a depth of about 30 inches. The rate. To compensate for the expected high mortality rate, depth to bedrock ranges from 20 to 40 inches. In some the larger seedlings or a greater number of seedlings areas the surface layer is stony. should be planted. When the timber is harvested, leaving Included in this unit are small areas of Terrabella soils some of the larger trees unharvested provides shade for near drainageways and on concave slopes, Freezener soils seedlings. The seedling mortality rate also can be reduced on concave slopes, Rock outcrop on convex slopes, and by providing artificial shade for seedlings. Reforestation can soils that are similar to the Geppert soil but have bedrock at be accomplished by planting Douglas fir and ponderosa a depth of more than 40 inches. Also included are small pine seedlings. areas of Geppert soils that have slopes of more than 12 Undesirable plants limit natural or artificial percent. Included areas make up about 15 percent of the reforestation unless intensive site preparation and total acreage. maintenance measures are applied. Mulching around Permeability is moderate in the Geppert soil. Available seedlings helps to maintain the moisture supply in water capacity is about 3 inches. The effective rooting depth summer and minimizes competition from undesirable is 20 to 40 inches. Runoff is slow, and the hazard of water understory plants. erosion is slight. The main limitations affecting livestock grazing are This unit is used for timber production, livestock erosion, compaction, and the slope. The native vegetation grazing, and wildlife habitat. suitable for grazing includes western fescue, mountain This unit is suited to the production of Douglas fir. Other brome, tall trisetum, and Alaska oniongrass. If the species that grow on this unit include sugar pine, understory is overgrazed, the proportion of preferred forage ponderosa pine, white fir, and California black oak. The plants decreases and the proportion of less preferred forage understory vegetation includes Pacific serviceberry, tall plants increases. Oregongrape, and western fescue. A planned grazing system that includes timely deferment On the basis of a 100-year site curve, the mean site of grazing, rotation grazing, and proper livestock distribution index for Douglas fir is 100. The yield at culmination of the helps to prevent overgrazing of the mean annual increment is 5,040 cubic feet per acre in a fully stocked, even-aged stand of trees at 60 years and A planned grazing system that includes timely deferment 39,750 board feet per acre (Scribner rule) at 150 years. On of grazing, rotation grazing, and proper livestock distribution the basis of a 50-year curve, the mean site index is 75. helps to prevent overgrazing of the understory and damage The main limitations affecting timber production are to the soil. Grazing should be delayed until the more compaction, erosion, plant competition, and seedling desirable forage plants have achieved enough growth to mortality. Also, the bedrock restricts root growth. As a withstand grazing pressure and the soil is firm enough to result, windthrow is a hazard. withstand trampling by livestock. Conventional methods of harvesting timber generally are Thinning, logging, and fire reduce the density of the suitable, but the soil may be compacted if it is moist when overstory canopy and increase the production of heavy equipment is used. Puddling can occur when the soil understory vegetation. Areas that support a large amount is wet. If the soil is excessively disturbed when timber is of competing vegetation can be improved by prescribed harvested or logging roads are built, a larger number of rock burning or by chemical or mechanical treatment. Seeding fragments is left on the surface. Using low-pressure ground disturbed areas to suitable plants increases forage equipment causes less damage to the soil and helps to production and reduces the risk of erosion. maintain productivity. Compaction can be minimized by The vegetative site is Mixed Fir-Mixed Pine Forest. using suitable methods of harvesting, laying out skid trails in advance, and harvesting timber when the soil is least 69E-Geppert very cobbly loam, 12 to 35 percent north susceptible to compaction. Ripping skid trails and landings slopes. This moderately deep, well drained soil is on when the soil is dry can improve the growth of plants. hillslopes. It formed in colluvium derived from andesite. Erosion can be controlled by carefully planning the Elevation is 1,500 to 4,000 feet. The mean annual construction and maintenance of logging roads, skid trails, precipitation is 30 to 50 inches, the mean annual and landings. Seeding, mulching, and benching areas that temperature is 45 to 52 degrees F, and the average have been cut and filled also help to control erosion. Skid frost-free period is 100 to 160 days. The native vegetation is trails and unsurfaced roads may be impassable during mainly conifers and hardwoods and an understory of rainy periods. Logging roads require suitable surfacing for grasses, shrubs, and forbs. year-round use. Typically, the surface is covered with a layer of Undesirable plants limit natural or artificial reforestation needles, leaves, and twigs about 1/2 inch thick. The unless intensive site preparation and maintenance surface layer is dark reddish brown very cobbly loam measures are applied. Reforestation can be accomplished about 13 inches thick. The subsoil is dark reddish brown by planting Douglas fir and ponderosa pine seedlings. extremely cobbly clay loam about 17 inches thick. Mulching around seedlings helps to maintain the moisture Weathered bedrock is at a depth of about 30 inches. The supply in summer and minimizes competition from depth to bedrock ranges from 20 to 40 inches. In some undesirable understory plants. areas the surface layer is stony. A high temperature in the surface layer during summer Included in this unit are small areas of Terrabella soils and the low available water capacity increase the seedling near drainageways and on concave slopes, Freezener mortality rate. The large number of rock fragments in the soils on concave slopes, Rock outcrop on ridges and soil also increases the seedling mortality rate. To convex slopes, and soils that are similar to the Geppert compensate for the expected high mortality rate, the larger soil but have bedrock at a depth of more than 40 inches. seedlings or a greater number of seedlings should be Also included are small areas of Geppert soils that have planted. When the timber is harvested, leaving some of the slopes of less than 12 or more than 35 percent. Included larger trees unharvested provides shade for seedlings. areas make up about 15 percent of the total acreage. Severe frost can damage or kill seedlings. Air Permeability is moderate in the Geppert soil. Available drainage may be restricted on this unit. Proper timber water capacity is about 3 inches. The effective rooting depth harvesting methods can reduce the effect of frost on is 20 to 40 inches. Runoff is medium, and the hazard of regeneration. water erosion is moderate. The main limitation affecting livestock grazing is This unit is used for timber production, livestock compaction. The native vegetation suitable for grazing grazing, and wildlife habitat. includes western fescue, mountain brome, tall trisetum, and This unit is suited to the production of Douglas fir. Alaska oniongrass. If the understory is overgrazed, the Other species that grow on this unit include white fir, proportion of preferred forage plants decreases and the incense cedar, and Pacific dogwood. The understory proportion of less preferred forage plants increases. vegetation includes Pacific serviceberry, cascade Oregongrape, and deerfoot vanillaleaf. The main limitations affecting livestock grazing are On the basis of a 100-year site curve, the mean site compaction and erosion. The native vegetation suitable for index for Douglas fir is 120. The yield at culmination of the grazing includes western fescue, mountain brome, tall mean annual increment is 6,900 cubic feet per acre in a trisetum, and Alaska oniongrass. If the understory is fully stocked, even-aged stand of trees at 60 years and overgrazed, the proportion of preferred forage plants 52,440 board feet per acre (Scribner rule) at 120 years. On decreases and the proportion of less preferred forage plants the basis of a 50-year curve, the mean site index is 80. increases. The main limitations affecting timber production are A planned grazing system that includes timely deferment erosion, compaction, plant competition, and seedling of grazing, rotation grazing, and proper livestock distribution mortality. Also, the bedrock restricts root growth. As a helps to prevent overgrazing of the understory and damage result, windthrow is a hazard. to the soil. Grazing should be delayed until the more Wheeled and tracked logging equipment can be used in desirable forage plants have achieved enough growth to the less sloping areas, but cable yarding generally is safer withstand grazing pressure and the soil is firm enough to in the more sloping areas and results in less surface withstand trampling by livestock. disturbance. If the soil is excessively disturbed when timber Thinning, logging, and fire reduce the density of the is harvested or logging roads are built, a larger number of overstory canopy and increase the production of rock fragments is left on the surface. Using standard understory vegetation. Areas that support a large amount wheeled and tracked equipment when the soil is moist of competing vegetation can be improved by prescribed causes rutting and compaction. Puddling can occur when burning or by chemical or mechanical treatment. Seeding the soil is wet. Using low-pressure ground equipment disturbed areas to suitable plants increases forage causes less damage to the soil and helps to maintain production and reduces the risk of erosion. productivity. Compaction can be minimized by using The vegetative site is Mixed Fir-Dogwood Forest. suitable methods of harvesting, laying out skid trails in advance, and harvesting timber when the soil is least 69G-Geppert very cobbly loam, 35 to 70 percent north susceptible to compaction. Ripping skid trails and landings slopes. This moderately deep, well drained soil is on when the soil is dry can improve the growth of plants. hillslopes. It formed in colluvium derived from andesite. Properly designed road drainage systems that include Elevation is 1,500 to 4,000 feet. The mean annual carefully located culverts help to control erosion. Seeding, precipitation, is 30 to 50 inches, the mean annual mulching, and benching areas that have been cut and filled temperature is 45 to 52 degrees F, and the average also help to control erosion. Steep yarding paths, skid trails, frost-free period is 100 to 160 days. The native vegetation is and firebreaks are subject to rilling and gullying unless they mainly conifers and hardwoods and an understory of are protected by a plant cover or adequate water bars, or grasses, shrubs, and forbs. both. Skid trails and unsurfaced roads may be impassable Typically, the surface is covered with a layer of during rainy periods. Logging roads require suitable needles, leaves, and twigs about 1/2 inch thick. The surfacing for year-round use. surface layer is dark reddish brown very cobbly loam Undesirable plants limit natural or artificial reforestation about 13 inches thick. The subsoil is dark reddish brown unless intensive site preparation and maintenance extremely cobbly clay loam about 17 inches thick. measures are applied. Reforestation can be accomplished Weathered bedrock is at a depth of about 30 inches. by planting Douglas fir and ponderosa pine seedlings. The depth to bedrock ranges from 20 to 40 inches. In Mulching around seedlings helps to maintain the moisture some areas the surface layer is stony. supply in summer and minimizes competition from Included in this unit are small areas of Freezener soils undesirable understory plants. on the less sloping parts of the landscape, Rock outcrop on A high temperature in the surface layer during summer ridges and convex slopes, and soils that are similar to the and the low available water capacity increase the seedling Geppert soil but have bedrock at a depth of more than 40 mortality rate. The large number of rock fragments in the inches. Also included are small areas of Geppert soils that soil also increases the seedling mortality rate. To have slopes of less than 35 or more than 70 percent. compensate for the expected high mortality rate, the larger Included areas make up about 10 percent of the total seedlings or a greater number of seedlings should be acreage. planted. When the timber is harvested, leaving some of the Permeability is moderate in the Geppert soil. Available larger trees unharvested provides shade for seedlings. water capacity is about 3 inches. The effective rooting depth is 20 to 40 inches. Runoff is rapid, and the hazard of water erosion is high. This unit is used for timber production, livestock Undesirable plants limit natural or artificial reforestation grazing, and wildlife habitat. unless intensive site preparation and maintenance This unit is suited to the production of Douglas fir. measures are applied. Reforestation can be accomplished Other species that grow on this unit include white fir, by planting Douglas fir and ponderosa pine seedlings. incense cedar, and Pacific dogwood. The understory Mulching around seedlings helps to maintain the moisture vegetation includes Pacific serviceberry, cascade supply in summer and minimizes competition from Oregongrape, and deerfoot vanillaleaf. undesirable understory plants. On the basis of a 100-year site curve, the mean site A high temperature in the surface layer during summer index for Douglas fir is 120. The yield at culmination of the and the low available water capacity increase the seedling mean annual increment is 6,900 cubic feet per acre in a mortality rate. The large number of rock fragments in the fully stocked, even-aged stand of trees at 60 years and soil also increases the seedling mortality rate. To 52,440 board feet per acre (Scribner rule) at 120 years. On compensate for the expected high mortality rate, the larger the basis of a 50-year curve, the mean site index is 80. seedlings or a greater number of seedlings should be The main limitations affecting timber production are the planted. When the timber is harvested, leaving some of the slope, erosion, compaction, plant competition,, and larger trees unharvested provides shade for seedlings. seedling mortality. Also, the bedrock restricts root growth. The main limitations affecting livestock grazing are As a result, windthrow is a hazard. erosion, compaction, and the slope. The native vegetation Wheeled and tracked logging equipment can be used in suitable for grazing includes western fescue, mountain the less sloping areas, but cable yarding generally is safer brome, tall trisetum, and Alaska oniongrass. If the and results in less surface disturbance. If the soil is understory is overgrazed, the proportion of preferred forage excessively disturbed when timber is harvested or logging plants decreases and the proportion of less preferred forage roads are built, a larger number of rock fragments is left on plants increases. the surface. Using standard wheeled and tracked A planned grazing system that includes timely deferment equipment when the soil is moist causes rutting and of grazing, rotation grazing, and proper livestock distribution compaction. Puddling can occur when the soil is wet. Using helps to prevent overgrazing of the understory and damage low-pressure ground equipment causes less damage to the to the soil. Grazing should be delayed until the more soil and helps to maintain productivity. Compaction can be desirable forage plants have achieved enough growth to minimized by using suitable methods of harvesting, laying withstand grazing pressure and the soil is firm enough to out skid trails in advance, and harvesting timber when the withstand trampling by livestock. soil is least susceptible to compaction. Ripping skid trails Thinning, logging, and fire reduce the density of the and landings when the soil is dry can improve the growth of overstory canopy and increase the production of plants. understory vegetation. Areas that support a large amount Properly designed road drainage systems that include of competing vegetation can be improved by prescribed carefully located culverts help to control erosion. Seeding, burning or by chemical or mechanical treatment. Seeding mulching, and benching areas that have been cut and filled disturbed areas to suitable plants increases forage also help to control erosion. Steep yarding paths, skid trails, production and reduces the risk of erosion. and firebreaks are subject to rilling and gullying unless they The vegetative site is Mixed Fir-Dogwood Forest. are protected by a plant cover or adequate water bars, or both. Cutbanks occasionally slump when the soil is 70E-Geppert very cobbly loam, 12 to 35 percent south saturated. slopes. This moderately deep, well drained soil is on Constructing logging roads on the steeper slopes can hillslopes. It formed in colluvium derived from andesite. result in a high risk of erosion. Building the roads at Elevation is 1,500 to 4,000 feet. The mean annual midslope requires extensive cutting and filling and removes precipitation is 30 to 50 inches, the mean annual land from production. Material that is discarded. when the temperature is 45. to 52 degrees F, and the average roads are built can damage vegetation and is a potential frost-free period is 100 to 160 days. The native vegetation is source of sedimentation. If the material becomes saturated, mainly conifers and hardwoods and an understory of avalanches of debris can occur. End hauling of the waste grasses, shrubs, and forbs. material minimizes damage to the vegetation downslope Typically, the surface is covered with a layer of and reduces the risk of sedimentation. Skid trails and needles, leaves, and twigs about 1/2 inch thick. The unsurfaced roads may be impassable during rainy periods. surface layer is dark reddish brown very cobbly loam Logging roads require suitable surfacing for year-round use. about 13 inches thick. The subsoil is dark reddish brown extremely cobbly clay loam about 17 inches cut and filled also help to control erosion. Steep yarding thick. Weathered bedrock is at a depth of about 30 paths, skid trails, and firebreaks are subject to rilling and inches. The depth to bedrock ranges from 20 to 40 gullying unless they are protected by a plant cover. or inches. In some areas the surface layer is stony. adequate water bars, or both. Skid trails and unsurfaced Included in this unit are small areas of Terrabella soils roads may be impassable during rainy periods. Logging near drainageways and on concave slopes, Freezener roads require suitable surfacing for year-round use. soils on concave slopes, Rock outcrop on ridges and A high temperature in the surface layer during summer convex slopes, and soils that are similar to the Geppert and the low available water capacity increase the seedling soil but have bedrock at a depth of more than 40 inches. mortality rate. The large number of rock fragments in the Also included are small areas of Geppert soils that have soil also increases the seedling mortality rate. To slopes of less than 12 or more than 35 percent. Included compensate for the expected high mortality rate, the larger areas make up about 15 percent of the total acreage. seedlings or a greater number of seedlings should be Permeability is moderate in the Geppert soil. Available planted. When the timber is harvested, leaving some of the water capacity is about 3 inches. The effective rooting depth larger trees unharvested provides shade for seedlings. is 20 to 40 inches. Runoff is medium, and the hazard of Reforestation can be accomplished by planting Douglas fir water erosion is moderate. and ponderosa pine seedlings. This unit is used for timber production, livestock Undesirable plants limit natural or artificial grazing, and wildlife habitat. reforestation unless intensive site preparation and This unit is suited to the production of Douglas fir and maintenance measures are applied. Mulching around ponderosa pine. Other species that grow on this unit seedlings helps to maintain the moisture supply in include sugar pine, white fir, and California black oak. summer and minimizes competition from undesirable The understory vegetation includes Pacific serviceberry, understory plants. tall Oregongrape, and western fescue. The main limitations affecting livestock grazing are On the basis of a 100-year site curve, the mean site compaction and erosion. The native vegetation suitable for index for Douglas fir is 95. The yield at culmination of the grazing includes western fescue, mountain brome, tall mean annual increment is 4,620 cubic feet per acre in a trisetum, and Alaska oniongrass. If the understory is fully stocked, even-aged stand of trees at 60 years and overgrazed, the proportion of preferred forage plants 37,120 board feet per acre (Scribner rule) at 160 years. On decreases and the proportion of less preferred forage plants the basis of a 50-year curve, the mean site index is 70. increases. The main limitations affecting timber production are A planned grazing system that includes timely deferment erosion, compaction, seedling mortality, and plant of grazing, rotation grazing, and proper livestock distribution competition. Also, the bedrock restricts root growth. As a helps to prevent overgrazing of the understory and damage result, windthrow is a hazard. to the soil. Grazing should be delayed until the more Wheeled and tracked logging equipment can be used in desirable forage plants have achieved enough growth to the less sloping areas, but cable yarding generally is safer withstand grazing pressure . and the soil is firm enough to in the more sloping areas and results in less surface withstand trampling by livestock. disturbance. If the soil is excessively disturbed when timber Thinning, logging, and fire reduce the density of the is harvested or logging roads are built, a larger number of overstory canopy and increase the production of rock fragments is left on the surface. Using standard understory vegetation. Areas that support a large amount wheeled and tracked equipment when the soil is moist of competing vegetation can be improved by prescribed causes rutting and compaction. Puddling can occur when burning or by chemical or mechanical treatment. Seeding the soil is wet. Using low-pressure ground equipment disturbed areas to suitable plants increases forage causes less damage to the soil and helps to maintain production and reduces the risk of erosion. productivity. Compaction can be minimized by using The vegetative site is Mixed Fir-Mixed Pine Forest. suitable methods of harvesting, laying out skid trails in advance, and harvesting timber when the soil is least 70G-Geppert very cobbly loam, 35 to 60 percent susceptible to compaction. Ripping skid trails and landings south slopes. This moderately deep, well drained soil is on when the soil is dry can improve the growth of plants. hillslopes. It formed in colluvium derived from andesite. Properly designed road drainage systems that include Elevation is 1,500 to 4,000 feet. The mean annual carefully located culverts help to control erosion. Seeding, precipitation is 30 to 50 inches, the mean annual mulching, and benching areas that have been temperature is 45 to 52 degrees F, and the average using suitable methods of harvesting, laying out skid trails frost-free period is 100 to 160 days. The native in advance, and harvesting timber when the soil is least vegetation is mainly conifers and hardwoods and an susceptible to compaction. Ripping skid trails and landings understory of grasses, shrubs, and forbs. when the soil is dry can improve the growth of plants. Typically, the surface is covered with a layer of Properly designed road drainage systems that include needles, leaves, and twigs about 1/2 inch thick. The carefully located culverts help to control erosion. Seeding, surface layer is dark reddish brown very cobbly loam mulching, and benching areas that have been cut and filled about 13 inches thick. The subsoil is dark reddish brown also help to control erosion. Steep yarding paths, skid trails, extremely cobbly clay loam about 17 inches thick. and firebreaks are subject to rilling and gullying unless they Weathered bedrock is at a depth of about 30 inches. are protected by a plant cover or adequate water bars, or The depth to bedrock ranges from 20 to 40 inches. In both. Cutbanks occasionally slump when the soil is some areas the surface layer is stony. saturated. Included in this unit are small areas of Freezener soils Constructing logging roads on the steeper slopes can on the less sloping parts of the landscape, Rock outcrop on result in a high risk of erosion. Building the roads at ridges and convex slopes, and soils that are similar to the midslope requires extensive cutting and filling and removes Geppert soil but have bedrock at a depth of more than 40 land from production. Material that is discarded when the inches. Also included are small areas of Geppert soils that roads are built can damage vegetation and is a potential have slopes of less than 35 or more than 60 percent. source of sedimentation. If the material becomes saturated, Included areas make up about 10 percent of the total avalanches of debris can occur. End hauling of the waste acreage. material minimizes damage to the vegetation downslope Permeability is moderate in the Geppert soil. Available and reduces the risk of sedimentation. Skid trails and water capacity is about 3 inches. The effective rooting depth unsurfaced roads may be impassable during rainy periods. is 20 to 40 inches. Runoff is rapid, and the hazard of water Logging roads require suitable surfacing for year-round use. erosion is high. A high temperature in the surface layer during summer This unit is used for timber production, livestock and the low available water capacity increase the seedling grazing, and wildlife habitat. mortality rate. The large number of rock fragments in the This unit is suited to the production of Douglas fir and soil also increases the seedling mortality rate. To ponderosa pine. Other species that grow on this unit compensate for the expected high mortality rate, the larger include sugar pine, white fir, and California black oak. seedlings or a greater number of seedlings should be The understory vegetation includes Pacific serviceberry, planted. When the timber is harvested, leaving some of the tall Oregongrape, and western fescue. larger trees unharvested provides shade for seedlings. The On the basis of a 100-year site curve, the mean site seedling mortality rate also can be reduced by providing index for Douglas fir is 95. The yield at culmination of the artificial shade for seedlings. Reforestation can be mean annual increment is 4,620 cubic feet per acre in a accomplished by planting Douglas fir and ponderosa pine fully stocked, even-aged stand of trees at 60 years and seedlings. 37,120 board feet per acre (Scribner rule) at 160 years. On Undesirable plants limit natural or artificial the basis of a 50-year curve, the mean site index is 70. reforestation unless intensive site preparation and The main limitations affecting timber production are the maintenance measures are applied. Mulching around slope, erosion, compaction, seedling mortality, and plant seedlings helps to maintain the moisture supply in competition. Also, the bedrock restricts root growth. As a summer and minimizes competition from undesirable result, windthrow is a hazard. understory plants. Wheeled and tracked logging equipment can be used in The main limitations affecting livestock grazing are the less sloping areas, but cable yarding generally is safer erosion, compaction, and the slope. The native vegetation and results in less surface disturbance. If the soil is suitable for grazing includes western fescue, mountain excessively disturbed when timber is harvested or logging brome, tall trisetum, and Alaska oniongrass, If the roads are built, a larger number of rock fragments is left on understory is overgrazed, the proportion of preferred forage the surface. Using standard wheeled and tracked equipment plants decreases and the proportion of less preferred forage when the soil is moist causes rutting and compaction. plants increases. Puddling can occur when the soil is wet. Using low-pressure A planned grazing system that includes timely deferment ground equipment causes less damage to the soil and helps of grazing, rotation grazing, and proper livestock distribution to maintain productivity. Compaction can be minimized by helps to prevent overgrazing of the understory and damage to the soil. Grazing should be On the basis of a 100-year site curve, the mean site delayed until the more desirable forage plants have index for Douglas fir is 125. The yield at culmination of the achieved enough growth to withstand grazing pressure mean annual increment is 7,320 cubic feet per acre in a and the soil is firm enough to withstand trampling by fully stocked, even-aged stand of trees at 60 years and livestock. 58,200 board feet per acre (Scribner rule) at 120 years. On Thinning, logging, and fire reduce the density of the the basis of a 50-year curve, the mean site index is 95. overstory canopy and increase the production of The main limitations affecting timber production are understory vegetation. Areas that support a large amount erosion, compaction, slumping, and plant competition. of competing vegetation can be improved by prescribed Also, the bedrock restricts root growth. As a result, burning or by chemical or mechanical treatment. Seeding windthrow is a hazard. disturbed areas to suitable plants increases forage When timber is harvested, management that minimizes production and reduces the risk of erosion. the risk of erosion is essential. Wheeled and tracked logging The vegetative site is Mixed Fir-Mixed Pine Forest. equipment can be used in the less sloping areas, but cable yarding generally is safer in the more sloping areas and 71E-Goolaway silt loam, 20 to 35 percent north results in less surface disturbance. Using standard wheeled slopes. This moderately deep, well drained soil is on and tracked equipment when the soil is moist causes rutting hillslopes. It formed in colluvium derived dominantly from and compaction. Puddling can occur when the soil is wet. schist. Elevation is 1,500 to 4,000 feet. The mean annual Using low-pressure ground equipment causes less damage precipitation is 40 to 50 inches, the mean annual to the soil and helps to maintain productivity. Compaction temperature is 45 to 52 degrees F, and the average can be minimized by using suitable methods of harvesting, frost-free period is 100 to 160 days. The native vegetation is laying out skid trails in advance, and harvesting timber when mainly conifers and hardwoods and an understory of the soil is least susceptible to compaction. Ripping skid trails grasses, shrubs, and forbs. and landings when the soil is dry can improve the growth of Typically, the surface is covered with a layer of needles, plants. leaves, and twigs about 2 inches thick. The surface layer is Properly designed road drainage systems that include very dark grayish brown silt loam about 3 inches thick. The carefully located culverts help to control erosion. Areas that next layer is dark grayish brown silt loam about 8 inches have been cut and filled are easily eroded unless they are thick. The subsoil is olive gray and olive silt loam about 18 treated. Seeding, mulching, and benching these areas help inches thick. Weathered bedrock is at a depth of about 29 to control erosion. Steep yarding paths, skid trails, and inches. The depth to bedrock ranges from 20 to 40 inches. firebreaks are subject to rilling and gullying unless they are Included in this unit are small areas of Josephine, protected by a plant cover or adequate water bars, or both. Siskiyou, and Speaker soils; Musty soils on ridges and This unit is subject to slumping. Road failure and convex slopes; Pollard soils on the less sloping parts of the landslides are likely to occur after road construction and landscape and on concave slopes; poorly drained soils clearcutting. Slumping can be minimized by constructing near drainageways and on concave slopes; and soils that logging roads in the less sloping areas, on better suited soils are similar to the Goolaway soil but have bedrock at a if practical, and by installing properly designed road depth of more than 40 inches. Also included are small drainage systems. Skid trails and unsurfaced roads may be areas of Goolaway soils that have slopes of less than 20 or impassable during rainy periods. Logging roads require more than 35 percent. Included areas make up about 20 suitable surfacing for year-round use. percent of the total acreage. Undesirable plants limit natural or artificial reforestation Permeability is moderate in the Goolaway soil. Available unless intensive site preparation and maintenance water capacity is about 6 inches. The effective rooting depth measures are applied. Reforestation can be accomplished is 20 to 40 inches. Runoff is medium, and the hazard of by planting Douglas fir seedlings. Mulching around water erosion is moderate or high. seedlings helps to maintain the moisture supply in This unit is used for timber production and wildlife summer and minimizes competition from undesirable habitat. It is suited to the production of Douglas fir. Other understory plants. species that grow on this unit include ponderosa pine, Increased erosion, loss of plant nutrients, and water incense cedar, and sugar pine. The understory vegetation repellency are likely to result from fires of moderate includes golden chinkapin, cascade Oregongrape, and intensity. deerfoot vanillaleaf. The vegetative site is Douglas Fir-Chinkapin Forest. 71F-Goolaway silt loam, 35 to 50 percent north when the soil is wet. Using low-pressure ground equipment slopes. This moderately deep, well drained soil is on causes less damage to the soil and helps to maintain hillslopes. It formed in colluvium derived dominantly from productivity. Compaction can be minimized by using schist. Elevation is 1,500 to 4,000 feet. The mean annual suitable methods of harvesting, laying out skid trails in precipitation is 40 to 50 inches, the mean annual advance, and harvesting timber when the soil is least temperature is 45 to 52 degrees F, and the average susceptible to compaction. Ripping skid trails and landings frost-free period is 100 to 160 days. The native vegetation is when the soil is dry can improve the growth of plants. mainly conifers and hardwoods and an understory of Properly designed road drainage systems that include grasses, shrubs, and forbs. carefully located culverts help to control erosion Areas that Typically, the surface is covered with a layer of needles, have been cut and filled are easily eroded unless they are leaves, and twigs about 2 inches thick. The surface layer is treated: Seeding, mulching, and benching these areas help very dark grayish brown silt loam about 3 inches thick. The to control erosion. Steep yarding paths, skid trails, and next layer is dark grayish brown silt loam about 8 inches firebreaks are subject to rilling and gullying unless they are thick. The subsoil is olive gray and olive silt loam about 18 protected by a plant cover or adequate water bars, or both. inches thick. Weathered bedrock is at a depth of about 29 Constructing logging roads on the steeper slopes can inches. The depth to bedrock ranges from 20 to 40 inches. result in a high risk of erosion. Material that is discarded Included iii this unit are small areas of Josephine, when the roads are built can damage vegetation and is a Siskiyou, and Speaker soils; Musty soils on ridges and potential source of sedimentation. If the material becomes convex slopes; Pollard soils on the less sloping parts of the saturated, avalanches of debris can occur. End hauling of landscape and on concave slopes; and soils that are similar the waste material minimizes damage to the vegetation to the Goolaway soil but have bedrock at a depth of more downslope and reduces the risk of sedimentation. than 40 inches. Also included are small areas of Goolaway This unit is subject to slumping. Road failure and soils that have slopes of less than 35 or more than 50 landslides are likely to occur after road construction and percent. Included areas make up about 20 percent of the clearcutting. Slumping can be minimized by constructing total acreage. logging roads in the less sloping areas, on better suited soils Permeability is moderate in the Goolaway soil. Available if practical, and by installing properly designed road water capacity is about 6 inches. The effective rooting depth drainage systems. Skid trails and unsurfaced roads may be is 20 to 40 inches. Runoff is rapid, and the hazard of water impassable during rainy periods. Logging roads require erosion is high. suitable surfacing for year-round use. This unit is used for timber production and wildlife Undesirable plants limit natural or artificial reforestation habitat. It is suited to the production of Douglas fir. Other unless intensive site preparation and maintenance species that grow on this unit include ponderosa pine, measures are applied. Reforestation can be accomplished incense cedar, and sugar pine. The understory vegetation by planting Douglas fir seedlings. Mulching around includes golden chinkapin, cascade Oregongrape, and seedlings helps to maintain the moisture supply in deerfoot vanillaleaf. summer and minimizes competition from undesirable On the basis of a 100-year site curve, the mean site understory plants. index for Douglas fir is 125. The yield at culmination of the Increased erosion, loss of plant nutrients, and water mean annual increment is 7,320 cubic feet per acre in a repellency are likely to result from fires of moderate fully stocked, even-aged stand of trees at 60 years and intensity. 58,200 board feet per acre (Scribner rule) at 120 years. On The vegetative site is Douglas Fir-Chinkapin Forest. the basis of a 50-year curve, the mean site index is 95. The main limitations affecting timber production are the 72E-Goolaway silt loam, 20 to 35 percent south slope, erosion, compaction, slumping, and plant slopes. This moderately deep, well drained soil is on competition. Also, the bedrock restricts root growth. As a hillslopes. It formed in colluvium derived dominantly from result, windthrow is a hazard. schist. Elevation is 1,500 to 4,000 feet. The mean annual When timber is harvested, management that minimizes precipitation is 40 to 50 inches, the mean annual the risk of erosion is essential. Wheeled and tracked temperature is 45 to 52 degrees F, and the average logging equipment can be used in the less sloping areas, frost-free period is 100 to 160 days. The native vegetation is but cable yarding generally is safer and results in less mainly conifers and hardwoods and an understory of surface disturbance. Using standard wheeled and tracked grasses, shrubs, and forbs. equipment when the soil is moist causes rutting and Typically, the surface is covered with a layer of compaction. Puddling can occur needles, leaves, and twigs about 2 inches thick. The Properly designed road drainage systems that include surface layer is very dark grayish brown silt loam about 3 carefully located culverts help to control erosion. Areas that inches thick. The next layer is dark grayish brown silt loam have been cut and filled are easily eroded unless they are about 8 inches thick. The subsoil is olive gray and olive silt treated. Seeding, mulching, and benching these areas help loam about 18 inches thick. Weathered bedrock is at a to control erosion. Steep yarding paths, skid trails, and depth of about 29 inches. The depth to bedrock ranges firebreaks are subject to rilling and gullying unless they are from 20 to 40 inches. protected by a plant cover or adequate water bars, or both. Included in this unit are small areas of Josephine, This unit is subject to slumping. Road failure and Siskiyou, and Speaker soils; Musty soils on ridges and landslides are likely to occur after road construction and convex slopes; Pollard soils on the less sloping parts of the clearcutting. Slumping can be minimized by constructing landscape and on concave slopes; poorly drained soils logging roads in the less sloping areas, on better suited soils near drainageways and on concave slopes; and soils that if practical, and by installing properly designed road are similar to the Goolaway soil but have bedrock at a drainage systems. Skid trails and unsurfaced roads may be depth of more than 40 inches. Also included are small impassable during rainy periods. Logging roads require areas of Goolaway soils that have slopes of less than 20 or suitable surfacing for year-round use. more than 35 percent. Included areas make up about 20 A high temperature in the surface layer and an percent of the total acreage. insufficient moisture supply in summer increase the seedling Permeability is moderate in the Goolaway soil. Available mortality rate. To compensate for the expected high water capacity is about 6 inches. The effective rooting depth mortality rate, the larger seedlings or a greater number of is 20 to 40 inches. Runoff is medium, and the hazard of seedlings should be planted. When the timber is harvested, water erosion is moderate or high. leaving some of the larger trees unharvested provides This unit is used for timber production and wildlife shade for seedlings. Reforestation can be accomplished by habitat. It is suited to the production of Douglas fir. Other planting Douglas fir and ponderosa pine seedlings. species that grow on this unit include ponderosa pine, Undesirable plants limit natural or artificial sugar pine, and California black oak. The understory reforestation unless intensive site preparation and vegetation includes canyon live oak, deerbrush, and maintenance measures are applied. Mulching around western fescue. seedlings helps to maintain the moisture supply in On the basis of a 100-year site curve, the mean site summer and minimizes competition from undesirable index for Douglas fir is 115. The yield at culmination of the understory plants. mean annual increment is 6,360 cubic feet per acre in a Increased erosion, loss of plant nutrients, and water fully stocked, even-aged stand of trees at 60 years and repellency are likely to result from fires of moderate 50,700 board feet per acre (Scribner rule) at 130 years. On intensity. the basis of a 50-year curve, the mean site index is 90. The vegetative site is Douglas Fir-Black Oak Forest. The main limitations affecting timber production are erosion, compaction, slumping, seedling mortality, and 72F-Goolaway silt loam, 35 to 50 percent south plant competition. Also, the bedrock restricts root growth. slopes. This moderately deep, well drained soil is on As a result, windthrow is a hazard. hillslopes. It formed in colluvium derived dominantly from When timber is harvested, management that minimizes schist. Elevation is 1,500 to 4,000 feet. The mean annual the risk of erosion is essential. Wheeled and tracked logging precipitation is 40 to 50 inches, the mean annual equipment can be used in the less sloping areas, but cable temperature is 45 to 52 degrees F, and the average yarding generally is safer in the more sloping areas and frost-free period is 100 to 160 days. The native vegetation is results in less surface disturbance. Using standard wheeled mainly conifers and hardwoods and an understory of and tracked equipment when the soil is moist causes rutting grasses, shrubs, and forbs. and compaction. Puddling can occur when the soil is wet. Typically, the surface is covered with a layer of needles, Using low-pressure ground equipment causes less damage leaves, and twigs about 2 inches thick. The surface layer is to the soil and helps to maintain productivity. Compaction very dark grayish brown silt loam about 3 inches thick. The can be minimized by using suitable methods of harvesting, next layer is dark grayish brown silt loam about 8 inches laying out skid trails in advance, and harvesting timber when thick. The subsoil is olive gray and olive silt loam about 18 the soil is least susceptible to compaction. Ripping skid inches thick. Weathered bedrock is at a depth of about 29 trails and landings when the soil is dry can improve the inches. The depth to bedrock ranges from 20 to 40 inches. growth of plants. Included in this unit are small areas of Josephine, Siskiyou, and Speaker soils; Musty soils on ridges and when the roads are built can damage vegetation and is a convex slopes; Pollard soils on the less sloping parts of the potential source of sedimentation. If the material becomes landscape and on concave slopes; and soils that are similar saturated, avalanches of debris can occur. End hauling of to the Goolaway soil but have bedrock at a depth of more the waste material minimizes damage to the vegetation than 40 inches. Also included are small areas of Goolaway downslope and reduces the risk of sedimentation. soils that have slopes of less than 35 or more than 50 This unit is subject to slumping. Road failure and percent. Included areas make up about 20 percent of the landslides are likely to occur after road construction and total acreage. clearcutting. Slumping can be minimized by constructing Permeability is moderate in the Goolaway soil. Available logging roads in the less sloping areas, on better suited soils water capacity is about 6 inches. The effective rooting depth if practical, and by installing properly designed road is 20 to 40 inches. Runoff is rapid, and the hazard of water drainage systems. Skid trails and unsurfaced roads may be erosion is high. impassable during rainy periods. Logging roads require This unit is used for timber production and wildlife suitable surfacing for year-round use. habitat. It is suited to the production of Douglas fir. Other A high temperature in the surface layer and an species that grow on this unit include ponderosa pine, insufficient moisture supply in summer increase the seedling sugar pine, and California black oak. The understory mortality rate. To compensate for the expected high vegetation includes canyon live oak, deerbrush, and mortality rate, the larger seedlings or a greater number of western fescue. seedlings should be planted. When the timber is harvested, On the basis of a 100-year site curve, the mean site leaving some of the larger trees unharvested provides index for Douglas fir is 115. The yield at culmination of the shade for seedlings. The seedling mortality rate also can be mean annual increment is 6,360 cubic feet per acre in a reduced by providing artificial shade for seedlings. fully stocked, even-aged stand of trees at 60 years and Reforestation can be accomplished by planting Douglas fir 50,700 board feet per acre (Scribner rule) at 130 years. On and ponderosa pine seedlings. the basis of a 50-year curve, the mean site index is 90. Undesirable plants limit natural or artificial The main limitations affecting timber production are the reforestation unless intensive site preparation and slope, erosion, compaction, slumping, seedling mortality, maintenance measures are applied. Mulching around and plant competition. Also, the bedrock restricts root seedlings helps to maintain the moisture supply in growth. As a result, windthrow is a hazard. summer and minimizes competition from undesirable When timber is harvested, management that minimizes understory plants. the risk of erosion is essential. Wheeled and tracked Increased erosion, loss of plant nutrients, and water logging equipment can be used in the less sloping areas, repellency are likely to result from fires of moderate but cable yarding generally is safer and results in less intensity. surface disturbance. Using standard wheeled and tracked The vegetative site is Douglas Fir-Black Oak Forest. equipment when the soil is moist causes rutting and compaction. Puddling can occur when the soil is wet. Using 73E-Goolaway-Pollard complex, 7 to 30 percent low-pressure ground equipment causes less damage to the slopes. This map unit is on hillslopes and alluvial fans. soil and helps to maintain productivity. Compaction can be Elevation is 1,500 to 4,000 feet. The mean annual minimized by using suitable methods of harvesting, laying precipitation is 40 to 50 inches, the mean annual out skid trails in advance, and harvesting timber when the temperature is 45 to 52 degrees F, and the average soil is least susceptible to compaction. Ripping skid trails frost-free period is 100 to 160 days. The native vegetation and landings when the soil is dry can improve the growth of is mainly conifers and hardwoods and an understory of plants. grasses, shrubs, and forbs. Properly designed road drainage systems that include This unit is about 55 percent Goolaway soil and 25 carefully located culverts help to control erosion. Areas that percent Pollard soil. The Goolaway soil has slopes of more have been cut and filled are easily eroded unless they are than 12 percent. The components of this unit occur as treated. Seeding, mulching, and benching these areas help areas so intricately intermingled that mapping them to control erosion. Steep yarding paths, skid trails, and separately was not practical at the scale used. firebreaks are subject to rilling and gullying unless they are Included in this unit are small areas of Josephine, protected by a plant cover or adequate water bars, or both. Speaker, and Wolfpeak soils; poorly drained soils near Constructing logging roads on the steeper slopes can drainageways and on concave slopes; soils that are similar result in a high risk of erosion. Material that is discarded to the Goolaway soil but have bedrock at a depth of more than 40 inches; and Goolaway soils that have slopes of more than 30 percent. Also included are small areas of Pollard soils that have slopes of less Goolaway soil restricts root growth. As a result, than 7 percent. Included areas make up about 20 windthrow is a hazard. percent of the total acreage. When timber is harvested, management that minimizes The Goolaway soil is moderately deep and well drained. the risk of erosion is essential. Wheeled and tracked logging It formed in colluvium derived dominantly from schist. equipment can be used in the less sloping areas, but cable Typically, the surface is covered with a layer of needles, yarding generally is safer in the more sloping areas and leaves, and twigs about 2 inches thick. The surface layer is results in less surface disturbance. Using standard wheeled very dark grayish brown silt loam about 3 inches thick. The and tracked equipment when the soils are moist causes next layer is dark grayish brown silt loam about 8 inches rutting and compaction. Puddling can occur when the soils thick. The subsoil is olive gray and olive silt loam about 18 are wet. Using low-pressure ground equipment causes less inches thick. Weathered bedrock is at a depth of about 29 damage to the soils and helps to maintain productivity. inches. The depth to bedrock ranges from 20 to 40 inches. Compaction can be minimized by using suitable methods of Permeability is moderate in the Goolaway soil. Available harvesting, laying out skid trails in advance, and harvesting water capacity is about 6 inches. The effective rooting depth timber when the soils are least susceptible to compaction. is 20 to 40 inches. Runoff is medium, and the hazard of Ripping skid trails and landings when the soils are dry can water erosion is moderate or high. improve the growth of plants. The Pollard soil is very deep and well drained. It formed Properly designed road drainage systems that include in alluvium and colluvium derived dominantly from carefully located culverts help to control erosion. Areas that metamorphic rock. Typically, the surface is covered with a have been cut and filled are easily eroded unless they are layer of needles, leaves, and twigs about 2 inches thick. The treated. Seeding, mulching, and benching these areas help surface layer is dark brown loam about 11 inches thick. The to control erosion. Steep yarding paths, skid trails, and upper 25 inches of the subsoil is dark reddish brown clay firebreaks are subject to rilling and gullying unless they are loam. The lower 25 inches is yellowish red and brown clay protected by a plant cover or adequate water bars, or both. loam. The depth to bedrock is 60 inches or more. In some Skid trails and unsurfaced roads may be impassable during areas the surface layer is clay loam or gravelly loam. rainy periods. Logging roads require suitable surfacing for Permeability is slow in the Pollard soil. Available water year-round use. capacity is about 7 inches. The effective rooting depth is This unit is subject to slumping. Road failure and 60 inches or more. Runoff is medium, and the hazard of landslides are likely to occur after road construction and water erosion is moderate. clearcutting. Slumping can be minimized by constructing This unit is used for timber production and wildlife logging roads in the less sloping areas, on better suited soils habitat. It is suited to the production of Douglas fir. Other if practical, and by installing properly designed road species that grow on this unit include ponderosa pine, drainage systems. incense cedar and sugar pine. The understory vegetation Undesirable plants limit natural or artificial reforestation includes golden chinkapin, cascade Oregongrape, and unless intensive site preparation and maintenance deerfoot vanillaleaf. measures are applied. Reforestation can be accomplished On the basis of a 100-year site curve, the mean site by planting Douglas fir seedlings. Mulching around index for Douglas fir is 125 on the Goolaway soil. The yield seedlings helps to maintain the moisture supply in at culmination of the mean annual increment is 7,320 cubic summer and minimizes competition from undesirable feet per acre in a fully stocked, even-aged stand of trees at understory plants. 60 years and 58,200 board feet per acre (Scribner rule) at A high temperature in the surface layer and an 120 years. On the basis of a 50-year curve, the mean site insufficient moisture supply in summer increase the seedling index is 95. mortality rate, especially on south- and southwest-facing On the basis of a 100-year site curve, the mean site slopes. To compensate for the expected high mortality rate, index for Douglas fir is 130 on the Pollard soil. The yield at the larger seedlings or a greater number of seedlings should culmination of the mean annual increment is 7,740 cubic be planted. When the timber is harvested, leaving some of feet per acre in a fully stocked, even-aged stand of trees at the larger trees unharvested provides shade for seedlings. 60 years and 58,520 board feet per acre (Scribner rule) at Increased erosion, loss of plant nutrients, and water 110 years. On the basis of a 50-year curve, the mean site repellency are likely to result from fires of moderate index is 95. intensity. The main limitations affecting timber production are The vegetative site is Douglas Fir-Chinkapin Forest. erosion, compaction, slumping, plant competition, and seedling mortality. Also, the bedrock underlying the 74F-Gravecreek gravelly loam, 35 to 55 percent north is excessively disturbed when timber is harvested or logging slopes. This moderately deep, well drained soil is on roads are built, a larger number of rock fragments is left on hillslopes. It formed in colluvium derived from serpentinitic the surface. Using standard wheeled and tracked rock. Elevation is 2,200 to 4,300 feet. The mean annual equipment when the soil is moist causes rutting and precipitation is 45 to 55 inches, the mean annual compaction. Puddling can occur when the soil is wet. Using temperature is 45 to 50 degrees F, and the average low-pressure ground equipment causes less damage to the frost-free period is 100 to 160 days. The native vegetation is soil and helps to maintain productivity. Compaction can be mainly conifers and hardwoods and an understory of minimized by using suitable methods of harvesting, laying grasses, shrubs, and forbs. out skid trails in advance, and harvesting timber when the Typically, the surface is covered with a layer of needles, soil is least susceptible to compaction. Ripping skid trails leaves, and twigs about 1 inch thick. The surface layer is and landings when the soil is dry can improve the growth of very dark grayish brown and dark brown gravelly loam about plants. 7 inches thick. The upper 8 inches of the subsoil is brown Properly designed road drainage systems that include very gravelly clay loam. The lower 14 inches is light olive carefully located culverts help to control erosion. Seeding, brown very cobbly clay loam. Bedrock is at a depth of about mulching, and benching areas that have been cut and filled 29 inches. The depth to bedrock ranges from 20 to 40 also help to control erosion. Steep yarding paths, skid trails, inches. In some areas the surface layer is very cobbly or and firebreaks are subject to rilling and gullying unless they stony. are protected by a plant cover or adequate water bars, or Included in this unit are small areas of Acker, Dubakella, both. Cutbanks occasionally slump when the soil is and Norling soils; Rock outcrop and Pearsoll soils on ridges saturated. and convex slopes; Dumont soils on concave slopes and on Constructing logging roads on the steeper slopes can the less sloping parts of the landscape; and, on concave result in a high risk of erosion. Material that is discarded slopes and foot slopes, soils that are similar to the when the roads are built can damage vegetation and is a Gravecreek soil but have bedrock at a depth of more than potential source of sedimentation. If the material becomes 40 inches. Also included are small areas of Gravecreek saturated, avalanches of debris can occur. End hauling of soils that have slopes of less than 35 or more than 55 the waste material minimizes damage to the vegetation percent. Included areas make up about 20 percent of the downslope and reduces the risk of sedimentation. Skid trails total acreage. and unsurfaced roads may be impassable during rainy Permeability is moderately slow in the Gravecreek periods. Logging roads require suitable surfacing for soil. Available water capacity is about 3 inches. The year-round use. effective rooting depth is 20 to 40 inches. Runoff is A high content of magnesium and low content of calcium rapid, and the hazard of water erosion is high. increase the seedling mortality rate. The large number of This unit is used for timber production and wildlife rock fragments in the soil also increases the seedling habitat. It is suited to the production of Douglas fir. Other mortality rate. To compensate for the expected high species that grow on this unit include incense cedar, mortality rate, the larger seedlings or a greater number of Jeffrey pine, sugar pine, and Pacific madrone. The seedlings should be planted. Reforestation can be understory vegetation includes cascade Oregongrape, accomplished by planting Jeffrey pine, ponderosa pine, and common beargrass, and creambush oceanspray. Douglas fir seedlings. On the basis of a 100-year site curve, the mean site Undesirable plants limit natural or artificial index for Douglas fir is 95. The yield at culmination of the reforestation unless intensive site preparation and mean annual increment is 4,620 cubic feet per acre in a maintenance measures are applied. Mulching around fully stocked, even-aged stand of trees at 60 years and seedlings helps to maintain the moisture supply in 37,120 board feet per acre (Scribner rule) at 160 years. On summer and minimizes competition from undesirable the basis of a 50-year curve, the mean site index is 70. understory plants. The main limitations affecting timber production are the The vegetative site is Douglas Fir-Beargrass Forest, slope, erosion, compaction, seedling mortality, and plant Serpentine. competition. Also, the bedrock restricts root growth. As a result, windthrow is a hazard. 74G-Gravecreek gravelly loam, 55 to 80 percent north Wheeled and tracked logging equipment can be used in slopes. This moderately deep, well drained soil is on the less sloping areas, but cable yarding generally is safer hillslopes. It formed in colluvium derived from serpentinitic and results in less surface disturbance. If the soil rock. Elevation is 2,200 to 4,300 feet. The mean annual precipitation is 45 to 55 inches, the mean annual temperature is 45 to 50 degrees F, and the average frost-free period is 100 to 160 days. The native the bedrock is highly fractured or where rock layers are vegetation is mainly conifers and hardwoods and an parallel to the slopes (fig. 8). Steep yarding paths and understory of grasses, shrubs, and forbs. firebreaks are subject to rilling and gullying unless they are Typically, the surface is covered with a layer of needles, protected by a plant cover or adequate water bars, or both. leaves, and twigs about 1 inch thick. The surface layer is Building logging roads at midslope requires extensive very dark grayish brown and dark brown gravelly loam about cutting and filling and removes land from production. 7 inches thick. The upper 8 inches of the subsoil is brown Material that is discarded when the roads are built can very gravelly clay loam. The lower 14 inches is light olive damage vegetation and is a potential source of brown very cobbly clay loam. Bedrock is at a depth of about sedimentation. If the material becomes saturated, 29 inches. The depth to bedrock ranges from 20 to 40 avalanches of debris can occur. End hauling of the waste inches. In some areas the surface layer is very cobbly or material minimizes damage to the vegetation downslope stony. and reduces the risk of sedimentation. Unsurfaced roads Included in this unit are small areas of Acker, Dubakella, may be impassable during rainy periods. Logging roads and Norling soils; Rock outcrop and Pearsoll soils on ridges require suitable surfacing for year-round use. and convex slopes; and soils that are similar to the A high content of magnesium and low content of calcium Gravecreek soil but have bedrock at a depth of more than increase the seedling mortality rate. The large number of 40 inches. Also included are small areas of Gravecreek rock fragments in the soil also increases the seedling soils that have slopes of less than 55 or more than 80 mortality rate. To compensate for the expected high percent. Included areas make up about 20 percent of the mortality rate, the larger seedlings or a greater number of total acreage. seedlings should be planted. Reforestation can be Permeability is moderately slow in the Gravecreek accomplished by planting Jeffrey pine, ponderosa pine, and soil. Available water capacity is about 3 inches. The Douglas fir seedlings. effective rooting depth is 20 to 40 inches. Runoff is Undesirable plants limit natural or artificial rapid, and the hazard of water erosion is high. reforestation unless intensive site preparation and This unit is used for timber production and wildlife maintenance measures are applied. Mulching around habitat. It is suited to the production of Douglas fir. Other seedlings helps to maintain the moisture supply in species that grow on this unit include incense cedar, summer and minimizes competition from undesirable Jeffrey pine, sugar pine, and Pacific madrone. The understory plants. understory vegetation includes cascade Oregongrape, The vegetative site is Douglas Fir-Beargrass Forest, common beargrass, and creambush oceanspray. Serpentine. On the basis of a 100-year site curve, the mean site index for Douglas fir is 95. The yield at culmination of the 75E-Gravecreek cobbly loam, 12 to 35 percent mean annual increment is 4,620 cubic feet per acre in a south slopes. This moderately deep, well drained soil is fully stocked, even-aged stand of trees at 60 years and on hillslopes and ridges. It formed in colluvium derived 37,120 board feet per acre (Scribner rule) at 160 years. On from serpentinitic rock. Elevation is 2,200 to 4,300 feet. the basis of a 50-year curve, the mean site index is 70. The mean annual precipitation is 45 to 55 inches, the The main limitations affecting timber production are the mean annual temperature is 45 to 50 degrees F, and the slope, erosion, seedling mortality, and plant competition. average frost-free period is 100 to 160 days. The native Also, the bedrock restricts root growth. As a result, vegetation is mainly conifers and hardwoods and an windthrow is a hazard. understory of grasses, shrubs, and forbs. The slope restricts the use of wheeled and tracked Typically, the surface is covered with a layer of needles, logging equipment. High-lead or other cable systems are leaves, and twigs about 1 inch thick. The surface layer is the best methods of logging. If the soil is excessively very dark grayish brown cobbly loam about 3 inches thick. disturbed when timber is harvested or logging roads are The next layer is dark brown gravelly loam about 4 inches built, a larger number of rock fragments is left on the thick. The upper 8 inches of the subsoil is brown very surface. Ripping landings when the soil is dry can improve gravelly clay loam. The lower 14 inches is light olive brown the growth of plants. very cobbly clay loam. Bedrock is at a depth of about 29 Properly designed road drainage systems that include inches. The depth to bedrock ranges from 20 to 40 inches. carefully located culverts help to control erosion. Road cuts In some areas the surface layer is very cobbly or stony. on this unit expose a large amount of fractured bedrock, which limits the response to seeding and mulching. Cut slopes are subject to slumping where Figure 8.-Cut slope slumping onto a road in an area of Gravecreek gravelly loam, 55 to 80 percent north slopes.

Included in this unit are small areas of Acker, Dubakella, effective rooting depth is 20 to 40 inches. Runoff is Dumont, and Norling soils; Rock outcrop and Pearsoll soils medium, and the hazard of water erosion is moderate. on ridges and convex slopes; poorly drained soils on This unit is used for timber production and wildlife concave slopes and near drainageways; and, on concave habitat. It is suited to the production of Douglas fir. slopes and foot slopes, soils that are similar to the Other species that grow on this unit include incense Gravecreek soil but have bedrock at a depth of more than cedar, Jeffrey pine, and Pacific madrone. The 40 inches. Also included are small areas of Gravecreek soils understory vegetation includes canyon live oak, that have slopes of less than 12 or more than 35 percent. common beargrass, and California fescue. Included areas make up about 20 percent of, the total On the basis of a 100-year site curve, the mean site acreage. index for Douglas fir is 90. The yield at culmination of the Permeability is moderately slow in the Gravecreek mean annual increment is 4,200 cubic feet per acre in a soil. Available water capacity is about 3 inches. The fully stocked, even-aged stand of trees at 60 years and 31,840 board feet per acre (Scribner rule) at 160 years. On the basis of a 50-year curve, the mean site 75F-Gravecreek cobbly loam, 35 to 55 percent south index is 65. slopes. This moderately deep, well drained soil is on The main limitations affecting timber production are hillslopes. It formed in colluvium derived from serpentinitic erosion, compaction, seedling mortality, and plant rock. Elevation is 2,200 to 4,300 feet. The mean annual competition. Also, the bedrock restricts root growth. As a precipitation is 45 to 55 inches, the mean annual result, windthrow is a hazard. temperature is 45 to 50 degrees F, and the average Wheeled and tracked logging equipment can be used in frost-free period is 100 to 160 days. The native vegetation is the less sloping areas, but cable yarding generally is safer mainly conifers and hardwoods and an understory of in the more sloping areas and results in less surface grasses, shrubs, and forbs. disturbance. In some areas stones on the surface can Typically, the surface is covered with a layer of needles, cause breakage of falling timber and can hinder yarding. If leaves, and twigs about 1 inch thick. The surface layer is the soil is excessively disturbed when timber is harvested or very dark grayish brown cobbly loam about 3 inches thick. logging roads are built, a larger number of rock fragments is The next layer is dark brown gravelly loam about 4 inches left on the surface. Using standard wheeled and tracked thick. The upper 8 inches of the subsoil is brown very equipment when the soil is moist causes rutting and gravelly clay loam. The lower 14 inches is light olive brown compaction. Puddling can occur when the soil is wet. Using very cobbly clay loam. Bedrock is at a depth of about 29 low-pressure ground equipment causes less damage to the inches. The depth to bedrock ranges from 20 to 40 inches. soil and helps to maintain productivity. Compaction can be In some areas the surface layer is very cobbly or stony. minimized by using suitable methods of harvesting, laying Included in this unit are small areas of Acker, Dubakella, out skid trails in advance, and harvesting timber when the and Norling soils; Rock outcrop and Pearsoll soils on ridges soil is least susceptible to compaction. Ripping skid trails and convex slopes; Dumont soils on concave slopes and on and landings when the soil is dry can improve the growth of the less sloping parts of the landscape; and, on concave plants. slopes and foot slopes, soils that are similar to the Properly designed road drainage systems that include Gravecreek soil but have bedrock at a depth of more than carefully located culverts help to control erosion Seeding, 40 inches. Also included are small areas of Gravecreek mulching, and benching areas that have been cut and filled soils that have slopes of less than 35 or more than 55 also help to control erosion. Steep yarding paths„ skid trails, percent. Included areas make up about 20 percent of the and firebreaks are subject to rilling and gullying unless they total acreage. are protected by a plant cover or adequate water bars, or Permeability is moderately slow in the Gravecreek both. Skid trails and unsurfaced roads may be impassable soil. Available water capacity is about 3 inches. The during rainy periods. Logging roads require suitable effective rooting depth is 20 to 40 inches. Runoff is rapid, surfacing for year-round use. and the hazard of water erosion is high. A high temperature in the surface layer during summer, This unit-is used for timber production and wildlife the low available water capacity, and a nutrient imbalance habitat. It is suited to the production of Douglas fir. caused by the serpentinitic rock increase the seedling Other species that grow on this unit include incense mortality rate. The large number of rock fragments in the cedar, Jeffrey pine, and Pacific madrone. The soil also increases the seedling mortality rate. To understory vegetation includes canyon live oak, compensate for the expected high mortality rate, the larger common beargrass, and California fescue. seedlings or a greater number of seedlings should be On the basis of a 100-year site curve, the mean site planted. When the timber is harvested, leaving some of the index for Douglas fir is 90. The yield at culmination of the larger trees unharvested provides shade for seedlings. mean annual increment is 4,200 cubic feet per acre in a Reforestation can be accomplished by planting Jeffrey pine, fully stocked, even-aged stand of trees at 60 years and ponderosa pine, and Douglas fir seedlings. 31,840 board feet per acre (Scribner rule) at 160 years. On Undesirable plants limit natural or artificial the basis of a 50-year curve, the mean site index is 65. reforestation unless intensive site preparation and The main limitations affecting timber production are the maintenance measures are applied. Mulching around slope, erosion, compaction, seedling mortality, and plant seedlings helps to maintain the moisture supply in competition. Also, the bedrock restricts root growth. As a summer and minimizes competition from undesirable result, windthrow is a hazard. understory plants. Wheeled and tracked logging equipment can be used in The vegetative site is Douglas Fir-Beargrass Forest, the less sloping areas, but cable yarding generally is safer Serpentine. and results in less surface disturbance. In some areas stones on the surface can cause breakage of falling The vegetative site is Douglas Fir-Beargrass Forest, timber and can hinder yarding. If the soil is excessively Serpentine. disturbed when timber is harvested or logging roads are built, a larger number of rock fragments is left on the 75G-Gravecreek cobbly loam, 55 to 80 percent south surface. Using standard wheeled and tracked equipment slopes. This moderately deep, well drained soil is on when the soil is moist causes rutting and compaction. hillslopes. It formed in colluvium derived from serpentinitic Puddling can occur when the soil is wet. Using rock. Elevation is 2,200 to 4,300 feet. The mean annual low-pressure ground equipment causes less damage to the precipitation is 45 to 55 inches, the mean annual soil and helps to maintain productivity. Compaction can be temperature is 45 to 50 degrees F, and the average minimized by using suitable methods of harvesting, laying frost-free period is 100 to 160 days. The native vegetation is out skid trails in advance, and harvesting timber when the mainly conifers and hardwoods and an understory of soil is least susceptible to compaction. Ripping skid trails grasses, shrubs, and forbs. and landings when the soil is dry can improve the growth of Typically, the surface is covered with a layer of needles, plants. leaves, and twigs about 1 inch thick. The surface layer is Properly designed road drainage systems that include very dark grayish brown cobbly loam about 3 inches thick. carefully located culverts help to control erosion Seeding, The next layer is dark brown gravelly loam about 4 inches mulching, and benching areas that have been cut and filled thick. The upper 8 inches of the subsoil is brown very also help to control erosion. Steep yarding paths, skid trails, gravelly clay loam. The lower 14 inches is light olive brown and firebreaks are subject to rilling and gullying unless they very cobbly clay loam. Bedrock is at a depth of about 29 are protected by a plant cover or adequate water bars, or inches. The depth to bedrock ranges from 20 to 40 inches. both. Cutbanks occasionally slump when the soil is In some areas the surface layer is very cobbly or stony. saturated. Included in this unit are small areas of Acker, Dubakella, Constructing logging roads on the steeper slopes can and Norling soils; Rock outcrop and Pearsoll soils on ridges result in a high risk of erosion. Material that is discarded and convex slopes; and soils that are similar to the when the roads are built can damage vegetation and is a Gravecreek soil but have bedrock at a depth of more than potential source of sedimentation. If the material becomes 40 inches. Also included are small areas of Gravecreek saturated, avalanches of debris can occur. End hauling of soils that have slopes of less than 55 or more than 80 the waste material minimizes damage to the vegetation percent. Included areas make up about 20 percent of the downslope and reduces the risk of sedimentation. Skid trails total acreage. and unsurfaced roads may be impassable during rainy Permeability is moderately slow in the Gravecreek periods. Logging roads require suitable surfacing for soil. Available water capacity is about 3 inches. The year-round use. effective rooting depth is 20 to 40 inches. Runoff is A high temperature in the surface layer during summer, rapid, and the hazard of water erosion is high. the low available water capacity, and a nutrient imbalance This unit is used for timber production and wildlife caused by the serpentinitic rock increase the seedling habitat. It is suited to the production of Douglas fir. mortality rate. The large number of rock fragments in the Other species that grow on this unit include incense soil also increases the seedling mortality rate. To cedar, Jeffrey pine, and Pacific madrone. The compensate for the expected high mortality rate, the larger understory vegetation includes canyon live oak, seedlings or a greater number of seedlings should be common beargrass, and California fescue. planted. When the timber is harvested, leaving some of the On the basis of a 100-year site curve, the mean site larger trees unharvested provides shade for seedlings. The index for Douglas fir is 90. The yield at culmination of the seedling mortality rate also can be reduced by providing mean annual increment is 4,200 cubic feet per acre in a artificial shade for seedlings. Reforestation can be fully stocked, even-aged stand of trees at 60 years and accomplished by planting Jeffrey pine, ponderosa pine, and 31,840 board feet per acre (Scribner rule) at 160 years. On Douglas fir seedlings. the basis of a 50-year curve, the mean site index is 65. Undesirable plants limit natural or artificial The main limitations affecting timber production are the reforestation unless intensive site preparation and slope, erosion, seedling mortality, and plant competition. maintenance measures are applied. Mulching around Also, the bedrock restricts root growth. As a result, seedlings helps to maintain the moisture supply in windthrow is a hazard. summer and minimizes competition from undesirable The slope restricts the use of wheeled and tracked understory plants. logging equipment. High-lead or other cable systems are the best methods of logging. In some areas stones on the surface can cause breakage of falling timber and can mean annual precipitation is 18 to 30 inches, the mean hinder yarding. If the soil is excessively disturbed when annual temperature is 50 to 54 degrees F, and the average timber is harvested or logging roads are built, a larger frost-free period is 150 to 180 days. The native vegetation is number of rock fragments is left on the surface. Ripping mainly grasses, sedges, and forbs. landings when the soil is dry can improve the growth of Typically, the surface layer is very dark grayish brown plants. silty clay loam about 7 inches thick. The next layer is very Properly designed road drainage systems that include dark grayish brown clay loam about 5 inches thick. The carefully located culverts help to control erosion. Road cuts upper 6 inches of the subsoil also is very dark grayish on this unit expose a large amount of fractured bedrock, brown clay loam. The lower 26 inches is very dark grayish which limits the response to seeding and mulching. Cut brown and dark grayish brown clay. The substratum is dark slopes are subject to slumping where the bedrock is highly grayish brown sandy clay loam about 6 inches thick. fractured or where rock layers are parallel to the slopes. Weathered bedrock is at a depth of about 50 inches. The Steep yarding paths and firebreaks are subject to rilling and depth to bedrock ranges from 40 to 60 inches. gullying unless they are protected by a plant cover or Included in this unit are small areas of Coleman and adequate water bars, or both. Medford soils on the higher terraces; Brader, Debenger, Building logging roads at midslope requires extensive and Langellain soils on convex slopes; Cove and Padigan cutting and filling and removes land from production. soils; and soils that are similar to the Gregory soil but have Material that is discarded when the roads are built can bedrock at a depth of less than 40 or more than 60 inches. damage vegetation and is a potential source of Also included are small areas of Gregory soils that have sedimentation. If the material becomes saturated, slopes of more than 3 percent. Included areas make up avalanches of debris can occur. End hauling of the waste about 20 percent of the total acreage. material minimizes damage to the vegetation downslope Permeability is slow in the Gregory soil. Available water and reduces the risk of sedimentation. Unsurfaced roads capacity is about 9 inches. The effective rooting depth is may be impassable during rainy periods. Logging roads limited by the water table, which is within a depth of 1 foot require suitable surfacing for year-round use. from December through May. Runoff is slow, and the A high temperature in the surface layer during summer, hazard of water erosion is slight. the low available water capacity, and a nutrient imbalance This unit is used mainly for pasture. It also is used for caused by the serpentinitic rock increase the seedling irrigated crops, such as tree fruit, small grain, and corn for mortality rate. The large number of rock fragments in the silage. A few areas are used for grass-legume hay or for soil also increases the seedling mortality rate. To homesite development. compensate for the expected high mortality rate, the larger This unit is suited to permanent pasture. It is limited seedlings or a greater number of seedlings should be mainly by the wetness, the high content of clay, and a slow planted. When the timber is harvested, leaving some of the rate of water intake. Crops that require good drainage can larger trees unharvested provides shade for seedlings. The be grown if a properly designed drainage system is seedling mortality rate also can be reduced by providing installed. The ability of tile drains to remove subsurface artificial shade for seedlings. Reforestation can be water from the soil is limited because of the slow accomplished by planting Jeffrey pine, ponderosa pine, and permeability. Douglas fir seedlings. In summer, irrigation is needed for the maximum Undesirable plants limit natural or artificial production. of most forage crops. Sprinkler irrigation is the reforestation unless intensive site preparation and best method of applying water. Furrow, border, corrugation, maintenance measures are applied. Mulching around and trickle irrigation systems also are suitable. The system seedlings helps to maintain the moisture supply in used generally is governed by the crop that is grown. For the summer and minimizes competition from undesirable efficient application and removal of surface irrigation water, understory plants. land leveling is needed. Because of the slow permeability The vegetative site is Douglas Fir-Beargrass Forest, and the water table, water applications should be regulated Serpentine. so that the water does not stand on the surface and damage the crop. Land smoothing and open ditches can reduce 76A-Gregory silty clay loam, 0 to 3 percent slopes. surface wetness. The use of pipe, ditch lining, or drop This deep, poorly drained soil is on stream terraces. It structures in irrigation ditches reduces water loss and the formed in alluvium derived dominantly from metamorphic hazard of erosion. rock. Elevation is 1,000 to 2,000 feet. The Wetness limits the choice of suitable forage plants and the period of cutting or grazing and increases the risk of degrees F, and the average frost-free period is less than winterkill. The high content of clay severely limits tillage and 100 days. The native vegetation is mainly conifers and an root growth. Deep cracks form as the soil dries in summer. understory of grasses, shrubs, and forbs. Proper stocking rates, pasture rotation, and restricted Typically, the surface is covered with a layer of needles grazing during wet periods help to keep pastures in good and twigs about 1 inch thick. The surface layer is dark condition and protect the soil from erosion. Grazing when reddish brown stony loam about 3 inches thick. The next the soil is wet results in compaction of the surface layer, layer is dark reddish brown very cobbly loam about 10 poor tilth, and excessive runoff. Periodic mowing and inches thick. The upper 10 inches of the subsoil also is dark clipping help to maintain uniform plant growth, discourage reddish brown very cobbly loam. The lower 19 inches is selective grazing, and reduce the extent of clumpy growth. dark reddish brown extremely gravelly clay loam. Fertilizer is needed to ensure the optimum growth of Weathered bedrock is at a depth of about 42 inches. The grasses and legumes. Grasses respond to nitrogen, and depth to bedrock ranges from 40 to 60 inches. legumes respond to sulfur and phosphorus. Included in this unit are small areas of Merlin and Royst Solid-set sprinkler irrigation is the best method of soils, Rock outcrop and Rubble land on ridges and convex controlling frost and providing adequate moisture for tree slopes, Pinehurst soils on the less sloping parts of the fruit. Compaction can be minimized by limiting the use of landscape, and soils that are similar to the Greystoke soil equipment when the soil is wet and by planting a cover but have bedrock at a depth of more than 60 inches. Also crop. A permanent sod crop helps to control runoff. included are small areas of Greystoke soils that have This unit is poorly suited to homesite development. The slopes of less than 35 or more than 55 percent. Included main limitations are the wetness, a high shrink-swell areas make up about 20 percent of the total acreage. potential, the slow permeability, and low strength. Permeability is moderately slow in the Greystoke soil. This unit is poorly suited to standard systems of waste Available water capacity is about 4 inches. The effective disposal because of the wetness and the slow permeability. rooting depth is 40 to 60 inches. Runoff is rapid, and the Alternative waste disposal systems may function properly hazard of water erosion is high. on this unit. Suitable included soils are throughout the unit. This unit is used for timber production, livestock Onsite investigation is needed to locate such soils. grazing, and wildlife habitat. A drainage system is needed if roads or building This unit is suited to the production of Douglas fir and foundations are constructed on this unit. The wetness can ponderosa pine. Other species that grow on this unit be reduced by installing drainage tile around footings. include incense cedar, white fir, and sugar pine. The Properly designing foundations and footings, diverting understory vegetation includes tall Oregongrape, runoff away from the buildings, and backfilling with material pachystima, and western fescue. that has a low shrink-swell potential help to prevent the On the basis of a 100-year site curve, the mean site structural damage caused by shrinking and swelling. index for Douglas fir is 90. The yield at culmination of the Properly designing buildings and roads helps to offset the mean annual increment is 4,200 cubic feet per acre in a limited ability of the soil to support a load. fully stocked, even-aged stand of trees at 60 years and Revegetating as soon as possible helps to control 31,840 board feet per acre (Scribner rule) at 160 years. On erosion in disturbed areas around construction sites. the basis of a 50-year curve, the mean site index is 65. Topsoil can be stockpiled and used to reclaim areas On the basis of a 100-year site curve, the mean site disturbed during construction. In many areas it may be index for ponderosa pine is 90. The yield at culmination of necessary to haul in topsoil for lawns and gardens. the mean annual increment is 3,400 cubic feet per acre in a Because of a low amount of rainfall in summer, irrigation is fully stocked, even-aged stand of trees at 40 years and needed in areas that support lawn grasses, shrubs, vines, 37,960 board feet per acre (Scribner rule) at 130 years. shade trees, or ornamental trees. The main limitations affecting timber production are the The vegetative site is Poorly Drained Bottom. slope, erosion, compaction, and plant competition. Wheeled and tracked logging equipment can be used in the less 77F-Greystoke stony loam, 35 to 55 percent north sloping areas, but cable yarding generally is safer and slopes. This deep, well drained soil is on hillslopes. It results in less surface disturbance. If the soil is excessively formed in colluvium derived from andesite. Elevation is disturbed when timber is harvested or logging roads are 3,000 to 4,800 feet. The mean annual precipitation is 20 to built, a larger number of rock fragments is left on the 30 inches, the mean annual temperature is 42 to 46 surface. Using standard wheeled and tracked equipment when the soil is moist overstory canopy and increase the production of causes rutting and compaction. Puddling can occur when understory vegetation. Areas that support a large the soil is wet. Using low-pressure ground equipment amount of competing vegetation can be improved by causes less damage to the soil and helps to maintain prescribed burning or by chemical or mechanical productivity: Compaction can be minimized by using treatment. Seeding disturbed areas to suitable plants suitable methods of harvesting, laying out skid trails in increases forage production and reduces the risk of advance, and harvesting timber when the soil is least erosion. susceptible to compaction. Ripping skid trails and landings The vegetative site is Douglas Fir-Mixed Pine-Sedge when the soil is dry can improve the growth of plants. Forest. Properly designed road drainage systems that include carefully located culverts help to control erosion. Seeding, 77G-Greystoke stony loam, 55 to 75 percent north mulching, and benching areas that have been cut and filled slopes. This deep, well drained soil is on hillslopes. It also help to control erosion. Steep yarding paths, skid trails, formed in colluvium derived from andesite. Elevation is and firebreaks are subject to rilling and gullying unless they 3,000 to 4,800 feet. The mean annual precipitation is 20 to are protected by a plant cover or adequate water bars, or 30 inches, the mean annual temperature is 42 to 46 both. Cutbanks occasionally slump when the soil is degrees F, and the average frost-free period is less than saturated. 100 days. The native vegetation is mainly conifers and an Constructing logging roads on the steeper slopes can understory of grasses, shrubs, and .forbs. result in a high risk of erosion. Building the roads at Typically, the surface is covered with a layer of needles midslope requires extensive cutting and filling and removes and twigs about 1 inch thick. The surface layer is dark land from production. Material that is discarded when the reddish brown stony loam about 3 inches thick. The next roads are built can damage vegetation and is a potential layer is dark reddish brown very cobbly loam about 10 source of sedimentation. If the material becomes saturated, inches thick. The upper 10 inches of the subsoil also is dark avalanches of debris can occur. End hauling of the waste reddish brown very cobbly loam. The lower 19 inches is material minimizes damage to the vegetation downslope dark reddish brown extremely gravelly clay loam. and reduces the risk of sedimentation. Skid trails and Weathered bedrock is at a depth of about 42 inches. The unsurfaced roads may be impassable during rainy periods. depth to bedrock ranges from 40 to 60 inches. Logging roads require suitable surfacing for year-round use. Included in this unit are small areas of Merlin and Royst Undesirable plants limit natural or artificial reforestation soils, Rock outcrop and Rubble land on ridges and convex unless intensive site preparation and maintenance slopes, Pinehurst soils on the less sloping parts of the measures are applied. Reforestation can be accomplished landscape, and soils that are similar to the Greystoke soil by planting ponderosa pine and Douglas fir seedlings. but have bedrock at a depth of more than 60 inches. Also Mulching around seedlings helps to maintain the moisture included are small areas of Greystoke soils that have supply in summer and minimizes competition from slopes of less than 55 or more than 75 percent. Included undesirable understory plants. areas make up about 20 percent of the total acreage. The main limitations affecting livestock grazing are Permeability is moderately slow in the Greystoke soil. erosion, compaction, and the slope. The native vegetation Available water capacity is about 4 inches. The effective suitable for grazing includes western fescue, mountain rooting depth is 40 to 60 inches. Runoff is rapid, and the brome, and tall trisetum. If the understory is overgrazed, the hazard of water erosion is high. proportion of preferred forage plants decreases and the This unit is used for timber production, livestock proportion of less preferred forage plants increases. grazing, and wildlife habitat. A planned grazing system that includes timely deferment This unit is suited to the production of Douglas fir and of grazing, rotation grazing, and proper livestock distribution ponderosa pine. Other species that grow on this unit helps to prevent overgrazing of the understory and damage include incense cedar, white fir, and sugar pine. The to the soil. Grazing should be delayed until the more understory vegetation includes tall Oregongrape, desirable forage plants have achieved enough growth to pachystima, and western fescue. withstand grazing pressure and the soil is firm enough to On the basis of a 100-year site curve, the mean site withstand trampling by livestock. index for Douglas fir is 90. The yield at culmination of the Thinning, logging, and fire reduce the density of the mean annual increment is 4,200 cubic feet per acre in a fully stocked, even-aged stand of trees at 60 years and 31,840 board feet per acre (Scribner rule) at 160 years. On the basis of a 50-year curve, the mean site understory and damage to the soil. Grazing should be index is 65. delayed until the more desirable forage plants have On the basis of a 100-year site curve, the mean site achieved enough growth to withstand grazing pressure index for ponderosa pine is 90. The yield at culmination of and the soil is firm enough to withstand trampling by the mean annual increment is 3,400 cubic feet per acre in a livestock. fully stocked, even-aged stand of trees at 40 years and Thinning, logging, and fire reduce the density of the 37,960 board feet per acre (Scribner rude) at 130 years. overstory canopy and increase the production of The main limitations affecting timber production are the understory vegetation. Areas that support a large amount slope, erosion, and plant competition. The slope restricts of competing vegetation can be improved by prescribed the use of wheeled and tracked logging equipment. burning or by chemical or mechanical treatment. Seeding High-lead or other cable systems are the best methods of disturbed areas to suitable plants increases forage logging. If the soil is excessively disturbed when timber is production and reduces the risk of erosion. harvested or logging roads are built, a larger number of rock The vegetative site is Douglas Fir-Mixed Pine-Sedge fragments is left on the surface. Ripping landings when the Forest. soil is dry can improve the growth of plants. Properly designed road drainage systems that include 78F-Greystoke stony loam, 35 to 55 percent south carefully located culverts help to control erosion. Road cuts slopes. This deep, well drained soil is on hillslopes. It can expose a large amount of fractured bedrock, which formed in colluvium derived from andesite. Elevation is limits the response to seeding and mulching. Steep yarding 3,000 to 5,200 feet. The mean annual precipitation is 20 to paths and firebreaks are subject to rilling and gullying 30 inches, the mean annual temperature is 42 to 46 unless they are protected by a plant cover or adequate degrees F, and the average frost-free period is less than water bars, or both. Cutbanks occasionally slump when the 100 days. The native vegetation is mainly conifers and an soil is saturated. understory of grasses, shrubs, and forbs. Building logging roads at midslope requires extensive Typically, the surface is covered with a layer of needles cutting and filling and removes land from production. and twigs about 1 inch thick. The surface layer is dark Material that is discarded when the roads are built can reddish brown stony loam about 3 inches thick. The next damage vegetation and is a potential source of layer is dark reddish brown very cobbly loam about 10 sedimentation. If the material becomes saturated, inches thick. The upper 10 inches of the subsoil also is dark avalanches of debris can occur. End hauling of the waste reddish brown very cobbly loam. The lower 19 inches is material minimizes damage to the vegetation downslope dark reddish brown extremely gravelly clay loam. and reduces the risk of sedimentation. Skid trails and Weathered bedrock is at a depth of about 42 inches. The unsurfaced roads may be impassable during rainy periods. depth to bedrock ranges from 40 to 60 inches. Logging roads require suitable surfacing for year-round use. Included in this unit are small areas of Merlin and Royst Undesirable plants limit natural or artificial reforestation soils, Rock outcrop and Rubble land on ridges and convex unless intensive site preparation and maintenance slopes, Pinehurst soils on the less sloping parts of the measures are applied. Reforestation can be accomplished landscape, and soils that are similar to the Greystoke soil by planting ponderosa pine and Douglas fir seedlings. but have bedrock at a depth of more than 60 inches. Also Mulching around seedlings helps to maintain the moisture included are small areas of Greystoke soils that have supply in summer and minimizes competition from slopes of less than 35 or more than 55 percent. Included undesirable understory plants. areas make up about 20 percent of the total acreage. The main limitations affecting livestock grazing are Permeability is moderately slow in the Greystoke soil. erosion, compaction, and the slope. The native vegetation Available water capacity is about 4 inches. The effective suitable for grazing includes western fescue, mountain rooting depth is 40 to 60 inches. Runoff is rapid, and the brome, and tall trisetum. If the understory is overgrazed, hazard of water erosion is high. the proportion of preferred forage plants decreases and the This unit is used for timber production, livestock proportion of less preferred forage plants increases. grazing, and wildlife habitat. A planned grazing system that includes timely deferment This unit is suited to the production of Douglas fir and of grazing, rotation grazing, and proper livestock ponderosa pine. Other species that grow on this unit distribution helps to prevent overgrazing of the include incense cedar, white fir, and sugar pine. The understory vegetation includes tall Oregongrape, summer and the low available water capacity increase the pachystima, and western fescue. seedling mortality rate. The large number of rock fragments On the basis of a 100-year site curve, the mean site in the soil also increases the seedling mortality rate. To index for Douglas fir is 85. The yield at culmination of the compensate for the expected high . mortality rate, the larger mean annual increment is 4,480 cubic feet per acre in a seedlings or a greater number of seedlings should be fully stocked, even-aged stand of trees at 70 years and planted. When the timber is harvested, leaving some of the 27,520 board feet per acre (Scribner rule) at 160 years. On larger trees unharvested provides shade for seedlings. The the basis of a 50-year curve, the mean site index is 60. seedling mortality rate also can be reduced by providing On the basis of a 100-year site curve, the mean site artificial shade for seedlings. Reforestation can be index for ponderosa pine is 80. The yield at culmination of accomplished by planting ponderosa pine and Douglas fir the mean annual increment is 2,670 cubic feet per acre in a seedlings. fully stocked, even-aged stand of trees at 40 years and Undesirable plants limit natural or artificial 33,750 board feet per acre (Scribner rule) at 150 years. reforestation unless intensive site preparation and The main limitations affecting timber production are the maintenance measures are applied. Mulching around slope, erosion, compaction, seedling mortality, and plant seedlings helps to maintain the moisture supply in competition. Wheeled and tracked logging equipment can summer and minimizes competition from undesirable be used in the less sloping areas, but cable yarding understory plants. generally is safer and results in less surface disturbance. If The main limitations affecting livestock grazing are the soil is excessively disturbed when timber is harvested erosion, compaction, and the slope. The native vegetation or logging roads are built, a larger number of rock suitable for grazing includes western fescue, mountain fragments is left on the surface. Using standard wheeled brome, and tall trisetum. If the understory is overgrazed, and tracked equipment when the soil is moist causes rutting the proportion of preferred forage plants decreases and the and compaction. Puddling can occur when the soil is wet. proportion of less preferred forage plants increases. Using low-pressure ground equipment causes less damage A planned grazing system that includes timely deferment to the soil and helps to maintain productivity. Compaction of grazing, rotation grazing, and proper livestock distribution can be minimized by using suitable methods of harvesting, helps to prevent overgrazing of the understory and damage laying out skid trails in advance, and harvesting timber to the soil. Grazing should be delayed until the more when the soil is least susceptible to compaction. Ripping desirable forage plants have achieved enough growth to skid trails and landings when the soil is dry can improve the withstand grazing pressure and the soil is firm enough to growth of plants. withstand trampling by livestock. Properly designed road drainage systems that include Thinning, logging, and fire reduce the density of the carefully located culverts help to control erosion. Seeding, overstory canopy and increase the production of mulching, and benching areas that have been cut and filled understory vegetation. Areas that support a large amount also help to control erosion. Steep yarding paths, skid trails, of competing vegetation can be improved by prescribed and firebreaks are subject to rilling and gullying unless they burning or by chemical or mechanical treatment. Seeding are protected by a plant cover or adequate water bars, or disturbed areas to suitable plants increases forage both. Cutbanks occasionally slump when the soil is production and reduces the risk of erosion. saturated. The vegetative site is Douglas Fir-Mixed Pine-Sedge Constructing logging roads on the steeper slopes can Forest. result in a high risk of erosion. Building the roads at midslope requires extensive cutting and filling and removes 79E-Greystoke-Pinehurst complex, 12 to 35 land from production. Material that is discarded when the percent north slopes. This map unit is on hillslopes. roads are built can damage vegetation and is a potential Elevation is 3,500 to 4,800 feet. The mean annual source of sedimentation. If the material becomes saturated, precipitation is 20 to 30 inches, the mean annual avalanches of debris can occur. End hauling of the waste temperature is 42 to 46 degrees F, and the average material minimizes damage to the vegetation downslope frost-free period is less than 100 days. The native and reduces the risk of sedimentation. Skid trails and vegetation is mainly conifers and an understory of unsurfaced roads may be impassable during rainy periods. grasses, shrubs, and forbs. Logging roads require suitable surfacing for year-round use. This unit is about 60 percent Greystoke soil and 25 A high temperature in the surface layer during percent Pinehurst soil. The components of this unit occur as areas so intricately intermingled that mapping them separately was not practical at the scale used. The yield at culmination of the mean annual increment is Included in this unit are small areas of Merlin and Royst 3,400 cubic feet per acre in a fully stocked, even-aged soils and Rock outcrop on ridges and convex slopes, stand of trees at 40 years and 37,960 board feet per acre Kanutchan soils near drainageways and on concave slopes, (Scribner rule) at 130 years. and soils that are similar to the Pinehurst soil but have On the basis of a 100-year site curve, the mean site bedrock within a depth of 60 inches. Also included are small index for Douglas fir is 100 on the Pinehurst soil. The yield areas of Greystoke and Pinehurst soils that have slopes of at culmination of the mean annual increment is 5,040 cubic less than 12 or more than 35 percent. Included areas make feet per acre in a fully stocked, even-aged stand of trees at up about 15 percent of the total acreage. 60 years and 39,750 board feet per acre (Scribner rule) at The Greystoke soil is deep and well drained. It formed in 150 years. On the basis of a 50-year curve, the mean site residuum and colluvium derived dominantly from andesite. index is 75. Typically, the surface is covered with a layer of needles and On the basis of a 100-year site curve, the mean site twigs about 1 inch thick. The surface layer is dark reddish index for ponderosa pine is 95 on the Pinehurst soil. The brown stony loam about 3 inches thick. The next layer is yield at culmination of the mean annual increment is 3,760 dark reddish brown very cobbly loam about 10 inches thick. cubic feet per acre in a fully stocked, even-aged stand of The upper 10 inches of the subsoil also is dark reddish trees at 40 years and 43,160 board feet per acre (Scribner brown very cobbly loam. The lower 19 inches is dark reddish rule) at 130 years. brown extremely gravelly clay loam. Weathered bedrock is The main limitations affecting timber production are at a depth of about 42 inches. The depth to bedrock ranges erosion, compaction, and plant competition. Wheeled and from 40 to 60 inches. tracked logging equipment can be used in the less sloping Permeability is moderately slow in the Greystoke soil. areas, but cable yarding generally is safer in the more Available water capacity is about 4 inches. The effective sloping areas and results in less surface disturbance. If the rooting depth is 40 to 60 inches. Runoff is medium, and the soils are excessively disturbed when timber is harvested or hazard of water erosion is moderate. logging roads are built, a larger number of rock fragments is The Pinehurst soil is very deep and well drained. It left on the surface. Using standard wheeled and tracked formed in colluvium derived dominantly from andesite. equipment when the soils are moist causes rutting and Typically, the surface is covered with a layer of needles and compaction. Puddling can occur when the soils are wet. twigs about 1 inch thick. The surface layer is dark reddish Using low-pressure ground equipment causes less damage brown loam about 15 inches thick. The subsoil is dark to the soil and helps to maintain productivity. Compaction reddish brown clay loam about 45 inches thick. The depth can be minimized by using suitable methods of harvesting, to bedrock is 60 inches or more. In some areas the surface laying out skid trails in advance, arid harvesting timber when layer is stony. the soils are least susceptible to compaction. Ripping skid Permeability is moderately slow in the Pinehurst soil. trails and landings when the soils are dry can improve the Available water capacity is about 10 inches. The effective growth of plants. rooting depth is 60 inches or more. Runoff is medium, and Properly designed road drainage systems that include the hazard of water erosion is moderate. carefully located culverts help to control erosion. Seeding, This unit is used for timber production, livestock mulching, and benching areas that have been cut and filled grazing, and wildlife habitat. also help to control erosion. Steep yarding paths, skid trails, This unit is suited to the production of Douglas fir and and firebreaks are subject to rilling and gullying unless they ponderosa pine. Other species that grow on this unit are protected by a plant cover or adequate water bars, or include incense cedar, white fir, and sugar pine. The both. Skid trails and unsurfaced roads may be impassable understory vegetation includes tall Oregongrape, during rainy periods. Logging roads require suitable pachystima, and western fescue. surfacing for year-round use. On the basis of a 100-year site curve, the mean site Undesirable plants limit natural or artificial reforestation index for Douglas fir is 90 on the Greystoke soil. The yield unless intensive site preparation and maintenance at culmination of the mean annual increment is 4,200 cubic measures are applied. Reforestation can be accomplished feet per acre in a fully stocked, even-aged stand of trees at by planting ponderosa pine and Douglas fir seedlings. 60 years and 31,840 board feet per acre (Scribner rule) at Mulching around seedlings helps to maintain the moisture 160 years. On the basis of a 50-year curve, the mean site supply in summer and minimizes competition from index is 65. undesirable understory plants. On the basis of a 100-year site curve, the mean site Severe frost can damage or kill seedlings. In the less index for ponderosa pine is 90 on the Greystoke soil. sloping areas where air drainage may be restricted, proper next layer is dark reddish brown very cobbly loam about 10 timber harvesting methods can reduce the effect of frost on inches thick. The upper 10 inches of the subsoil also is dark regeneration. reddish brown very cobbly loam. The lower 19 inches is The main limitations affecting livestock grazing are dark reddish brown extremely gravelly clay loam. compaction and erosion. The native vegetation suitable for Weathered bedrock is at a depth of about 42 inches. The grazing includes western fescue, mountain brome, and tall depth to bedrock ranges from 40 to 60 inches. trisetum. If the understory is overgrazed, the proportion of Permeability is moderately slow in the Greystoke soil. preferred forage plants decreases and the proportion of Available water capacity is about 4 inches. The effective less preferred forage plants increases. rooting depth is 40 to 60 inches. Runoff is medium, and the A planned grazing system that includes timely deferment hazard of water erosion is moderate. of grazing, rotation grazing, and proper livestock distribution The Pinehurst soil is very deep and well drained. It helps to prevent overgrazing of the understory and damage formed in colluvium derived dominantly from andesite. to the soils. Grazing should be delayed until the more Typically, the surface is covered with a layer of needles and desirable forage plants have achieved enough growth to twigs about 1 inch thick. The surface layer is dark reddish withstand grazing pressure and the soils are firm enough to brown loam about 15 inches thick. The subsoil is dark withstand trampling by livestock. reddish brown clay loam about 45 inches thick. The depth Thinning, logging, and fire reduce the density of the to bedrock is 60 inches or more. In some areas the surface overstory canopy and increase the production of layer is stony. understory vegetation. Areas that support a large amount Permeability is moderately slow in the Pinehurst soil. of competing vegetation can be improved by prescribed Available water capacity is about 10 inches. The effective burning or by chemical or mechanical treatment. Seeding rooting depth is 60 inches or more. Runoff is medium, and disturbed areas to suitable plants increases forage the hazard of water erosion is moderate. production and reduces the risk of erosion. This unit is used for timber production, livestock The vegetative site is Douglas Fir-Mixed Pine-Sedge grazing, and wildlife habitat. Forest. This unit is suited to the production of Douglas fir and ponderosa pine. Other species that grow on this unit 80E-Greystoke-Pinehurst complex, 12 to 35 include incense cedar, white fir, and sugar pine. The percent south slopes. This map unit is on hillslopes. understory vegetation includes tall Oregongrape, Elevation is 3,500 to 4,800 feet. The mean annual pachystima, and western fescue. precipitation is 20 to 30 inches, the mean annual On the basis of a 100-year site curve, the mean site temperature is 42 to 46 degrees F, and the average index for Douglas fir is 85 on the Greystoke soil. The yield frost-free period is less than 100 days. The native at culmination of the mean annual increment is 4,480 cubic vegetation is mainly conifers and an understory of feet per acre in a fully stocked, even-aged stand of trees at grasses, shrubs, and forbs. 70 years and 37,520 board feet per acre (Scribner rule) at This unit is about 60 percent Greystoke soil and 25 160 years. On the basis of a 50-year curve, the mean site percent Pinehurst soil. The components of this unit occur index is 60. as areas so intricately intermingled that mapping them On the basis of a 100-year site curve, the mean site separately was not practical at the scale used. index for ponderosa pine is 80 on the Greystoke soil. The Included in this unit are small areas of Merlin and Royst yield at culmination of the mean annual increment is 2,670 soils and Rock outcrop on ridges and convex slopes, cubic feet per acre in a fully stocked, even-aged stand of Kanutchan soils near drainageways and on concave slopes, trees at 40 years and 33,750 board feet per acre (Scribner and soils that are similar to the Pinehurst soil but have rule) at 150 years. bedrock within a depth of 60 inches. Also included are small On the basis of a 100-year site curve, the mean site areas of Greystoke and Pinehurst soils that have slopes of index for Douglas fir is 95 on the Pinehurst soil. The yield less than 12 or more than 35 percent. Included areas make at culmination of the mean annual increment is 4,620 cubic up about 15 percent of the total acreage. feet per acre in a fully stocked, even-aged stand of trees at The Greystoke soil is deep and well drained. It formed in 60 years and 37,120 board feet per acre (Scribner rule) at colluvium derived dominantly from andesite. Typically, the 160 years. On the basis of a 50-year curve, the mean site surface is covered with a layer of needles and twigs about 1 index is 65. inch thick. The surface layer is dark reddish brown stony On the basis of a 100-year site curve, the mean site loam about 3 inches thick. The index for ponderosa pine is 85 on the Pinehurst soil. The yield at culmination of the mean annual increment is 3,080 cubic feet per acre in a fully stocked, even- aged stand of trees at 40 years and 38,700 board feet per for grazing includes western fescue, mountain brome, and acre (Scribner rule) at 150 years. tall trisetum. If the understory is overgrazed, the proportion The main limitations affecting timber production are of preferred forage plants decreases and the proportion of erosion, compaction, plant competition, and seedling less preferred forage plants increases. mortality. Wheeled and tracked logging equipment can be A planned grazing system that includes timely deferment used in the less sloping areas, but cable yarding generally of grazing, rotation grazing, and proper livestock distribution is safer in the more sloping areas and results in less surface helps to prevent overgrazing of the understory and damage disturbance. If the soils are excessively disturbed when to the soils. Grazing should be delayed until the more timber is harvested or logging roads are built, a larger desirable forage plants have achieved enough growth to number of rock fragments is left on the surface. Using withstand grazing pressure and the soils are firm enough to standard wheeled and tracked equipment when the soils withstand trampling by livestock. are moist causes rutting and compaction. Puddling can Thinning, logging, and fire reduce the density of the occur when the soils are wet. Using low-pressure ground overstory canopy and increase the production of equipment causes less damage to the soil and helps to understory vegetation. Areas that support a large amount maintain productivity. Compaction can be minimized by of competing vegetation can be improved by prescribed using suitable methods of harvesting, laying out skid trails in burning or by chemical or mechanical treatment. Seeding advance, and harvesting timber when the soils are least disturbed areas to suitable plants increases forage susceptible to compaction. Ripping skid trails and landings production and reduces the risk of erosion. when the soils are dry can improve the growth of plants. The vegetative site is Douglas Fir-Mixed Pine-Sedge Properly designed road drainage systems that include Forest. carefully located culverts help to control erosion. Seeding, mulching, and benching areas that have been cut and filled 81G-Heppsie clay, 35 to 70 percent north slopes. also help to control erosion. Steep yarding paths, skid trails, This moderately deep, well drained soil is on hillslopes. It and firebreaks are subject to rilling and gullying unless they formed in colluvium derived dominantly from tuff, breccia, are protected by a plant cover or adequate water bars, or and andesite. Elevation is 2,000 to 4,000 feet. The mean both. Skid trails and unsurfaced roads may be impassable annual precipitation is 18 to 35 inches, the mean annual during rainy periods. Logging roads require suitable temperature is 45 to 52 degrees F, and the average surfacing for year-round use. frost-free period is 100 to 170 days. The native vegetation Undesirable plants limit natural or artificial reforestation is mainly hardwoods and conifers and an understory of unless intensive site preparation and maintenance grasses, shrubs, and forbs. measures are applied. Reforestation can be accomplished Typically, the surface layer is very dark brown and very by planting ponderosa pine and Douglas fir seedlings. dark grayish brown clay about 15 inches thick. The subsoil Mulching around seedlings helps to maintain the moisture is dark brown gravelly clay about 9 inches thick. Weathered supply in summer and minimizes competition from bedrock is at a depth of about 24 inches. The depth to undesirable understory plants. bedrock ranges from 20 to 40 inches. In some areas the A high temperature in the surface layer and an surface layer is stony. insufficient moisture supply in summer increase the Included in this unit are small areas of Rock outcrop and seedling mortality rate. The large number of rock fragments McMullin soils; Carney and Medco soils on concave slopes in the Greystoke soil also increases the seedling mortality and on the less sloping parts of the landscape; McNull, rate. To compensate for the expected high mortality rate, Skookum, and Tablerock soils; and, on ridges and convex the larger seedlings or a greater number of seedlings slopes, soils that are similar to the Heppsie soil but have should be planted. When the timber is harvested, leaving bedrock within a depth of 20 inches. Also included are small some of the larger trees unharvested provides shade for areas of Heppsie soils that have slopes of less than 35 or seedlings. more than 70 percent. Included areas make up about 20 Severe frost can damage or kill seedlings. In the less percent of the total acreage. sloping areas where air drainage may be restricted, proper Permeability is slow in the Heppsie soil. Available timber harvesting methods can reduce the effect of frost on water capacity is about 4 inches. The effective rooting regeneration. depth is 20 to 40 inches. Runoff is rapid, and the hazard The main limitations. affecting livestock grazing are of water erosion is high. compaction and erosion. The native vegetation suitable This unit is used for livestock grazing and wildlife habitat. The main limitations affecting livestock grazing are erosion, compaction, the slope, droughtiness, and the tuff, breccia, and andesite. Typically, the surface layer is clayey surface layer. The vegetation suitable for grazing very dark brown and very dark grayish brown clay about 15 includes Idaho fescue, prairie junegrass, and California inches thick. The subsoil is dark brown gravelly clay about 9 brome. If the range is overgrazed, the proportion of inches thick. Weathered bedrock is at a depth of about 24 preferred forage plants decreases and the proportion of inches. The depth to bedrock ranges from 20 to 40 inches. less preferred forage plants increases. Grazing should be In some areas the surface layer is stony. delayed until the more desirable forage plants have Permeability is slow in the Heppsie soil. Available achieved enough growth to withstand grazing pressure and water capacity is about 4 inches. The effective rooting the soil is firm enough to withstand trampling by livestock. depth is 20 to 40 inches. Runoff is rapid, and the hazard This unit is poorly suited to range seeding. The main of water erosion is high. limitations are the slope, droughtiness, and the clayey The McMullin soil is shallow and well drained. It formed surface layer. The plants selected for seeding should be in colluvium derived dominantly from andesite. Typically, those that meet the seasonal requirements of livestock or the surface layer is dark reddish brown gravelly loam about wildlife, or both. 7 inches thick. The subsoil is dark reddish brown gravelly The slope limits access by livestock and results in clay loam about 10 inches thick. Bedrock is at a depth of overgrazing of the less sloping areas. Constructing trails or about 17 inches. The depth to bedrock ranges from 12 to walkways allows livestock to graze in areas where access is 20 inches. In some areas the surface layer is stony. limited. Permeability is moderate in the McMullin soil. Available Suitable management practices on this unit include water capacity is about 2 inches. The effective rooting depth proper grazing use, deferred grazing, rotation grazing, and is 12 to 20 inches. Runoff is rapid, and the hazard of water brush control. Areas that support a large amount of erosion is high. competing vegetation can be improved by chemical or This unit is used for livestock grazing and wildlife habitat. mechanical treatment. The use of ground equipment is not The main limitations affecting livestock grazing are erosion, practical because of stones on the surface and the slope. compaction, the slope, and droughtiness. The McMullin soil This unit is limited as a site for livestock watering also is limited by the depth to bedrock and the Heppsie soil ponds and other water impoundments because of the by the clayey surface layer. The vegetation suitable for slope. grazing includes Idaho fescue, prairie junegrass, bluebunch The vegetative site is Droughty North, 18- to 35-inch wheatgrass, and pine bluegrass. If the range is overgrazed, precipitation zone. the proportion of preferred forage plants decreases and the proportion of less preferred forage plants increases. Grazing 82G-Heppsie-McMullin complex, 35 to 70 percent should be delayed until the more desirable forage plants south slopes. This map unit is on hillslopes. Elevation is have achieved enough growth to withstand grazing pressure 2,000 to 4,000 feet. The mean annual precipitation is 18 to and the soils are firm enough to withstand trampling by 35 inches, the mean annual temperature is 45 to 52 livestock. degrees F, and the average frost-free period is 100 to 170 Suitable management practices on this unit include days. The native vegetation is mainly hardwoods and an proper grazing use, deferred grazing, rotation grazing, and understory of grasses, shrubs, and forbs. brush control. Areas that support a large amount of This unit is about 60 percent Heppsie soil and 20 competing vegetation can be improved by chemical or percent McMullin soil. The components of this unit occur mechanical treatment. The use of ground equipment is not as areas so intricately intermingled that mapping them practical because of stones on the surface and the slope. separately was not practical at the scale used. This unit is poorly suited to range seeding. The main Included in this unit are small areas of Rock outcrop; limitations are the slope, droughtiness, the depth to Carney and Medco soils on concave slopes and on the less bedrock in the McMullin soil, and the clayey surface layer sloping parts of the landscape; Skookum and Tablerock of the Heppsie soil. The plants selected for seeding should soils; and, on ridges and convex slopes, soils that are be those that meet the seasonal requirements of livestock similar to the Heppsie soil but have bedrock within a depth or wildlife, or both. of 20 inches. Also included are small areas of Heppsie soils The slope limits access by livestock and results in that have slopes of less than 35 or more than 70 percent. overgrazing of the less sloping areas. Constructing trails or Included areas make up about 20 percent of the total walkways allows livestock to graze in areas where access is acreage. limited. The Heppsie soil is moderately deep and well drained. It formed in colluvium derived dominantly from This unit is limited as a site for livestock watering mortality. Also, the bedrock restricts root growth. As a ponds and other water impoundments because of the result, windthrow is a hazard. slope of both soils and the depth to bedrock in the Wheeled and tracked logging equipment can be used in McMullin soil. the less sloping areas, but cable yarding generally is safer in The vegetative site in areas of the Heppsie soil is the more sloping areas and results in less surface Loamy Hills, 20- to 35-inch precipitation zone, and the disturbance. Using standard wheeled and tracked one in areas of the McMullin soil is Shallow Mountain equipment when the soil is moist causes rutting and Slopes, 22- to 30-inch precipitation zone. compaction. Displacement of the surface layer occurs most readily when the soil is dry. Puddling can occur when the 83E-Hobit loam, 12 to 35 percent north slopes. soil is wet. Using low-pressure ground equipment causes This moderately deep, well drained soil is on hillslopes. It less damage to the soil and helps to maintain productivity. formed in colluvium derived dominantly from andesite, tuff, Compaction can be minimized by using suitable methods of and breccia. Elevation is 5,000 to 6,000 feet. The mean harvesting, laying out skid trails in advance, and harvesting annual precipitation is 30 to 50 inches, the mean annual timber when the soil is least susceptible to compaction. temperature is 40 to 44 degrees F, and the average Ripping skid trails and landings when the soil is dry can frost-free period is less than 100 days. The native improve the growth of plants. vegetation is mainly conifers and an understory of grasses, Properly designed road drainage systems that include shrubs, and forbs. carefully located culverts help to control erosion. Areas that Typically, the surface is covered with a layer of needles have been cut and filled are easily eroded unless they are and twigs about 1 inch thick. The surface layer is very dark treated. Seeding, mulching, and benching these areas help brown loam about 18 inches thick. The subsoil also is very to control erosion. Steep yarding paths, skid trails, and dark brown loam. It is about 8 inches thick. The substratum firebreaks are subject to rilling and gullying unless they are is dark yellowish brown gravelly clay loam about 9 inches protected by a plant cover or adequate water bars, or both. thick. Weathered bedrock is at a depth of about 35 inches. Skid trails and unsurfaced roads may be impassable during The depth to bedrock ranges from 20 to 40 inches. In some rainy periods. Logging roads require suitable surfacing for areas the surface layer is stony. year-round use. Included in this unit are small areas of Tatouche soils, Undesirable plants limit natural or artificial reforestation Bybee soils on concave slopes and on the less sloping parts unless intensive site preparation and maintenance of the landscape, soils that are similar to the Hobit soil but measures are applied. Reforestation can be accomplished have bedrock at a depth of less than 20 or more than 40 by planting ponderosa pine and white fir seedlings. inches or have more than 35 percent rock fragments, and Mulching around seedlings helps to maintain the moisture poorly drained soils near drainageways and on concave supply in summer and minimizes competition from slopes. Also included are small areas of Hobit soils that undesirable understory plants. have slopes of less than 12 or more than 35 percent. Severe frost can damage or kill seedlings. In the less Included areas make up about 20 percent of the total sloping areas where air drainage may be restricted, proper acreage. timber harvesting methods can reduce the effect of frost on Permeability is moderate in the Hobit soil. Available regeneration. water capacity is about 7 inches. The effective rooting The main limitations affecting livestock grazing are depth is 20 to 40 inches. Runoff is medium, and the compaction and erosion. The native vegetation suitable for hazard of water erosion is moderate. grazing includes Canada bluegrass, Alaska oniongrass, This unit is used for timber production, livestock and mountain brome. If the understory is overgrazed, the grazing, and wildlife habitat. proportion of preferred forage plants decreases and the This unit is suited to the production of white fir. Other proportion of less preferred forage plants increases. species that grow on this unit include Douglas fir, incense A planned grazing system that includes timely deferment cedar, and Rocky Mountain maple. The understory of grazing, rotation grazing, and proper livestock distribution vegetation includes cascade Oregongrape, common helps to prevent overgrazing of the understory and damage snowberry, and gooseberry. to the soil. Grazing should be delayed until the more On the basis of a 50-year site curve, the mean site desirable forage plants have achieved enough growth to index for white fir is 70. The yield at culmination of the withstand grazing pressure and the soil is firm enough to mean annual increment is 11,410 cubic feet per acre in a withstand trampling by livestock. fully stocked, even-aged stand of trees at 70 years. The main limitations affecting timber production are erosion, compaction, plant competition, and seedling Thinning, logging, and fire reduce the density of the The main limitations affecting timber production are the overstory canopy and increase the production of slope, erosion, compaction, plant competition, and understory vegetation. Areas that support a large amount seedling mortality. Also, the bedrock restricts root growth. of competing vegetation can be improved by prescribed As a result, windthrow is a hazard. burning or by chemical or mechanical treatment. Seeding Wheeled and tracked logging equipment can be used in disturbed areas to suitable plants increases forage the less sloping areas, but cable yarding generally is safer production and reduces the risk of erosion. The seedling and results in less surface disturbance. Using standard survival rate may be low, however, because of cold wheeled and tracked equipment when the soil is moist temperatures in spring. causes rutting and compaction. Displacement of the surface The vegetative site is White Fir Forest. layer occurs most readily when the soil is dry. Puddling can occur when the soil is wet. Using low-pressure ground 83G-Hobit loam, 35 to 60 percent north slopes. equipment causes less damage to the soil and helps to This moderately deep, well drained soil is on hillslopes. It maintain productivity. Compaction can be minimized by formed in colluvium derived dominantly from andesite, tuff, using suitable methods of harvesting, laying out skid trails in and breccia. Elevation is 5,000 to 6,000 feet. The mean advance, and harvesting timber when the soil is least annual precipitation is 30 to 50 inches, the mean annual susceptible to compaction. Ripping skid trails and landings temperature is 40 to 44 degrees F, and the average when the soil is dry can improve the growth of plants. frost-free period is less than 100 days. The native Properly designed road drainage systems that include vegetation is mainly conifers and an understory of grasses, carefully located culverts help to control erosion. Areas that shrubs, and forbs. have been cut and filled are easily eroded unless they are Typically, the surface is covered with a layer of needles treated. Seeding, mulching, and benching these areas help and twigs about 1 inch thick. The surface layer is very dark to control erosion. Steep yarding paths, skid trails, and brown loam about 18 inches thick. The subsoil also is very firebreaks are subject to rilling and gullying unless they are dark brown loam. It is about 8 inches thick. The substratum protected by a plant cover or adequate water bars, or both. is dark yellowish brown gravelly clay loam about 9 inches Cutbanks occasionally slump when the soil is saturated. thick. Weathered bedrock is at a depth of about 35 inches. Constructing logging roads on the steeper slopes can The depth to bedrock ranges from 20 to 40 inches. In some result in a high risk of erosion. Building the roads at areas the surface layer is stony. midslope requires extensive cutting and filling and removes Included in this unit are small areas of Tatouche soils, land from production. Material that is discarded when the Woodseye soils and Rock outcrop on ridges and convex roads are built can damage vegetation and is a potential slopes, soils that are similar to the Hobit soil but have source of sedimentation. If the material becomes saturated, bedrock at a depth of less than 20 or more than 40 inches avalanches of debris can occur. End hauling of the waste or have more than 35 percent rock fragments, and poorly material minimizes damage to the vegetation downslope drained soils near drainageways and on concave slopes. and reduces the risk of sedimentation. Skid trails and Also, included are small areas of Hobit soils that have unsurfaced roads may be impassable during rainy periods. slopes of less than 35 or more than 60 percent. Included Logging roads require suitable surfacing for year-round use. areas make up about 20 percent of the total acreage. Undesirable plants limit natural or artificial reforestation Permeability is moderate in the Hobit soil. Available unless intensive site preparation and maintenance water capacity is about 7 inches. The effective rooting measures are applied. Reforestation can be accomplished depth is 20 to 40 inches. Runoff is rapid, and the hazard by planting ponderosa pine and white fir seedlings. of water erosion is high. Mulching around seedlings helps to maintain the moisture This unit is used for timber production, livestock supply in summer and minimizes competition from grazing, and wildlife habitat. undesirable understory plants. This unit is suited to the production of white fir. Other Severe frost can damage or kill seedlings. Proper timber species that grow on this unit include Douglas fir, incense harvesting methods can reduce the effect of frost on cedar, and Rocky Mountain maple. The understory regeneration. vegetation includes cascade Oregongrape, common The main limitations affecting livestock grazing are snowberry, and gooseberry. erosion, compaction, and the slope. The native vegetation On the basis of a 50-year site curve, the mean site suitable for grazing includes Canada bluegrass, Alaska index for white fir is 70. The yield at culmination of the oniongrass, and mountain brome. If the understory is mean annual increment is 11,410 cubic feet per acre in a overgrazed, the proportion of preferred fully stocked, even-aged stand of trees at 70 years. forage plants decreases and the proportion of less This unit is used for timber production, livestock preferred forage plants increases. grazing, and wildlife habitat. A planned grazing system that includes timely deferment This unit is suited to the production of white fir and of grazing, rotation grazing, and proper livestock distribution Douglas fir. Other species that grow on this unit include helps to prevent overgrazing of the understory and damage incense cedar. The understory vegetation includes Pacific to the soil. Grazing should be delayed until the more serviceberry, tall Oregongrape, and common snowberry. desirable forage plants have achieved enough growth to On the basis of a 50-year site curve, the mean site index withstand grazing pressure and the soil is firm enough to for white fir is 65. The yield at culmination of the mean withstand trampling by livestock. annual increment is 10,150 cubic feet per acre in a fully Thinning, logging, and fire reduce the density of the stocked, even-aged stand of trees at 70 years. overstory canopy and increase the production of The main limitations affecting timber production are understory vegetation. Areas that support a large amount erosion, compaction, seedling mortality, and plant of competing vegetation can be improved by prescribed competition. Also, the bedrock restricts root growth. As a burning or by chemical or mechanical treatment. Seeding result, windthrow is a hazard. disturbed areas to suitable plants increases forage Wheeled and tracked logging equipment can be used in production and reduces the risk of erosion. The seedling the less sloping areas, but cable yarding generally is safer survival rate may be low, however, because of cold in the more sloping areas and results in less surface temperatures in spring. disturbance. Using standard wheeled and tracked The vegetative site is White Fir Forest. equipment when the soil is moist causes rutting and compaction. Displacement of the surface layer occurs most 84E-Hobit loam, 12 to 35 percent south slopes. readily when the soil is dry. Puddling can occur when the This moderately deep, well drained soil is on hillslopes. It soil is wet. Using low-pressure ground equipment causes formed in colluvium derived dominantly from andesite, tuff, less damage to the soil and helps to maintain productivity. and breccia. Elevation is 5,000 to 6,000 feet. The mean Compaction can be minimized by using suitable methods of annual precipitation is 30 to 50 inches, the mean annual harvesting, laying out skid trails in advance, and harvesting temperature is 40 to 44 degrees F, and the average timber when the soil is least susceptible to compaction. frost-free period is less than 100 days. The native Ripping skid trails and landings when the soil is dry can vegetation is mainly conifers and an understory of grasses, improve the growth of plants. shrubs, and forbs. Properly designed road drainage systems that include Typically, the surface is covered with a layer of needles carefully located culverts help to control erosion. Areas that and twigs about 1 inch thick. The surface layer is very dark have been cut and filled are easily eroded unless they are brown loam about 18 inches thick. The subsoil also is very treated. Seeding, mulching, and benching these areas help dark brown loam. It is about 8 inches thick. The substratum to control erosion. Steep yarding paths, skid trails, and is dark yellowish brown gravelly clay loam about 9 inches firebreaks are subject to rilling and gullying unless they are thick. Weathered bedrock is at a depth of about 35 inches. protected by a plant cover or adequate water bars, or both. The depth to bedrock ranges from 20 to 40 inches. In some Skid trails and unsurfaced roads may be impassable during areas the surface layer is stony. rainy periods. Logging roads require suitable surfacing for Included in this unit are small areas of Tatouche soils, year-round use. Bybee soils on concave slopes and on the less sloping parts A high temperature in the surface layer and an of the landscape, soils that are similar to the Hobit soil but insufficient moisture supply in summer increase the have bedrock at a depth of less than 20 or more than 40 seedling mortality rate. To compensate for the expected inches, poorly drained soils near drainageways and on high mortality rate, the larger seedlings or a greater number concave slopes, and soils that are similar to the Hobit soil of seedlings should be planted. When the timber is but have more than 35 percent rock fragments. Also harvested, leaving some of the larger trees unharvested included are small areas of Hobit soils that have slopes of provides shade for seedlings. Reforestation can be less than 12 or more than 35 percent. Included areas make accomplished by planting Douglas fir and ponderosa pine up about 20 percent of the total acreage. seedlings. Permeability is moderate in the Hobit soil. Available Severe frost can damage or kill seedlings. In the less water capacity is about 7 inches. The effective rooting sloping areas where air drainage may be restricted, proper depth is 20 to 40 inches. Runoff is medium, and the timber harvesting methods can reduce the effect of frost on hazard of water erosion is moderate. regeneration. Undesirable plants limit natural or artificial reforestation fragments, and poorly drained soils near drainageways and unless intensive site preparation and maintenance on concave slopes. Also included are small areas of Hobit measures are applied. Mulching around seedlings helps soils that have slopes of less than 35 or more than 60 to maintain the moisture supply in summer and minimizes percent. Included areas make up about 20 percent of the competition from undesirable understory plants. total acreage. The main limitations affecting livestock grazing are Permeability is moderate in the Hobit soil. Available compaction and erosion. The native vegetation suitable for water capacity is about 7 inches. The effective rooting grazing includes western fescue, mountain brome, tall depth is 20 to 40 inches. Runoff is rapid, and the hazard of trisetum, and Alaska oniongrass. If the understory is water erosion is high. overgrazed, the proportion of preferred forage plants This unit is used for timber production, livestock decreases and the proportion of less preferred forage plants grazing, and wildlife habitat. increases. This unit is suited to the production of white fir and A planned grazing system that includes timely deferment Douglas fir. Other species that grow on this unit include of grazing, rotation grazing, and proper livestock distribution incense cedar. The understory vegetation includes Pacific helps to prevent overgrazing of the understory and damage serviceberry, tall Oregongrape, and common snowberry. to the soil. Grazing should be delayed until the more On the basis of a 50-year site curve, the mean site index desirable forage plants have achieved enough growth to for white fir is 65. The yield at culmination of the mean withstand grazing pressure and the soil is firm enough to annual increment is 10,150 cubic feet per acre in a fully withstand trampling by livestock. stocked, even-aged stand of trees at 70 years. Thinning, logging, and fire reduce the density of the The main limitations affecting timber production are the overstory canopy and increase the production of slope, erosion, compaction, seedling mortality, and plant understory vegetation. Areas that support a large amount competition. Also, the bedrock restricts root growth. As a of competing vegetation can be improved by prescribed result, windthrow is a hazard. burning or by chemical or mechanical treatment. Seeding Wheeled and tracked logging equipment can be used in disturbed areas to suitable plants increases forage the less sloping areas, but cable yarding generally is safer production and reduces the risk of erosion. and results in less surface disturbance. Using standard The vegetative site is Mixed Fir-Serviceberry Forest. wheeled and tracked equipment when the soil is moist causes rutting and compaction. Displacement of the surface 84G-Hobit loam, 35 to 60 percent south slopes. layer occurs most readily when the soil is dry. Puddling can This moderately deep, well drained soil is on hillslopes. It occur when the soil is wet. Using low-pressure ground formed in colluvium derived dominantly from andesite, tuff, equipment causes less damage to the soil and helps to and breccia. Elevation is 5,000 to 6,000 feet. The mean maintain productivity. Compaction can be minimized by using annual precipitation is 30 to 50 inches, the mean annual suitable methods of harvesting, laying out skid trails in temperature is 40 to 44 degrees F, and the average advance, and harvesting timber when the soil is least frost-free period is less than 100 days. The native vegetation susceptible to compaction. Ripping skid trails and landings is mainly conifers and an understory of grasses, shrubs, and when the soil is dry can improve the growth of plants. forbs. Properly designed road drainage systems that include Typically, the surface is covered with a layer of needles carefully located culverts help to control erosion. Areas that and twigs about 1 inch thick. The surface layer is very dark have been cut and filled are easily eroded unless they are brown loam about 18 inches thick. The subsoil also is very treated. Seeding, mulching, and benching these areas help dark brown loam. It is about 8 inches thick. The substratum to control erosion. Steep yarding paths, skid trails, and is dark yellowish brown gravelly clay loam about 9 inches firebreaks are subject to rilling and gullying unless they are thick. Weathered bedrock is at a depth of about 35 inches. protected by a plant cover or adequate water bars, or both. The depth to bedrock ranges from 20 to 40 inches. In some Cutbanks occasionally slump when the soil is saturated. areas the surface layer is stony. Constructing logging roads on the steeper slopes can Included in this unit are. small areas of Tatouche soils, result in a high risk of erosion. Building the roads at midslope Woodseye soils and Rock outcrop on ridges and convex requires extensive cutting and filling and removes land from slopes, soils that are similar to the Hobit soil but have production. Material that is discarded when the roads are bedrock at a depth of less than 20 or more than 40 inches or built can damage vegetation and is a potential source of have more than 35 percent rock sedimentation. If the material becomes saturated, avalanches of debris can occur. End hauling of the waste material minimizes temperature is 40 to 45 degrees F, and the average damage to the vegetation downslope and reduces the risk frost-free period is less than 100 days. The native of sedimentation. Skid trails and unsurfaced roads may be vegetation is mainly grasses, sedges, and forbs. impassable during rainy periods. Logging roads require Typically, the surface layer is black silt loam about 10 suitable surfacing for year-round use. inches thick. The next 4 inches also is black silt loam. The A high temperature in the surface layer and an upper 14 inches of the subsoil is grayish brown silt loam. insufficient moisture supply in summer increase the The lower 16 inches is grayish brown very fine sandy loam seedling mortality rate. To compensate for the expected and silt loam. The substratum to a depth of 65 inches is high mortality rate, the larger seedlings or a greater number grayish brown silt loam. The depth to bedrock is 60 inches of seedlings should be planted. When the timber is or more. In some areas the surface layer is stony or cobbly. harvested, leaving some of the larger trees unharvested Included in this unit are small areas of Kanutchan soils; provides shade for seedlings. The seedling mortality rate very poorly drained, organic soils; and soils that are also can be reduced by providing artificial shade for similar to the Hoxie soil but have a subsoil of clay. seedlings. Reforestation can be accomplished by planting Included areas make up about 10 percent of the total Douglas fir and ponderosa pine seedlings. acreage. Severe frost can damage or kill seedlings. Proper timber Permeability is moderate in the Hoxie soil. Available harvesting methods can reduce the effect of frost on water capacity is about 13 inches. The effective rooting regeneration. depth is limited by the water table, which is within a depth Undesirable plants limit natural or artificial of 3 feet from March through June. Runoff is slow, and the reforestation unless intensive site preparation and hazard of water erosion is slight. maintenance measures are applied. Mulching around This unit is used for pasture and wildlife habitat. The seedlings helps to maintain the moisture supply in main limitations affecting livestock grazing are the seasonal summer and minimizes competition from undesirable wetness, a short growing season, and compaction. The understory plants. wetness limits the choice of suitable forage plants and the The main limitations affecting livestock grazing are period of cutting or grazing and increases the risk of erosion, compaction, and the slope. The native vegetation winterkill. suitable for grazing includes western fescue, mountain If the pasture is overgrazed, the proportion of preferred brome, tall trisetum, and Alaska oniongrass. If the forage plants decreases and the proportion of less understory is overgrazed, the proportion of preferred forage preferred forage plants increases. The grazing system plants decreases and the proportion of less preferred forage should maintain the desired balance of species in the plant plants increases. community. Proper stocking rates, pasture rotation, and A planned grazing system that includes timely deferment restricted grazing during wet periods help to keep pastures of grazing, rotation grazing, and proper livestock distribution in good condition and protect the soil from erosion. Grazing helps to prevent overgrazing of the understory and damage when the soil is wet results in compaction of the surface to the soil. Grazing should be delayed until the more layer, poor tilth, and excessive runoff. Periodic mowing and desirable forage plants have achieved enough growth to clipping help to maintain uniform plant growth, discourage withstand grazing pressure and the soil is firm enough to selective grazing, and reduce the extent of clumpy growth. withstand trampling by livestock. Tufted hairgrass is the native plant preferred for Thinning, logging, and fire reduce the density of the livestock grazing; however, this unit can be renovated and overstory canopy and increase the production of forage production increased by seeding other suitable understory vegetation. Areas that support a large amount grasses. The plants selected for seeding should be those of competing vegetation can be improved by prescribed that are tolerant of a cold climate and wetness. Border and burning or by chemical or mechanical treatment. Seeding contour flood irrigation systems are suitable. Land leveling disturbed areas to suitable plants increases forage helps to ensure a uniform application of water. Fertilizer is production and reduces the risk of erosion. needed to ensure the optimum growth of grasses. The vegetative site is Mixed Fir-Serviceberry Forest. Grasses respond to nitrogen. The vegetative site is Wet Meadow. 85A-Hoxie silt loam, 0 to 1 percent slopes. This very deep, poorly drained soil is in basins. It formed in lacustrine sediment derived dominantly from volcanic ash. 86C-Hukill gravelly loam, 1 to 12 percent slopes. Elevation is 4,300 to 5,000 feet. The mean annual This deep, well drained soil is on plateaus. It formed in precipitation is 30 to 40 inches, the mean annual residuum and colluvium derived from andesite. Elevation is 2,000 to 3,000 feet. The mean annual landings when the soil is dry can improve the growth of precipitation is 30 to 45 inches, the mean annual plants. temperature is 45 to 52 degrees F, and the average Erosion can be controlled by carefully planning the frost-free period is 100 to 150 days. The native construction and maintenance of logging roads, skid trails, vegetation is mainly conifers and hardwoods and an and landings. Seeding, mulching, and benching areas that understory of grasses, shrubs, and forbs. have been cut and filled also help to control erosion. Skid Typically, the surface is covered with a layer of needles, trails and unsurfaced roads may be impassable during leaves, and twigs about 1/2 inch thick. The surface layer is rainy periods. Logging roads require suitable surfacing for dark reddish brown gravelly loam about 2 inches thick. The year-round use. next layer is dark reddish brown gravelly clay loam about 4 Undesirable plants limit natural or artificial reforestation inches thick. The upper 5 inches of the subsoil also is dark unless intensive site preparation and maintenance reddish brown gravelly clay loam. The lower 31 inches is measures are applied. Reforestation can be accomplished dark reddish brown gravelly clay. Weathered bedrock is at a by planting Douglas fir and ponderosa pine seedlings. depth of about 42 inches. The depth to bedrock ranges from Mulching around seedlings helps to maintain the moisture 40 to 60 inches. In some areas the surface layer is stony. supply in summer and minimizes competition from Included in this unit are small areas of Freezener soils, undesirable understory plants. Terrabella soils near drainageways and on concave slopes, Severe frost can damage or kill seedlings. Air Geppert soils on convex slopes and on the more sloping drainage may be restricted on this unit. Proper timber parts of the landscape, and soils that are similar to the harvesting methods can reduce the effect of frost on Hukill soil but have bedrock within a depth of 40 inches. regeneration. Also included are small areas of Hukill soils that have The main limitation affecting livestock grazing is slopes of more than 12 percent. Included areas make up compaction. The native vegetation suitable for grazing about 15 percent of the total acreage. includes western fescue, mountain brome, tall trisetum, and Permeability is moderately slow in the Hukill soil. Alaska oniongrass. If the understory is overgrazed, the Available water capacity is about 7 inches. The effective proportion of preferred forage plants decreases and the rooting depth is 40 to 60 inches. Runoff is slow, and the proportion of less preferred forage plants increases. hazard of water erosion is slight. A planned grazing system that includes timely deferment This unit is used for timber production, livestock of grazing, rotation grazing, and proper livestock distribution grazing, and wildlife habitat. helps to prevent overgrazing of the understory and damage This unit is suited to the production of Douglas fir. Other to the soil. Grazing should be delayed until the more species that grow on this unit include sugar pine, desirable forage plants have achieved enough growth to ponderosa pine, white fir, and California black oak. The withstand grazing pressure and the soil is firm enough to understory vegetation includes Pacific serviceberry, tall withstand trampling by livestock. Oregongrape, and western fescue. Thinning, logging, and fire reduce the density of the On the basis of a 100-year site curve, the mean site overstory canopy and increase the production of index for Douglas fir is 110. The yield at culmination of the understory vegetation. Areas that support a large amount mean annual increment is 5,880 cubic feet per acre in a of competing vegetation can be improved by prescribed fully stocked, even-aged stand of trees at 60 years and burning or by chemical or mechanical treatment. Seeding 48,300 board feet per acre (Scribner rule) at 140 years. On disturbed areas to suitable plants increases forage the basis of a 50-year curve, the mean site index is 75. production and reduces the risk of erosion. The main limitations affecting timber production are The vegetative site is Mixed Fir-Mixed Pine Forest. compaction, erosion, and plant competition. Conventional methods of harvesting timber generally are suitable, but the 87F-Jayar very gravelly loam, 12 to 45 percent north soil may be compacted if it is moist when heavy equipment slopes. This moderately deep, well drained soil is on is used. Puddling can occur when the soil is wet. Using hillslopes. It formed in colluvium derived dominantly from low-pressure ground equipment causes less damage to the metamorphic rock. Elevation is 3,600 to 5,300 feet. The soil and helps to maintain productivity. Compaction can be mean annual precipitation is 40 to 60 inches, the mean minimized by using suitable methods of harvesting, laying annual temperature is 40 to 45 degrees F, and the average out skid trails in advance, and harvesting timber when the frost-free period is less than 100 days. The native vegetation soil is least susceptible to compaction. Ripping skid trails is mainly conifers and an understory of grasses, shrubs, and and forbs. Typically, the surface is covered with a layer of needles, leaves, and twigs about 1 inch thick. The surface Properly designed road drainage systems that include layer is very dark grayish brown very gravelly loam about 5 carefully located culverts help to control erosion. Road cuts inches thick. The next layer is dark brown very gravelly on this unit expose a large amount of fractured bedrock, loam about 6 inches thick. The subsoil also is dark brown which limits the response to seeding and mulching. Steep very gravelly loam. It is about 13 inches thick. Bedrock is at yarding paths, skid trails, and firebreaks are subject to rilling a depth of about 24 inches. The depth to bedrock ranges and gullying unless they are protected by a plant cover or from 20 to 40 inches. In some areas the surface layer is adequate water bars, or both. Skid trails and unsurfaced stony. roads may be impassable during rainy periods. Logging Included in this unit are small areas of Woodseye soils roads require suitable surfacing for year-round use. and Rock outcrop on ridges and convex slopes and small A high temperature in the surface layer during summer areas of soils that are similar to the Jayar soil but are and the low available water capacity increase the seedling influenced by serpentine, have less than 35 percent rock mortality rate. The large number of rock fragments in the fragments, or have bedrock at a depth of more than 40 soil also increases the seedling mortality rate. To inches. Also included are small areas of Jayar soils that compensate for the expected high mortality rate, the larger have slopes of less than 12 or more than 45 percent. seedlings or a greater number of seedlings should be Included areas make up about 20 percent of the total planted. When the timber is harvested, leaving some of the acreage. larger trees unharvested provides shade for seedlings. Permeability is moderate in the Jayar soil. Available Reforestation can be accomplished by planting Douglas fir water capacity is about 3 inches. The effective rooting seedlings. depth is 20 to 40 inches. Runoff is medium or rapid, and Severe frost can damage or kill seedlings. In the less the hazard of water erosion is moderate or high. sloping areas where air drainage may be restricted, proper This unit is used for timber production and wildlife timber harvesting methods can reduce the effect of frost on habitat. It is suited to the production of Douglas fir and regeneration. white fir. Other species that grow on this unit include Undesirable plants limit natural or artificial incense cedar and ponderosa pine. The understory reforestation unless intensive site preparation and vegetation includes creambush oceanspray, cascade maintenance measures are applied. Mulching around Oregongrape, and whitevein shinleaf. seedlings helps to maintain the moisture supply in On the basis of a 100-year site curve, the mean site summer and minimizes competition from undesirable index for Douglas fir is 100. The yield at culmination of the understory plants. mean annual increment is 5,040 cubic feet per acre in a The vegetative site is Mixed Fir-Oceanspray Forest. fully stocked, even-aged stand of trees at 60 years and 39,750 board feet per acre (Scribner rule) at 150 years. On 87G-Jayar very gravelly loam, 45 to 70 percent north the basis of a 50-year curve, the mean site index is 80 slopes. This moderately deep, well drained soil is on The main limitations affecting timber production are hillslopes. It formed in colluvium derived dominantly from erosion, compaction, seedling mortality, and plant metamorphic rock. Elevation is 3,600 to 5,300 feet. The competition. Also, the bedrock restricts root growth. As a mean annual precipitation is 40 to 60 inches, the mean result, windthrow is a hazard. annual temperature is 40 to 45 degrees F, and the average Wheeled and tracked logging equipment can be used in frost-free period is less than 100 days. The native vegetation the less sloping areas, but cable yarding generally is safer is mainly conifers and an understory of grasses, shrubs, and in the more sloping areas and results in less surface forbs. disturbance. If the soil is excessively disturbed when timber Typically, the surface is covered with a layer of needles, is harvested or logging roads are built, a larger number of leaves, and twigs about 1 inch thick. The surface layer is rock fragments is left on the surface. Using standard very dark grayish brown very gravelly loam about 5 inches wheeled and tracked equipment when the soil is moist thick. The next layer is dark brown very gravelly loam about causes rutting and compaction. Puddling can occur when 6 inches thick. The subsoil also is dark brown very gravelly the soil is wet. Using low-pressure ground equipment loam. It is about 13 inches thick. Bedrock is at a depth of causes less damage to the soil and helps to maintain about 24 inches. The depth to bedrock ranges from 20 to productivity. Compaction can be minimized by using 40 inches. In some areas the surface layer is stony. suitable methods of harvesting, laying out skid trails in Included in this unit are small areas of Woodseye advance, and harvesting timber when the soil is least soils and Rock outcrop on ridges and convex slopes susceptible to compaction. Ripping skid trails and landings and soils that are similar to the Jayar soil but are when the soil is dry can improve the growth of plants. influenced by serpentine, have less than 35 percent rock fragments, or have bedrock at a depth of more than Severe frost can damage or kill seedlings. A high 40 inches. Also included are small areas of Jayar soils that temperature in the surface layer during summer and the low have slopes of less than 45 or more than 70 percent. available water capacity increase the seedling mortality rate. Included areas make up about 20 percent of the total The large number of rock fragments in the soil also acreage. increases the seedling mortality rate. To compensate for the Permeability is moderate in the Jayar soil. Available expected high mortality rate, the larger seedlings or a water capacity is about 3 inches. The effective rooting greater number of seedlings should be planted. When the depth is 20 to 40 inches. Runoff is rapid, and the hazard of timber is harvested, leaving some of the larger trees water erosion is high. unharvested provides shade for seedlings. Reforestation This unit is used for timber production and wildlife can be accomplished by planting Douglas fir seedlings. habitat. It is suited to the production of Douglas fir and Undesirable plants limit natural or artificial white fir. Other species that grow on this unit include reforestation unless intensive site preparation and incense cedar and ponderosa pine. The understory maintenance measures are applied. Mulching around vegetation includes creambush oceanspray, cascade seedlings helps to maintain the moisture supply in Oregongrape, and whitevein shinleaf. summer and minimizes competition from undesirable On the basis of a 100-year site curve, the mean site understory plants. index for Douglas fir is 100. The yield at culmination of the The vegetative site is Mixed Fir-Oceanspray Forest. mean annual increment is 5,040 cubic feet per acre in a fully stocked, even-aged stand of trees at 60 years and 88F-Jayar very gravelly loam, 12 to 45 percent south 39,750 board feet per acre (Scribner rule) at 150 years. On slopes. This moderately deep, well drained soil is on the basis of a 50-year curve, the mean site index is 80. hillslopes. It formed in colluvium derived dominantly from The main limitations affecting timber production are the metamorphic rock. Elevation is 3,600 to 5,300 feet. The slope, erosion, seedling mortality, and plant competition. mean annual precipitation is 40 to 60 inches, the mean Also, the bedrock restricts root growth. As a result, annual temperature is 40 to 45 degrees F, and the average windthrow is a hazard. frost-free period is less than 100 days. The native The slope restricts the use of wheeled and tracked vegetation is mainly conifers and an understory of grasses, logging equipment. High-lead or other cable systems are shrubs, and forbs. the best methods of logging. If the soil is excessively Typically, the surface is covered with a layer of needles, disturbed when timber is harvested or logging roads are leaves, and twigs about 1 inch thick. The surface layer is built, a larger number of rock fragments is left on the very dark grayish brown very gravelly loam about 5 inches surface. Ripping landings when the soil is dry can improve thick. The next layer is dark brown very gravelly loam about the growth of plants. 6 inches thick. The subsoil also is dark brown very gravelly Properly designed road drainage systems that include loam. It is about 13 inches thick. Bedrock is at a depth of carefully located culverts help to control erosion. Road cuts about 24 inches. The depth to bedrock ranges from 20 to can expose a large amount of fractured bedrock, which 40 inches. In some areas the surface layer is stony. limits the response to seeding and mulching. Cut slopes are Included in this unit are small areas of Woodseye soils subject to slumping where the bedrock is highly fractured or and Rock outcrop on ridges and convex slopes and small where rock layers are parallel to the slopes. Steep yarding areas of soils that are similar to the Jayar soil but are paths and firebreaks are subject to rilling and gullying influenced by serpentine, have less than 35 percent rock unless they are protected by a plant cover or adequate fragments, or have bedrock at a depth of more than 40 water bars, or both. inches. Also included are small areas of Jayar soils that Building logging roads at midslope requires extensive have slopes of less than 12 or more than 45 percent. cutting and filling and removes land from production. Included areas make up about 20 percent of the total Material that is discarded when the roads are built can acreage. damage vegetation and is a potential source of Permeability is moderate in the Jayar soil. Available sedimentation. If the material becomes saturated, water capacity is about 3 inches. The effective rooting avalanches of debris can occur. End hauling of the waste depth is 20 to 40 inches. Runoff is medium or rapid, and material minimizes damage to the vegetation downslope the hazard of water erosion is moderate or high. and reduces the risk of sedimentation. Unsurfaced roads This unit is used for timber production and wildlife may be impassable during rainy periods. Logging roads habitat. It is suited to the production of Douglas fir and require suitable surfacing for year-round use. white fir. Other species that grow on this unit include incense cedar and ponderosa pine. The understory vegetation includes Pacific serviceberry, tall proper timber harvesting methods can reduce the effect of Oregongrape, and common snowberry. frost on regeneration. On the basis of a 100-year site curve, the mean site Undesirable plants limit natural or artificial index for Douglas fir is 90. The yield at culmination of the reforestation unless intensive site preparation and mean annual increment is 4,200 cubic feet per acre in a maintenance measures are applied. Mulching around fully stocked, even-aged stand of trees at 60 years and seedlings helps to maintain the moisture supply in 31,840 board feet per acre (Scribner rule) at 160 years. On summer and minimizes competition from undesirable the basis of a 50-year curve, the mean site index is 70. understory plants. The main limitations affecting timber production are The vegetative site is Mixed Fir-Serviceberry Forest. erosion, compaction, seedling mortality, and plant competition. Also, the bedrock restricts root growth. As a 89E-Jayar Variant very gravelly loam, 5 to 35 percent result, windthrow is a hazard. slopes. This moderately deep, well drained soil is on ridges Wheeled and tracked logging equipment can be used in and hillslopes. It formed in colluvium derived dominantly the less sloping areas, but cable yarding generally is safer from metamorphic rock. Elevation is 4,700 to 5,300 feet. in the more sloping areas and results in less surface The mean annual precipitation is 50 to 60 inches, the mean disturbance. If the soil is excessively disturbed when timber annual temperature is 40 to 44 degrees F, and the average is harvested or logging roads are built, a larger number of frost-free period is less than 100 days. The native rock fragments is left on the surface. Using standard vegetation is mainly conifers and an understory of grasses, wheeled and tracked equipment when the soil is moist shrubs, and (orbs. causes rutting and compaction. Puddling can occur when Typically, the surface layer is very dark brown and dark the soil is wet. Using low-pressure ground equipment brown very gravelly loam about 8 inches thick. The subsoil causes less damage to the soil and helps to maintain is dark yellowish brown very cobbly loam about 16 inches productivity. Compaction can be minimized by using thick. Bedrock is at a depth of about 24 inches. The depth to suitable methods of harvesting, laying out skid trails in bedrock ranges from 20 to 40 inches. In some areas the advance, and harvesting timber when the soil is least surface layer is stony. susceptible to compaction. Ripping skid trails and landings Included in this unit are small areas of Woodseye soils when the soil is dry can improve the growth of plants. and Rock outcrop on convex slopes and small areas of Properly designed road drainage systems that include soils that are similar to the Jayar Variant soil but are carefully located culverts help to control erosion. Road cuts influenced by serpentine, have less than 35 percent rock on this unit expose a large amount of fractured bedrock, fragments, or have bedrock at a depth of more than 40 which limits the response to seeding and mulching. Steep inches. Also included are small areas of Jayar Variant yarding paths, skid trails, and firebreaks are subject to rilling soils that have slopes of less than 5 or more than 35 and gullying unless they are protected by a plant cover or percent. Included areas make up about 20 percent of the adequate water bars, or both. Skid trails and unsurfaced total acreage. roads may be impassable during rainy periods. Logging Permeability is moderate in the Jayar Variant soil. roads require suitable surfacing for year-round use. Available water capacity is about 2 inches. The effective A high temperature in the surface layer during summer rooting depth is 20 to 40 inches. Runoff is medium, and the and the low available water capacity increase the seedling hazard of water erosion is moderate. mortality rate. The large number of rock fragments in the This unit is used for timber production and wildlife soil also increases the seedling mortality rate. To habitat. It is suited to the production of white fir and compensate for the expected high mortality rate, the larger noble fir. Other species that grow on this unit include seedlings or a greater, number of seedlings should be incense cedar and Douglas fir. The understory planted. When the timber is harvested, leaving some of the vegetation includes sierra chinkapin, currant, and larger trees unharvested provides shade for seedlings. The pinemat manzanita. seedling mortality rate also can be reduced by providing On the basis of a 50-year site curve, the mean site index artificial shade for seedlings. Reforestation can be for white fir is 50. The yield at culmination of the mean accomplished by planting Douglas fir seedlings. annual increment is 6,370 cubic feet per acre in a fully Severe frost can damage or kill seedlings. In the less stocked, even-aged stand of trees at 70 years and 58,200 sloping areas where air drainage may be restricted, board feet per acre (Scribner rule) at 120 years. The main limitations affecting timber production are erosion, compaction, seedling mortality, and plant competition. Also, the bedrock restricts root growth. As a result, windthrow is a hazard. Wheeled and tracked logging equipment can be used in the less sloping areas, but cable yarding generally is temperature is 45 to 52 degrees F, and the average safer in the more sloping areas and results in less surface frost-free period is 100 to 160 days. The native. disturbance. If the soil is excessively disturbed when timber vegetation is mainly conifers and hardwoods and an is harvested or logging roads are built, a larger number of understory of grasses, shrubs, and forbs. rock fragments is left on the surface. Using standard This unit is about 45 percent Josephine toil and 40 wheeled and tracked equipment when the soil is moist percent Pollard soil. The components of this unit occur as causes rutting and compaction. Puddling can occur when areas so intricately intermingled that mapping them the soil is wet. Using low-pressure ground equipment separately was not practical at the scale used. causes less damage to the soil and helps to maintain Included in this unit are small areas of Dubakella, productivity. Compaction can be minimized by using Goolaway, Siskiyou, Speaker, and Wolfpeak soils; Abegg suitable methods of harvesting, laying out skid trails in soils on alluvial fans and along drainageways; Beekman advance, and harvesting timber when the soil is least soils on the more sloping parts of the landscape and on susceptible to compaction. Ripping skid trails and landings convex slopes; poorly drained soils near drainageways and when the soil is dry can improve the growth of plants. on concave slopes; and soils that are similar to the Josephine and Pollard soils but have more than 35 percent Properly designed road drainage systems that include rock fragments. Also included are small areas of Josephine carefully located culverts help to control erosion. Road cuts and Pollard soils that have slopes of less than 12 or more can expose a large amount of fractured bedrock, which than 35 percent. Included areas make up about 15 percent limits the response to seeding and mulching. Steep yarding of the total acreage. paths, skid trails, and firebreaks are subject to rilling and The Josephine soil is deep and well drained. It formed in gullying unless they are protected by a plant cover or colluvium and residuum derived dominantly from adequate water bars, or both. Skid trails and unsurfaced metamorphic rock. Typically, the surface is covered with a roads maybe impassable during rainy periods. Logging layer of needles, leaves, and twigs about 1 inch thick. The roads require suitable surfacing for year-round use. surface layer is dark reddish brown gravelly loam about 15 Severe frost can damage or kill seedlings. Seedling inches thick. The subsoil is dark reddish brown and reddish mortality is higher on ridgetops, which are more exposed brown gravelly clay loam about 40 inches thick. Weathered to cold winds than other parts of the landscape. Proper bedrock is at a depth of about 55 inches. The depth to timber harvesting methods can reduce the effect of frost bedrock ranges from 40 to 60 inches. In some areas the on regeneration. surface layer is clay loam. A high temperature in the surface layer during summer Permeability is moderately slow in the Josephine soil. and the low available water capacity increase the seedling Available water capacity is about 7 inches. The effective mortality rate. The large number of rock fragments in the rooting depth is 40 to 60 inches. Runoff is medium, and the soil also increases the seedling mortality rate. To hazard of water erosion is moderate. compensate for the expected high mortality rate, the larger The Pollard soil is very deep and well drained. It formed seedlings or a greater number of seedlings should be in alluvium and colluvium derived dominantly from planted. When the timber is harvested, leaving some of the metamorphic rock. Typically, the surface is covered with a larger trees unharvested provides shade for seedlings. layer of needles, leaves, and twigs about 2 inches thick. The Reforestation can be accomplished by planting Douglas fir surface layer is dark brown loam about 11 inches thick. The and ponderosa pine seedlings. upper 25 inches of the subsoil is dark reddish brown clay Undesirable plants limit natural or artificial loam. The lower 25 inches is yellowish red and brown clay reforestation unless intensive site preparation and loam. The depth to bedrock is 60 inches or more. In some maintenance measures are applied. Mulching around areas the surface layer is clay loam or gravelly foam. seedlings helps to maintain the moisture supply in Permeability is slow in the Pollard soil. Available water summer and minimizes competition from undesirable capacity is about 7 inches. The effective rooting depth is understory plants. 60 inches or more. Runoff is medium, and the hazard of The vegetative site is Noble Fir-Bush Chinkapin water erosion is moderate. Forest. This unit is used for timber production and wildlife habitat. It is suited to the production of Douglas fir. Other 90E-Josephine -pollard complex, 12 to 35 percent species that grow on this unit include ponderosa pine, north slopes. This map unit is on hillslopes and alluvial incense cedar, and golden chinkapin. The understory fans. Elevation is 1,200 to 4,000 feet. The mean annual vegetation includes creambush oceanspray, precipitation is 40 to 50 inches, the mean annual cascade Oregongrape, and deerfoot vanillaleaf. This unit is about 55 percent Josephine soil and 30 On the basis of a 100-year site curve, the mean site percent Pollard soil. The components of this unit occur as index for Douglas fir is 130 on both the Josephine and areas so intricately intermingled that mapping them Pollard soils. The yield at culmination of the mean annual separately was not practical at the scale used. increment is 7,740 cubic feet per acre in a fully stocked, Included in this unit are small areas of Abegg soils on even-aged stand of trees at 60 years and 58,520 board feet alluvial fans and near drainageways; Beekman soils on the per acre (Scribner rule) at 110 years. On the basis of a more sloping parts of the landscape and on convex slopes; 50-year curve, the mean site index is 95. poorly drained soils near drainageways and on concave The main limitations affecting timber production are slopes; Dubakella, Goolaway, Speaker, and Wolfpeak soils; erosion, compaction, slumping, and plant competition. Using and soils that are similar to the Josephine and Pollard soils standard wheeled and tracked equipment when the soils are but have more than 35 percent rock fragments. Also moist causes rutting and compaction. Puddling can occur included are small areas of Josephine and Pollard soils that when the soils are wet. Using low-pressure ground have slopes of less than 12 or more than 35 percent. equipment causes less damage to the soils and helps to Included areas make up about 15 percent of the total maintain productivity. Compaction can be minimized by acreage. using suitable methods of harvesting, laying out skid trails in The Josephine soil is deep and well drained. It formed in advance, and harvesting timber when the soils are least colluvium and residuum derived dominantly from susceptible to compaction. Ripping skid trails and landings metamorphic rock. Typically, the surface is covered with a when the soils are dry can improve the growth of plants. layer of needles, leaves, and twigs about 1 inch thick. The Properly designed road drainage systems that include surface layer is dark reddish brown gravelly loam about 15 carefully located culverts help to control erosion. Seeding, inches thick. The subsoil is dark reddish brown and reddish mulching, and benching areas that have been cut and filled brown gravelly clay loam about 40 inches thick. Weathered also help to control erosion. Steep yarding paths, skid trails, bedrock is at a depth of about 55 inches. The depth to and firebreaks are subject to rilling and gullying unless they bedrock ranges from 40 to 60 inches. In some areas the are protected by a plant cover or adequate water bars, or surface layer is clay loam. both. Permeability is moderately slow in the Josephine soil. The Pollard soil is subject to slumping. Road failure and Available water capacity is about 7 inches. The effective landslides are likely to occur after road construction and rooting depth is 40 to 60 inches. Runoff is medium, and the clearcutting. Slumping can be minimized by constructing hazard of water erosion is moderate. logging roads in the less sloping areas, on better suited The Pollard soil is very deep and well drained. It formed soils if practical, and by installing properly designed road in alluvium and colluvium derived dominantly from drainage systems. Skid trails and unsurfaced roads may be metamorphic rock. Typically, the surface is covered with a impassable during rainy periods. Logging roads require layer of needles, leaves, and twigs about 2 inches thick. The suitable surfacing for year-round use. surface layer is dark brown loam about 11 inches thick. The Undesirable plants limit natural or artificial reforestation upper 25 inches of the subsoil is dark reddish brown clay unless intensive site preparation and maintenance loam. The lower 25 inches is yellowish red and brown clay measures are applied. Reforestation can be loam. The depth to bedrock is 60 inches or more. In some accomplished by planting Douglas fir seedlings. Mulching areas the surface layer is clay loam or gravelly loam. around seedlings helps to maintain the moisture supply in Permeability is slow in the Pollard soil. Available water summer and minimizes competition from undesirable capacity is about 7 inches. The effective rooting depth is understory plants. 60 inches or more. Runoff is medium, and the hazard of The vegetative site is Douglas Fir-Chinkapin Forest. water erosion is moderate. This unit is used for timber production and wildlife 91E-Josephine -Pollard complex, 12 to 35 percent habitat. It is suited to the production of Douglas fir and south slopes. This map unit is on hillslopes and alluvial ponderosa pine. Other species that grow on this unit fans. Elevation is 1,200 to 4,000 feet. The mean annual include sugar pine and California black oak. The precipitation is 40 to 50 inches, the mean annual understory vegetation includes canyon live oak, temperature is 45 to 52 degrees F, and the average deerbrush, and western fescue. frost-free period is 100 to 160 days. The native vegetation is On the basis of a 100-year site curve, the mean site mainly conifers and hardwoods and an understory of index for Douglas fir is 120 on the Josephine soil. The yield grasses, shrubs, and forbs. at culmination of the mean annual increment is 6,900 cubic feet per acre in a fully stocked, even-aged stand of trees at 60 years and 52,440 board feet per acre timber is harvested, leaving some of the larger trees (Scribner rule) at 120 years. On the basis of a 50-year unharvested provides shade for seedlings. The seedling curve, the mean site index is 90. mortality rate also can be reduced by providing artificial On the basis of a 100-year site curve, the mean site shade for seedlings. Reforestation can be accomplished by index for Douglas fir is 125 on the Pollard soil. The yield at planting Douglas fir and ponderosa pine seedlings. culmination of the mean annual increment is 7,320 cubic Undesirable plants limit natural or artificial feet per acre in a fully stocked, even-aged stand of trees at reforestation unless intensive site preparation and 60 years and 58,200 board feet per acre (Scribner rule) at maintenance measures are applied. Mulching around 120 years. On the basis of a 50-year curve, the mean site seedlings helps to maintain the moisture supply in index is 90. summer and minimizes competition from undesirable On the basis of a 100-year site curve, the mean site understory plants. index for ponderosa pine is 115 on both the Josephine and The vegetative site is Douglas Fir-Black Oak Forest. Pollard soils. The yield at culmination of the mean annual increment is 5,280 cubic feet per acre in a fully stocked, 92E-Josephine -Speaker complex, 12 to 35 percent even-aged stand of trees at 40 years and 56,870 board feet north slopes. This map unit is on hillslopes. Elevation is per acre (Scribner rule) at 110 years. 1,200 to 4,000 feet. The mean annual precipitation is 40 The main limitations affecting timber production are to 50 inches, the mean annual temperature is 45 to 52 erosion, compaction, slumping, seedling mortality, and degrees F, and the average frost-free period is 100 to plant competition. Using standard wheeled and tracked 160 days. The native vegetation is mainly conifers and equipment when the soils are moist causes rutting and hardwoods and an understory of grasses, shrubs, and compaction. Puddling can occur when the soils are wet. forbs. Using low-pressure ground equipment causes less damage This unit is about 55 percent Josephine soil and 25 to the soils and helps to maintain productivity. Compaction percent Speaker soil. The components of this unit occur as can be minimized by using suitable methods of harvesting, areas so intricately intermingled that mapping them laying out skid trails in advance, and harvesting timber separately was not practical at the scale used. when the soils are least susceptible to compaction. Ripping Included in this unit are small areas of Dubakella, skid trails and landings when the soils are dry can improve Goolaway, and Wolfpeak soils; Abegg soils on alluvial fans the growth of plants. and near drainageways; Pollard soils on concave slopes; Properly designed road drainage systems that include Beekman soils on the more sloping parts of the landscape carefully located culverts help to control erosion. Seeding, and on convex slopes; poorly drained soils near mulching, and benching areas that have been cut and filled drainageways and on concave slopes; and soils that are also help to control erosion. Steep yarding paths, skid trails, similar to the Josephine and Speaker soils but have more and firebreaks are subject to rilling and gullying unless they than 35 percent rock fragments. Also included are small are protected by a plant cover or adequate water bars, or areas of Josephine and Speaker soils that have slopes of both. Skid trails and unsurfaced roads may be impassable less than 12 or more than 35 percent. Included areas make during rainy periods. Logging roads require suitable up about 20 percent of the total acreage. surfacing for year-round use. The Josephine soil is deep and well drained. It formed in The Pollard soil is subject to slumping. Road failure and colluvium and residuum derived dominantly from landslides are likely to occur after road construction and metamorphic rock. Typically, the surface is covered with a clearcutting. Clearcutting increases the hazard of slumping layer of needles, leaves, and twigs about 1 inch thick. The on this unit. Slumping can be minimized by constructing surface layer is dark reddish brown gravelly loam about 15 logging roads in the less sloping areas, on better suited inches thick. The subsoil is dark reddish brown and reddish soils if practical, and by installing properly designed road brown gravelly clay loam about 40 inches thick. Weathered drainage systems. Skid trails and unsurfaced roads may be bedrock is at a depth of about 55 inches. The depth to impassable during rainy periods. Logging roads require bedrock ranges from 40 to 60 inches. In some areas the suitable surfacing for year-round use. surface layer is clay loam. A high temperature in the surface layer and an Permeability is moderately slow in the Josephine soil. insufficient moisture supply in summer increase the Available water capacity is about 7 inches. The effective seedling mortality rate. To compensate for the expected rooting depth is 40 to 60 inches. Runoff is medium, and the high mortality rate, the larger seedlings or a greater number hazard of water erosion is moderate. of seedlings should be planted. When the The Speaker soil is moderately deep and well drained. It formed in colluvium derived dominantly from metamorphic rock. Typically, the surface is covered with a and gullying unless they are protected by a plant cover or layer of needles, leaves, and twigs about 1 inch thick. The adequate water bars, or both. Skid trails and unsurfaced surface layer is dark brown loam about 13 inches thick. The roads may be impassable during rainy periods. Logging upper 10 inches of the subsoil also is dark brown loam. The roads require suitable surfacing for year-round use. lower 12 inches is brown gravelly clay loam. Weathered Undesirable plants limit natural or artificial reforestation bedrock is at a depth of about 35 inches. The depth to unless intensive site preparation and maintenance bedrock ranges from 20 to 40 inches. In some areas the measures are applied. Reforestation can be accomplished surface layer is gravelly loam. by planting Douglas fir seedlings. Mulching around Permeability is moderately slow in the Speaker soil. seedlings helps to maintain the moisture supply in Available water capacity is about 4 inches. The effective summer and minimizes competition from undesirable rooting depth is 20 to 40 inches. Runoff is medium, and the understory plants. hazard of water erosion is moderate. The vegetative site is Douglas Fir-Chinkapin Forest. This unit is used for timber production and wildlife habitat. It is suited to the production of Douglas fir. Other 92F-Josephine-Speaker complex, 35 to 55 percent species that grow on this unit include ponderosa pine, north slopes. This map unit is on hillslopes. Elevation is incense cedar, and golden chinkapin. The understory 1,200 to 4,000 feet. The mean annual precipitation is 40 vegetation includes creambush oceanspray, cascade to 50 inches, the mean annual temperature is 45 to 52 Oregongrape, and deerfoot vanillaleaf. degrees F, and the average frost-free period is 100 to On the basis of a 100-year site curve, the mean site 160 days. The native vegetation is mainly conifers and index for Douglas fir is 130 on the Josephine soil. The yield hardwoods and an understory of grasses, shrubs, and at culmination of the mean annual increment is 7,740 cubic forbs. feet per acre in a fully stocked, even-aged stand of trees at This unit is about 55 percent Josephine soil and 30 60 years and 58,520 board feet per acre (Scribner rule) at percent Speaker soil. The components of this unit occur as 110 years. On the basis of a 50-year curve, the mean site areas so intricately intermingled that mapping them index is 95. separately was not practical at the scale used. On the basis of a 100-year site curve, the mean site Included in this unit are small areas of Dubakella, index for Douglas fir is 120 on the Speaker soil. The yield Goolaway, Pearsoll, and Siskiyou soils; Pollard soils on the at culmination of the mean annual increment is 6,900 cubic less sloping parts of the landscape and on concave slopes; feet per acre in a fully stocked, even-aged stand of trees at Beekman and McMullin soils on the more sloping parts of 60 years and 52,440 board feet per acre (Scribner rule) at the landscape; poorly drained soils near drainageways and 120 years. On the basis of a 50-year curve, the mean site on concave slopes; and soils that are similar to the index is 90. Josephine and Speaker soils but have more than 35 percent The main limitations affecting timber production are rock fragments. Also included are small areas of Josephine erosion, compaction, and plant competition. Wheeled and and Speaker soils that have slopes of less than 35 or more tracked logging equipment can be used in the less sloping than 55 percent. Included areas make up about 15 percent areas, but cable yarding generally is safer in the more of the total acreage. sloping areas and results in less surface disturbance. Using The Josephine soil is deep and well drained. It formed in standard wheeled and tracked equipment when the soils colluvium and residuum derived dominantly from are moist causes rutting and compaction. Puddling can metamorphic rock. Typically, the surface is covered with a occur when the soils are wet. Using low-pressure ground layer of needles, leaves, and twigs about 1 inch thick. The equipment causes less damage to the soils and helps to surface layer is dark reddish brown gravelly loam about 15 maintain productivity. Compaction can be minimized by inches thick. The subsoil is dark reddish brown and reddish using suitable methods of harvesting, laying out skid trails in brown gravelly clay loam about 40 inches thick. Weathered advance, and harvesting timber when the soils are least bedrock is at a depth of about 55 inches. The depth to susceptible to compaction. Ripping skid trails and landings bedrock ranges from 40 to 60 inches. In some areas the when the soils are dry can improve the growth of plants. surface layer is clay loam. Properly designed road drainage systems that include Permeability is moderately slow in the Josephine soil. carefully located culverts help to control erosion. Seeding, Available water capacity is about 7 inches. The effective mulching, and benching areas that have been cut and filled rooting depth is 40 to 60 inches. Runoff is rapid, and the also help to control erosion. Steep yarding paths, skid trails, hazard of water erosion is high. and firebreaks are subject to rilling The Speaker soil is moderately deep and well drained. It formed in colluvium derived dominantly from and gullying unless they are protected by a plant cover or metamorphic rock. Typically, the surface is covered with a adequate water bars, or both. Cutbanks occasionally slump layer of needles, leaves, and twigs about 1 inch thick. The when the soils are saturated. surface layer is dark brown loam about 13 inches thick. The Constructing logging roads on the steeper slopes can upper 10 inches of the subsoil also is dark brown loam. The result in a high risk of erosion. Material that is discarded lower 12 inches is brown gravelly clay loam. Weathered when the roads are built can damage vegetation and is a bedrock is at a depth of about 35 inches. The depth to potential source of sedimentation. If the material becomes bedrock ranges from 20 to 40 inches. In some areas the saturated, avalanches of debris can occur. End hauling of surface layer is gravelly loam. the waste material minimizes damage to the vegetation Permeability is moderately slow in the Speaker soil. downslope and reduces the risk of sedimentation. Skid trails Available water capacity is about 4 inches. The effective and unsurfaced roads may be impassable during rainy rooting depth is 20 to 40 inches. Runoff is rapid, and the periods. Logging roads require suitable surfacing for hazard of water erosion is high. year-round use. This unit is used for timber production and wildlife Undesirable plants limit natural or artificial reforestation habitat. It is suited to the production of Douglas fir. Other unless intensive site preparation and maintenance species that grow on this unit include ponderosa pine, measures are applied. Reforestation can be accomplished incense cedar, and golden chinkapin. The understory by planting Douglas fir seedlings. Mulching around vegetation includes creambush oceanspray, cascade seedlings helps to maintain the moisture supply in Oregongrape, and deerfoot vanillaleaf. summer and minimizes competition from undesirable On the basis of a 100-year site curve, the mean site understory plants. index for Douglas fir is 130 on the Josephine soil. The yield The vegetative site is Douglas Fir-Chinkapin Forest. at culmination of the mean annual increment is 7,740 cubic feet per acre in a fully stocked, even-aged stand of trees at 93E-Josephine -Speaker complex, 12 to 35 percent 60 years and 58,520 board feet per acre (Scribner rule) at south slopes. This map unit is on hillslopes. Elevation is 110 years. On the basis of a 50-year curve, the mean site 1,200 to 4,000 feet. The mean annual precipitation is 40 index is 95. to 50 inches, the mean annual temperature is 45 to 52 On the basis of a 100-year site curve, the mean site degrees F, and the average frost-free period is 100 to index for Douglas fir is 120 on the Speaker soil. The yield 160 days. The native vegetation is mainly conifers and at culmination of the mean annual increment is 6,900 cubic hardwoods and an understory of grasses, shrubs, and feet per acre in a fully stocked, even-aged stand of trees at forbs. 60 years and 52,440 board feet per acre (Scribner rule) at This unit is about 45 percent Josephine soil and 35 120 years. On the basis of a 50-year curve, the mean site percent Speaker soil. The components of this unit occur as index is 90. areas so intricately intermingled that mapping them The main limitations affecting timber production are the separately was not practical at the scale used. slope, erosion, compaction, and plant competition. Wheeled Included in this unit are small areas of Dubakella, and tracked logging equipment can be used in the less Goolaway, and Wolfpeak soils; Abegg soils on alluvial fans sloping areas, but cable yarding generally is safer and and near drainageways; Pollard soils on concave slopes; results in less surface disturbance. Using standard wheeled Beekman soils on the more sloping parts of the landscape and tracked equipment when the soils are moist causes and on convex slopes; poorly drained soils near rutting and compaction. Puddling can occur when the soils drainageways and on concave slopes; and soils that are are wet. Using low-pressure ground equipment causes less similar to the Josephine and Speaker soils but have more damage to the soils and helps to maintain productivity. than 35 percent rock fragments. Also included are small Compaction can be minimized by using suitable methods of areas of Josephine and Speaker soils that have slopes of harvesting, laying out skid trails in advance, and harvesting less than 12 or more than 35 percent. Included areas make timber when the soils are least susceptible to compaction. up about 20 percent of the total acreage. Ripping skid trails and landings when the soils are dry can The Josephine soil is deep and well drained. It formed in improve the growth of plants. colluvium and residuum derived dominantly from Properly designed road drainage systems that include metamorphic rock. Typically, the surface is covered with a carefully located culverts help to control erosion. Seeding, layer of needles, leaves, and twigs about 1 inch thick. The mulching, and benching areas that have been cut and filled surface layer is dark reddish brown gravelly loam about 15 also help to control erosion. Steep yarding paths, skid trails, inches thick. The subsoil is dark reddish brown and reddish and firebreaks are subject to rilling brown gravelly clay loam about 40 inches thick. Weathered bedrock is at a depth of about 55 inches. The depth to bedrock ranges from 40 to The main limitations affecting timber production are 60 inches. In some areas the surface layer is clay loam. erosion, compaction, seedling mortality, and plant Permeability is moderately slow in the Josephine soil. competition. Wheeled and tracked logging equipment can Available water capacity is about 7 inches. The effective be used in the less sloping areas, but cable yarding rooting depth is 40 to 60 inches. Runoff is medium, and the generally is safer in the more sloping areas and results in hazard of water erosion is moderate. less surface disturbance. Using standard wheeled and The Speaker soil is moderately deep and well drained. It tracked equipment when the soils are moist causes rutting formed in colluvium derived dominantly from metamorphic and compaction. Puddling can occur when the soils are wet. rock. Typically, the surface is covered with a layer of Using low-pressure ground equipment causes less damage needles, leaves, and twigs about 1 inch thick. The surface to the soils and helps to maintain productivity. Compaction layer is dark brown loam about 13 inches thick. The upper can be minimized by using suitable methods of harvesting, 10 inches of the subsoil also is dark brown loam. The lower laying out skid traits in advance, and harvesting timber when 12 inches is brown gravelly clay loam. Weathered bedrock the soils are least susceptible to compaction. Ripping skid is at a depth of about 35 inches. The depth to bedrock trails and landings when the soils are dry can improve the ranges from 20 to 40 inches. In some areas the surface growth of plants. layer is gravelly loam. Properly designed road drainage systems that include Permeability is moderately slow in the Speaker soil. carefully located culverts help to control erosion. Seeding, Available water capacity is about 4 inches. The effective mulching, and benching areas that have been cut and filled rooting depth is 20 to 40 inches. Runoff is medium, and the also help to control erosion. Steep yarding paths, skid trails, hazard of water erosion is moderate. and firebreaks are subject to rilling and gullying unless they This unit is used for timber production and wildlife are protected by a plant cover or adequate water bars, or habitat. It is suited to the production of Douglas fir and both. Skid trails and unsurfaced roads may be impassable ponderosa pine. Other species that grow on this unit during rainy periods. Logging roads require suitable include sugar pine and California black oak. The surfacing for year-round use. understory vegetation includes canyon live oak, A high temperature in the surface layer and an deerbrush, and western fescue. insufficient moisture supply in summer increase the seedling On the basis of a 100-year site curve, the mean site mortality rate. To compensate for the expected high index for Douglas fir is 120 on the Josephine soil. The yield mortality rate, the larger seedlings or a greater number of at culmination of the mean annual increment is 6,900 cubic seedlings should be planted. When the timber is harvested, feet per acre in a fully stocked, even-aged stand of trees at leaving some of the larger trees unharvested provides 60 years and 52,440 board feet per acre (Scribner rule) at shade for seedlings. The seedling mortality rate also can be 120 years. On the basis of a 50-year curve, the mean site reduced by providing artificial shade for seedlings. index is 90. Reforestation can be accomplished by planting Douglas fir On the basis of a 100-year site curve, the mean site and ponderosa pine seedlings. index for ponderosa pine is 115 on the Josephine soil. The Undesirable plants limit natural or artificial yield at culmination of the mean annual increment is 5,280 reforestation unless intensive site preparation and cubic feet per acre in a fully stocked, even-aged stand of maintenance measures are applied. Mulching around trees at 40 years and 56,870 board feet per acre (Scribner seedlings helps to maintain the moisture supply in rule) at 110 years. summer and minimizes competition from undesirable On the basis of a 100-year site curve, the mean site understory plants. index for Douglas fir is 115 on the Speaker soil. The yield The vegetative site is Douglas Fir-Black Oak Forest. at culmination of the mean annual increment is 6,360 cubic feet per acre in a fully stocked, even-aged stand of trees at 94G-Kanid-Atring very gravelly loams, 50 to 80 60 years and 50,700 board feet per acre (Scribner rule) at percent north slopes. This map unit is on hillslopes. 130 years. On the basis of a 50-year curve, the mean site Elevation is 2,400 to 4,100 feet. The mean annual index is 85. precipitation is 45 to 60 inches, the mean annual On the basis of a 100-year site curve, the mean site temperature is 47 to 50 degrees F, and the average index for ponderosa pine is 105 on the Speaker soil. The frost-free period is 100 to 160 days. The native yield at culmination of the mean annual increment is 4,480 vegetation is mainly conifers and an understory of cubic feet per acre in a fully stocked, even-aged stand of grasses, shrubs, and forbs. trees at 40 years and 50,040 board feet per acre (Scribner This unit is about 60 percent Kanid soil and 20 percent rule) at 120 years. Atring soil. The components of this unit occur as areas so intricately intermingled that mapping them The main limitations affecting timber production are the separately was not practical at the scale used. slope, erosion, plant competition, and seedling mortality. Included in this unit are small areas of Dubakella, Also, the bedrock restricts root growth. As a result, Gravecreek, Norling, Pearsoll, and Steinmetz soils; Rock windthrow is a hazard. outcrop; Acker soils on the less sloping parts of the The slope restricts the use of wheeled and tracked landscape; and, on ridges and convex slopes, soils that are logging equipment. High-lead or other cable systems are similar to the Atring soil but have bedrock within a depth of the best methods of logging. If the soils are excessively 20 inches. Also included are small areas of Kanid and disturbed when timber is harvested or logging roads are Atring soils that have slopes of less than 50 or more than built, a larger number of rock fragments is left on the 80 percent. Included areas make up about 20 percent of surface. Ripping landings when the soils are dry can the total acreage. improve the growth of plants. The Kanid soil is deep and well drained. It formed in Properly designed road drainage systems that include colluvium derived dominantly from metamorphic rock. carefully located culverts help to control erosion. Road cuts Typically, the surface is covered with a layer of needles, can expose a large amount of fractured bedrock, which leaves, and twigs about 1 inch thick. The surface layer is limits the response to seeding and mulching. Cut slopes are dark brown and brown very gravelly loam about 18 inches subject to slumping where the bedrock is highly fractured or thick. The subsoil is yellowish brown and light olive brown where rock layers are parallel to the slopes. Steep yarding very gravelly clay loam about 29 inches thick. Weathered paths and firebreaks are subject to rilling and gullying unless bedrock is at a depth of about 47 inches. The depth to they are protected by a plant cover or adequate water bars, bedrock ranges from 40 to 60 inches. In some areas the or both. surface layer is stony. Building logging roads at midslope requires extensive Permeability is moderately rapid in the Kanid soil. cutting and filling and removes land from production. Available water capacity is about 4 inches. The effective Material that is discarded when the roads are built can rooting depth is 40 to 60 inches. Runoff is rapid, and the damage vegetation and is a potential source of hazard of water erosion is high. sedimentation. If the material becomes saturated, The Atring soil is moderately deep and well drained. It avalanches of debris can occur. End hauling of the waste formed in colluvium derived dominantly from metamorphic material minimizes damage to the vegetation downslope rock. Typically, the surface is covered with a layer of and reduces the risk of sedimentation. Unsurfaced roads needles, leaves, and twigs about 1 inch thick. The surface may be impassable during rainy periods. Logging roads layer is very dark brown very gravelly loam about 7 inches require suitable surfacing for year-round use. thick. The subsoil is brown and yellowish brown very Undesirable plants limit natural or artificial reforestation gravelly loam about 33 inches thick. Weathered bedrock is unless intensive site preparation and maintenance at a depth of about 40 inches. The depth to bedrock ranges measures are applied. Reforestation can be accomplished from 20 to 40 inches. In some areas the surface layer is by planting Douglas fir seedlings. Mulching around stony. seedlings helps to maintain the moisture supply in Permeability is moderately rapid in the Atring soil. summer and minimizes competition from undesirable Available water capacity is about 3 inches. The effective understory plants. rooting depth is 20 to 40 inches. Runoff is rapid, and the A high temperature in the surface layer during summer hazard of water erosion is high. and the low available water capacity increase the seedling This unit is used for timber production and wildlife mortality rate. The large number of rock fragments in the habitat. It is suited to the production of Douglas fir. soils also increases the seedling mortality rate. To Other species that grow on this unit include incense compensate for the expected high mortality rate, the larger cedar, golden chinkapin, and western hemlock. The seedlings or a greater number of seedlings should be understory vegetation includes salal, cascade planted. When the timber is harvested, leaving some of the Oregongrape, and deerfoot vanillaleaf. larger trees unharvested provides shade for seedlings. On the basis of a 100-year site curve, the mean site Increased erosion, loss of plant nutrients, and water index for Douglas fir is 130 on both the Kanid and Atring repellency are likely to result from fires of moderate soils. The yield at culmination of the mean annual intensity. increment is 7,800 cubic feet per acre in a fully stocked, The vegetative site is Mixed Fir-Salal (rhododendron) even-aged stand of trees at 60 years and 58,520 board Forest. feet per acre (Scribner rule) at 110 years. On the basis of a 50-year curve, the mean site index is 95. 95G-Kanid-Atring very gravelly loams, 50 to 80 Oregongrape, and deerfoot vanillaleaf. percent south slopes. This map unit is on hillslopes. On the basis of a 100-year site curve, the mean site Elevation is 2,400 to 4,100 feet. The mean annual index for Douglas fir is 120 on both the Kanid and Atring precipitation is 45 to 60 inches, the mean annual soils. The yield at culmination of the. mean annual temperature is 47 to 50 degrees F, and the average increment is 6,900 cubic feet per acre in a fully stocked, frost-free period is 100 to 160 days. The native even-aged stand of trees at 60 years and 52,440 board feet vegetation is mainly conifers and an understory of per acre (Scribner rule) at 120 years. On the basis of a grasses, shrubs, and forbs. 50-year curve, the mean site index is 90. This unit is about 60 percent Kanid soil and 20 percent The main limitations affecting timber production are the Atring soil. The components of this unit occur as areas so slope, erosion, seedling mortality, and plant competition. intricately intermingled that mapping them separately was Also, the bedrock restricts root growth. As a result, not practical at the scale used. windthrow is a hazard. Included in this unit are small areas of Dubakella, The slope restricts the use of wheeled and tracked Gravecreek, Norling, Pearsoll, and Steinmetz soils; Rock logging equipment. High-lead or other cable systems are outcrop; Acker soils on the less sloping parts of the the best methods of logging. If the soils are excessively landscape; and, on ridges and convex slopes, soils that are disturbed when timber is harvested or logging roads are similar to the Atring soil but have bedrock within a depth of built, a larger number of rock fragments is left on the 20 inches. Also included are small areas of Kanid and surface. Ripping landings when the soils are dry can Atring soils that have slopes of less than 50 or more than improve the growth of plants. 80 percent. Included areas make up about 20 percent of Properly designed road drainage systems that include the total acreage. carefully located culverts help to control erosion. Road cuts The Kanid soil is deep and well drained. It formed in can expose a large amount of fractured bedrock, which colluvium derived dominantly from metamorphic rock. limits the response to seeding and mulching. Cut slopes are Typically, the surface is covered with a layer of needles, subject to slumping where the bedrock is highly fractured or leaves, and twigs about 1 inch thick. The surface layer is where rock layers are parallel to the slopes. Steep yarding dark brown and brown very gravelly loam about 18 inches paths and firebreaks are subject to rilling and gullying thick. The subsoil is yellowish brown and light olive brown unless they are protected by a plant cover or adequate very gravelly clay loam about 29 inches thick. Weathered water bars, or both. bedrock is at a depth of about 47 inches. The depth to Building logging roads at midslope requires extensive bedrock ranges from 40 to 60 inches. In some areas the cutting and filling and removes land from production. surface layer is stony. Material that is discarded when the roads are built can Permeability is moderately rapid in the Kanid soil. damage vegetation and is a potential source of Available water capacity is about 4 inches. The effective sedimentation. If the material becomes saturated, rooting depth is 40 to 60 inches. Runoff is rapid, and the avalanches of debris can occur. End hauling of the waste hazard of water erosion is high. material minimizes damage to the vegetation downslope The Atring soil is moderately deep and well drained. It and reduces the risk of sedimentation. Unsurfaced roads formed in colluvium derived dominantly from metamorphic may be impassable during rainy periods. Logging roads rock. Typically, the surface is covered with a layer of require suitable surfacing for year-round use. needles, leaves, and twigs about 1 inch thick. The surface A high temperature in the surface layer during summer layer is very dark brown very gravelly loam about 7 inches and the low available water capacity increase the seedling thick. The subsoil is brown and yellowish brown very mortality rate. To compensate for the expected high gravelly loam about 33 inches thick. Weathered bedrock is mortality rate, the larger seedlings or a greater number of at a depth of about 40 inches. The depth to bedrock ranges seedlings should be planted. When the timber is harvested, from 20 to 40 inches. In some areas the surface layer is leaving some of the larger trees unharvested provides stony. shade for seedlings. The seedling mortality rate also can be Permeability is moderately rapid in the Atring soil. reduced by providing artificial shade for seedlings. Available water capacity is about 3 inches. The effective Reforestation can be accomplished by planting Douglas fir rooting depth is 20 to 40 inches. Runoff is rapid, and the and ponderosa pine seedlings. hazard of water erosion is high. Undesirable plants limit natural or artificial This unit is used for timber production and wildlife reforestation unless intensive site preparation and habitat. It is suited to the production of Douglas fir. Other maintenance measures are applied. Mulching around species that grow on this unit include incense cedar, golden chinkapin, and Pacific madrone. The understory vegetation includes Whipplevine, cascade seedlings helps to maintain the moisture supply in from erosion. Grazing when the soil is wet results in summer and minimizes competition from undesirable compaction of the surface layer, poor tilth, and excessive understory plants. runoff. Periodic mowing and clipping help to maintain Increased erosion, loss of plant nutrients, and water uniform plant growth, discourage selective grazing, and repellency are likely to result from fires of moderate reduce the extent of clumpy growth. intensity. Tufted hairgrass is the native plant preferred for livestock The vegetative site is Douglas Fir-Madrone- grazing; however, this unit can be renovated and forage Chinkapin Forest. production increased by seeding other suitable grasses. The plants selected for seeding should be those that are tolerant 96B-Kanutchan clay, 1 to 8 percent slopes. This of wetness. Border and contour flood irrigation systems are deep, somewhat poorly drained soil is in basins. It formed suitable. Because of the very slow permeability, water in alluvium and colluvium derived dominantly from andesite, applications should be regulated so that the water does not tuff, and breccia. Elevation is 3,600 to 5,500 feet. The stand on the surface and damage the crop. Land leveling mean annual precipitation is 25 to 50 inches, the mean helps to ensure a uniform application of water. Fertilizer is annual temperature is 40 to 45 degrees F, and the average needed to ensure the optimum growth of grasses and frost-free period is less than 100 days. The native legumes. Grasses respond to nitrogen, and legumes vegetation is mainly grasses, sedges, and forbs. respond to sulfur and phosphorus. Typically, the surface layer is black clay about 20 The vegetative site is Wet Meadow. inches thick. The subsoil is black and very dark gray clay about 26 inches thick. Bedrock is at a depth of about 46 97A-Kerby loam, 0 to 3 percent slopes. This very inches. The depth to bedrock ranges from 40 to 60 inches. deep, well drained soil is on stream terraces. It formed in In some areas the surface layer is cobbly or stony. alluvium derived from mixed sources. Elevation is 1,000 to Included in this unit are small areas of Bybee, Farva, 2,000 feet. The mean annual precipitation is 18 to 35 inches, Pinehurst, Sibannac, and Tatouche soils. Also included are the mean annual temperature is 50 to 54 degrees F, and the small areas of soils that are similar to the Kanutchan soil average frost-free period is 140 to 180 days. The vegetation but have bedrock at a depth of less than 40 or more than 60 in areas that have not been cultivated is mainly grasses and inches and small areas of Kanutchan soils that have slopes forbs. of more than 8 percent. Included areas make up about 15 Typically, the surface layer is very dark grayish brown percent of the total acreage. loam about 7 inches thick. The subsoil is dark brown loam Permeability is very slow in the Kanutchan soil. Available about 47 inches thick. The substratum to a depth of 60 water capacity is about 7 inches. The effective rooting depth inches is dark brown very gravelly sandy loam. is limited by the water table, which is within a depth of 1.5 Included in this unit are small areas of Gregory and Kubli feet from December through May. Runoff is slow, and the soils on concave slopes, Central Point and Medford soils, hazard of water erosion is slight. and soils that are similar to the Kerby soil but have very This unit is used for livestock grazing and wildlife habitat. gravelly layers within a depth of 40 inches. Also included are It is well suited to permanent pasture. The main limitations small areas of Kerby soils that have slopes of more than 3 affecting livestock grazing are the seasonal wetness, percent. Included areas make up about 20 percent of the compaction, the high content of clay, and a slow rate of total acreage. water intake. The wetness limits the choice of suitable Permeability is moderately slow in the Kerby soil. forage plants and the period of cutting or grazing and Available water capacity is about 10 inches. The effective increases the risk of winterkill. The high content of clay rooting depth is 60 inches or more. Runoff is slow, and severely limits tillage and root growth. Deep cracks form as the hazard of water erosion is slight. the soil dries in summer. This unit is used mainly for irrigated crops, such as If the pasture is overgrazed, the proportion of preferred grass seed, onions, alfalfa, and tree fruit. Other crops forage plants decreases and the proportion of less include strawberries, small grain, and sugar beet seed. preferred forage plants increases. The grazing system Some areas are used for homesite development or should maintain the desired balance of species in the plant pasture. community. Proper stocking rates, pasture rotation, and This unit is well suited to irrigated crops. It has few restricted grazing during wet periods help to keep pastures limitations. In summer, irrigation is needed for the in good condition and protect the soil maximum production of most crops. Furrow, border, corrugation, trickle, and sprinkler irrigation systems are suitable. The system used generally is governed by the crop that is grown. For the efficient application and removal areas that have not been cultivated is mainly hardwoods of surface irrigation water, land leveling is needed. To and an understory of grasses, shrubs, and forbs. prevent overirrigation and the leaching of plant nutrients, Typically, the surface layer is dark brown and dark applications of irrigation water should be adjusted to the yellowish brown loam about 15 inches thick. The subsoil is available water capacity, the rate of water intake, and the brown and dark yellowish brown clay loam about 40 inches needs of the crop. The use of pipe, ditch lining, or drop thick. The substratum to a depth of 60 inches is dark structures in irrigation ditches reduces water loss and the yellowish brown loam. The depth to bedrock is 60 inches or hazard of erosion. more. Returning all crop residue to the soil and using a Included in this unit are small areas of Central Point, cropping system that includes grasses, legumes, or Kerby, and Medford soils; Gregory soils on concave slopes; grass-legume mixtures help to maintain fertility and tilth. and Brader, Debenger, and Langellain soils on convex Leaving crop residue on or near the surface helps to slopes. Also included are small areas of Kerby soils that conserve moisture and control erosion. have slopes of more than 3 percent. Included areas make A tillage pan forms easily if the soil is tilled when wet. up about 15 percent of the total acreage. Chiseling or subsoiling breaks up the pan. Surface crusting Permeability is moderately slow in the Kerby soil. and compaction can be minimized by returning crop residue Available water capacity is about 10 inches. The effective to the soil. rooting depth is limited by the water table, which is at a Solid-set sprinkler irrigation is the best method of depth of 1.5 to 2.5 feet from December through May. controlling frost and providing adequate moisture for tree Runoff is slow, and the hazard of water erosion is slight. fruit. Compaction can be minimized by limiting the use of This unit is used for irrigated small grain and hay and equipment when the soil is wet. A permanent cover crop pasture. helps to control runoff and erosion. This unit is suited to irrigated crops. It is limited mainly by Proper stocking rates, pasture rotation, and restricted wetness in winter and spring. Crops that require good grazing during wet periods help to keep pastures in good drainage can be grown if a properly designed tile drainage condition and protect the soil from erosion. Grazing when system is installed. Tile drainage can lower the water table if the soil is wet results in compaction of the surface layer, a suitable outlet is available. Land smoothing and open poor tilth, and excessive runoff. Periodic mowing and ditches can reduce surface wetness. clipping help to maintain uniform plant growth, discourage In summer, irrigation is needed for the maximum selective grazing, and reduce the extent of clumpy growth. production of most crops. Furrow, border, corrugation, Fertilizer is needed to ensure the optimum growth of trickle, and sprinkler irrigation systems are suitable. The grasses and legumes. Grasses respond to nitrogen, and system used generally is governed by the crop that is legumes respond to sulfur and phosphorus. grown. For the efficient application and removal of surface This unit is well suited to homesite development. It has irrigation water, land leveling is needed. To prevent few limitations. Cutbanks are not stable and are subject to overirrigation and excessive erosion, applications of slumping. To keep cutbanks from caving in, excavations irrigation water should be adjusted to the available water may require special retainer walls. Revegetating as soon as capacity, the rate of water intake, and the needs of the crop. possible helps to control erosion in disturbed areas around The use of pipe, ditch lining, or drop structures in irrigation construction sites. Topsoil can be stockpiled and used to ditches reduces water loss and the hazard of erosion. reclaim areas disturbed during construction. Because of a Returning all crop residue to the soil and using a low amount of rainfall in summer, irrigation is needed in cropping system that includes grasses, legumes, or areas that support lawn grasses, shrubs, vines, shade grass-legume mixtures help to maintain fertility and tilth. trees, or ornamental trees. Leaving crop residue on or near the surface helps to The vegetative site is Deep Loamy Terrace, 18- to conserve moisture and control erosion. 28-inch precipitation zone. A tillage pan forms easily if the soil is tilled when wet. Chiseling or subsoiling breaks up the pan. Surface crusting 98A-Kerby loam, wet, 0 to 3 percent slopes. This very and compaction can be minimized by returning crop residue deep, moderately well drained soil is on stream terraces. It to the soil. formed in alluvium derived from mixed sources. Elevation is The main limitations in the areas used for hay and 1,000 to 1,500 feet. The mean annual precipitation is 18 to pasture are wetness in winter and spring and 35 inches, the mean annual temperature is 50 to 54 compaction. The wetness limits the choice of suitable degrees F, and the average frost-free period is 140 to 180 days. The vegetation in forage plants and the period of cutting or grazing and less preferred forage plants increases. The grazing system increases the risk of winterkill. Proper stocking rates, should maintain the desired balance of species in the plant pasture rotation, and restricted grazing during wet periods community. Proper stocking rates, pasture rotation, and help to keep pastures in good condition and protect the soil restricted grazing during wet periods help to keep pastures from erosion. Grazing when the soil is wet results in in good condition and protect the soil from erosion. Grazing compaction of the surface layer, poor tilth, and excessive when the soil is wet results in compaction of the surface runoff. Periodic mowing and clipping help to maintain layer, poor tilth, and excessive runoff. Periodic mowing and uniform plant growth, discourage selective grazing, and clipping help to maintain uniform plant growth, discourage reduce the extent of clumpy growth. Fertilizer is needed to selective grazing, and reduce the extent of clumpy growth. ensure the optimum growth of grasses and legumes. Fertilizer is needed to ensure the optimum growth of Grasses respond to nitrogen, and legumes respond to sulfur grasses and legumes. Grasses respond to nitrogen, and and phosphorus. legumes respond to sulfur and phosphorus. The vegetative site is Loamy Hills, 20- to 35-inch Tufted hairgrass is the native plant preferred for precipitation zone. livestock grazing; however, this unit can be renovated and forage production increased by seeding other 99A-Klamath silt loam, 0 to 1 percent slopes. This suitable grasses. The plants selected for seeding should very deep, poorly drained soil is on flood plains. It formed in be those that are tolerant of wetness. alluvium derived dominantly from volcanic ash, andesite, The vegetative site is Wet Meadow. and basalt. Elevation is 3,900 to 5,400 feet. The mean annual precipitation is 25 to 35 inches, the mean annual 100A-Kubli loam, 0 to 3 percent slopes. This very temperature is 42 to 45 degrees F, and the average deep, somewhat poorly drained soil is on stream terraces. frost-free period is less than 100 days. The native It formed in alluvium derived dominantly from granitic rock vegetation is mainly grasses, sedges, and forbs. and underlain by clayey sediment. Elevation is 1,000 to Typically, the surface layer is black silt loam about 3 2,300 feet. The mean annual precipitation is 18 to 30 inches thick. The next layer is black clay about 8 inches inches, the mean annual temperature is 50 to 54 degrees thick. The subsoil is very dark gray and dark gray silty clay F, and the average frost-free period is 150 to 180 days. about 26 inches thick. The substratum to a depth of 62 The vegetation in areas that have not been cultivated is inches is gray silty clay loam and clay loam. The depth to mainly grasses and forbs. bedrock is 60 inches or more. In some areas the surface Typically, the surface layer is very dark brown loam layer is gravelly or cobbly. about 9 inches thick. The next layer is very dark grayish Included in this unit are small areas of Pokegema and brown loam about 6 inches thick. The subsoil is dark Woodcock soils; very stony, shallow soils; and very poorly grayish brown loam about 16 inches thick. The upper 16 drained, organic soils. Also included are small areas of soils inches of the substratum is brown clay. The lower part to a that are similar to the Klamath soil but are well drained or depth of 60 inches is brown clay loam. are not flooded and small areas of Klamath soils that have Included in this unit are small areas of Medford soils, slopes of more than 1 percent. Included areas make up Barron and Central Point soils on the higher terraces and about 10 percent of the total acreage. alluvial fans, and Gregory soils and poorly drained or very Permeability is slow in the Klamath soil. Available water poorly drained, loamy soils near drainageways and on capacity is about 13 inches. The effective rooting depth is concave slopes. Also included are small areas of Kubli soils limited by the water table, which is within a depth of 3 feet that have slopes of more than 3 percent. Included areas from March through June. Runoff is slow, and the hazard of make up about 10 percent of the total acreage. water erosion is slight. This soil is frequently flooded for Permeability is moderate to a depth of 31 inches in the long periods from March through May. Kubli soil and very slow below that depth. Available water This unit is used for livestock grazing and wildlife habitat. capacity is about 10 inches. The effective rooting depth is It is suited to pasture. The main limitations affecting limited by the dense, clayey substratum, which is at a depth livestock grazing are the flooding, the seasonal wetness, of 25 to 35 inches. Runoff is slow, and the hazard of water compaction, and a short growing season. The wetness limits erosion is slight. The water table, which is perched above the choice of suitable forage plants and the period of the layer of clay, is at a depth of 0.5 foot to 3.0 feet from grazing and increases the risk of winterkill. November through April. If the pasture is overgrazed, the proportion of preferred This unit is used mainly for homesite development, forage plants decreases and the proportion of pasture, or irrigated crops, such as alfalfa hay, small grain, and grass-legume hay. It also is used for tree water and thus improve the efficiency of the absorption fruit, sugar beet seed, and corn for silage. fields. Alternative waste disposal systems may function This unit is suited to irrigated crops. It is limited mainly by properly on this unit. Suitable included soils are throughout wetness in winter and spring and the very slow permeability. the unit. Onsite investigation is needed to locate such Crops that require good drainage can be grown if a properly soils. designed tile drainage system is installed. Tile drainage can Because the seasonal high water table is perched lower the water table if collection laterals are closely spaced above the layer of clay, a drainage system is needed if and a suitable outlet is available. Land smoothing and open buildings with basements and crawl spaces are ditches can reduce the surface wetness. constructed on this unit. The wetness can be reduced by In summer, irrigation is needed for the maximum installing drainage tile around footings. Properly designing production of most crops. Furrow, border, corrugation, foundations and footings, diverting runoff away from the trickle, and sprinkler irrigation systems are suitable. The buildings, and backfilling with material that has a low system used generally is governed by the crop that is shrink-swell potential help to prevent the structural damage grown. For the efficient application and removal of surface caused by shrinking and swelling. Properly designing irrigation water, land leveling is needed. To prevent buildings and roads helps to offset the limited ability of the overirrigation and the development of a perched water table, soil to support a load. applications of irrigation water should be adjusted to the Revegetating as soon as possible helps to control available water capacity, the rate of water intake, and the erosion in disturbed areas around construction sites. needs of the crop. The use of pipe, ditch lining, or drop Topsoil can be stockpiled and used to reclaim areas structures in irrigation ditches reduces water loss and the disturbed during construction. In many areas it may be hazard of erosion. necessary to haul in topsoil for lawns and gardens. Returning all crop residue to the soil and using a Because of a low amount of rainfall in summer, irrigation is cropping system that includes grasses, legumes, or needed in areas that support lawn grasses, shrubs, vines, grass-legume mixtures help to maintain fertility and tilth. shade trees, or ornamental trees. Leaving crop residue on or near the surface helps to The vegetative site is Deep Loamy Terrace, 18- to conserve moisture and control erosion. 28-inch precipitation zone. A tillage pan forms easily if the soil is tilled when wet. Chiseling or subsoiling breaks up the pan. Surface crusting 100B-Kubli loam, 3 to 7 percent slopes. This very and compaction can be minimized by returning crop residue deep, somewhat poorly drained soil is on terraces. It formed to the soil. in alluvium derived dominantly from granitic rock and Solid-set sprinkler irrigation is the best method of underlain by clayey sediment. Elevation is 1,000 to 2,300 controlling frost and providing adequate moisture for tree feet. The mean annual precipitation is 18 to 30 inches, the fruit. Compaction can be minimized by limiting the use of mean annual temperature is 50 to 54 degrees F, and the equipment when the soil is wet. A permanent cover crop average frost-free period is 150 to 180 days. The vegetation helps to control runoff and erosion. in areas that have not been cultivated is mainly grasses and Proper stocking rates, pasture rotation, and restricted forbs. grazing during wet periods help to keep pastures in good Typically, the surface layer is very dark brown loam condition and protect the soil from erosion. Grazing when about 9 inches thick. The next layer is very dark grayish the soil is wet results in compaction of the surface layer, brown loam about 6 inches thick. The subsoil is dark grayish poor tilth, and excessive runoff. Periodic mowing and brown loam about 16 inches thick. The upper 16 inches of clipping help to maintain uniform plant growth, discourage the substratum is brown clay. The lower part to a depth of selective grazing, and reduce the extent of clumpy growth. 60 inches is brown clay loam. Fertilizer is needed to ensure the optimum growth of Included in this unit are small areas of Medford soils, grasses and legumes. Grasses respond to nitrogen, and Barron and Central Point soils on the higher terraces and legumes respond to sulfur and phosphorus. alluvial fans, and Gregory soils and poorly drained or very The main limitations affecting homesite development poorly drained, loamy soils near drainageways and on are the wetness, the very slow permeability in the concave slopes. Also included are small areas of Kubli soils substratum, a high shrink-swell potential, and low strength. that have slopes of less than 3 or more than 7 percent. The very slow permeability and the perched water table Included areas make up about 10 percent of the total increase the possibility that septic tank absorption fields acreage. will fail. Interceptor ditches can divert subsurface Permeability is moderate to a depth of 31 inches in the Kubli soil and very slow below that depth. Available water capacity is about 10 inches. The effective rooting depth is limited by the dense, clayey substratum, which is at a depth of 25 to 35 inches. Runoff is slow, and the shrink-swell potential, and low strength. hazard of water erosion is slight. The water table, which is The very slow permeability and the seasonal high water perched above the layer of clay, is at a depth of 0.5 foot to table increase the possibility that septic tank absorption 3.0 feet from November through April. fields will fail. Interceptor ditches can divert subsurface This unit is used mainly for homesite development or for water and thus improve the efficiency of the absorption hay and pasture. It also is used for tree fruit. fields. Alternative waste disposal systems may function This unit is suited to irrigated crops. It is limited mainly by properly on this unit. Suitable included soils are throughout wetness in winter and spring, the very slow permeability, the unit. Onsite investigation is needed to locate such soils. and the slope. Crops that require good drainage can be Because the seasonal high water table is perched above grown if a properly designed tile drainage system is the layer of clay, a drainage system is needed on sites for installed. Tile drainage can lower the water table if collection buildings with basements and crawl spaces. The wetness laterals are closely spaced and a suitable outlet is available. can be reduced by installing drainage tile around footings. Open ditches and land smoothing on the less sloping parts Properly designing foundations and footings, diverting runoff of the landscape can reduce surface wetness. away from the buildings, and backfilling with material that In summer, irrigation is needed for the maximum has a low shrink-swell potential help to prevent the structural production of most crops. Furrow, border, corrugation, damage caused by shrinking and swelling. Properly trickle, and sprinkler irrigation systems are suitable. The designing buildings and roads helps to offset the limited system used generally is governed by the crop that is ability of the soil to support a load. grown. For the efficient application and removal of surface Revegetating as soon as possible helps to control irrigation water, land leveling is needed. To prevent erosion in disturbed areas around construction sites. overirrigation and the development of a perched water table, Topsoil can be stockpiled and used to reclaim areas applications of irrigation water should be adjusted to the disturbed during construction. In many areas it may be available water capacity, the rate of water intake, and the necessary to haul in topsoil for lawns and gardens. needs of the crop. The use of pipe, ditch lining, or drop Because of a low amount of rainfall in summer, irrigation is structures in irrigation ditches reduces water loss and the needed in areas that support lawn grasses, shrubs, vines, hazard of erosion. shade trees, or ornamental trees. Returning all crop residue to the soil and using a The vegetative site is Deep Loamy Terrace, 18- to cropping system that includes grasses, legumes, or 28-inch precipitation zone. grass-legume mixtures help to maintain fertility and tilth. Leaving crop residue on or near the surface helps to 101E-Langellain loam, 15 to 40 percent north slopes. conserve moisture and control erosion. This moderately deep, moderately well drained soil is on A tillage pan forms easily if the soil is tilled when wet. hillslopes. It formed in colluvium and alluvium derived Chiseling or subsoiling breaks up the pan. Surface crusting dominantly from sedimentary rock. Elevation is 1,300 to and compaction can be minimized by returning crop residue 3,200 feet. The mean annual precipitation is 18 to 40 to the soil. inches, the mean annual temperature is 48 to 54 degrees F, Solid-set sprinkler irrigation is the best method of and the average frost-free period is 130 to 180 days. The controlling frost and providing adequate moisture for tree native vegetation is mainly conifers and hardwoods and an fruit. Compaction can be minimized by limiting the use of understory of grasses, shrubs, and forbs. equipment when the soil is wet. A permanent cover crop Typically, the surface is covered with a layer of grasses, helps to control runoff and erosion. twigs, and leaves about 1/2 inch thick. The surface layer is Proper stocking rates, pasture rotation, and restricted dark reddish brown loam about 6 inches thick. The next grazing during wet periods help to keep pastures in good layer is dark brown loam about 4 inches thick. The upper 11 condition and protect the soil from erosion. Grazing when inches of the subsoil is strong brown loam. The lower 17 the soil is wet results in compaction of the surface layer, inches is brown and yellowish brown clay. Weathered poor tilth, and excessive runoff. Periodic mowing and bedrock is at a depth of about 38 inches. The depth to clipping help to maintain uniform plant growth, discourage bedrock ranges from 20 to 40 inches. selective grazing, and reduce the extent of clumpy growth. Included in this unit are small areas of Debenger soils, Fertilizer is needed to ensure the optimum growth of Carney and Selmac soils on concave slopes, Brader soils grasses and legumes. Grasses respond to nitrogen, and on ridges and convex slopes, Ruch and Manita soils on legumes respond to sulfur and phosphorus. foot slopes, and soils that are similar to The main limitations affecting homesite development are the wetness, the very slow permeability, a high the Langellain soil but have bedrock at a depth of more of the mean annual increment is 3,400 cubic feet per acre than 40 inches. Also included are small areas of Langellain in a fully stocked, even-aged stand of trees at 40 years soils that have slopes of less than 15 or more than 40 and 37,960 board feet per acre (Scribner rule) at 130 percent. Included areas make up about 20 percent of the years. total acreage. The main limitations affecting timber production are Permeability is moderate to a depth of 21 inches in the erosion, compaction, slumping, the seasonal wetness, Langellain soil and very slow below that depth. Available plant competition, and seedling mortality. Also, the water capacity is about 4 inches. The effective rooting depth bedrock restricts root growth. As a result, windthrow is a is limited by the layer of dense clay in the subsoil. This layer hazard. is at a depth of 12 to 28 inches. Runoff is medium or rapid, The perched seasonal high water table limits the use of and the hazard of water erosion is moderate or high. The equipment to dry periods. Wheeled and tracked logging water table, which is perched above the layer of clay, is at a equipment can be used in the less sloping areas, but cable depth of 0.5 foot to 2.0 feet from December through May. yarding generally is safer in the more sloping areas and This unit is used for livestock grazing, timber results in less surface disturbance. Using standard wheeled production, and wildlife habitat. and tracked equipment when the soil is moist causes rutting The main limitations affecting livestock grazing are and compaction. Puddling can occur when the soil is wet. compaction, erosion, and seasonal wetness. The Using low-pressure ground equipment causes less damage vegetation suitable for grazing includes western fescue, to the soil and helps to maintain productivity. Compaction mountain brome, and tall trisetum. If the understory is can be minimized by using suitable methods of harvesting, overgrazed, the proportion of preferred forage plants laying out skid trails in advance, and harvesting timber decreases and the proportion of less preferred forage when the soil is least susceptible to compaction. Ripping plants increases. skid trails and landings when the soil is dry can improve the A planned grazing system that includes timely deferment growth of plants. of grazing, rotation grazing, and proper livestock distribution Properly designed road drainage systems that include helps to prevent overgrazing of the understory and damage carefully located culverts help to control erosion. Areas that to the soil. Because this soil remains wet for long periods in have been cut and filled are easily eroded unless they are spring, grazing should be delayed until the more desirable treated. Seeding, mulching, and benching these areas help forage plants have achieved enough growth to withstand to control erosion. Steep yarding paths, skid trails, and grazing pressure and the soil is firm enough to withstand firebreaks are subject to rilling and gullying unless they are trampling by livestock. protected by a plant cover or adequate water bars, or both. Thinning, logging, and fire reduce the density of the This unit is subject to severe slumping. Road failure and overstory canopy and increase the production of landslides are likely to occur after road construction. understory vegetation. Areas that support a large amount Slumping can be minimized by constructing logging roads of competing vegetation can be improved by prescribed in the less sloping areas, on better suited soils if practical, burning or by chemical or mechanical treatment. Seeding and by installing properly designed road drainage systems. disturbed areas to suitable plants increases forage Skid trails and unsurfaced roads may be impassable during production and reduces the risk of erosion. rainy periods. Logging roads require suitable surfacing for This unit is suited to the production of Douglas fir and year-round use. ponderosa pine. Other species that grow on this unit Undesirable plants limit natural or artificial reforestation include incense cedar and Pacific madrone. The unless intensive site preparation and maintenance understory vegetation includes oceanspray, tall measures are applied. Reforestation can be accomplished Oregongrape, and poison oak. by planting ponderosa pine seedlings. Mulching around On the basis of a 100-year site curve, the mean site seedlings helps to maintain the moisture supply in summer index for Douglas fir is 90. The yield at culmination of the and minimizes competition from undesirable understory mean annual increment is 4,200 cubic feet per acre in a plants. fully stocked, even-aged stand of trees at 60 years and A high temperature in the surface layer and an 31,840 board feet per acre (Scribner rule) at 160 years. On insufficient moisture supply in summer increase the the basis of a 50-year curve, the mean site index is 65. seedling mortality rate. To compensate for the expected On the basis of a 100-year site curve, the mean site high mortality rate, the larger seedlings or a greater number index for ponderosa pine is 90. The yield at culmination of seedlings should be planted. When the timber is harvested, leaving some of the larger trees unharvested provides shade for seedlings. The seasonal Permeability is moderate in the Brader soil. Available wetness increases the seedling mortality rate. Also, water capacity is about 2 inches. The effective rooting depth seedlings planted in the less fertile clayey subsoil grow is 12 to 20 inches. Runoff is slow or medium, and the poorly. hazard of water erosion is slight or moderate. The vegetative site is Douglas Fir Forest. This unit is used for hay and pasture, livestock grazing, and homesite development. 102B--Langellain-Brader loams, 1 to 7 percent This unit is suited to irrigated hay and pasture. It is slopes. This map unit is on knolls and ridges. Elevation is limited mainly by droughtiness; the depth to bedrock in the 1,300 to 3,200 feet. The mean annual precipitation is 18 to Brader soil; and, in the Langellain soil, the very slow 40 inches, the mean annual temperature is 48 to 54 permeability in the subsoil and wetness in winter and spring. degrees F, and the average frost-free period is 130 to 180 In summer, irrigation is needed for the maximum days. The native vegetation is mainly hardwoods and an production of hay and pasture. Sprinkler irrigation is the understory of grasses, shrubs, and forbs. best method of applying water. This method permits an This unit is about 55 percent Langellain soil and 20 even, controlled application of water, helps to prevent percent Brader soil. The components of this unit occur as excessive runoff, and minimizes the risk of erosion. Border areas so intricately intermingled that mapping them and contour flood irrigation systems also are suitable in the separately was not practical at the scale used. less sloping areas. For the efficient application and removal Included in this unit are small areas of Debenger and of surface irrigation water, land leveling is needed. If cuts Ruch soils, Carney and Selmac soils on concave slopes, are too deep, however, the bedrock or the clayey subsoil Coker and Gregory soils on concave slopes and near may be exposed. To prevent overirrigation and excessive drainageways, Kerby and Medford soils on terraces, and erosion or development of a perched water table, soils that are similar to the Brader soil but have bedrock applications of irrigation water should be adjusted to the within a depth of 12 inches. Also included are small areas available water capacity, the rate of water intake, and the of Langellain and Brader soils that have slopes of more needs of the crop. than 7 percent. Included areas make up about 25 percent Wetness limits the choice of suitable forage plants and of the total acreage. the period of cutting or grazing and increases the risk of The Langellain soil is moderately deep and moderately winterkill. Proper stocking rates, pasture rotation, and well drained. It formed in colluvium and alluvium derived restricted grazing during wet periods help to keep pastures dominantly from sedimentary rock. Typically, the surface is in good condition and protect the soils from erosion. covered with a layer of grasses, twigs, and leaves about 1/2 Grazing when the soils are wet results in compaction of the inch thick. The surface layer is dark reddish brown loam surface layer, poor tilth, and excessive runoff. Periodic about 6 inches thick. The next layer is dark brown loam mowing and clipping help to maintain uniform plant growth, about 4 inches thick. The upper 11 inches of the subsoil is discourage selective grazing, and reduce the extent of strong brown loam. The lower 17 inches is brown and clumpy growth. yellowish brown clay. Weathered bedrock is at a depth of The ability of tile drains to remove subsurface water is about 38 inches. The depth to bedrock ranges from 20 to limited because of the very slow permeability in the subsoil 40 inches. of the Langellain soil and the lack of suitable outlets. Land Permeability is moderate to a depth of 21 inches in the smoothing and open ditches can reduce surface wetness. Langellain soil and very slow below that depth. Available Fertilizer is needed to ensure the optimum growth of water capacity is about 4 inches. The effective rooting grasses and legumes. Grasses respond to nitrogen, and depth is limited by the layer of dense clay in the subsoil. legumes respond to sulfur and phosphorus. This layer is at a depth of 12 to 28 inches. Runoff is slow, The main limitations affecting livestock grazing are and the hazard of water erosion is slight. The water table, compaction and droughtiness. The Langellain soil also is which is perched above the layer of clay, is at a depth of limited by wetness in winter and spring and the Brader soil 0.5 foot to 2.0 feet from December through May. by the depth to bedrock. The vegetation suitable for The Brader soil is shallow and well drained. It formed in grazing includes Idaho fescue, bluebunch wheatgrass, colluvium derived dominantly from sedimentary rock. and pine bluegrass. If the range is overgrazed, the Typically, the surface layer is dark brown loam about 6 proportion of preferred forage plants decreases and the inches thick. The subsoil is dark reddish brown loam about proportion of less preferred forage, plants increases. 7 inches thick. Weathered bedrock is at a depth of about 13 inches. The depth to bedrock ranges from 12 to 20 inches. The Langellain soil remains wet for long periods in 102D-Langellain-Brader loams, 7 to 15 percent spring; therefore, grazing should be delayed until the more slopes. This map unit is on knolls and ridges. Elevation is desirable forage plants have achieved enough growth to 1,300 to 3,200 feet. The mean annual precipitation is 18 to withstand grazing pressure and the soil is firm enough to 40 inches, the mean annual temperature is 48 to 54 withstand trampling by livestock. Compaction can be degrees F, and the average frost-free period is 130 to 180 minimized by grazing first in the areas that dry out earliest. days. The native vegetation is mainly hardwoods and an Range seeding is suitable if the site is in poor condition. understory of grasses, shrubs, and forbs. The main limitations affecting seeding are the wetness of This unit is about 55 percent Langellain soil and 25 the Langellain soil in winter and spring, the depth to percent Brader soil. The components of this unit occur as bedrock in the Brader soil, and droughtiness in both soils. areas so intricately intermingled that mapping them The plants selected for seeding should be those that meet separately was not practical at the scale used. the seasonal requirements of livestock or wildlife, or both. Included in this unit are small areas of Carney and Suitable management practices on this unit include Selmac soils on concave slopes, Coker and Gregory soils proper grazing use, deferred grazing, rotation grazing, and near drainageways, Medford soils on terraces, Debenger brush control. Areas that support a large amount of and Ruch soils, and soils that are similar to the Brader soil competing vegetation can be improved by chemical or but have bedrock within a depth of 12 inches. Also included mechanical treatment. are small areas of Langellain and Brader soils that have This unit is limited as a site for livestock watering slopes of less than 7 or more than 15 percent. Included ponds and other water impoundments because of the areas make up about 20 percent of the total acreage. depth to bedrock. The Langellain soil is moderately deep and moderately The main limitations affecting homesite development well drained. It formed in colluvium and alluvium derived are the wetness, a high shrink -swell potential, the very dominantly from sedimentary rock. Typically, the surface is slow permeability, and the depth to bedrock. covered with a layer of grasses, twigs, and leaves about 1/2 This unit is poorly suited to standard systems of waste inch thick. The surface layer is dark reddish brown loam disposal because of the wetness, the very slow about 6 inches thick. The next layer is dark brown loam permeability, and the depth to bedrock. Alternative waste about 4 inches thick. The upper 11 inches of the subsoil is disposal systems may function properly on this unit. strong brown loam. The lower 17 inches is brown and Suitable included soils are throughout the unit. Onsite yellowish brown clay. Weathered bedrock is at a depth of investigation is needed to locate such soils. about 38 inches. The depth to bedrock ranges from 20 to 40 Because the seasonal high water table is perched above inches. the layer of clay, a drainage system is needed on sites for Permeability is moderate to a depth of 21 inches in the buildings with basements and crawl spaces. The wetness Langellain soil and very slow below that depth. Available can be reduced by installing drainage tile around footings. If water capacity is about 4 inches. The effective rooting depth buildings are constructed on the Langellain soil, properly is limited by the layer of dense clay in the subsoil. This layer designing foundations and footings, diverting runoff away is at a depth of 12 to 28 inches. Runoff is medium, and the from the buildings, and backfilling with material that has a hazard of water erosion is moderate. The water table, which low shrink -swell potential help to prevent the structural is perched above the layer of clay, is at a depth of 0.5 foot to damage caused by shrinking and swelling. Properly 2.0 feet from December through May. designing buildings and roads helps to offset the limited The Brader soil is shallow and well drained. It formed in ability of the Langellain soil to support a load. colluvium derived dominantly from sedimentary rock. Cuts needed to provide essentially level building sites Typically, the surface layer is dark brown loam about 6 can expose bedrock. Revegetating as soon as possible inches thick. The subsoil is dark reddish brown loam about helps to control erosion in disturbed areas around 7 inches thick. Weathered bedrock is at a depth of about 13 construction sites. Topsoil can be stockpiled and used to inches. The depth to bedrock ranges from 12 to 20 inches. reclaim areas disturbed during construction. Because of a Permeability is moderate in the Brader soil. Available low amount of rainfall in summer, irrigation is needed in water capacity is about 2 inches. The effective rooting areas that support lawn grasses, shrubs, vines, shade trees, depth is 12 to 20 inches. Runoff is medium, and the hazard or ornamental trees. of water erosion is moderate. The vegetative site is Loamy Hills, 20- to 35-inch This unit is used for hay and pasture, livestock precipitation zone. grazing, and homesite development. This unit is suited to irrigated hay and pasture. It is limited mainly by droughtiness, the slope, and the depth to condition. The main limitations are the wetness of the bedrock in the Brader soil. The Langellain soil also is limited Langellain soil in winter and spring, the depth to bedrock by the very slow permeability in the subsoil and wetness in in the Brader soil, and droughtiness in both soils. The winter and spring. plants selected for seeding should be those that meet the In summer, irrigation is needed for the maximum seasonal requirements of livestock or wildlife, or both. production of hay and pasture. Sprinkler irrigation is the This unit is limited as a site for livestock watering best method of applying water. This method permits an ponds and other water impoundments because of the even, controlled application of water, helps to prevent depth to bedrock. excessive runoff, and minimizes the risk of erosion. To The main limitations affecting homesite development are prevent overirrigation and excessive erosion or the wetness, a high shrink-swell potential, the depth to development of a perched water table, applications of bedrock, and the very slow permeability in the Langellain irrigation water should be adjusted to the available water soil. capacity, the rate of water intake, and the needs of the This unit is poorly suited to standard systems of waste crop. disposal because of the wetness, the very slow Wetness limits the choice of suitable forage plants and permeability, and the depth to bedrock. Alternative waste the period of cutting or grazing and increases the risk of disposal systems may function properly on this unit. winterkill. Proper stocking rates, pasture rotation, and Suitable included soils are throughout the unit. Onsite restricted grazing during wet periods help to keep pastures investigation is needed to locate such soils. in good condition and protect the soils from erosion. Because the seasonal high water table is perched above Grazing when the soils are wet results in compaction of the the layer of clay, a drainage system is needed on sites for surface layer, poor tilth, and excessive runoff. Periodic buildings with basements and crawl spaces. The wetness mowing and clipping help to maintain uniform plant growth, can be reduced by installing drainage tile around footings. If discourage selective grazing, and reduce the extent of buildings are constructed on the Langellain soil, properly clumpy growth. designing foundations and footings, diverting runoff away The ability of tile drains to remove subsurface water is from the buildings, and backfilling with material that has a limited because of the slope, the very slow permeability in low shrink -swell potential help to prevent the structural the subsoil of the Langellain soil, and the lack of suitable damage caused by shrinking and swelling. Properly outlets. Wetness can be reduced by interceptor drains. designing buildings and roads helps to offset the limited Fertilizer is needed to ensure the optimum growth of ability of the Langellain soil to support a load. grasses and legumes. Grasses respond to nitrogen, and Cuts needed to provide essentially level building sites legumes respond to sulfur and phosphorus. can expose bedrock. Revegetating as soon as possible The main limitations affecting livestock grazing are helps to control erosion in disturbed areas around compaction, erosion, and droughtiness. The Langellain soil construction sites. Topsoil can be stockpiled and used to also is limited by wetness in winter and spring and the reclaim areas disturbed during construction. In many areas it Brader soil by the depth to bedrock. The vegetation may be necessary to haul in topsoil for lawns and gardens. suitable for grazing includes Idaho fescue, bluebunch Because of a low amount of rainfall in summer, irrigation is wheatgrass, and pine bluegrass. If the range is needed in areas that support lawn grasses, shrubs, vines, overgrazed, the proportion of preferred forage plants shade trees, or ornamental trees. decreases and the proportion of less preferred forage The vegetative site is Loamy Hills, 20- to 35-inch plants increases. precipitation zone. The Langellain soil remains wet for long periods in spring. As a result, grazing should be delayed until the 103E-Langellain-Brader loams, 15 to 40 percent more desirable forage plants have achieved enough growth south slopes. This map unit is on hillslopes. Elevation is to withstand grazing pressure and the soil is firm enough to 1,300 to 3,200 feet. The mean annual precipitation is 18 to withstand trampling by livestock. Compaction can be 40 inches, the mean annual temperature is 48 to 54 minimized by grazing first in the areas that dry out earliest. degrees F, and the average frost-free period is 130 to 180 Suitable management practices on this unit include days. The native vegetation is mainly hardwoods and an proper grazing use, deferred grazing, rotation grazing, and understory of grasses, shrubs, and forbs. brush control. Areas that support a large amount of This unit is about 50 percent Langellain soil and 30 competing vegetation can be improved by chemical or percent Brader soil. The components of this unit occur as mechanical treatment. areas so intricately intermingled that mapping them Range seeding is suitable if the site is in poor separately was not practical at the scale used. growth to withstand grazing pressure and the soil is firm Included in this unit are small areas of Debenger soils, enough to withstand trampling by livestock. Compaction can Carney and Selmac soils on concave slopes, Ruch and be minimized by grazing first in the areas that dry out Manita soils on foot slopes, and soils that are similar to the earliest. Brader soil but have more than 35 percent rock fragments Range seeding is suitable if the site is in poor condition. or have bedrock within a depth of 12 inches. Also included The main limitations are the depth to bedrock in the Brader are small areas of Langellain and Brader soils that have soil, the wetness of the Langellain soil in winter and spring, slopes of less than 15 or more than 40 percent. Included and droughtiness and the slope in areas of both soils. The areas make up about 20 percent of the total acreage. plants selected for seeding should be those that meet the The Langellain soil is moderately deep and moderately seasonal requirements of livestock or wildlife, or both. well drained. It formed in colluvium and alluvium derived Suitable management practices on this unit include dominantly from sedimentary rock. Typically, the surface is proper grazing use, deferred grazing, rotation grazing, and covered with a layer of grasses, twigs, and leaves about 1/2 brush control. Areas that support a large amount of inch thick. The surface layer is dark reddish brown loam competing vegetation can be improved by chemical or about 6 inches thick. The next layer is dark brown loam mechanical treatment. In places the use of ground about 4 inches thick. The upper 11 inches of the subsoil is equipment and access by livestock are limited by the slope. strong brown loam. The lower 17 inches is brown and Constructing trails or walkways allows livestock to graze in yellowish brown clay. Weathered bedrock is at a depth of areas where access is limited. about 38 inches. The depth to bedrock ranges from 20 to 40 This unit is limited as a site for livestock watering inches. ponds and other water impoundments because of the Permeability is moderate to a depth of 21 inches in the slope and the depth to bedrock. Langellain soil and very slow below that depth. Available The vegetative site is Loamy Hills, 20- to 35-inch water capacity is about 4 inches. The effective rooting depth precipitation zone. is limited by the layer of dense clay in the subsoil. This layer is at a depth of 12 to 28 inches. Runoff is medium or rapid, 104E-Lettia sandy loam, 12 to 35 percent north and the hazard of water erosion is moderate or high. The slopes. This deep, well drained soil is on hillslopes. It water table, which is perched above the layer of clay, is at a formed in colluvium and residuum derived from granitic depth of 0.5 foot to 2.0 feet from December through May. rock. Elevation is 1,800 to 4,000 feet. The mean annual The Brader soil is shallow and well drained. It formed in precipitation is 45 to 60 inches, the mean annual colluvium derived dominantly from sandstone. Typically, the temperature is 45 to 50 degrees F, and the average surface layer is dark brown loam about 6 inches thick. The frost-free period is 100 to 160 days. The native vegetation subsoil is dark reddish brown loam about 7 inches thick. is mainly conifers and hardwoods and an understory of Weathered bedrock is at a depth of about 13 inches. The grasses, shrubs, and forbs. depth to bedrock ranges from 12 to 20 inches. Typically, the surface is covered with a layer of needles, Permeability is moderate in the Brader soil. Available leaves, and twigs about 2 inches thick. The surface layer is water capacity is about 2 inches. The effective rooting dark brown sandy loam about 3 inches thick. The next depth is 12 to 20 inches. Runoff is medium or rapid, and layer is brown and reddish brown loam about 11 inches the hazard of water erosion is moderate or high. thick. The upper 12 inches of the subsoil is red clay loam. This unit is used for livestock grazing and wildlife The lower 29 inches is red loam. Weathered bedrock is at habitat. The main limitations affecting livestock grazing are a depth of about 55 inches. The depth to bedrock ranges compaction, erosion, droughtiness, and the slope. The from 40 to 60 inches. In some areas the surface layer is Langellain soil also is limited by wetness in winter and clay loam. spring and the Brader soil by the depth to bedrock. The Included in this unit are small areas of Acker, Dumont, vegetation suitable for grazing includes Idaho fescue, Goolaway, and Musty soils; Steinmetz soils on the more bluebunch wheatgrass, and pine bluegrass. If the range is sloping parts of the landscape; poorly drained soils near overgrazed, the proportion of preferred forage plants drainageways and on concave slopes; soils that are similar decreases and the proportion of less preferred forage to the Lettia soil but have bedrock at a depth of more than plants increases. 60 inches; and, on ridges and convex slopes, soils that are The Langellain soil remains wet for long periods in similar to Steinmetz and Lettia soils but have bedrock within spring. As a result, grazing should be delayed until the a depth of 40 inches. Also included are small areas of Lettia more desirable forage plants have achieved enough soils that have slopes of less than 12 or more than 35 percent. Included areas make up about 20 percent of the total be accomplished by planting Douglas fir seedlings. acreage. Mulching around seedlings helps to maintain the moisture Permeability is moderately slow in the Lettia soil. supply in summer and minimizes competition from Available water capacity is about 8 inches. The effective undesirable understory plants. rooting depth is 40 to 60 inches. Runoff is medium, and the A high temperature in the surface layer and an hazard of water erosion is moderate or high. insufficient moisture supply in summer increase the This unit is used for timber production and wildlife seedling mortality rate. To compensate for the expected habitat. It is suited to the production of Douglas fir. Other high mortality rate, the larger seedlings or a greater number species that grow on this unit include incense cedar, of seedlings should be planted. When the timber is western hemlock, and Pacific madrone. The understory harvested, leaving some of the larger trees unharvested vegetation includes golden chinkapin, salal, and cascade provides shade for seedlings. Oregongrape. Increased erosion, loss of plant nutrients, and water On the basis of a 100-year site curve, the mean site repellency are likely to result from fires of moderate index for Douglas fir is 140. The yield at culmination of the intensity. mean annual increment is 8,700 cubic feet per acre in a The vegetative site is Mixed Fir-Salal (rhododendron) fully stocked, even-aged stand of trees at 60 years and Forest. 48,300 board feet per acre (Scribner rule) at 140 years. On the basis of a 50-year curve, the mean site index is 105. 105E-Lettia sandy loam, 12 to 35 percent south The main limitations affecting timber production are slopes. This deep, well drained soil is on hillslopes. It erosion, compaction, plant competition, and seedling formed in colluvium and residuum derived from granitic mortality. When timber is harvested, management that rock. Elevation is 1,800 to 4,000 feet. The mean annual minimizes the risk of erosion is essential. Wheeled and precipitation is 45 to 60 inches, the mean annual tracked logging equipment can be used in the less sloping temperature is 45 to 50 degrees F, and the average areas, but cable yarding generally is safer in the more frost-free period is 100 to 160 days. The native vegetation sloping areas and results in less surface disturbance. Using is mainly conifers and hardwoods and an understory of standard wheeled and tracked equipment when the soil is grasses, shrubs, and forbs. moist causes rutting and compaction. Puddling can occur Typically, the surface is covered with a layer of needles, when the soil is wet. Using low-pressure ground equipment leaves, and twigs about 2 inches thick. The surface layer is causes less damage to the soil and helps to maintain dark brown sandy loam about 3 inches thick. The next productivity. Compaction can be minimized by using layer is brown and reddish brown loam about 11 inches suitable methods of harvesting, laying out skid trails in thick. The upper 12 inches of the subsoil is red clay loam. advance, and harvesting timber when the soil is least The lower 29 inches is red loam. Weathered bedrock is at susceptible to compaction. Ripping skid trails and landings a depth of about 55 inches. The depth to bedrock ranges when the soil is dry can improve the growth of plants. from 40 to 60 inches. In some areas the surface layer is Properly designed road drainage systems that include clay loam. carefully located culverts help to control erosion. Areas that Included in this unit are small areas of Acker, Dumont, have been cut and filled are easily eroded unless they are Goolaway, and Musty soils; Steinmetz soils on the more treated. Seeding, mulching, and benching these areas help sloping parts of the landscape; poorly drained soils near to control erosion. Steep yarding paths, skid trails, and drainageways and on concave slopes; soils that are similar firebreaks are subject to rilling and gullying unless they are to the Lettia soil but have bedrock at a depth of more than protected by a plant cover or adequate water bars, or both. 60 inches; and, on ridges and convex slopes, soils that are Cutbanks occasionally slump when the soil is saturated. similar to the Lettia soil but have bedrock within a depth of This unit is subject to slumping, especially in areas 40 inches. Also included are small areas of Lettia soils that adjacent to drainageways. Road failure and landslides are have slopes of less than 12 or more than 35 percent. likely to occur after road construction and clearcutting. Skid Included areas make up about 20 percent of the total trails and unsurfaced roads may be impassable during acreage. rainy periods. Logging roads require suitable surfacing for Permeability is moderately slow in the Lettia soil. year-round use. Available water capacity is about 8 inches. The effective Undesirable plants limit natural or artificial rooting depth is 40 to 60 inches. Runoff is medium, and the reforestation unless intensive site preparation and hazard of water erosion is moderate or high. maintenance measures are applied. Reforestation can This unit is used for timber production and wildlife habitat. It is suited to the production of Douglas fir. Other species that grow on this unit include incense cedar, sugar pine, and Pacific madrone. The understory vegetation includes golden chinkapin, Whipplevine, and summer and minimizes competition from undesirable cascade Oregongrape. understory plants. On the basis of a 100-year site curve, the mean site Increased erosion, loss of plant nutrients, and water index for Douglas fir is 130. The yield at culmination of the repellency are likely to result from fires of moderate mean annual increment is 7,740 cubic feet per acre in a intensity. fully stocked, even-aged stand of trees at 60 years and The vegetative site is Douglas Fir-Madrone- 58,520 board feet per acre (Scribner rule) at 110 years. On Chinkapin Forest. the basis of a 50-year curve, the mean site index is 100. The main limitations affecting timber production are 106C-Lobert sandy loam, 0 to 12 percent slopes. erosion, compaction, seedling mortality, and plant This very deep, well drained soil is on stream terraces. It competition. When timber is harvested, management that formed in alluvial and lacustrine sediment derived minimizes the risk of erosion is essential. Wheeled and dominantly from tuff and volcanic ash. Elevation is 4,200 to tracked logging equipment can be used in the less sloping 4,400 feet. The mean annual precipitation is 16 to 18 areas, but cable yarding generally is safer in the more inches, the mean annual temperature is 43 to 45 degrees F, sloping areas and results in less surface disturbance. Using and the average frost-free period is less than 100 days. The standard wheeled and tracked equipment when the soil is native vegetation is mainly conifers and an understory of moist causes rutting and compaction. Puddling can occur grasses, shrubs, and forbs. when the soil is wet. Using low-pressure ground equipment Typically, the surface is covered with a layer of needles causes less damage to the soil and helps to maintain and twigs about 2 inches thick. The surface layer is dark productivity. Compaction can be minimized by using suitable reddish brown sandy loam about 20 inches thick. The upper methods of harvesting, laying out skid trails in advance, and 21 inches of the subsoil is dark reddish brown loam. The harvesting timber when the soil is least susceptible to lower part to a depth of 60 inches is dark brown loam. The compaction. Ripping skid trails and landings when the soil is depth to bedrock is 60 inches or more. dry can improve the growth of plants. Included in this unit are small areas of Kanutchan, Properly designed road drainage systems that include Pokegema, and Woodcock soils and soils that are similar to carefully located culverts help to control erosion Seeding, the Lobert soil but have bedrock within a depth of 60 inches mulching, and benching areas that have been cut and filled or are poorly drained. Also included are small areas of also help to control erosion. Steep yarding paths, skid trails, Lobert soils that have slopes of more than 12 percent. and firebreaks are subject to rilling and gullying unless they Included areas make up about 10 percent of the total are protected by a plant cover or adequate water bars, or acreage. both. Cutbanks occasionally slump when the soil is Permeability is moderate in the Lobert soil. Available saturated. water capacity is about 9 inches. The effective rooting This unit is subject to slumping, especially in areas depth is 60 inches or more. Runoff is slow, and the hazard adjacent to drainageways. Road failure and landslides are of water erosion is slight. likely to occur after road construction and clearcutting. Skid This unit is used for timber production, livestock trails and unsurfaced roads may be impassable during grazing, and wildlife habitat. rainy periods. Logging roads require suitable surfacing for This unit is suited to the production of ponderosa year-round use. pine. The understory vegetation includes antelope A high temperature in the surface layer and an bitterbrush, Pacific serviceberry, and Idaho fescue. insufficient moisture supply in summer increase the On the basis of a 100-year site curve, the mean site seedling mortality rate. To compensate for the expected index for ponderosa pine is 80. The yield at culmination of high mortality rate, the larger seedlings or a greater number the mean annual increment is 2,670 cubic feet per acre in a of seedlings should be planted. When the timber is fully stocked, even-aged stand of trees at 40 years and harvested, leaving some of the larger trees unharvested 33,750 board feet per acre (Scribner rule) at 150 years. provides shade for seedlings. Reforestation can be The main limitations affecting timber production are accomplished by planting Douglas fir and ponderosa pine compaction, erosion, and seedling mortality. Conventional seedlings. methods of harvesting timber generally are suitable, but the Undesirable plants limit natural or artificial soil may be compacted if it is moist when heavy equipment reforestation unless intensive site preparation and is used. Puddling can occur when the soil is wet. Using maintenance measures are applied. Mulching around low-pressure ground equipment causes less damage to the seedlings helps to maintain the moisture supply in soil and helps to maintain productivity. Compaction can be minimized by using suitable methods of harvesting, laying out skid trails 120 days. The native vegetation is mainly grasses, in advance, and harvesting timber when the soil is least shrubs, and forbs and a few scattered hardwoods and susceptible to compaction. Ripping skid trails and landings conifers. when the soil is dry can improve the growth of plants. This unit is about 55 percent Lorella soil and 25 percent Erosion can be controlled by carefully planning the Skookum soil. The components of this unit occur as areas construction and maintenance of logging roads, skid trails, so intricately intermingled that mapping them separately and landings. Seeding, mulching, and benching areas that was not practical at the scale used. have been cut and filled also help to control erosion. Skid Included in this unit are small areas of Paragon soils, trails and unsurfaced roads may be impassable during Rock outcrop on ridges and convex slopes, soils that are rainy periods. Logging roads require suitable surfacing for similar to the Lorella soil but have bedrock within a depth of year-round use. 12 inches, and soils that are similar to the Skookum soil but Severe frost can damage or kill seedlings. Air have bedrock at a depth of more than 40 inches. Also drainage may be restricted on this unit. Proper timber included are small areas of Lorella and Skookum soils that harvesting methods can reduce the effect of frost on have slopes of less than 15 or more than 35 percent. regeneration. Reforestation can be accomplished by Included areas make up about 20 percent of the total planting ponderosa pine seedlings. acreage. A high temperature in the surface layer and an The Lorella soil is shallow and well drained. It formed in insufficient moisture supply in summer increase the residuum and colluvium derived dominantly from andesite, seedling mortality rate. To compensate for the expected tuff, and breccia. Typically, the surface layer is very dark high mortality rate, the larger seedlings or a greater number brown extremely stony loam about 5 inches thick. The of seedlings should be planted. When the timber is subsoil is very dark brown and dark brown very cobbly clay harvested, leaving some of the larger trees unharvested loam about 12 inches thick. Bedrock is at a depth of about provides shade for seedlings. 17 inches. The depth to bedrock ranges from 12 to 20 The main limitation affecting livestock grazing is inches. compaction. The native vegetation suitable for grazing Permeability is slow in the Lorella soil. Available includes Idaho fescue, bluebunch wheatgrass, and western water capacity is about 1 inch. The effective rooting needlegrass. If the understory is overgrazed, the proportion depth is 12 to 20 inches. Runoff is medium, and the of preferred forage plants decreases and the proportion of hazard of water erosion is moderate. less preferred forage plants increases. The Skookum soil is moderately deep and well drained. It A planned grazing system that includes timely deferment formed in residuum and colluvium derived dominantly from of grazing, rotation grazing, and proper livestock distribution andesite, tuff, and breccia. Typically, the surface layer is helps to prevent overgrazing of the understory and damage very dark brown very cobbly loam about 3 inches thick. The to the soil. Grazing should be delayed until the more next layer is very dark grayish brown very cobbly loam about desirable forage plants have achieved enough growth to 5 inches thick. The upper 8 inches of the subsoil is very dark withstand grazing pressure and the soil is firm enough to grayish brown very cobbly clay loam. The lower 12 inches is withstand trampling by livestock. dark brown very cobbly and extremely cobbly clay. Bedrock Thinning, logging, and fire reduce the density of the is at a depth of about 28 inches. The depth to bedrock overstory canopy and increase the production of ranges from 20 to 40 inches. In some areas the surface understory vegetation. Areas that support a large amount layer is stony. of competing vegetation can be improved by prescribed Permeability is slow in the Skookum soil. Available burning or by chemical or mechanical treatment. Seeding water capacity is about 2 inches. The effective rooting disturbed areas to suitable plants increases forage depth is 20 to 40 inches. Runoff is medium, and the production and reduces the risk of erosion. hazard of water erosion is moderate. The vegetative site is Deep Loamy, 16- to 20-inch This unit is used for livestock grazing and wildlife habitat. precipitation zone. The main limitations affecting livestock grazing are compaction, erosion, the stones and cobbles on the 107E-Lorella-Skookum complex, 15 to 35 percent surface, and droughtiness. The Lorella soil also is limited by slopes. This map unit is on hillslopes. Elevation is 3,800 to the depth to bedrock. The vegetation suitable for grazing 4,800 feet. The mean annual precipitation is 18 to 20 includes Idaho fescue, bluebunch wheatgrass, and pine inches, the mean annual temperature is 45 to 51 degrees F, bluegrass. If the range is overgrazed, the proportion of arid the average frost-free period is 100 to preferred forage plants decreases and the proportion of less preferred forage plants increases. Grazing should be delayed until the more desirable forage plants have achieved enough for timber production, pasture, or homesite growth to withstand grazing pressure and the soils are development. firm enough to withstand trampling by livestock. This unit is well suited to irrigated crops. It is limited Suitable management practices on this unit include mainly by the moderately slow permeability. In summer, proper grazing use, deferred grazing, rotation grazing, and irrigation is needed for the maximum production of most brush control. Areas that support a large amount of crops. Furrow, border, corrugation, trickle, and sprinkler competing vegetation can be improved by chemical or irrigation systems are suitable. The system used generally is mechanical treatment. Because of the stones and cobbles governed by the crop that is grown. For the efficient on the surface and the included areas of Rock outcrop, the application and removal of surface irrigation water, land use of equipment is impractical. leveling is needed. To prevent overirrigation and excessive This unit is poorly suited to range seeding. The main erosion, applications of irrigation water should be adjusted limitations are droughtiness, the stones and cobbles on the to the available water capacity, the rate of water intake, and surface, and the depth to bedrock in the Lorella soil. The the needs of the crop. The use of pipe, ditch lining, or drop plants selected for seeding should be those that meet the structures in irrigation ditches reduces water loss and the seasonal requirements of livestock or wildlife, or both. hazard of erosion. This unit is limited as a site for livestock watering Returning all crop residue to the soil and using a ponds and other water impoundments because of the cropping system that includes grasses, legumes, or slope and the depth to bedrock. grass-legume mixtures help to maintain fertility and tilth. The vegetative site is Droughty Slopes, 20- to 30- Leaving crop residue on or near the surface helps to inch precipitation zone. conserve moisture and control erosion. A tillage pan forms easily if the soil is tilled when wet. 108B-Manita loam, 2 to 7 percent slopes. This Chiseling or subsoiling breaks up the pan. Surface crusting deep, well drained soil is on alluvial fans. It formed in and compaction can be minimized by returning crop residue alluvium derived dominantly from metamorphic rock. to the soil. Elevation is 1,000 to 4,000 feet. The mean annual Proper stocking rates, pasture rotation, and restricted precipitation is 20 to 40 inches, the mean annual grazing during wet periods help to keep pastures in good temperature is 47 to 54 degrees F, and the average condition and protect the soil from erosion. Grazing when frost-free period is 100 to 170 days. The native the soil is wet results in compaction of the surface layer, vegetation is mainly conifers and hardwoods and an poor tilth, and excessive runoff. Periodic mowing and understory of grasses, shrubs, and forbs. clipping help to maintain uniform plant growth, discourage Typically, the surface layer is dark brown loam about 8 selective grazing, and reduce the extent of clumpy growth. inches thick. The upper 5 inches of the subsoil is dark Fertilizer is needed to ensure the optimum growth of reddish brown clay loam. The lower 45 inches is yellowish grasses and legumes. Grasses respond to nitrogen, and red clay loam. Weathered bedrock is at a depth of about 58 legumes respond to sulfur and phosphorus. inches. The depth to bedrock ranges from 40 to 60 inches. Solid-set sprinkler irrigation is the best method of In some areas the surface layer is gravelly. controlling frost and providing adequate moisture for tree Included in this unit are small areas of Ruch soils, Darow fruit. Compaction can be minimized by limiting the use of and Vannoy soils on convex slopes, Selmac soils on equipment when the soil is wet. A permanent cover crop concave slopes, Gregory and Medford soils near helps to control runoff and erosion. drainageways and on terraces, and soils that are similar to This unit is well suited to homesite development. The the Manita soil but have bedrock at a depth of more than 60 main limitations are the moderately slow permeability and inches. Also included are small areas of Manita soils that the shrink-swell potential. The moderately slow permeability have slopes of more than 7 percent. Included areas make can be overcome by increasing the size of the absorption up about 20 percent of the total acreage. field. Permeability is moderately slow in the Manita soil. If buildings are constructed on this unit, properly Available water capacity is about 8 inches. The effective designing foundations and footings, diverting runoff away rooting depth is 40 to 60 inches. Runoff is slow, and the from the buildings, and backfilling with material that has a hazard of water erosion is slight. low shrink -swell potential help to prevent the structural This unit is used for irrigated crops, such as alfalfa hay, damage caused by shrinking and swelling. Properly small grain, and tree fruit. Other crops include corn for designing buildings and roads helps to offset the limited silage and grass-legume hay. Some areas are used ability of the soil to support a load. Revegetating as soon as possible helps to control erosion in disturbed areas around construction sites. Topsoil can be stockpiled and used to reclaim areas 108D-Manita loam, 7 to 20 percent slopes. This disturbed during construction. Because of a low amount of deep, well drained soil is on alluvial fans. It formed in rainfall in summer, irrigation is needed in areas that support alluvium derived dominantly from metamorphic rock. lawn grasses, shrubs, vines, shade trees, or ornamental Elevation is 1,000 to 4,000 feet. The mean annual trees. precipitation is 20 to 40 inches, the mean annual This unit is suited to the production of Douglas fir and temperature is 47 to 54 degrees F, and the average ponderosa pine. Other species that grow on this unit frost-free period is 100 to 170 days. The native include incense cedar, California black oak, and Pacific vegetation is mainly conifers and hardwoods and an madrone. The understory vegetation includes Pacific understory of grasses, shrubs, and forbs. serviceberry, tall Oregongrape, and California fescue. Typically, the surface layer is dark brown loam about 8 On the basis of a 100-year site curve, the mean site inches thick. The upper 5 inches of the subsoil is dark index for Douglas fir is 105. The yield at culmination of the reddish brown clay loam. The lower 45 inches is yellowish mean annual increment is 5,460 cubic feet per acre in a red clay loam. Weathered bedrock is at a depth of about 58 fully stocked, even-aged stand of trees at 60 years and inches. The depth to bedrock ranges from 40 to 60 inches. 45,600 board feet per acre (Scribner rule) at 150 years. On In some areas the surface layer is gravelly. the basis of a 50-year curve, the mean site index is 75. Included in this unit are small areas of Ruch soils, Darow The main limitations affecting timber production are and Vannoy soils on ridges and convex slopes, Selmac compaction, seedling mortality, and plant competition. soils on concave slopes, Gregory and Medford soils near Conventional methods of harvesting timber generally are drainageways on terraces, and soils that are similar to the suitable, but the soil may be compacted if it is moist when Manita soil but have bedrock at a depth of more than 60 heavy equipment is used. Puddling can occur when the soil inches. Also included are small areas of Manita soils that is wet. Using low-pressure ground equipment causes less have slopes of less than 7 or more than 20 percent. damage to the soil and helps to maintain productivity. Included areas make up about 20 percent of the total Compaction can be minimized by using suitable methods of acreage. harvesting, laying out skid trails in advance, and harvesting Permeability is moderately slow in the Manita soil. timber when the soil is least susceptible to compaction. Available water capacity is about 8 inches. The effective Ripping skid trails and landings when the soil is dry can rooting depth is 40 to 60 inches. ,Runoff is slow or medium, improve the growth of plants. and the hazard of water erosion is slight or moderate. Erosion can be controlled by carefully planning the This unit is used for irrigated crops, such as alfalfa construction and maintenance of logging roads, skid trails, hay, small grain, tree fruit, and grass-legume hay. It also and landings. Seeding, mulching, and benching areas that is used for timber production, pasture, and homesite have been cut and filled also help to control erosion. Skid development. trails and unsurfaced roads may be impassable during This unit is suited to irrigated crops. It is limited mainly rainy periods. Logging roads require suitable surfacing for by the slope and the moderately slow permeability. In year-round use. summer, irrigation is needed for the maximum production of A high temperature in the surface layer and an most crops. Because of the slope, sprinkler irrigation is the insufficient moisture supply in summer increase the best method of applying water. This method permits an seedling mortality rate. To compensate for the expected even, controlled application of water, helps to prevent high mortality rate, the larger seedlings or a greater number excessive runoff, and minimizes the risk of erosion. To of seedlings should be planted. When the timber is prevent overirrigation and excessive erosion, applications harvested, leaving some of the larger trees unharvested of irrigation water should be adjusted to the available water provides shade for seedlings. Reforestation can be capacity, the rate of water intake, and the needs of the accomplished by planting Douglas fir and ponderosa pine crop. seedlings. Returning all crop residue to the soil and using a Undesirable plants limit natural or artificial cropping system that includes grasses, legumes, or reforestation unless intensive site preparation and grass-legume mixtures help to maintain fertility and tilth. maintenance measures are applied. Mulching around Leaving crop residue on or near the surface helps to seedlings helps to maintain the moisture supply in conserve moisture and control erosion. summer and minimizes competition from undesirable A tillage pan forms easily if the soil is tilled when wet. understory plants. Chiseling or subsoiling breaks up the pan. Surface The vegetative site is Pine-Douglas Fir-Fescue. crusting and compaction can be minimized by returning and 45,600 board feet per acre (Scribner rule) at 150 crop residue to the soil. years. On the basis of a 50-year curve, the mean site The hazard of erosion can be reduced if fall grain is index is 75. seeded early, tillage is minimized, and tillage and seeding The main limitations affecting timber production are are on the contour or across the slope. Also, waterways erosion, compaction, seedling mortality, and plant should be shaped and seeded to perennial grasses. competition. Conventional methods of harvesting timber Proper stocking rates, pasture rotation, and restricted generally are suitable, but the soil may be compacted if it is grazing during wet periods help to keep pastures in good moist when heavy equipment is used. Puddling can occur condition and protect the soil from erosion. Grazing when when the soil is wet. Using low-pressure ground equipment the soil is wet results in compaction of the surface layer, causes less damage to the soil and helps to maintain poor tilth, and excessive runoff. Periodic mowing and productivity. Compaction can be minimized by using clipping help to maintain uniform plant growth, discourage suitable methods of harvesting, laying out skid trails in selective grazing, and reduce the extent of clumpy growth. advance, and harvesting timber when the soil is least Fertilizer is needed to ensure the optimum growth of susceptible to compaction. Ripping skid trails and landings grasses and legumes. Grasses respond to nitrogen, and when the soil is dry can improve the growth of plants. legumes respond to sulfur and phosphorus. Erosion can be controlled by carefully planning the Solid-set sprinkler irrigation is the best method of construction and maintenance of logging roads, skid trails, controlling frost and providing adequate moisture for tree and landings. Seeding, mulching, and benching areas that fruit. Compaction can be minimized by limiting the use of have been cut and filled also help to control erosion. Skid equipment when the soil is wet. A permanent cover crop trails and unsurfaced roads may be impassable during helps to control runoff and erosion. rainy periods. Logging roads require suitable surfacing for The main limitations affecting homesite development year-round use. are the moderately slow permeability, the shrink -swell A high temperature in the surface layer and an potential, and the slope. The moderately slow permeability insufficient moisture supply in summer increase the can be overcome by increasing the size of the absorption seedling mortality rate. To compensate for the expected field. high mortality rate, the larger seedlings or a greater number If buildings are constructed on this unit, properly of seedlings should be planted. When the timber is designing foundations and footings, diverting runoff away harvested, leaving some of the larger trees unharvested from the buildings, and backfilling with material that has a provides shade for seedlings. Reforestation can be low shrink -swell potential help to prevent the structural accomplished by planting Douglas fir and ponderosa pine damage caused by shrinking and swelling. Properly seedlings. designing buildings and roads helps to offset the limited Undesirable plants limit natural or artificial ability of the soil to support a load. reforestation unless intensive site preparation and Erosion is a hazard on the steeper slopes. Only the maintenance measures are applied. Mulching around part of the site that is used for construction should be seedlings helps to maintain the moisture supply in disturbed. Revegetating as soon as possible helps to summer and minimizes competition from undesirable control erosion in disturbed areas around construction understory plants. sites. Topsoil can be stockpiled and used to reclaim areas The vegetative site is Pine-Douglas Fir-Fescue. disturbed during construction. Because of a low amount of rainfall in summer, irrigation is needed in areas that 108E-Manita loam, 20 to 35 percent slopes. This deep, support lawn grasses, shrubs, vines, shade trees, or well drained soil is on alluvial fans and hillslopes. It formed ornamental trees. in alluvium and colluvium derived dominantly from This unit is suited to the production of Douglas fir and metamorphic rock. Elevation is 1,000 to 4,000 feet. The ponderosa pine. Other species that grow on this unit mean annual precipitation is 20 to 40 inches, the mean include incense cedar, California black oak, and Pacific annual temperature is 47 to 54 degrees F, and the average madrone. The understory vegetation includes Pacific frost-free period is 100 to 170 days. The native vegetation is serviceberry, tall Oregongrape, and California fescue. mainly conifers and hardwoods and an understory of On the basis of a 100-year site curve, the mean site grasses, shrubs, and forbs. index for Douglas fir is 105. The yield at culmination of the Typically, the surface layer is dark brown loam about 8 mean annual increment is 5,460 cubic feet per acre in a inches thick. The upper 5 inches of the subsoil is dark fully stocked, even-aged stand of trees at 60 years reddish brown clay loam. The lower 45 inches is yellowish red clay loam. Weathered bedrock is at a depth of about 58 inches. The depth to bedrock ranges from 40 to 60 inches. In some areas the surface layer is shrubs, vines, shade trees, or ornamental trees. gravelly. This unit is suited to the production of Douglas fir and Included in this unit are small areas of Darow, Vannoy, ponderosa pine. Other species that grow on this unit and Voorhies soils on ridges and convex slopes, Selmac include incense cedar, California black oak, and Pacific soils on concave slopes, poorly drained soils near madrone. The understory vegetation includes Pacific drainageways and on concave slopes, Ruch soils on toe serviceberry, tall Oregongrape, and California fescue. slopes, and soils that are similar to the Manita soil but have On the basis of a 100-year site curve, the mean site bedrock at a depth of more than 60 inches. Also included index for Douglas fir is 105. The yield at culmination of the are small areas of Manita soils that have slopes of less than mean annual increment is 5,460 cubic feet per acre in a 20 or more than 35 percent. Included areas make up about fully stocked, even-aged stand of trees at 60 years and 20 percent of the total acreage. 45,600 board feet per acre (Scribner rule) at 150 years. On Permeability is moderately slow in the Manita soil. the basis of a 50-year curve, the mean site index is 75. Available water capacity is about 8 inches. The effective The main limitations affecting timber production are rooting depth is 40 to 60 inches. Runoff is medium, and the erosion, compaction, seedling mortality, and plant hazard of water erosion is moderate. competition. Wheeled and tracked logging equipment can This unit is used for hay and pasture, timber be used in the less sloping areas, but cable yarding production, and homesite development. generally is safer in the more sloping areas and results in The main limitations in the areas used for hay and less surface disturbance. Using standard wheeled and pasture are the slope, erosion, and compaction. Seedbeds tracked equipment when the soil is moist causes rutting and should be prepared on the contour or across the slope compaction. Puddling can occur when the soil is wet. Using where practical. Proper stocking rates, pasture rotation, and low-pressure ground equipment causes less damage to the restricted grazing during wet periods help to keep pastures soil and helps to maintain productivity. Compaction can be in good condition and protect the soil from erosion. Grazing minimized by using suitable methods of harvesting, laying when the soil is wet results in compaction of the surface out skid trails in advance, and harvesting timber when the layer, poor tilth, and excessive runoff. Periodic mowing and soil is least susceptible to compaction. Ripping skid trails clipping help to maintain uniform plant growth, discourage and landings when the soil is dry can improve the growth of selective grazing, and reduce the extent of clumpy growth. plants. Fertilizer is needed to ensure the optimum growth of Properly designed road drainage systems that include grasses and legumes. Grasses respond to nitrogen, and carefully located culverts help to control erosion. Seeding, legumes respond to sulfur and phosphorus. mulching, and benching areas that have been cut and filled The main limitations affecting homesite development are also help to control erosion. Steep yarding paths, skid trails, the slope, the moderately slow permeability, and the and firebreaks are subject to rilling and gullying unless they shrink-swell potential. The moderately slow permeability can are protected by a plant cover or adequate water bars, or be overcome by increasing the size of the absorption field. both. Skid trails and unsurfaced roads may be impassable Because of the slope, the absorption lines should be during rainy periods. Logging roads require suitable installed on the contour. surfacing for year-round use. If buildings are constructed on this unit, properly A high temperature in the surface layer and an designing foundations and footings, diverting runoff away insufficient moisture supply in summer result in a high from the buildings, and backfilling with material that has a seedling mortality rate, especially on south- and low shrink -swell potential help to prevent the structural southwest-facing slopes. To compensate for the expected damage caused by shrinking and swelling. Properly high mortality rate, the larger seedlings or a greater number designing buildings and roads helps to offset the limited of seedlings should be planted. When the timber is ability of the soil to support a load. harvested, leaving some of the larger trees unharvested The slope limits the use of the steeper parts of the provides shade for seedlings. Reforestation can be landscape for building site development because of the risk accomplished by planting Douglas fir and ponderosa pine of erosion. Only the part of the site that is used for seedlings. construction should be disturbed. Revegetating as soon as Undesirable plants limit natural or artificial possible helps to control erosion in disturbed areas around reforestation unless intensive site preparation and construction sites. Topsoil can be stockpiled and used to maintenance measures are applied. Mulching around reclaim areas disturbed during construction. Because of a seedlings helps to maintain the moisture supply in low amount of rainfall in summer, irrigation is needed in areas that support lawn grasses, summer and minimizes competition from undesirable wet. Using low-pressure ground equipment causes less understory plants. damage to the soil and helps to maintain productivity. The vegetative site is Pine-Douglas Fir-Fescue. Compaction can be minimized by using suitable methods of harvesting, laying out skid trails in advance, and harvesting 108F-Manita loam, 35 to 50 percent slopes. This timber when the soil is least susceptible to compaction. deep, well drained soil is on hillslopes. It formed in Ripping skid trails and landings when the soil is dry can colluvium derived dominantly from metamorphic rock. improve the growth of plants. Elevation is 1,000 to 4,000 feet. The mean annual Properly designed road drainage systems that include precipitation is 20 to 40 inches, the mean annual carefully located culverts help to control erosion. Seeding, temperature is 47 to 54 degrees F, and the average mulching, and benching areas that have been cut and filled frost-free period is 100 to 160 days. The native vegetation also help to control erosion. Steep yarding paths, skid trails, is mainly conifers and hardwoods and an understory of and firebreaks are subject to rilling and gullying unless they grasses, shrubs, and forbs. are protected by a plant cover or adequate water bars, or Typically, the surface layer is dark brown loam about 8 both. Cutbanks occasionally slump when the soil is inches thick. The upper 5 inches of the subsoil is dark saturated. reddish brown clay loam. The lower 45 inches is yellowish Constructing logging roads on the steeper parts of the red clay loam. Weathered bedrock is at a depth of about 58 landscape can result in a high risk of erosion. Material that inches. The depth to bedrock ranges from 40 to 60 inches. is discarded when the roads are built can damage In some areas the surface layer is gravelly or very gravelly. vegetation and is a potential source of sedimentation. If Included in this unit are small areas of Vannoy and the material becomes saturated, avalanches of debris can Voorhies soils, soils that are similar to the Manita soil but occur. End hauling of the waste material minimizes have bedrock at a depth of more than 60 inches, Ruch damage to the vegetation downslope and reduces the risk soils on toe slopes, Selmac soils on concave slopes, and of sedimentation. McMullin soils on ridges and on convex slopes. Also This unit is subject to slumping. Road failure and included are small areas of Manita soils that have slopes landslides are likely to occur after road construction and of less than 35 or more than 50 percent. Included areas clearcutting. Slumping can be minimized by constructing make up about 15 percent of the total acreage. logging roads in the less sloping areas, on better suited soils Permeability is moderately slow in the Manita soil. if practical, and by installing properly designed road Available water capacity is about 8 inches. The effective drainage systems. Skid trails and unsurfaced roads may be rooting depth is 40 to 60 inches. Runoff is rapid, and the impassable during rainy periods. Logging roads require hazard of water erosion is high. suitable surfacing for year-round use. This unit is used for timber production and wildlife A high temperature in the surface layer and an habitat. It is suited to the production of Douglas fir and insufficient moisture supply in summer result in a high ponderosa pine. Other species that grow on this unit seedling mortality rate, especially on south- and include incense cedar, California black oak, and Pacific southwest-facing slopes. To compensate for the expected madrone. The understory vegetation includes Pacific high mortality rate, the larger seedlings or a greater number serviceberry, tall Oregongrape, and California fescue. of seedlings should be planted. When the timber is On the basis of a 100-year site curve, the mean site harvested, leaving some of the larger trees unharvested index for Douglas fir is 105. The yield at culmination of the provides shade for seedlings. The seedling mortality rate mean annual increment is 5,460 cubic feet per acre in a also can be reduced on south- and southwest-facing slopes fully stocked, even-aged stand of trees at 60 years and by providing artificial shade for seedlings. Reforestation can 45,600 board feet per acre (Scribner rule) at 150 years. On be accomplished by planting Douglas fir and ponderosa the basis of a 50-year curve, the mean site index is 75. pine seedlings. The main limitations affecting timber production are the Undesirable plants limit natural or artificial slope, erosion, compaction, seedling mortality, and plant reforestation unless intensive site preparation and competition. Wheeled and tracked logging equipment can maintenance measures are applied. Mulching around be used in the less sloping areas, but cable yarding seedlings helps to maintain the moisture supply in generally is safer and results in less surface disturbance. summer and minimizes competition from undesirable Using standard wheeled and tracked equipment when the understory plants. soil is moist causes rutting and compaction. Puddling can The vegetative site is Pine-Douglas Fir-Fescue. occur when the soil is 109E-Manita-Vannoy complex, 20 to 40 percent slopes. This map unit is on alluvial fans and hillslopes. Elevation is 1,000 to 4,000 feet. The mean annual precipitation is 20 to 40 inches, the mean annual unit is not suitable for irrigation because of the slope. temperature is 47 to 54 degrees F, and the average Seedbeds should be prepared on the contour or across the frost-free period is 100 to 160 days. The native slope where practical. Proper stocking rates, pasture vegetation is mainly conifers and hardwoods and an rotation, and restricted grazing during wet periods help to understory of grasses, shrubs, and forbs. keep pastures in good condition and protect the soils from This unit is about 55 percent Manita soil and 35 percent erosion. Grazing when the soils are wet results in Vannoy soil. The components of this unit occur as areas so compaction of the surface layer, poor tilth, and excessive intricately intermingled that mapping them separately was runoff. Periodic mowing and clipping help to maintain not practical at the scale used. The Manita soil is commonly uniform plant growth, discourage selective grazing, and on the less sloping parts of the landscape. reduce the extent of clumpy growth. Fertilizer is needed to Included in this unit are small areas of Darow and ensure the optimum growth of grasses and legumes. Voorhies soils on ridges and convex slopes, Selmac soils on Grasses respond to nitrogen, and legumes respond to concave slopes, poorly drained soils near drainageways, sulfur and phosphorus. Ruch soils on toe slopes, and soils that are similar to the The main limitations affecting homesite development Manita soil but have bedrock at a depth of more than 60 are the depth to bedrock in the Vannoy soil, the shrink- inches. Also included are small areas of Manita soils that swell potential of the Manita soil, and the slope and have slopes of less than 20 or more than 40 percent. moderately slow permeability of both soils. The moderately Included areas make up about 10 percent of the total slow permeability can be overcome by increasing the size acreage. of the absorption field. Because of the slope, the The Manita soil is deep and well drained. It formed in absorption lines should be installed on the contour. The alluvium and colluvium derived dominantly from deeper and less sloping areas of the Vannoy soil may be metamorphic rock. Typically, the surface layer is dark suited to septic tank absorption fields. Onsite investigation brown loam about 8 inches thick. The upper 5 inches of the is needed to locate such areas. subsoil is dark reddish brown clay loam. The lower 45 The slope limits the use of the steeper areas of this unit inches is yellowish red clay loam. Weathered bedrock is at for building site development. Cuts needed to provide a depth of about 58 inches. The depth to bedrock ranges essentially level building sites can expose bedrock. If from 40 to 60 inches. In some areas the surface layer is buildings are constructed on the Manita soil, properly gravelly. designing foundations and footings, diverting runoff away Permeability is moderately slow in the Manita soil. from the buildings, and backfilling with material that has a Available water capacity is about 8 inches. The effective low shrink -swell potential help to prevent the structural rooting depth is 40 to 60 inches. Runoff is medium or rapid, damage caused by shrinking and swelling. Properly and the hazard of water erosion is moderate or high. designing buildings and roads helps to offset the limited The Vannoy soil is moderately deep and well drained. It ability of the Manita soil to support a load. formed in colluvium derived dominantly from metamorphic Erosion is a hazard on the steeper parts of the rock. Typically, the surface is covered with a layer of landscape. Only the part of the site that is used for needles, leaves, and twigs about 3/4 inch thick. The surface construction should be disturbed. Revegetating as soon as layer is dark brown silt loam about 4 inches thick. The next possible helps to control erosion in disturbed areas around layer is reddish brown silt loam about 7 inches thick. The construction sites. Topsoil can be stockpiled and used to subsoil is yellowish red clay loam about 27 inches thick. reclaim areas disturbed during construction. Because of a Weathered bedrock is at a depth of about 38 inches. The low amount of rainfall in summer, irrigation is needed in depth to bedrock ranges from 20 to 40 inches. In some areas that support lawn grasses, shrubs, vines, shade trees, areas the surface layer is gravelly or very gravelly. or ornamental trees. Permeability is moderately slow in the Vannoy soil. This unit is suited to the production of Douglas fir and Available water capacity is about 5 inches. The effective ponderosa pine. Other species that grow on this unit rooting depth is 20 to 40 inches. Runoff is medium or rapid, include incense cedar, California black oak, and Pacific and the hazard of water erosion is moderate or high. madrone. The understory vegetation includes Pacific This unit is used for hay and pasture, timber serviceberry, tall Oregongrape, and California fescue. production, and homesite development. On the basis of a 100-year site curve, the mean site The main limitations in the areas used for hay and index for Douglas fir is 105 on both the Manita and Vannoy pasture are the slope, erosion, and compaction. This soils. The yield at culmination of the mean annual increment is 5,460 cubic feet per acre in a fully southwest-facing slopes by providing artificial shade for stocked, even-aged stand of trees at 60 years and 45,600 seedlings. Reforestation can be accomplished by planting board feet per acre (Scribner rule) at 150 years. On the Douglas fir and ponderosa pine seedlings. basis of a 50-year curve, the mean site index is 75. Undesirable plants limit natural or artificial reforestation On the basis of a 100-year site curve, the mean site unless intensive site preparation and maintenance index for ponderosa pine is 90 on the Vannoy soil. The measures are applied. Mulching around seedlings helps yield at culmination of the mean annual increment is 3,400 to maintain the moisture supply in summer and minimizes cubic feet per acre in a fully stocked, even-aged stand of competition from undesirable understory plants. trees at 40 years and 37,960 board feet per acre (Scribner The vegetative site is Pine-Douglas Fir-Fescue. rule) at 130 years. The main limitations affecting timber production are 110E-McMullin gravelly loam, 3 to 35 percent slopes. erosion, compaction, the slope, seedling mortality, and This shallow, well drained soil is on hillslopes. It formed in plant competition. Also, the bedrock restricts root growth. colluvium derived dominantly from igneous and metamorphic As a result, windthrow is a hazard. rock. Elevation is 1,000 to 4,000 feet. The mean annual Wheeled and tracked logging equipment can be used in precipitation is 18 to 40 inches, the mean annual temperature the less sloping areas, but cable yarding generally is safer in is 45 to 52 degrees F, and the average frost-free period is the more sloping areas and results in less surface 100 to 180 days. The native vegetation is mainly grasses, disturbance. Using standard wheeled and tracked equipment shrubs, and forbs. when the soils are moist causes rutting and compaction. Typically, the surface layer is dark reddish brown gravelly Puddling can occur when the soils are wet. Using loam about 7 inches thick. The subsoil is dark reddish brown low-pressure ground equipment causes less damage to the gravelly clay loam about 10 inches thick. Bedrock is at a soils and helps to maintain productivity. Compaction can be depth of about 17 inches. The depth to bedrock ranges from minimized by using suitable methods of harvesting, laying 12 to 20 inches. In some areas the surface layer is stony. out skid trails in advance, and harvesting timber when the Included in this unit are small areas of McNull soils, soils are least susceptible to compaction. Ripping skid trails Carney and Medco soils on concave slopes, Rock outcrop and landings when the soils are dry can improve the growth on ridges and convex slopes, poorly drained soils near of plants. drainageways and on concave slopes, and soils that are Properly designed road drainage systems that include similar to the McMullin soil but have more than 35 percent carefully located culverts help to control erosion. Seeding, rock fragments or are less than 12 inches or more than 20 mulching, and benching areas that have been cut and filled inches deep over bedrock. Also included are McMullin soils also help to control erosion. Steep yarding paths, skid trails, that have slopes of more than 35 percent. Included areas and firebreaks are subject to rilling and gullying unless they make up about 20 percent of the total acreage. are protected by a plant cover or adequate water bars, or Permeability is moderate in the McMullin soil. Available both. water capacity is about 2 inches. The effective rooting depth The Manita soil may be subject to slumping; therefore, is 12 to 20 inches. Runoff is slow or medium, and the hazard road failure and landslides are likely to occur after road of water erosion is slight or moderate. construction and clearcutting. Slumping can be minimized This unit is used for livestock grazing and wildlife habitat by constructing logging roads in the less sloping areas, on The main limitations affecting livestock grazing are better suited soils if practical, and by installing properly compaction, erosion, droughtiness, and the depth to designed road drainage systems. Skid trails and unsurfaced bedrock. The vegetation suitable for grazing includes roads may be impassable during rainy periods. Logging bluebunch wheatgrass, Lemmon needlegrass, and pine roads require suitable surfacing for year-round use. bluegrass. If the range is overgrazed, the proportion of A high temperature in the surface layer and an insufficient preferred forage plants decreases and the proportion of less moisture supply in summer result in a high seedling mortality preferred forage plants increases. Grazing should be rate, especially on south- and southwest-facing slopes. To delayed until the more desirable forage plants have compensate for the expected high mortality rate, the larger achieved enough growth to withstand grazing pressure and seedlings or a greater number of seedlings should be the soil is firm enough to withstand trampling by livestock. planted. When the timber is harvested, leaving some of the Suitable management practices on this unit include larger trees unharvested provides shade for seedlings. The proper grazing use, deferred grazing, rotation grazing, seedling mortality rate also can be reduced on south- and and brush control. Areas that support a large amount of rooting depth is 12 to 20 inches. Runoff is rapid, and the competing vegetation can be improved by chemical or hazard of water erosion is high. mechanical treatment. In places the use of ground The McNull soil is moderately deep and well drained. It equipment is limited by the included areas of stony soils and formed in colluvium derived dominantly from andesite, tuff, Rock outcrop. and breccia. Typically, the surface is covered with a layer of This unit is poorly suited to range seeding. The main needles, leaves, and twigs about 1 inch thick. The surface limitations are the depth to bedrock, droughtiness, and the layer is dark reddish brown gravelly loam about 6 inches included areas of stony soils and Rock outcrop. The plants thick. The upper 6 inches of the subsoil is dark reddish selected for seeding should be those that meet the brown clay loam. The lower 20 inches is dark reddish brown seasonal requirements of livestock or wildlife, or both. cobbly clay. Weathered bedrock is at a depth of about 32 This unit is limited as a site for livestock watering inches. The depth to bedrock ranges from 20 to 40 inches. ponds and other water impoundments because of the In some areas the surface layer is stony or cobbly. slope and the depth to bedrock. Permeability is slow in the McNull soil. Available water The vegetative site is Loamy Shrub Scabland, 18- to capacity is about 4 inches. The effective rooting depth is 35-inch precipitation zone. 20 to 40 inches. Runoff is rapid, and the hazard of water erosion is high. 111G-McMullin-McNull gravelly loams, 35 to 60 This unit is used mainly for livestock grazing or wildlife percent south slopes. This map unit is on hillslopes. habitat. The McNull soil also is used for timber production. Elevation is 1,500 to 4,000 feet. The mean annual The main limitations affecting livestock grazing are the precipitation is 20 to 40 inches, the mean annual slope, erosion, and compaction. The McMullin soil also is temperature is 45 to 52 degrees F, and the average limited by the depth to bedrock. The vegetation suitable for frost-free period is 100 to 160 days. The native vegetation grazing includes Idaho fescue, bluebunch wheatgrass, and on the McMullin soil is mainly grasses, shrubs, and forbs. pine bluegrass on the McMullin soil and Idaho fescue, That on the McNull soil is mainly conifers and hardwoods western fescue, and tall trisetum on the McNull soil. If the and an understory of grasses, shrubs, and forbs. range is overgrazed, the proportion of preferred forage This unit is about 60 percent McMullin soil and 25 plants decreases and the proportion of less preferred percent McNull soil. The components of this unit occur as forage plants increases. Grazing should be delayed until areas so intricately intermingled that mapping them the more desirable forage plants have achieved enough separately was not practical at the scale used. growth to withstand grazing pressure and the soils are firm Included in this unit are small areas of Medco soils on enough to withstand trampling by livestock. concave slopes, Rock outcrop on ridges and convex Suitable management practices on this unit include slopes, poorly drained soils near drainageways and on proper grazing use, deferred grazing, rotation grazing, and concave slopes, soils that are similar to the McNull soil but brush control. Mechanical treatment is not practical have bedrock at a depth of more than 40 inches, soils that because of the slope and the included areas of Rock are similar to the McMullin soil but have bedrock at a depth outcrop and stony soils. of less than 12 or more than 20 inches, and soils that are This unit is poorly suited to range seeding. The main similar to the McNull and McMullin soils but have more than limitations are the slope of both soils and the depth to 35 percent rock fragments. Also included are small areas of bedrock in the McMullin soil. McNull and McMullin soils that have slopes of less than 35 The slope limits access by livestock. As a result, the or more than 60 percent. Included areas make up about 15 less sloping areas tend to be overgrazed. Constructing percent of the total acreage. trails or walkways allows livestock to graze in areas where The McMullin soil is shallow and well drained. It formed access is limited. in colluvium derived dominantly from andesite, tuff, and This unit is limited as a site for livestock watering breccia. Typically, the surface layer is dark reddish brown ponds and other water impoundments because of the gravelly loam about 7 inches thick. The subsoil is dark slope and the depth to bedrock. reddish brown gravelly clay loam about 10 inches thick. Thinning, logging, and fire on the McNull soil reduce the Bedrock is at a depth of about 17 inches. The depth to density of the overstory canopy and increase the bedrock ranges from 12 to 20 inches. In some areas the production of understory vegetation. Areas that support a surface layer is stony. large amount of competing vegetation can be improved by Permeability is moderate in the McMullin soil. Available prescribed burning or by chemical or mechanical treatment. water capacity is about 2 inches. The effective The McNull soil is suited to the production of Douglas fir high mortality rate, the larger seedlings or a greater number and ponderosa pine. Other species that grow on this unit of seedlings should be planted. When the timber is include incense cedar, California black oak, and Pacific harvested, leaving some of the larger trees unharvested madrone. The understory vegetation includes Pacific provides shade for seedlings. The seedling mortality rate serviceberry, tall Oregongrape, and California fescue. also can be reduced by providing artificial shade for On the basis of a 100 year site curve, the mean site seedlings. Reforestation can be accomplished by planting index for Douglas fir is 95 on the McNull soil. The yield at ponderosa pine and Douglas fir seedlings. culmination of the mean annual increment is 4,620 cubic Undesirable plants limit natural or artificial feet per acre in a fully stocked, even-aged stand of trees at reforestation unless intensive site preparation and 60 years and 37,120 board feet per acre (Scribner rule) at maintenance measures are applied. Mulching around 160 years. On the basis of a 50-year curve, the mean site seedlings helps to maintain the moisture supply in index is 70. summer and minimizes competition from undesirable The main limitations affecting timber production on the understory plants. McNull soil are the slope, erosion, compaction, seedling The vegetative site in areas of the McMullin soil is mortality, and plant competition. Also, the bedrock Shallow Mountain Slopes, 22- to 30-inch precipitation restricts root growth. As a result, windthrow is a hazard. zone, and the one in areas of the McNull soil is Pine- Wheeled and tracked logging equipment can be used in Douglas Fir-Fescue. the less sloping areas, but cable yarding generally is safer and results in less surface disturbance. Using standard 112F-McMullin-Medco complex, 12 to 50 percent wheeled and tracked equipment when the soil is moist slopes. This map unit is on hillslopes (fig. 9). Elevation is causes rutting and compaction. Puddling can occur when 1,300 to 4,000 feet. The mean annual precipitation is 20 to the soil is wet. Using low-pressure ground equipment 35 inches, the mean annual temperature is 45 to 52 causes less damage to the soil and helps to maintain degrees F, and the average frost-free period is 100 to 160 productivity. Compaction can be minimized by using days. The native vegetation on the McMullin soil is mainly suitable methods of harvesting, laying out skid trails in grasses, shrubs, and forbs. That on the Medco soil is advance, and harvesting timber when the soil is least mainly hardwoods and an understory of grasses, shrubs, susceptible to compaction. Ripping skid trails and landings and forbs. when the soil is dry can improve the growth of plants. This unit is about 50 percent McMullin soil and 30 Properly designed road drainage systems that include percent Medco soil. The components of this unit occur as carefully located culverts help to control erosion. Seeding, areas so intricately intermingled that mapping them mulching, and benching areas that have been cut and filled separately was not practical at the scale used. also help to control erosion. Steep yarding paths, skid trails, Included in this unit are small areas of Carney and and firebreaks are subject to rilling and gullying unless they McNull soils, Rock outcrop on ridges and convex slopes, are protected by a plant cover or adequate water bars, or and soils that are similar to the McMullin soil but have more both. Cutbanks occasionally slump when the soil is than 35 percent rock fragments or have bedrock at a depth saturated. of less than 12 or more than 20 inches. Also included are Constructing logging roads on the steeper slopes can small areas of soils that are similar to the Medco soil but result in a high risk of erosion. Building the roads at have bedrock at a depth of more than 40 inches, poorly midslope requires extensive cutting and filling and removes drained soils near drainageways and on concave slopes, land from production. Material that is discarded when the and Medco and McMullin soils that have slopes of less than roads are built can damage vegetation and is a potential 12 or more than 50 percent. Included areas make up about source of sedimentation. If the material becomes saturated, 20 percent of the total acreage. avalanches of debris can occur. End hauling of the waste The McMullin soil is shallow and well drained. It formed material minimizes damage to the vegetation downslope in colluvium derived dominantly from andesite, tuff, and and reduces the risk of sedimentation. Skid trails and breccia. Typically, the surface layer is dark reddish brown unsurfaced roads may be impassable during rainy periods. gravelly loam about 7 inches thick. The subsoil is dark Logging roads require suitable surfacing for year-round use. reddish brown gravelly clay loam about 10 inches thick. A high temperature in the surface layer and an Bedrock is at a depth of about 17 inches. The depth to insufficient moisture supply in summer increase the bedrock ranges from 12 to 20 inches. In some areas the seedling mortality rate. To compensate for the expected surface layer is stony. Permeability is moderate in the McMullin soil. Available water capacity is about 2 inches. The effective Figure 9.-An area of McMullin-Medco complex, 12 to 50 percent slopes. The shallow McMullin soil is in the foreground, and the moderately deep Medco soil is in the background. rooting depth is 12 to 20 inches. Runoff is medium, and the This unit is limited as a site for livestock watering hazard of water erosion is moderate. ponds and other water impoundments because of the The Medco soil is moderately deep and moderately well slope and the depth to bedrock. drained. It formed in colluvium derived dominantly from The vegetative site in areas of the McMullin soil is andesite, tuff, and breccia. Typically, the surface layer is Loamy Shrub Scabland, 18- to 35-inch precipitation zone, very dark brown and very dark grayish brown cobbly clay and the one in areas of the Medco soil is Loamy Hills, 20- loam about 7 inches thick. The next layer is very dark to 35-inch precipitation zone. grayish brown cobbly clay loam about 5 inches thick. The subsoil is brown clay about 18 inches thick. Weathered 113E-McMullin-Rock outcrop complex, 3 to 35 bedrock is at a depth of about 30 inches. The depth to percent slopes. This map unit is on hillslopes. bedrock ranges from 20 to 40 inches. In some areas the Elevation is 1,000 to 4,000 feet. The mean annual surface layer is stony. precipitation is 18 to 40 inches, the mean annual Permeability is very slow in the Medco soil. Available temperature is 45 to 52 degrees F, and the average water capacity is about 4 inches. The effective rooting depth frost-free period is 100 to 180 days. The native is limited by a dense layer of clay at a depth of 6 to 18 vegetation is mainly grasses, shrubs, and forbs. inches. Runoff is medium, and the hazard of water erosion is This unit is about 60 percent McMullin soil and 25 moderate. The water table, which is perched above the layer percent Rock outcrop. The components of this unit occur of clay, is at a depth of 0.5 foot to 1.5 feet from December as areas so intricately intermingled that mapping them through March. separately was not practical at the scale used. This unit is used for livestock grazing and wildlife Included in this unit are small areas of Lorella and habitat. The main limitations affecting livestock grazing on Skookum soils, McNull soils on north-facing slopes, Carney the McMullin soil are erosion, compaction, the depth to and Medco soils on concave slopes, poorly drained soils bedrock, droughtiness, and the slope. The main limitations near drainageways and on concave slopes, and soils that in areas of the Medco soil are erosion, compaction, cobbles are similar to the McMullin soil but have more than 35 and stones on the surface, wetness in winter and spring, percent rock fragments or are less than 12 inches or more droughtiness in summer and fall, and the slope. The than 20 inches deep over bedrock. Also included are small vegetation suitable for grazing includes Idaho fescue, areas of McMullin soils that have slopes of more than 35 bluebunch wheatgrass, and pine bluegrass. If the range is percent. Included areas make up about 15 percent of the overgrazed, the proportion of preferred forage plants total acreage. decreases and the proportion of less preferred forage The McMullin soil is shallow and well drained. It formed plants increases. in colluvium derived dominantly from igneous and Because the Medco soil remains wet for long periods in metamorphic rock. Typically, the surface layer is dark spring, grazing should be delayed until the more desirable reddish brown gravelly loam about 7 inches thick. The forage plants have achieved enough growth to withstand subsoil is dark reddish brown gravelly clay loam about 10 grazing pressure and the soil is firm enough to withstand inches thick. Bedrock is at a depth of about 17 inches. The trampling by livestock. Compaction can be minimized by depth to bedrock ranges from 12 to 20 inches. grazing first in the areas that dry out earliest. Permeability is moderate in the McMullin soil. Available Suitable management practices on this unit include water capacity is about 2 inches. The effective rooting depth proper grazing use, deferred grazing, rotation grazing, and is 12 to 20 inches. Runoff is slow or medium, and the brush control. Areas that support a large amount of hazard of water erosion is slight or moderate. competing vegetation can be improved by prescribed Rock outcrop consists of areas of exposed bedrock. burning or by chemical or mechanical treatment. In places Runoff is very rapid in these areas. the use of ground equipment is limited by the wetness, the This unit is used for livestock grazing and wildlife slope, and the included areas of stony soils and Rock habitat. The main limitations affecting livestock grazing are outcrop. compaction, erosion, the Rock outcrop, stones on the Range seeding is suitable on the Medco soil if the site is surface, droughtiness, and the depth to bedrock. The in poor condition. The main limitations are wetness in winter vegetation suitable for grazing includes bluebunch and spring and droughtiness in summer and fall. The plants wheatgrass, Lemmon needlegrass, and pine bluegrass. If selected for seeding should be those that meet the the range is overgrazed, the proportion of preferred forage seasonal requirements of livestock or wildlife, or both. The plants decreases and the proportion of less preferred suitability of the McMullin soil for seeding is poor. The main forage plants increases. Grazing should be delayed until limitations are the depth to bedrock and droughtiness. the more desirable forage plants have achieved enough growth to withstand grazing pressure rooting depth is 12 to 20 inches. Runoff is rapid, and and the soil is firm enough to withstand trampling by the hazard of water erosion is high. livestock. Rock outcrop consists of areas of exposed bedrock. Suitable management practices on this unit include Runoff is very rapid in these areas. proper grazing use, deferred grazing, rotation grazing, and This unit is used for livestock grazing and wildlife brush control. Areas that support a large amount of habitat. The main limitations affecting livestock grazing competing vegetation can be improved by chemical or are the slope, erosion, compaction, the Rock outcrop, mechanical treatment. The use of ground equipment is not stones on the surface, droughtiness, and the depth to practical because of the stones on the surface and the bedrock. The vegetation suitable for grazing includes included areas of Rock outcrop. Idaho fescue, bluebunch wheatgrass, and pine This unit is poorly suited to range seeding. The main bluegrass. If the range is overgrazed, the proportion of limitations are the depth to bedrock, droughtiness, the preferred forage plants decreases and the proportion of stones on the surface, and the Rock outcrop. The plants less preferred forage plants increases. Grazing should selected for seeding should be those that meet the be delayed until the more desirable forage plants have seasonal requirements of livestock or wildlife, or both. achieved enough growth to withstand grazing pressure and the soil is firm enough to withstand trampling by This unit is limited as a site for livestock watering livestock. ponds and other water impoundments because of the Suitable management practices on this unit include slope and the depth to bedrock. proper grazing use, deferred grazing, rotation grazing, The vegetative site is Loamy Shrub Scabland, 18- to and brush control. Areas that support a large amount of 35-inch precipitat ion zone. competing vegetation can be improved by chemical or mechanical treatment. The use of ground equipment is 113G-McMullin-Rock outcrop complex, 35 to 60 not practical because of the stones on the surface, the percent slopes. This map unit is on hillslopes. Elevation Rock outcrop, and the slope. is 1,000 to 4,000 feet. The mean annual precipitation is This unit is poorly suited to range seeding. The main 18 to 40 inches, the mean annual temperature is 45 to 52 limitations are the slope, the depth to bedrock, degrees F, and the average frost-free period is 100 to droughtiness, the stones on the surface, and the Rock 180 days. The native vegetation is mainly grasses, outcrop. The plants selected for seeding should be shrubs, and forbs. those that meet the seasonal requirements of livestock This unit is about 60 percent McMullin soil and 30 or wildlife, or both. percent Rock outcrop, The components of this unit The slope and the Rock outcrop limit access by occur as areas so intricately intermingled that mapping livestock. As a result, the less sloping areas tend to be them separately was not practical at the scale used. overgrazed. Constructing trails or walkways allows Included in this unit are small areas of Lorella and livestock to graze in areas where access is limited. Skookum soils, McNull soils on north-facing slopes, This unit is limited as a site for livestock watering Carney and Medco soils on concave slopes, and poorly ponds and other water impoundments because of the drained soils near drainageways and on concave slope and the depth to bedrock. slopes. Also included are small areas of soils that are The vegetative site is Shallow Mountain Slopes, 22to similar to the McMullin soil but have more than 35 30-inch precipitation zone. percent rock fragments or are less than 12 inches or 114E-McNull loam, 12 to 35 percent north slopes. more than 20 inches deep over bedrock and McMullin This moderately deep, well drained soil is on hillslopes. It soils that have slopes of less than 35 or more than 60 formed in colluvium derived dominantly from andesite, tuff, percent. Included areas make up about 10 percent of and breccia. Elevation is 1,500 to 4,000 feet. The mean the total acreage. annual precipitation is 25 to 40 inches, the mean annual The McMullin soil is shallow and well drained. It temperature is 45 to 52 degrees F, and the average formed in colluvium derived dominantly from igneous frost-free period is 100 to 160 days. The native vegetation is and metamorphic rock. Typically, the surface layer is mainly conifers and hardwoods and an understory of dark reddish brown gravelly loam about 7 inches thick. grasses, shrubs, and (orbs. The subsoil is dark reddish brown gravelly clay loam Typically, the surface is covered with a layer of needles, about 10 inches thick. Bedrock is at a depth of about 17 leaves, and twigs about 1 inch thick. The surface layer is inches. The depth to bedrock ranges from 12 to 20 dark reddish brown loam about 6 inches thick. The upper 6 inches. inches of the subsoil is dark reddish brown clay loam. The Permeability is moderate in the McMullin soil. lower 20 inches is dark reddish Available water capacity is about 2 inches. The effective brown cobbly clay. Weathered bedrock is at a depth of paths, skid trails, and firebreaks are subject to rilling and about 32 inches. The depth to bedrock ranges from 20 to gullying unless they are protected by a plant cover or 40 inches. In some areas the surface layer is stony or adequate water bars, or both. Skid trails and unsurfaced cobbly. roads may be impassable during rainy periods. Logging Included in this unit are small areas of McMullin soils and roads require suitable surfacing for year-round use. Rock outcrop on ridges and convex slopes, Medco soils on Undesirable plants limit natural or artificial reforestation concave slopes, poorly drained soils near drainageways and unless intensive site preparation and maintenance on concave slopes, and soils that are similar to the McNull measures are applied. Reforestation can be accomplished soil but have bedrock at a depth of more than 40 inches or by planting Douglas fir and ponderosa pine seedlings. have more than 35 percent rock fragments. Also included Mulching around seedlings helps to maintain the moisture are small areas of McNull soils that have slopes of less than supply in summer and minimizes competition from 12 or more than 35 percent. Included areas make up about undesirable understory plants. 20 percent of the total acreage. The main limitations affecting livestock grazing are Permeability is slow in the McNull soil. Available water compaction and erosion. The native vegetation suitable for capacity is about 4 inches. The effective rooting depth is grazing includes western fescue, mountain brome, and tall 20 to 40 inches. Runoff is medium, and the hazard of trisetum. If the understory is overgrazed, the proportion of water erosion is moderate. preferred forage plants decreases and the proportion of This unit is used for timber production, livestock less preferred forage plants increases. grazing, and wildlife habitat. A planned grazing system that includes timely deferment This unit is suited to the production of Douglas fir and of grazing, rotation grazing, and proper livestock distribution ponderosa pine. Other species that grow on this unit helps to prevent overgrazing of the understory and damage include incense cedar, California black oak, and Pacific to the soil. Grazing should be delayed until the more madrone. The understory vegetation includes desirable forage plants have achieved enough growth to creambush oceanspray, common snowberry, and tall withstand grazing pressure and the soil is firm enough to Oregongrape. withstand trampling by livestock. On the basis of a 100-year site curve, the mean site Thinning, logging, and fire reduce the density of the index for Douglas fir is 105. The yield at culmination of the overstory canopy and increase the production of mean annual increment is 5,460 cubic feet per acre in a understory vegetation. Areas that support a large amount fully stocked, even-aged stand of trees at 60 years and of competing vegetation can be improved by prescribed 45,600 board feet per acre (Scribner rule) at 150 years. On burning or by chemical or mechanical treatment. Seeding the basis of a 50-year curve, the mean site index is 80. disturbed areas to suitable plants increases forage The main limitations affecting timber production are production and reduces the risk of erosion. erosion, compaction, and plant competition. Also, the The vegetative site is Douglas Fir Forest. bedrock restricts root growth. As a result, windthrow is a hazard. 114G-McNull loam, 35 to 60 percent north slopes. Wheeled and tracked logging equipment can be used in This moderately deep, well drained soil is on hillslopes. It the less sloping areas, but cable yarding generally is safer formed in colluvium derived dominantly from andesite, tuff, in the more sloping areas and results in less surface and breccia. Elevation is 1,500 to 4,000 feet. The mean disturbance. Using standard wheeled and tracked annual precipitation is 25 to 40 inches, the mean annual equipment when the soil is moist causes rutting and temperature is 45 to 52 degrees F, and the average compaction. Puddling can occur when the soil is wet. Using frost-free period is 100 to 160 days. The native vegetation is low-pressure ground equipment causes less damage to the mainly conifers and hardwoods and an understory of soil and helps to maintain productivity. Compaction can be grasses, shrubs, and forbs. minimized by using suitable methods of harvesting, laying Typically, the surface is covered with a layer of needles, out skid trails in advance, and harvesting timber when the leaves, and twigs about 1 inch thick. The surface layer is soil is least susceptible to compaction. Ripping skid trails dark reddish brown loam about 6 inches thick. The upper 6 and landings when the soil is dry can improve the growth of inches of the subsoil is dark reddish brown clay loam. The plants. lower 20 inches is dark reddish brown cobbly clay. Properly designed road drainage systems that include Weathered bedrock is at a depth of about 32 inches. The carefully located culverts help to control erosion. Seeding, depth to bedrock ranges from 20 mulching, and benching areas that have been cut and filled also help to control erosion. Steep yarding to 40 inches. In some areas the surface layer is stony or or adequate water bars, or both. Cutbanks occasionally cobbly. slump when the soil is saturated. Included in this unit are small areas of McMullin soils and Constructing logging roads on the steeper slopes can Rock outcrop on ridges and convex slopes, Medco soils on result in a high risk of erosion. Building the roads at concave slopes, poorly drained soils near drainageways and midslope requires extensive cutting and filling and removes on concave slopes, and soils that are similar to the McNull land from production. Material that is discarded when the soil but have bedrock at a depth of more than 40 inches or roads are built can damage vegetation and is a potential have more than 35 percent rock fragments. Also included source of sedimentation. If the material becomes saturated, are small areas of McNull soils that have slopes of less than avalanches of debris can occur. End hauling of the waste 35 or more than 60 percent. Included areas make up about material minimizes damage to the vegetation downslope 20 percent of the total acreage. and reduces the risk of sedimentation. Skid trails and Permeability is slow in the McNull soil. Available water unsurfaced roads may be impassable during rainy periods. capacity is about 4 inches. The effective rooting depth is Logging roads require suitable surfacing for year-round use. 20 to 40 inches. Runoff is rapid, and the hazard of water Undesirable plants limit natural or artificial reforestation erosion is high. unless intensive site preparation and maintenance This unit is used for timber production, livestock measures are applied. Reforestation can be accomplished grazing, and wildlife habitat. by planting Douglas fir and ponderosa pine seedlings. This unit is suited to the production of Douglas fir and Mulching around seedlings helps to maintain the moisture ponderosa pine. Other species that grow on this unit supply in summer and minimizes competition from include incense cedar, California black oak, and Pacific undesirable understory plants. madrone. The understory vegetation includes The main limitations affecting livestock grazing are creambush oceanspray, common snowberry, and tall erosion, compaction, and the slope. The native vegetation Oregongrape. suitable for grazing includes western fescue, mountain On the basis of a 100-year site curve, the mean site brome, and tall trisetum. If the understory is overgrazed, index for Douglas fir is 105. The yield at culmination of the the proportion of preferred forage plants decreases and the mean annual increment is 5,460 cubic feet per acre in a proportion of less preferred forage plants increases. fully stocked, even-aged stand of trees at 60 years and A planned grazing system that includes timely deferment 45,600 board feet per acre (Scribner rule) at 150 years. On of grazing, rotation grazing, and proper livestock distribution the basis of a 50-year curve, the mean site index is 80. helps to prevent overgrazing of the understory and damage The main limitations affecting timber production are the to the soil. Grazing should be delayed until the more slope, erosion, compaction, and plant competition. Also, desirable forage plants have achieved enough growth to the bedrock restricts root growth. As a result, windthrow is withstand grazing pressure and the soil is firm enough to a hazard. withstand trampling by livestock. Wheeled and tracked logging equipment can be used in Thinning, logging, and fire reduce the density of the the less sloping areas, but cable yarding generally is safer overstory canopy and increase the production of and results in less surface disturbance. Using standard understory vegetation. Areas that support a large amount wheeled and tracked equipment when the soil is moist of competing vegetation can be improved by prescribed causes rutting and compaction. Puddling can occur when burning or by chemical or mechanical treatment. Seeding the soil is wet. Using low-pressure ground equipment disturbed areas to suitable plants increases forage causes less damage to the soil and helps to maintain production and reduces the risk of erosion. productivity. Compaction can be minimized by using The vegetative site is Douglas Fir Forest. suitable methods of harvesting, laying out skid trails in advance, and harvesting timber when the soil is wet and 115E-McNull gravelly loam, 12 to 35 percent south susceptible to compaction. Ripping skid trails and landings slopes. This moderately deep, well drained soil is on when the soil is dry can improve the growth of plants. hillslopes. It formed in colluvium derived dominantly from Properly designed road drainage systems that include andesite, tuff, and breccia. Elevation is 1,500 to 4,000 feet. carefully located culverts help to control erosion. Seeding, The mean annual precipitation is 25 to 40 inches, the mean mulching, and benching areas that have been cut and filled annual temperature is 45 to 52 degrees F, and the average also help to control erosion. Steep yarding paths, skid trails, frost-free period is 100 to and firebreaks are subject to rilling and gullying unless they are protected by a plant cover 160 days. The native vegetation is mainly conifers and Compaction can be minimized by using suitable methods of hardwoods and an understory of grasses, shrubs, and harvesting, laying out skid trails in advance, and harvesting forbs. timber when the soil is least susceptible to compaction. Typically, the surface is covered with a layer of needles, Ripping skid trails and landings when the soil is dry can leaves, and twigs about 1 inch thick. The surface layer is improve the growth of plants. dark reddish brown gravelly loam about 6 inches thick. The Properly designed road drainage systems that include upper 6 inches of the subsoil is dark reddish brown clay carefully located culverts help to control erosion. Seeding, loam. The lower 20 inches is dark reddish brown cobbly mulching, and benching areas that have been cut and filled clay. Weathered bedrock is at a depth of about 32 inches. also help to control erosion. Steep yarding paths, skid trails, The depth to bedrock ranges from 20 to 40 inches. In some and firebreaks are subject to rilling and gullying unless they areas the surface layer is stony or cobbly. are protected by a plant cover or adequate water bars, or Included in this unit are small areas of McMullin soils and both. Skid trails and unsurfaced roads may be impassable Rock outcrop on ridges and convex slopes, Medco soils on during rainy periods. Logging roads require suitable concave slopes, poorly drained soils near drainageways and surfacing for year-round use. on concave slopes, and soils that are similar to the McNull A high temperature in the surface layer and an soil but have bedrock at a depth of more than 40 inches or insufficient moisture supply in summer increase the have more than 35 percent rock fragments. Also included seedling mortality rate. To compensate for the expected are small areas of McNull soils that have slopes of less than high mortality rate, the larger seedlings or a greater number 12 or more than 35 percent. Included areas make up about of seedlings should be planted. When the timber is 20 percent of the total acreage. harvested, leaving some of the larger trees unharvested Permeability is slow in the McNull soil. Available water provides shade for seedlings. Reforestation can be capacity is about 4 inches. The effective rooting depth is accomplished by planting Douglas fir and ponderosa pine 20 to 40 inches. Runoff is medium, and the hazard of seedlings. water erosion is moderate. Undesirable plants limit natural or artificial This unit is used for timber production, livestock reforestation unless intensive site preparation and grazing, and wildlife habitat. maintenance measures are applied. Mulching around This unit is suited to the production of Douglas fir and seedlings helps to maintain the moisture supply in ponderosa pine. Other species that grow on this unit summer and minimizes competition from undesirable include incense cedar, California black oak, and Pacific understory plants. madrone. The understory vegetation includes Pacific The main limitations affecting livestock grazing are serviceberry, tall Oregongrape, and California fescue. compaction and erosion. The native vegetation suitable for On the basis of a 100-year site curve, the mean site grazing includes Idaho fescue, tall trisetum, and western index for Douglas fir is 95. The yield at culmination of the fescue. If the understory is overgrazed, the proportion of mean annual increment is 4,620 cubic feet per acre in a preferred forage plants decreases and the proportion of fully stocked, even-aged stand of trees at 60 years and less preferred forage plants increases. 37,120 board feet per acre (Scribner rule) at 160 years. On A planned grazing system that includes timely deferment the basis of a 50-year curve, the mean site index is 70. of grazing, rotation grazing, and proper livestock distribution The main limitations affecting timber production are helps to prevent overgrazing of the understory and damage erosion, compaction, seedling mortality, and plant to the soil. Grazing should be delayed until the more competition. Also, the bedrock restricts root growth. As a desirable forage plants have achieved enough growth to result, windthrow is a hazard. withstand grazing pressure and the soil is firm enough to Wheeled and tracked logging equipment can be used in withstand trampling by livestock. the less sloping areas, but cable yarding generally is safer Thinning, logging, and fire reduce the density of the in the more sloping areas and results in less surface overstory canopy and increase the production of disturbance. Using standard wheeled and tracked understory vegetation. Areas that support a large amount equipment when the soil is moist causes rutting and of competing vegetation can be improved by prescribed compaction. Puddling can occur when the soil is wet. Using burning or by chemical or mechanical treatment. Seeding low-pressure ground equipment causes less damage to the disturbed areas to suitable plants increases forage soil and helps to maintain productivity. production and reduces the risk of erosion. The vegetative site is Pine-Douglas Fir-Fescue. 115G--McNull gravelly loam, 35 to 60 percent south safer and results in less surface disturbance. Using slopes. This moderately deep, well drained soil is on standard wheeled and tracked equipment when the soil is hillslopes. It formed in colluvium derived dominantly from moist causes rutting and compaction. Puddling can occur andesite, tuff, and breccia. Elevation is 1,500 to 4,000 feet. when the soil is wet. Using low-pressure ground equipment The mean annual precipitation is 25 to 40 inches, the mean causes less damage to the soil and helps to maintain annual temperature is 45 to 52 degrees F, and the average productivity. Compaction can be minimized by using frost-free period is 100 to 160 days. The native vegetation is suitable methods of harvesting, laying out skid trails in mainly conifers and hardwoods and an understory of advance, and harvesting timber when the soil is least grasses, shrubs, and forbs. susceptible to compaction. Ripping skid trails and landings Typically, the surface is covered with a layer of needles, when the soil is dry can improve the growth of plants. leaves, and twigs about 1 inch thick. The surface layer is Properly designed road drainage systems that include dark reddish brown gravelly loam about 6 inches thick. The carefully located culverts help to control erosion. Seeding, upper 6 inches of the subsoil is dark reddish brown clay mulching, and benching areas that have been cut and filled loam. The lower 20 inches is dark reddish brown cobbly also help to control erosion. Steep yarding paths, skid trails, clay. Weathered bedrock is at a depth of about 32 inches. and firebreaks are subject to rilling and gullying unless they The depth to bedrock ranges from 20 to 40 inches. In some are protected by a plant cover or adequate water bars, or areas the surface layer is stony or cobbly. both. Cutbanks occasionally slump when the soil is Included in this unit are small areas of McMullin soils and saturated. Rock outcrop on ridges and convex slopes, Medco soils on Constructing logging roads on the steeper slopes can concave slopes, poorly drained soils near drainageways and result in a high risk of erosion. Building the roads at on concave slopes, and soils that are similar to the McNull midslope requires extensive cutting and filling and removes soil but have bedrock at a depth of more than 40 inches or land from production. Material that is discarded when the have more than 35 percent rock fragments. Also included roads are built can damage vegetation and is a potential are small areas of McNull soils that have slopes of less than source of sedimentation. If the material becomes saturated, 35 or more than 60 percent. Included areas make up about avalanches of debris can occur. End hauling of the waste 20 percent of the total acreage. material minimizes damage to the vegetation downslope Permeability is slow in the McNull soil. Available water and reduces the risk of sedimentation. Skid trails and capacity is about 4 inches. The effective rooting depth is unsurfaced roads may be impassable during rainy periods. 20 to 40 inches. Runoff is rapid, and the hazard of water Logging roads require suitable surfacing for year-round use. erosion is high. A high temperature in the surface layer and an This unit is used for timber production, livestock insufficient moisture supply in summer increase the seedling grazing, and wildlife habitat. mortality rate. To compensate for the expected high This unit is suited to the production of Douglas fir and mortality rate, the larger seedlings or a greater number of ponderosa pine. Other species that grow on this unit seedlings should be planted. When the timber is harvested, include incense cedar, California black oak, and Pacific leaving some of the larger trees unharvested provides madrone. The understory vegetation includes Pacific shade for seedlings. The seedling mortality rate also can be serviceberry, tall Oregongrape, and California fescue. reduced by providing artificial shade for seedlings. On the basis of a 100-year site curve, the mean site Reforestation can be accomplished by planting Douglas fir index for Douglas fir is 95. The yield at culmination of the and ponderosa pine seedlings. mean annual increment is 4,620 cubic feet per acre in a Undesirable plants limit natural or artificial fully stocked, even-aged stand of trees at 60 years and reforestation unless intensive site preparation and 37,120 board feet per acre (Scribner rule) at 160 years. On maintenance measures are applied. Mulching around the basis of a 50-year curve, the mean site index is 70. seedlings helps to maintain the moisture supply in The main limitations affecting timber production are the summer and minimizes competition from undesirable slope, erosion, compaction, seedling mortality, and plant understory plants. competition. Also, the bedrock restricts root growth. As a The main limitations affecting livestock grazing are result, windthrow is a hazard. erosion, compaction, and the slope. The native Wheeled and tracked logging equipment can be used in vegetation suitable for grazing includes Idaho fescue, tall the less sloping areas, but cable yarding generally is trisetum, and western fescue. If the understory is overgrazed, the proportion of preferred forage plants decreases and the proportion of less preferred forage plants increases. A planned grazing system that includes timely deferment ranges from 20 to 40 inches. In some areas the surface of grazing, rotation grazing, and proper livestock distribution layer is stony or cobbly. helps to prevent overgrazing of the understory and damage Permeability is slow in the McNull soil. Available water to the soil. Grazing should be delayed until the more capacity is about 4 inches. The effective rooting depth is desirable forage plants have achieved enough growth to 20 to 40 inches. Runoff is medium, and the hazard of withstand grazing pressure and the soil is firm enough to water erosion is moderate. withstand trampling by livestock. The McMullin soil is shallow and well drained. It formed Thinning, logging, and fire reduce the density of the in colluvium derived dominantly from andesite, tuff, and overstory canopy and increase the production of breccia. Typically, the surface layer is dark reddish brown understory vegetation. Areas that support a large amount gravelly loam about 7 inches thick. The subsoil is dark of competing vegetation can be improved by prescribed reddish brown gravelly clay loam about 10 inches thick. burning or by chemical or mechanical treatment. Seeding Bedrock is at a depth of about 17 inches. The depth to disturbed areas to suitable plants increases forage bedrock ranges from 12 to 20 inches. In some areas the production and reduces the risk of erosion. surface layer is stony. The vegetative site is Pine-Douglas Fir-Fescue. Permeability is moderate in the McMullin soil. Available water capacity is about 2 inches. The effective rooting depth 116E-McNull-McMullin gravelly loams, 12 to 35 is 12 to 20 inches. Runoff is medium, and the hazard of percent south slopes. This map unit is on hillslopes. water erosion is moderate. Elevation is 1,500 to 4,000 feet. The mean annual This unit is used for timber production, livestock precipitation is 20 to 40 inches, the mean annual grazing, and wildlife habitat. temperature is 45 to 52 degrees F, and the average The McNull soil is suited to the production of Douglas fir frost-free period is 100 to 160 days. The native vegetation and ponderosa pine. Other species that grow on this unit on the McNull soil is mainly conifers and hardwoods and include incense cedar, California black oak, and Pacific an understory of grasses, shrubs, and forbs. That on the madrone. The understory vegetation includes Pacific McMullin soil is mainly grasses, shrubs, and forbs. serviceberry, tall Oregongrape, and California fescue. This unit is about 55 percent McNull soil and 30 percent On the basis of a 100-year site curve, the mean site McMullin soil. The components of this unit occur as areas index for Douglas fir is 95 on the McNull soil. The yield at so intricately intermingled that mapping them separately culmination of the mean annual increment is 4,620 cubic was not practical at the scale used. feet per acre in a fully stocked, even-aged stand of trees at Included in this unit are small areas of Medco soils on 60 years and 37,120 board feet per acre (Scribner rule) at concave slopes, Rock outcrop on ridges and convex 160 years. On the basis of a 50-year curve, the mean site slopes, poorly drained soils near drainageways and on index is 70. concave slopes, and soils that are similar to the McNull soil The main limitations affecting timber production on the but have bedrock at a depth of more than 40 inches. Also McNull soil are erosion, compaction, seedling mortality, and included are small areas of soils that are similar to the plant competition. Also, the bedrock restricts root growth. McMullin soil but have bedrock at a depth of less than 12 or As a result, windthrow is a hazard. more than 20 inches, soils that are similar to the McNull Wheeled and tracked logging equipment can be used in and McMullin soils but have more than 35 percent rock the less sloping areas, but cable yarding generally is safer fragments, and McNull and McMullin soils that have slopes in the more sloping areas and results in less surface of less than 12 or more than 35 percent. Included areas disturbance. Using standard wheeled and tracked make up about 15 percent of the total acreage. equipment when the soil is moist causes rutting and The McNull soil is moderately deep and well drained. It compaction. Puddling can occur when the soil is wet. Using formed in colluvium derived dominantly from andesite, tuff, low-pressure ground equipment causes less damage to the and breccia. Typically, the surface is covered with a layer of soil and helps to maintain productivity. Compaction can be needles, leaves, and twigs about 1 inch thick. The surface minimized by using suitable methods of harvesting, laying layer is dark reddish brown gravelly loam about 6 inches out skid trails in advance, and harvesting timber when the thick. The upper 6 inches of the subsoil is dark reddish soil is least susceptible to compaction. Ripping skid trails brown clay loam. The lower 20 inches is dark reddish brown and landings when the soil is dry can improve the growth of cobbly clay. Weathered bedrock is at a depth of about 32 plants. inches. The depth to bedrock Properly designed road drainage systems that include carefully located culverts help to control erosion. Seeding, mulching, and benching areas that have been cut and filled also help to control erosion. Steep yarding paths, skid trails, and firebreaks are subject to rilling and McMullin soil is Loamy Shrub Scabland, 18- to 35-inch gullying unless they are protected by a plant cover or precipitation zone. adequate water bars, or both. Skid trails and unsurfaced roads may be impassable during rainy periods. Logging 116G-McNull-McMullin gravelly loams, 35 to 60 roads require suitable surfacing for year-round use. percent south slopes. This map unit is on hillslopes. A high temperature in the surface layer and an Elevation is 1,500 to 4,000 feet. The mean annual insufficient moisture supply in summer increase the precipitation is 20 to 40 inches, the mean annual seedling mortality rate. To compensate for the expected temperature is 45 to 52 degrees F, and the average high mortality rate, the larger seedlings or a greater number frost-free period is 100 to 160 days. The native vegetation of seedlings should be planted. When the timber is on the McNull soil is mainly conifers and hardwoods and harvested, leaving some of the larger trees unharvested an understory of grasses, shrubs, and forbs. That on the provides shade for seedlings. Reforestation can be McMullin soil is mainly grasses, shrubs, and forbs. accomplished by planting Douglas fir and ponderosa pine This unit is about 55 percent McNull soil and 30 percent seedlings. McMullin soil. The components of this unit occur as areas Undesirable plants limit natural or artificial so intricately intermingled that mapping them separately reforestation unless intensive site preparation and was not practical at the scale used. maintenance measures are applied. Mulching around Included in this unit are small areas of Medco soils on seedlings helps to maintain the moisture supply in concave slopes, Rock outcrop on ridges and convex summer and minimizes competition from undesirable slopes, poorly drained soils near drainageways and on understory plants. concave slopes, and soils that are similar to the McNull soil The main limitations affecting livestock grazing are but have bedrock at a depth of more than 40 inches. Also compaction and erosion. The McMullin soil also is limited included are small areas of soils that are similar to the by droughtiness and the depth to bedrock. The vegetation McMullin soil but have bedrock at a depth of less than 12 or suitable for grazing includes Idaho fescue, tall trisetum, and more than 20 inches, areas of soils that are similar to the western fescue on the McNull soil and bluebunch McNull and McMullin soils but have more than 35 percent wheatgrass, Lemmon needlegrass, and pine bluegrass on rock fragments, and McNull and McMullin soils that have the McMullin soil. If the range is overgrazed, the proportion slopes of less than 35 or more than 60 percent. Included of preferred forage plants decreases and the proportion of areas make up about 15 percent of the total acreage. less preferred forage plants increases. Grazing should be The McNull soil is moderately deep and well drained. It delayed until the more desirable forage plants have formed in colluvium derived dominantly from andesite, tuff, achieved enough growth to withstand grazing pressure and and breccia. Typically, the surface is covered with a layer of the soils are firm enough to withstand trampling by needles, leaves, and twigs about 1 inch thick. The surface livestock. layer is dark reddish brown gravelly loam about 6 inches Suitable management practices on this unit include thick. The upper 6 inches of the subsoil is dark reddish proper grazing use, deferred grazing, rotation grazing, brown clay loam. The lower 20 inches is dark reddish brown and brush control. Mechanical treatment may not be cobbly clay. Weathered bedrock is at a depth of about 32 practical in all areas because of the included Rock inches. The depth to bedrock ranges from 20 to 40 inches. outcrop and stony soils. In some areas the surface layer is stony or cobbly. Thinning, logging, and fire reduce the density of the Permeability is slow in the McNull soil. Available water overstory canopy and increase the production of capacity is about 4 inches. The effective rooting depth is understory vegetation. Areas that support a large amount 20 to 40 inches. Runoff is rapid, and the hazard of water of competing vegetation can be improved by prescribed erosion is high. burning or by chemical or mechanical treatment. Seeding The McMullin soil is shallow and well drained. It formed disturbed areas to suitable plants increases forage in colluvium derived dominantly from andesite, tuff, and production and reduces the risk of erosion. The McMullin breccia. Typically, the surface layer is dark reddish brown soil is poorly suited to seeding, however, because of gravelly loam about 7 inches thick. The subsoil is dark droughtiness and the depth to bedrock. reddish brown gravelly clay loam about 10 inches thick. This unit is limited as a site for livestock watering Bedrock is at a depth of about 17 inches. The depth to ponds and other water impoundments because of the bedrock ranges from 12 to 20 inches. In some areas the slope and the depth to bedrock. surface layer is stony. The vegetative site in areas of the McNull soil is Permeability is moderate in the McMullin soil. Pine-Douglas Fir-Fescue, and the one in areas of the Available water capacity is about 2 inches. The effective may be impassable during rainy periods. Logging roads rooting depth is 12 to 20 inches. Runoff is rapid, and the require suitable surfacing for year-round use. hazard of water erosion is high. A high temperature in the surface layer and an This unit is used for timber production, livestock insufficient moisture supply in summer increase the seedling grazing, and wildlife habitat. mortality rate. To compensate for the expected high The McNull soil is suited to the production of Douglas fir mortality rate, the larger seedlings or a greater number of and ponderosa pine. Other species that grow on this unit seedlings should be planted. When the timber is harvested, include incense cedar, California black oak, and Pacific leaving some of the larger trees unharvested provides madrone. The understory vegetation includes Pacific shade for seedlings. The seedling mortality rate also can be serviceberry, tall Oregongrape, and California fescue. reduced by providing artificial shade for seedlings. On the basis of a 100-year site curve, the mean site Reforestation can be accomplished by planting Douglas fir index for Douglas fir is 95 on the McNull soil. The yield at and ponderosa pine seedlings. culmination of the mean annual increment is 4,620 cubic Undesirable plants limit natural or artificial feet per acre in a fully stocked, even-aged stand of trees at reforestation unless intensive site preparation and 60 years and 37,120 board feet per acre (Scribner rule) at maintenance measures are applied. Mulching around 160 years. On the basis of a 50-year curve, the mean site seedlings helps to maintain the moisture supply in index is 70. summer and minimizes competition from undesirable The main limitations affecting timber production on the understory plants. McNull soil are the slope, erosion, compaction, seedling The main limitations affecting livestock grazing are the mortality, and plant competition. Also, the bedrock slope, erosion, and compaction. The McMullin soil also is restricts root growth. As a result, windthrow is a hazard. limited by droughtiness and the depth to bedrock. The Wheeled and tracked logging equipment can be used in vegetation suitable for grazing includes Idaho fescue, tall the less sloping areas, but cable yarding generally is safer trisetum, and western fescue on the McNull soil and Idaho and results in less surface disturbance. Using standard fescue, bluebunch wheatgrass, and pine bluegrass on the wheeled and tracked equipment when the soil is moist McMullin soil. If the range is overgrazed, the proportion of causes rutting and compaction. Puddling can occur when preferred forage plants decreases and the proportion of the soil is wet. Using low-pressure ground equipment less preferred forage plants increases. Grazing should be causes less damage to the soil and helps to maintain delayed until the more desirable forage plants have productivity. Compaction can be minimized by using achieved enough growth to withstand grazing pressure and suitable methods of harvesting, laying out skid trails in the soils are firm enough to withstand trampling by advance, and harvesting timber when the soil is least livestock. susceptible to compaction. Ripping skid trails and landings Suitable management practices on this unit include when the soil is dry can improve the growth of plants. proper grazing use, deferred grazing, rotation grazing, and Properly designed road drainage systems that include brush control. Mechanical treatment generally is not carefully located culverts help to control erosion. Seeding, practical because of the slope and the included areas of mulching, and benching areas that have been cut and filled Rock outcrop and stony soils. also help to control erosion. Steep yarding paths, skid trails, The suitability of this unit for seeding is poor. The main and firebreaks are subject to rilling and gullying unless they limitations affecting seeding are the slope, droughtiness, are protected by a plant cover or adequate water bars, or and the depth to bedrock in the McMullin soil. both. Cutbanks occasionally slump when the soil is Thinning, logging, and fire reduce the density of the saturated. overstory canopy and increase the production of Constructing logging roads on the steeper slopes can understory vegetation. Areas that support a large amount result in a high risk of erosion. Building the roads at of competing vegetation can be improved by prescribed midslope requires extensive cutting and filling and removes burning or by chemical or mechanical treatment. land from production. Material that is discarded when the This unit is limited as a site for livestock watering roads are built can damage vegetation and is a potential ponds and other water impoundments because of the source of sedimentation. If the material becomes saturated, slope and the depth to bedrock. avalanches of debris can occur. End hauling of the waste The vegetative site in areas of the McNull soil is material minimizes damage to the vegetation downslope Pine-Douglas Fir-Fescue, and the one in areas of the and reduces the risk of sedimentation. Skid trails and McMullin soil is Shallow Mountain Slopes, 22- to 30-inch unsurfaced roads precipitation zone. 117G-McNull-McMullin complex, 35 to 60 percent This unit is used for timber production, livestock north slopes. This map unit is on hillslopes. Elevation is grazing, and wildlife habitat. 1,500 to 4,000 feet. The mean annual precipitation is 20 to The McNull soil is suited to the production of Douglas fir 40 inches, the mean annual temperature is 45 to 52 and ponderosa pine. Other species that grow on this unit degrees F, and the average frost-free period is 100 to 160 include incense cedar, California black oak, and Pacific days. The native vegetation on the McNull soil is mainly madrone. The understory vegetation includes creambush conifers and hardwoods and an understory of grasses, oceanspray, common snowberry, and tall Oregongrape. shrubs, and forbs. That on the McMullin soil is mainly On the basis of a 100-year site curve, the mean site grasses, shrubs, and forbs. index for Douglas fir is 105 on the McNull soil. The yield at This unit is about 55 percent McNull soil and 30 percent culmination of the mean annual increment is 5,460 cubic McMullin soil. The components of this unit occur as areas feet per acre in a fully stocked, even-aged stand of trees at so intricately intermingled that mapping them separately 60 years and 45,600 board feet per acre (Scribner rule) at was not practical at the scale used. 150 years. On the basis of a 50-year curve, the mean site Included in this unit are small areas of Medco soils on index is 80. concave slopes, Rock outcrop on ridges and convex The main limitations affecting timber production on the slopes, poorly drained soils near drainageways and on McNull soil are the slope, erosion, compaction, and plant concave slopes, and soils that are similar to the McNull soil competition. Also, the bedrock restricts root growth. As a but have bedrock at a depth of more than 40 inches. Also result, windthrow is a hazard. included are small areas of soils that are similar to the Wheeled and tracked logging equipment can be used in McMullin soil but have bedrock at a depth of less than 12 or the less sloping areas, but cable yarding generally is safer more than 20 inches, soils that are similar to the McNull and results in less surface disturbance. Using standard and McMullin soils but have more than 35 percent rock wheeled and tracked equipment when the soil is moist fragments, and McNull and McMullin soils that have slopes causes rutting and compaction. Puddling can occur when of less than 35 or more than 60 percent. Included areas the soil is wet. Using low-pressure ground equipment make up about 15 percent of the total acreage. causes less damage to the soil and helps to maintain The McNull soil is moderately deep and well drained. It productivity. Compaction can be minimized by using formed in colluvium derived dominantly from andesite, tuff, suitable methods of harvesting, laying out skid trails in and breccia. Typically, the surface is covered with a layer of advance, and harvesting timber when the soil is least needles, leaves, and twigs about 1 inch thick. The surface susceptible to compaction. Ripping skid trails and landings layer is dark reddish brown loam about 6 inches thick. The when the soil is dry can improve the growth of plants. upper 6 inches of the subsoil is dark reddish brown clay Properly designed road drainage systems that include loam. The lower 20 inches is dark reddish brown cobbly carefully located culverts help to control erosion. Seeding, clay. Weathered bedrock is at a depth of about 32 inches. mulching, and benching areas that have been cut and filled The depth to bedrock ranges from 20 to 40 inches. In some also help to control erosion. Steep yarding paths, skid trail, areas the surface layer is stony or cobbly. and firebreaks are subject to rilling and gullying unless they Permeability is slow in the McNull soil. Available water are protected by a plant cover or adequate water bars, or capacity is about 4 inches. The effective rooting depth is both. Cutbanks occasionally slump when the soil is 20 to 40 inches. Runoff is rapid, and the hazard of water saturated. erosion is high. Constructing logging roads on the steeper slopes can The McMullin soil is shallow and well drained. It formed result in a high risk of erosion. Building the roads at in colluvium derived dominantly from andesite, tuff, and midslope requires extensive cutting and filling and removes breccia. Typically, the surface layer is dark reddish brown land from production. Material that is discarded when the gravelly loam about 7 inches thick. The subsoil is dark roads are built can damage vegetation and is a potential reddish brown gravelly clay loam about 10 inches thick. source of sedimentation. If the material becomes saturated, Bedrock is at a depth of about 17 inches. The depth to avalanches of debris can occur. End hauling of the waste bedrock ranges from 12 to 20 inches. In some areas the material minimizes damage to the vegetation downslope surface layer is stony. and reduces the risk of sedimentation. Skid trails and Permeability is moderate in the McMullin soil. Available unsurfaced roads may be impassable during rainy periods. water capacity is about 2 inches. The effective rooting depth Logging roads require suitable surfacing for year-round is 12 to 20 inches. Runoff is rapid, and the hazard of water use. erosion is high. Undesirable plants limit natural or artificial reforestation unless intensive site preparation and maintenance measures are applied. Reforestation can be This unit is about 55 percent McNull soil and 35 accomplished by planting Douglas fir and ponderosa pine percent Medco soil. The components of this unit occur as seedlings. Mulching around seedlings helps to maintain the areas so intricately intermingled that mapping them moisture supply in summer and minimizes competition from separately was not practical at the scale used. undesirable understory plants. Included in this unit are small areas of McMullin soils on The main limitations affecting livestock grazing are the ridges and convex slopes, poorly drained soils near slope, erosion, and compaction. The McMullin soil also is drainageways, soils that are similar to the McNull and limited by droughtiness and the depth to bedrock. The Medco soils but have bedrock at a depth of more than 40 vegetation suitable for grazing includes western fescue, inches, and soils that are similar to the Medco soil but are mountain brome, and tall trisetum on the McNull soil and 18 to 30 inches deep to a dense layer of clay. Also included Idaho fescue and pine bluegrass on the McMullin soil. If the are small areas of soils that have slopes of less than 12 or range is overgrazed, the proportion of preferred forage more than 50 percent. Included areas make up about 10 plants decreases and the proportion of less preferred percent of the total acreage. forage plants increases. Grazing should be delayed until The McNull soil is moderately deep and well drained. It the more desirable forage plants have achieved enough formed in colluvium derived dominantly from andesite, tuff, growth to withstand grazing pressure and the soils are firm and breccia. Typically, the surface is covered with a layer of enough to withstand trampling by livestock. needles, leaves, and twigs about 1 inch thick. The surface Suitable management practices on this unit include layer is dark reddish brown gravelly loam about 6 inches proper grazing use, deferred grazing, rotation grazing, and thick. The upper 6 inches of the subsoil is dark reddish brush control. Areas that support a large amount of brown clay loam. The lower 20 inches is dark reddish brown competing vegetation can be improved by chemical or cobbly clay. Weathered bedrock is at a depth of about 32 mechanical treatment. The use of ground equipment inches. The depth to bedrock ranges from 20 to 40 inches. generally is not practical because of the slope and the In some areas the surface layer is stony or cobbly. included areas of Rock outcrop and stony soils: Permeability is slow in the McNull soil. Available water The suitability of this unit for seeding is poor. The main capacity is about 4 inches. The effective rooting depth is limitations are the slope, droughtiness, and the depth to 20 to 40 inches. Runoff is medium or rapid, and the bedrock in the McMullin soil. The plants selected for hazard of water erosion is moderate or high. seeding should be those that meet the seasonal The Medco soil is moderately deep and moderately well requirements of livestock or wildlife, or both. drained. It formed in colluvium derived dominantly from Thinning, logging, and fire reduce the density of the andesite, tuff, arid breccia. Typically, the surface layer is overstory canopy and increase the production of very dark brown and very dark grayish brown cobbly clay understory vegetation. Areas that support a large amount loam about 7 inches thick. The next layer is very dark of competing vegetation can be improved by prescribed grayish brown cobbly clay loam about 5 inches thick. The burning or by chemical or mechanical treatment. subsoil is brown clay about 18 inches thick. Weathered This unit is limited as a site for livestock watering bedrock is at a depth of about 30 inches. The depth to ponds and other water impoundments because of the bedrock ranges from 20 to 40 inches. In some areas the slope and the depth to bedrock. surface layer is stony. The vegetative site in areas of the McNull soil is Permeability is very slow in the Medco soil. Available Douglas Fir Forest, and the one in areas of the water capacity is about 4 inches. The effective rooting depth McMullin soil is Droughty North, 18- to 35-inch is limited by a dense layer of clay at a depth of 6 to 18 precipitation zone. inches. Runoff is medium or rapid, and the hazard of water erosion is moderate or high. The water table, which is 118E-McNull-Medco complex, 12 to 50 pe rcent perched above the layer of clay, is at a depth of 0.5 foot to slopes. This map unit is on hillslopes. Elevation is 1,500 to 1.5 feet from December through March. 4,000 feet. The mean annual precipitation is 20 to 35 This unit is used mainly for livestock grazing or wildlife inches, the mean annual temperature is 45 to 52 degrees F, habitat. The McNull soil also is used for timber production. and the average frost-free period is 100 to 160 days. The The McNull soil is suited to the production of Douglas fir native vegetation on the McNull soil is mainly conifers and and ponderosa pine. Other species that grow on this unit hardwoods and an understory of grasses, shrubs, and include incense cedar, California black oak, and Pacific forbs. That on the Medco soil is mainly hardwoods and an madrone. The understory vegetation includes Pacific understory of grasses, shrubs, and forbs. serviceberry, tall Oregongrape, and California fescue. On the basis of a 100-year site curve, the mean site seedlings helps to maintain the moisture supply in index for Douglas fir is 95 on the McNull soil. The yield at summer and minimizes competition from undesirable culmination of the mean annual increment is 4,620 cubic understory plants. feet per acre in a fully stocked, even-aged stand of trees at The main limitations affecting livestock grazing are 60 years and 37,120 board feet per acre (Scribner rule) at compaction, erosion, and the slope. The Medco soil also is 160 years. On the basis of a 50-year curve, the mean site limited by cobbles on the surface and wetness in winter and index is 70. spring. The vegetation suitable for grazing includes Idaho The main limitations affecting timber production on the fescue, tall trisetum, and western fescue on the McNull soil McNull soil are erosion, compaction, seedling mortality, and and Idaho fescue, bluebunch wheatgrass, and pine plant competition. Also, the bedrock restricts root growth. bluegrass on the Medco soil. If the range is overgrazed, the As a result, windthrow is a hazard. proportion of preferred forage plants decreases and the Wheeled and tracked logging equipment can be used in proportion of less preferred forage plants increases. the less sloping areas, but cable yarding generally is safer A planned grazing system that includes timely deferment in the more sloping areas and results in less surface of grazing, rotation grazing, and proper livestock distribution disturbance. Using standard wheeled and tracked helps to prevent overgrazing of the understory and damage equipment when the soil is moist causes rutting and to the soils. Because the Medco soil remains wet for long compaction. Puddling can occur when the soil is wet. Using periods in spring, grazing should be delayed until the more low-pressure ground equipment causes less damage to the desirable forage plants have achieved enough growth to soil and helps to maintain productivity. Compaction can be withstand grazing pressure and the soil is firm enough to minimized by using suitable methods of harvesting, laying withstand trampling by livestock. Compaction can be out skid trails in advance, and harvesting timber when the minimized by grazing first in the areas that dry out earliest. soil is least susceptible to compaction. Ripping skid trails Thinning, logging, and fire reduce the density of the and landings when the soil is dry can improve the growth of overstory canopy and increase the production of plants. understory vegetation. Areas that support a large amount Properly designed road drainage systems that include of competing vegetation can be improved by prescribed carefully located culverts help to control erosion. Areas that burning or by chemical or mechanical treatment. In places have been cut and filled are easily eroded unless they are the use of ground equipment is limited by the seasonal treated. Seeding, mulching, and benching these areas help wetness, the slope, and the included areas of stony soils to control erosion. Steep yarding paths, skid trails, and and Rock outcrop. firebreaks are subject to rilling and gullying unless they are Range seeding is suitable on the Medco soil if the site is protected by a plant cover or adequate water bars, or both. in poor condition. The main limitations are wetness in winter The Medco soil, which occurs throughout the unit, is and spring and droughtiness in summer and fall. Seeding subject to severe slumping. Road failure and landslides are disturbed areas to suitable plants increases forage likely to occur after road construction and clearcutting. production and reduces the risk of erosion. The plants Slumping can be minimized by constructing logging roads in selected for seeding should be those that meet the the less sloping areas, on better suited soils if practical, and seasonal requirements of livestock or wildlife, or both. by installing properly designed road drainage systems. Skid The vegetative site in areas of the McNull soil is trails and unsurfaced roads may be impassable during rainy Pine-Douglas Fir-Fescue, and the one in areas of the periods. Logging roads require suitable surfacing for Medco soil is Loamy Hills, 20- to 35-inch precipitation year-round use. zone. A high temperature in the surface layer and an insufficient moisture supply in summer increase the seedling 119F-McNull-Medco complex, high precipitation, 12 mortality rate, especially on south- and southwest-facing to 50 percent slopes. This map unit is on hillslopes. slopes. To compensate for the expected high mortality rate, Elevation is 2,500 to 4,000 feet. The mean annual the larger seedlings or a greater number of seedlings should precipitation is 35 to 40 inches, the mean annual be planted. When the timber is harvested, leaving some of temperature is 45 to 52 degrees F, and the average the larger trees unharvested provides shade for seedlings. frost-free period is 100 to 160 days. The native vegetation Reforestation can be accomplished by planting Douglas fir is mainly conifers and hardwoods and an understory of and ponderosa pine seedlings. grasses, shrubs, and forbs. Undesirable plants limit natural or artificial This unit is about 50 percent McNull soil and 35 reforestation unless intensive site preparation and maintenance measures are applied. Mulching around percent Medco soil. The components of this unit occur as index for Douglas fir is 95 on the McNull soil. The yield at areas so intricately intermingled that mapping them culmination of the mean annual increment is 4,620 cubic separately was not practical at the scale used. feet per acre in a fully stocked, even-aged stand of trees at Included in this unit are small areas of McMullin soils on 60 years and 37,120 board feet per acre (Scribner rule) at ridges and convex slopes, poorly drained soils near 160 years. On the basis of a 50-year curve, the mean site drainageways, soils that are similar to the McNull and index is 70. Medco soils but have bedrock at a depth of more than 40 On the basis of a 100-year site curve, the mean site inches, and soils that are similar to the Medco soil but are index for Douglas fir is 85 on the Medco soil. The yield at 18 to 30 inches deep to a dense layer of clay. Also included culmination of the mean annual increment is 4,480 cubic are small areas of McNull and Medco soils that have slopes feet per acre in a fully stocked, even-aged stand of trees at of less than 12 or more than 50 percent. Included areas 70 years and 27,520 board feet per acre (Scribner rule) at make up about 15 percent of the total acreage. 160 years. On the basis of a 50-year curve, the mean site The McNull soil is moderately deep and well drained. It index is 65. formed in colluvium derived dominantly from andesite, tuff, The main limitations affecting timber production are and breccia. Typically, the surface is covered with a layer of erosion, compaction, plant competition, and seedling needles, leaves, and twigs about 1 inch thick. The surface mortality. The bedrock in both soils and the dense layer of layer is dark reddish brown loam about 6 inches thick. The clay in the Medco soil restrict root growth. As a result, upper 6 inches of the subsoil is dark reddish brown clay windthrow is a hazard. The Medco soil also is limited by loam. The lower 20 inches is dark reddish brown cobbly seasonal wetness and slumping. clay. Weathered bedrock is at a depth of about 32 inches. The perched seasonal high water table in the Medco soil The depth to bedrock ranges from 20 to 40 inches. In some limits the use of equipment to dry periods. Wheeled and areas the surface layer is stony or cobbly. tracked logging equipment can be used in the less sloping Permeability is slow in the McNull soil. Available water areas, but cable yarding generally is safer in the more capacity is about 4 inches. The effective rooting depth is sloping areas and results in less surface disturbance. Using 20 to 40 inches. Runoff is medium or rapid, and the standard wheeled and tracked equipment when the soils are hazard of water erosion is moderate or high. moist causes rutting and compaction. Puddling can occur The Medco soil is moderately deep and moderately well wh6n the soils are wet. Using low-pressure ground drained. It formed in colluvium derived dominantly from equipment causes less damage to the soils and helps to andesite, tuff, and breccia. Typically, the surface layer is maintain productivity. Compaction can be minimized by very dark brown cobbly clay loam about 7 inches thick. The using suitable methods of harvesting, laying out skid trails in next layer is dark brown cobbly clay loam about 6 inches advance, and harvesting timber when the soils are least thick. The subsoil is brown clay about 22 inches thick. susceptible to compaction. Ripping skid trails and landings Weathered bedrock is at a depth of about 35 inches. The when the soils are dry can improve the growth of plants. depth to bedrock ranges from 20 to 40 inches. In some The Medco soil is subject to severe slumping. Road areas the surface layer is stony. failure and landslides are likely to occur after road Permeability is very slow in the Medco soil. Available construction and clearcutting. Slumping can be minimized water capacity is about 4 inches. The effective rooting depth by constructing logging roads in the less sloping areas, on is limited by a dense layer of clay at a depth of 6 to 18 better suited soils if practical, and by installing properly inches. Runoff is medium or rapid, and the hazard of water designed road drainage systems. Skid trails and erosion is moderate or high. The water table, which is unsurfaced roads may be impassable during rainy periods. perched above the layer of clay, is at a depth of 0.5 foot to Logging roads require suitable surfacing for year-round 1.5 feet from December through March. use. This unit is used for timber production, livestock Properly designed road drainage systems that include grazing, and wildlife habitat. carefully located culverts help to control erosion. Areas that This unit is suited to the production of Douglas fir and have been cut and filled are easily eroded unless they are ponderosa pine. Other species that grow on this unit treated. Seeding, mulching, and benching these areas help include incense cedar, California black oak, and Pacific to control erosion. Steep yarding paths, skid trails, and madrone. The understory vegetation includes Pacific firebreaks are subject to rilling and gullying unless they are serviceberry, tall Oregongrape, and California fescue. protected by a plant cover or adequate water bars, or both. On the basis of a 100-year site curve, the mean site Undesirable plants limit natural or artificial reforestation unless intensive site preparation and maintenance measures are applied. Reforestation can be vegetation is mainly hardwoods and an understory of accomplished by planting Douglas fir and ponderosa pine grasses, shrubs, and forbs. seedlings. Mulching around seedlings helps to maintain the Typically, the surface layer is very dark brown and very moisture supply in summer and minimizes competition from dark grayish brown clay loam about 7 inches thick. The undesirable understory plants. next layer is very dark grayish brown cobbly clay loam A high temperature in the surface layer and an about 5 inches thick. The subsoil is brown clay about 18 insufficient moisture supply in summer increase the inches thick. Weathered bedrock is at a depth of about 30 seedling mortality rate, especially on south- and inches. The depth to bedrock ranges from 20 to 40 inches. southwest-facing slopes. To compensate for the expected In some areas the surface layer is cobbly or stony. high mortality rate, the larger seedlings or a greater number Included in this unit are small areas of Carney and of seedlings should be planted. When the timber is McNull soils, McMullin soils and Rock outcrop on ridges and harvested, leaving some of the larger trees unharvested convex slopes, soils that are similar to the Medco soil but provides shade for seedlings. The seedling mortality rate are poorly drained and are near drainageways and on also can be reduced in the more sloping areas by providing concave slopes, and soils that are similar to the Medco soil artificial shade for seedlings. The seasonal wetness of the but have bedrock at a depth of more than 40 inches. Also Medco soil increases the seedling mortality rate. Also, included are small areas of Medco soils that have slopes of seedlings planted in the less fertile clayey subsoil grow more than 7 percent. Included areas make up about 15 poorly. percent of the total acreage. The main limitations affecting livestock grazing are Permeability is very slow in the Medco soil. Available compaction and erosion on both soils and the seasonal water capacity is about 4 inches. The effective rooting wetness of the Medco soil. The native vegetation suitable depth is limited by a dense layer of clay at a depth of 6 to for grazing includes Idaho fescue, tall trisetum, and western 18 inches. Runoff is slow, and the hazard of water erosion fescue. If the understory is overgrazed, the proportion of is slight. The water table, which is perched above the layer preferred forage plants decreases and the proportion of less of clay, is at a depth of 0.5 foot to 1.5 feet from December preferred forage plants increases. through March. A planned grazing system that includes timely deferment This unit is used for hay and pasture, livestock of grazing, rotation grazing, and proper livestock distribution grazing, and wildlife habitat. helps to prevent overgrazing of the understory and damage This unit is suited to hay and pasture. It is limited mainly to the soils. Because the Medco soil remains wet for long by wetness in winter and spring, droughtiness in summer periods in spring, grazing should be delayed until the soil is and fall, and the very slow permeability in the subsoil. In firm and the more desirable forage plants have achieved summer, irrigation is needed for the maximum production of enough growth to withstand grazing pressure. Compaction hay and pasture. Sprinkler irrigation is the best method of can be minimized by grazing first in the areas that dry out applying water. This method permits an even, controlled earliest. application of water, helps to prevent excessive runoff, and Thinning, logging, and fire reduce the density of the minimizes the risk of erosion. Border and contour flood overstory canopy and increase the production of irrigation systems also are suitable in the less sloping areas. understory vegetation. Areas that support a large amount For the efficient application and removal of surface irrigation of competing vegetation can be improved by prescribed water, land leveling is needed; however, deep cuts can burning or by chemical or mechanical treatment. Seeding expose the bedrock or the clayey subsoil. To prevent disturbed areas to suitable plants increases forage overirrigation and excessive erosion or development of a production and reduces the risk of erosion. perched water table, applications of irrigation water should be adjusted to the available water capacity, the rate of water intake, and the needs of the crop. Wetness limits the choice of suitable forage plants and The vegetative site is Pine-Douglas Fir-Fescue. the period of cutting or grazing and increases the risk of winterkill. Proper stocking rates, pasture rotation, and 120B-Medco clay loam, 3 to 7 percent slopes. restricted grazing during wet periods help to keep pastures This moderately deep, moderately well drained soil is on in good condition and protect the soil from erosion. Grazing hillslopes. It formed in alluvium and colluvium derived when the soil is wet results in compaction of the surface dominantly from andesite tuff, and breccia. Elevation is layer, poor filth, and excessive runoff. Periodic mowing and 1,500 to 4,000 feet. The mean annual precipitation is 20 clipping help to maintain uniform plant growth, discourage to 35 inches, the mean annual temperature is 45 to 52 selective degrees F, and the average frost-free period is 100 to 160 days. The native grazing, and reduce the extent of clumpy growth. about 18 inches thick. Weathered bedrock is at a depth of The ability of tile drains to remove subsurface water about 30 inches. The depth to bedrock ranges from 20 to from the soil is limited because of the very slow 40 inches. In some areas the surface layer is cobbly or permeability. Land smoothing and open ditches can stony. reduce surface wetness. Included in this unit are small areas of Carney and McNull Fertilizer is needed to ensure the optimum growth of soils, McMullin soils and Rock outcrop on ridges and convex grasses and legumes. Grasses respond to nitrogen, and slopes, poorly drained soils near drainageways and on legumes respond to sulfur and phosphorus. concave slopes, and soils that are similar to the Medco soil The main limitations affecting livestock grazing are but have bedrock at a depth of more than 40 inches. Also compaction, wetness in winter and spring, and included are small areas of Medco soils that have slopes of droughtiness in summer and fall. The vegetation suitable less than 7 or more than 12 percent. Included areas make for grazing includes California oatgrass, Idaho fescue, and up about 15 percent of the total acreage. bluegrass. If the range is overgrazed, the proportion of Permeability is very slow in the Medco soil. Available preferred forage plants decreases and the proportion of water capacity is about 4 inches. The effective rooting depth less preferred forage plants increases. is limited by a dense layer of clay at a depth of 6 to 18 Because this soil remains wet for long periods in spring, inches. Runoff is medium, and the hazard of water erosion is grazing should be delayed until the more desirable forage moderate. The water table, which is perched above the layer plants have achieved enough growth to withstand grazing of clay, is at a depth of 0.5 foot to 1.5 feet from December pressure and the soil is firm enough to withstand trampling through March. by livestock. Compaction can be minimized by grazing first This unit is used for hay and pasture, livestock in the areas that dry out earliest. grazing, and wildlife habitat. Suitable management practices on this unit include This unit is suited to hay and pasture. It is limited mainly proper grazing use, deferred grazing, rotation grazing, and by the slope, wetness in winter and spring, droughtiness in brush control. Areas that support a large amount of summer and fall, and the very slow permeability in the competing vegetation can be improved by chemical or subsoil. In summer, irrigation is needed for the maximum mechanical treatment. The use of ground equipment on this production of hay and pasture. Sprinkler irrigation is the best unit should be limited to dry periods. method of applying water. This method permits an even, Range seeding is suitable if the site is in poor controlled application of water, helps to prevent excessive condition. The main limitations are wetness in winter and runoff, and minimizes the risk of erosion. To prevent spring and droughtiness in summer and fall. The plants overirrigation and excessive erosion or development of a selected for seeding should be those that meet the perched water table, applications of irrigation water should seasonal requirements of livestock or wildlife, or both. be adjusted to the available water capacity, the rate of water This unit is limited as a site for livestock watering intake, and the needs of the crop. ponds and other water impoundments because of the Wetness limits the choice of suitable forage plants and depth to bedrock. the period of cutting or grazing and increases the risk of The vegetative site is Clayey Hills, 20- to 35-inch winterkill. Proper stocking rates, pasture rotation, and precipitation zone. restricted grazing during wet periods help to keep pastures in good condition and protect the soil from erosion. Grazing 120C-Medco clay loam, 7 to 12 percent slopes. when the soil is wet results in compaction of the surface This moderately deep, moderately well drained soil is on layer, poor tilth, and excessive runoff. Periodic mowing and hillslopes. It formed in alluvium and colluvium derived clipping help to maintain uniform plant growth, discourage dominantly from andesite, tuff, and breccia. Elevation is selective grazing, and reduce the extent of clumpy growth. 1,500 to 4,000 feet. The mean annual precipitation is 20 The ability of tile drains to remove subsurface water from to 35 inches, the mean annual temperature is 45 to 52 the soil is limited because of the very slow permeability and degrees F, and the average frost-free period is 100 to the slope. Wetness can be reduced by interceptor drains. 160 days. The native vegetation is mainly hardwoods Fertilizer is needed to ensure the optimum growth of and an understory of grasses, shrubs, and (orbs. grasses and legumes. Grasses respond to nitrogen, and Typically, the surface layer is very dark brown and very legumes respond to sulfur and phosphorus. dark grayish brown clay loam about 7 inches thick. The The main limitations affecting livestock grazing are next layer is very dark grayish brown cobbly clay loam compaction, wetness in winter and spring, and about 5 inches thick. The subsoil is brown clay droughtiness in summer and fall. The vegetation suitable Medco soils that have slopes of less than 12 or more for grazing includes California oatgrass, Idaho fescue, and than 50 percent. Included areas make up about 15 bluegrass. If the range is overgrazed, the proportion of percent of the total acreage. preferred forage plants decreases and the proportion of Permeability is very slow in the Medco soil. Available less preferred forage plants increases. water capacity is about 4 inches. The effective rooting Because this soil remains wet for long periods in spring, depth is limited by a dense layer of clay at a depth of 6 to grazing should be delayed until the more desirable forage 18 inches. Runoff is medium or rapid, and the hazard of plants have achieved enough growth to withstand grazing water erosion is moderate or high. The water table, which is pressure and the soil is firm enough to withstand trampling perched above the layer of clay, is at a depth of 0.5 foot to by livestock. Compaction can be minimized by grazing first 1.5 feet from December through March. in the areas that dry out earliest. This unit is used mainly for livestock grazing or Suitable management practices on this unit include wildlife habitat. The less sloping parts of a few areas are proper grazing use, deferred grazing, rotation grazing, and used for pasture. brush control. Areas that support a large amount of The main limitations affecting livestock grazing are competing vegetation can be improved by chemical or compaction, erosion, wetness in winter and spring, mechanical treatment. The use of ground equipment on this droughtiness in summer and fall, the cobbly surface layer, unit should be limited to dry periods. and the slope. The vegetation suitable for grazing includes Range seeding is suitable if the site is in poor California oatgrass, Idaho fescue, and bluegrass. If the condition. The main limitations are wetness in winter and range is overgrazed, the proportion of preferred forage spring and droughtiness in summer and fall. The plants plants decreases and the proportion of less preferred selected for seeding should be those that meet the forage plants increases. seasonal requirements of livestock or wildlife, or both. Because this soil remains wet for long periods in spring, This unit is limited as a site for livestock watering grazing should be delayed until the more desirable forage ponds and other water impoundments because of the plants have achieved enough growth to withstand grazing slope and the depth to bedrock. pressure and the soil is firm enough to withstand trampling The vegetative site is Clayey Hills, 20- to 35-inch by livestock. Compaction can be minimized by grazing first precipitation zone. in the areas that dry out earliest. Suitable management practices on this unit include 121E-Medco cobbly clay loam, 12 to 50 percent north proper grazing use, deferred grazing, rotation grazing, and slopes. This moderately deep, moderately well drained soil brush control. Areas that support a large amount of is on hillslopes. It formed in alluvium and colluvium derived competing vegetation can be improved by chemical or dominantly from andesite, tuff, and breccia. Elevation is mechanical treatment. In some areas the use of ground 1,500 to 4,000 feet. The mean annual precipitation is 20 to equipment and access by livestock are limited by the 35 inches, the mean annual temperature is 45 to 52 seasonal wetness, the cobbles on the surface, and the degrees F, and the average frost-free period is 100 to 160 slope. days. The native vegetation is mainly hardwoods and an Range seeding is suitable if the site is in poor condition. understory of grasses, shrubs, and forbs. The main limitations are the cobbly surface layer, wetness Typically, the surface layer is very dark brown and very in winter and spring, and droughtiness in summer and fall. dark grayish brown cobbly clay loam about 7 inches thick. The plants selected for seeding should be those that meet The next layer is very dark grayish brown cobbly clay loam the seasonal requirements of livestock or wildlife, or both. about 5 inches thick. The subsoil is brown clay about 18 This unit is limited as a site for livestock watering inches thick. Weathered bedrock is at a depth of about 30 ponds and other water impoundments because of the inches. The depth to bedrock ranges from 20 to 40 inches. slope and the depth to bedrock. In some areas the surface layer is stony. The vegetative site is Clayey Hills, 20- to 35-inch Included in this unit are small areas of Carney and precipitation zone. McNull soils, McMullin soils and Rock outcrop on ridges and convex slopes, poorly drained soils near drainageways and 122E-Medco cobbly clay loam, 12 to 50 percent south on concave slopes, and soils that are similar to the Medco slopes. This moderately deep, moderately well drained soil soil but have bedrock at a depth of more than 40 inches. is on hillslopes. It formed in alluvium and colluvium derived Also included are small areas of dominantly from andesite, tuff, and breccia. Elevation is 1,500 to 4,000 feet. The mean annual precipitation is 20 to 35 inches, the mean annual temperature is 45 to 52 degrees F, and the average to graze in areas where access is limited. frost-free period is 100 to 160 days. The native Range seeding is suitable if the site is in poor condition. vegetation is mainly hardwoods and an understory of The main limitations are the cobbly surface layer, wetness in grasses, shrubs, and forbs. winter and spring, and droughtiness in summer and fall. The Typically, the surface layer is very dark brown and very plants selected for seeding should be those that meet the dark grayish brown cobbly clay loam about 7 inches thick. seasonal requirements of livestock or wildlife, or both. The next layer is very dark grayish brown cobbly clay loam This unit is limited as a site for livestock watering about 5 inches thick. The subsoil is brown clay about 18 ponds and other water impoundments because of the inches thick. Weathered bedrock is at a depth of about 30 slope and the depth to bedrock. inches. The depth to bedrock ranges from 20 to 40 inches. The vegetative site is Loamy Hills, 20- to 35-inch In some areas the surface layer is stony. precipitation zone. Included in this unit are small areas of Carney and McNull soils, McMullin soils and Rock outcrop on ridges and 123F-Medco clay loam, high precipitation, 12 to 50 convex slopes, poorly drained soils near drainageways and percent north slopes. This moderately deep, moderately on concave slopes, and soils that are similar to the Medco well drained soil is on hillslopes. It formed in colluvium soil but have bedrock at a depth of more than 40 inches. derived dominantly from andesite, tuff, and breccia. Also included are small areas of Medco soils that have Elevation is 2,500 to 4,000 feet. The mean annual slopes of less than 12 or more than 50 percent.. Included precipitation is 35 to 40 inches, the mean annual areas make up about 15 percent of the total acreage. temperature is 45 to 52 degrees F, and the average Permeability is very slow in the Medco soil. Available frost-free period is 100 to 150 days. The native vegetation is water capacity is about 4 inches. The effective rooting depth mainly conifers and hardwoods and an understory of is limited by a dense layer of clay at a depth of 6 to 18 grasses, shrubs, and forbs. inches. Runoff is medium or rapid, and the hazard of water Typically, the surface layer is very dark brown clay loam erosion is moderate or high. The water table, which is about 7 inches thick. The next layer is dark brown cobbly perched above the layer of clay, is at a depth of 0.5 foot to clay loam about 6 inches thick. The subsoil is brown clay 1.5 feet from December through March. about 22 inches thick. Weathered bedrock is at a depth of This unit is used mainly for livestock grazing or wildlife about 35 inches. The depth to bedrock ranges from 20 to 40 habitat. Some of the less sloping areas are used for pasture. inches. In some areas the surface layer is stony. The main limitations affecting livestock grazing are Included in this unit are small areas of McMullin soils on compaction, erosion, wetness in winter and spring, the ridges and convex slopes, poorly drained soils near cobbly surface layer, and the slope. The vegetation drainageways, and McNull soils on convex slopes. Also suitable for grazing includes bluebunch wheatgrass, Idaho included are small areas of soils that are similar to the fescue, and pine bluegrass. If the range is overgrazed, the Medco soil but have bedrock at a depth of more than 40 proportion of preferred forage plants decreases and the inches or are 18 to 30 inches deep to a dense layer of clay proportion of less preferred forage plants increases. and Medco soils that have slopes of less than 12 or more Because this soil remains wet for long periods in spring, than 50 percent. Included areas make up about 20 percent grazing should be delayed until the more desirable forage of the total acreage. plants have achieved enough growth to withstand grazing Permeability is very slow in the Medco soil. Available pressure and the soil is firm enough to withstand trampling water capacity is about 4 inches. The effective rooting depth by livestock. Compaction can be minimized by grazing first is limited by a dense layer of clay at a depth of 6 to 18 in the areas that dry out earliest. inches. Runoff is medium or rapid, and the hazard of water Suitable management practices on. this unit include erosion is moderate or high. The water table, which is proper grazing use, deferred grazing, rotation grazing, and perched above the layer of clay, is at a depth of 0.5 foot to brush control. Areas that support a large amount of 1.5 feet from December through March. competing vegetation can be improved by chemical or This unit is used for timber production, livestock mechanical treatment. In places the use of ground grazing, and wildlife habitat. equipment and access by livestock are limited by the This unit is suited to the production of Douglas fir and seasonal wetness, the cobbles on the surface, and the ponderosa pine. Other species that grow on this unit slope. Constructing trails or walkways allows livestock include incense cedar, California black oak, and Pacific madrone. The understory vegetation includes creambush oceanspray, common snowberry, and tall Oregongrape. On the basis of a 100-year site curve, the mean site compaction, erosion, and the seasonal wetness. The index for Douglas fir is 85. The yield at culmination of the native vegetation suitable for grazing includes western mean annual increment is 4,480 cubic feet per acre in a fescue, mountain brome, and tall trisetum. If the fully stocked, even-aged stand of trees at 70 years and understory is overgrazed, the proportion of preferred 27,520 board feet per acre (Scribner rule) at 160 years. On forage plants decreases and the proportion of less the basis of a 50-year curve, the mean site index is 65. preferred forage plants increases. The main limitations affecting timber production are A planned grazing system that includes timely deferment erosion, compaction, slumping, the seasonal wetness, and of grazing, rotation grazing, and proper livestock distribution plant competition. Also, the dense layer of clay restricts root helps to prevent overgrazing of the understory and damage growth. As a result, windthrow is a hazard. to the soil. Because the soil remains wet for long periods in The perched seasonal high water table limits the use of spring, grazing should be delayed until the soil is firm and equipment to dry periods. Wheeled and tracked logging the more desirable forage plants have achieved enough equipment can be used in the less sloping areas, but cable growth to withstand grazing pressure. Compaction can be yarding generally is safer in the more sloping areas and minimized by grazing first in the areas that dry out earliest. results in less surface disturbance. Using standard wheeled Thinning, logging, and fire reduce the density of the and tracked equipment when the soil is moist causes overstory canopy and increase the production of rutting and compaction. Puddling can occur when the soil is understory vegetation. Areas that support a large amount wet. Using low-pressure ground equipment causes less of competing vegetation can be improved by prescribed damage to the soil and helps to maintain productivity. burning or by chemical or mechanical treatment. Seeding Compaction can be minimized by using suitable methods of disturbed areas to suitable plants increases forage harvesting, laying out skid trails in advance, and harvesting production and reduces the risk of erosion. timber when the soil is least susceptible to compaction. The vegetative site is Douglas Fir Forest. Ripping skid trails and landings when the soil is dry can improve the growth of plants. 124F-Medco clay loam, high precipitation, 12 to 50 Properly designed road drainage systems that include percent south slopes. This moderately deep, moderately carefully located culverts help to control erosion. Areas that well drained soil is on hillslopes. It formed in colluvium have been cut and filled are easily eroded unless they are derived dominantly from andesite, tuff, and breccia. treated. Seeding, mulching, and benching these areas help Elevation is 2,500 to 4,000 feet. The mean annual to control erosion. Steep yarding paths, skid trails, and precipitation is 35 to 40 inches, the mean annual firebreaks are subject to rifling and gullying unless they are temperature is 45 to 52 degrees F, and the average protected by a plant cover or adequate water bars, or both. frost-free period is 100 to 150 days. The native vegetation is This unit is subject to severe slumping. Road failure and mainly conifers and hardwoods and an understory of landslides are likely to occur after road construction and grasses, shrubs, and forbs. clearcutting. Slumping can be minimized by constructing Typically, the surface layer is very dark brown clay loam logging roads in the less sloping areas, on better suited about 7 inches thick. The next layer is dark brown cobbly soils if practical, and by installing properly designed road clay loam about 6 inches thick. The subsoil is brown clay drainage systems. Skid trails and unsurfaced roads may be about 22 inches thick. Weathered bedrock is at a depth of impassable during rainy periods. Logging roads require about 35 inches. The depth to bedrock ranges from 20 to 40 suitable surfacing for year-round use. inches. In some areas the surface layer is stony. Undesirable plants limit natural or artificial reforestation Included in this unit are small areas of McMullin soils on unless intensive site preparation and maintenance ridges and convex slopes, poorly drained soils near measures are applied. Reforestation can be accomplished drainageways, and McNull soils on convex slopes. Also by planting Douglas fir and ponderosa pine seedlings. included are small areas of soils that are similar to the Mulching around seedlings helps to maintain the moisture Medco soil but have bedrock at a depth of more than 40 supply in summer and minimizes competition from inches or are 18 to 30 inches deep to a dense layer of clay undesirable understory plants. The seasonal wetness and Medco soils that have slopes of less than 12 or more increases the seedling mortality rate. Also, seedlings than 50 percent. Included areas make up about 20 percent planted in the less fertile clayey subsoil grow poorly. of the total acreage. The main limitations affecting livestock grazing are Permeability is very slow in the Medco soil. Available water capacity is about 4 inches. The effective rooting depth is limited by a dense layer of clay at a depth of 6 to 18 unsurfaced roads may be impassable during rainy inches. Runoff is medium or rapid, and the hazard of water periods. Logging roads require suitable surfacing for erosion is moderate or high. The water table, which is year-round use. perched above the layer of clay, is at a depth of 0.5 foot to Undesirable plants limit natural or artificial reforestation 1.5 feet from December through March. unless intensive site preparation and maintenance This unit is used for timber production, livestock measures are applied. Reforestation can be accomplished grazing, and wildlife habitat. by planting Douglas fir and ponderosa pine seedlings. This unit is suited to the production of Douglas fir and Mulching around seedlings helps to maintain the moisture ponderosa pine. Other species that grow on this unit supply in summer and minimizes competition from include incense cedar, California black oak, and Pacific undesirable understory plants. madrone. The understory vegetation includes Pacific A high temperature in the surface layer and an serviceberry, tall Oregongrape, and California fescue. insufficient moisture supply in summer increase the On the basis of a 100-year site curve, the mean site seedling mortality rate. To compensate for the expected index for Douglas fir is 85. The yield at culmination of the high mortality rate, the larger seedlings or a greater number mean annual increment is 4,480 cubic feet per acre in a of seedlings should be planted. When the timber is fully stocked, even-aged stand of trees at 70 years and harvested, leaving some of the larger trees unharvested 27,520 board feet per acre (Scribner rule) at 160 years. On provides shade for seedlings. The seedling mortality rate the basis of a 50-year curve, the mean site index is 65. also can be reduced by providing artificial shade for The main limitations affecting timber production are seedlings. The seasonal wetness increases the seedling erosion, compaction, slumping, the seasonal wetness, mortality rate. Also, seedlings planted in the less fertile plant competition, and seedling mortality. Also, the dense clayey subsoil grow poorly. layer of clay restricts root growth. As a result, windthrow The main limitations affecting livestock grazing are is a hazard. compaction, erosion, and the seasonal wetness. The The perched seasonal high water table limits the use of native vegetation suitable for grazing includes Idaho equipment to dry periods. Wheeled and tracked logging fescue, tall trisetum, and western fescue. If the equipment can be used in the less sloping areas, but cable understory is overgrazed, the proportion of preferred yarding generally is safer in the more sloping areas and forage plants decreases and the proportion of less results in less surface disturbance. Using standard wheeled preferred forage plants increases. and tracked equipment when the soil is moist causes rutting A planned grazing system that includes timely deferment and compaction. Puddling can occur when the soil is wet. of grazing, rotation grazing, and proper livestock distribution Using low-pressure ground equipment causes less damage helps to prevent overgrazing of the understory and damage to the soil and helps to maintain productivity. Compaction to the soil. Because the soil remains wet for long periods in can be minimized by using suitable methods of harvesting, spring, grazing should be delayed until the soil is firm and laying out skid trails in advance, and harvesting timber the more desirable forage plants have achieved enough when the soil is least susceptible to compaction. Ripping growth to withstand grazing pressure. Compaction can be skid trails and landings when the soil is dry can improve the minimized by grazing first in the areas that dry out earliest. growth of plants. Thinning, logging, and fire reduce the density of the Properly designed road drainage systems that include overstory canopy and increase the production of carefully located culverts help to control erosion. Areas that understory vegetation. Areas that support a large amount have been cut and filled are easily eroded unless they are of competing vegetation can be improved by prescribed treated. Seeding, mulching, and benching these areas help burning or by chemical or mechanical treatment. Seeding to control erosion. Steep yarding paths, skid trails, and disturbed areas to suitable plants increases forage firebreaks are subject to rilling and gullying unless they are production and reduces the risk of erosion. protected by a plant cover or adequate water bars, or both. The vegetative site is Pine-Douglas Fir-Fescue. This unit is subject to severe slumping. Road failure and landslides are likely to occur after road construction and 125C-Medco-McMullin complex, 1 to 12 percent clearcutting. Slumping can be minimized by constructing slopes. This map unit is on hillslopes. Elevation is 1,300 to logging roads in the less sloping areas, on better suited 4,000 feet. The mean annual precipitation is 20 to 35 soils if practical, and by installing properly inches, the mean annual temperature is 45 to 52 degrees F, designed road drainage systems. Skid trails and' and the average frost-free period is 100 to 160 days. The native vegetation on the Medco soil is mainly hardwoods and an understory of grasses, shrubs, on the surface, and droughtiness. The vegetation suitable and forbs. That on the McMullin soil is mainly grasses, for grazing includes California oatgrass, Idaho fescue, and shrubs, and forbs. bluegrass on the Medco soil and bluebunch wheatgrass and This unit is about 55 percent Medco soil and 30 pine bluegrass on the McMullin soil. If the range is percent McMullin soil. The components of this unit occur overgrazed, the proportion of preferred forage plants as areas so intricately intermingled that mapping them decreases and the proportion of less preferred forage plants separately was not practical at the scale used. increases. Included in this unit are small areas of Carney and Because the Medco soil remains wet for long periods in McNull soils, Rock outcrop on ridges and convex slopes, spring, grazing should be delayed until the more desirable and soils that are similar to the McMullin soil but have more forage plants have achieved enough growth to withstand than 35 percent rock fragments or have bedrock at a depth grazing pressure and the soil is firm enough to withstand of less than 12 or more than 20 inches. Also included are trampling by livestock. Compaction can be minimized by small areas of soils that are similar to the Medco soil but grazing first in the areas that dry out earliest. have bedrock at a depth of more than 40 inches, poorly Suitable management practices on this unit include drained soils near drainageways and on concave slopes, proper grazing use, deferred grazing, rotation grazing, and and Medco and McMullin soils that have slopes of more brush control. Areas that support a large amount of than 12 percent. Included areas make up about 15 percent competing vegetation can be improved by chemical or of the total acreage. mechanical treatment. In places the use of ground The Medco soil is moderately deep and moderately well equipment is limited by the seasonal wetness and the drained. It formed in colluvium derived dominantly from included areas of stony soils and Rock outcrop. andesite, tuff, and breccia. Typically, the surface layer is Range seeding is suitable on the Medco soil if the site is very dark brown and very dark grayish brown cobbly clay in poor condition. The main limitations are the cobbly loam about 7 inches thick. The next layer is very dark surface layer, wetness in winter and spring, and grayish brown cobbly clay loam about 5 inches thick. The droughtiness in summer and fall. The suitability of the subsoil is brown clay about 18 inches thick. Weathered McMullin soil for seeding is poor. The main limitations are bedrock is at a depth of about 30 inches. The depth to the depth to bedrock and droughtiness. The included areas bedrock ranges from 20 to 40 inches. In some areas the of stony soils and Rock outcrop also are limitations. The surface layer is stony. plants selected for seeding should be those that meet the Permeability is very slow in the Medco soil. Available seasonal requirements of livestock or wildlife, or both. water capacity is about 4 inches. The effective rooting This unit is limited as a site for livestock watering depth is limited by a dense layer of clay at a depth of 6 to ponds and other water impoundments because of the 18 inches. Runoff is slow, and the hazard of water erosion slope and the depth to bedrock. is slight. The water table, which is perched above the layer The vegetative site in areas of the Medco soil is Clayey of clay, is at a depth of 0.5 foot to 1.5 feet from December Hills, 20- to 35-inch precipitation zone, and the one in through March. areas of the McMullin soil is Loamy Shrub Scabland, 18- The McMullin soil is shallow and well drained. It to 35-inch precipitation zone. formed in colluvium derived dominantly from andesite, tuff, and breccia. Typically, the surface layer is dark 125F-Medco-McMullin complex, 12 to 50 percent reddish brown gravelly loam about 7 inches thick. The slopes. This map unit is on hillslopes. Elevation is 1,300 to subsoil is dark reddish brown gravelly clay loam about 10 4,000 feet. The mean annual precipitation is 20 to 35 inches thick. Bedrock is at a depth of about 17 inches. inches, the mean annual temperature is 45 to 52 degrees F, The depth to bedrock ranges from 12 to 20 inches. In and the average frost-free period is 100 to 160 days. The some areas the surface layer is stony. native vegetation on the Medco soil is mainly hardwoods Permeability is moderate in the McMullin soil. Available and an understory of grasses, shrubs, and forbs. That on water capacity is about 2 inches. The effective rooting the McMullin soil is mainly grasses, shrubs, and forbs. depth is 12 to 20 inches. Runoff is slow, and the hazard of This unit is about 50 percent Medco soil and 30 percent water erosion is slight. McMullin soil. The components of this unit occur as areas This unit is used for livestock grazing and wildlife so intricately intermingled that mapping them separately habitat. The main limitations affecting livestock grazing on was not practical at the scale used. the Medco soil are compaction, cobbles and stones on the Included in this unit are small areas of Carney and surface, and wetness in winter and spring. The main McNull soils, Rock outcrop on ridges and convex limitations in areas of the McMullin soil are compaction, the depth to bedrock, cobbles and stones slopes, and soils that are similar to the McMullin soil but in spring, grazing should be delayed until the more desirable have more than 35 percent rock fragments or have bedrock forage plants have achieved enough growth to withstand at a depth of less than 12 or more than 20 inches. Also grazing pressure and the soil is firm enough to withstand included are small areas of soils that are similar to the trampling by livestock. Compaction can be minimized by Medco soil but have bedrock at a depth of more than 40 grazing first in the areas that dry out earliest. inches, poorly drained soils near drainageways and on Suitable management practices on this unit include concave slopes, and Medco and McMullin soils that have proper grazing use, deferred grazing, rotation grazing, and slopes of less than 12 or more than 50 percent. Included brush control. Areas that support a large amount of areas make up about 20 percent of the total acreage. competing vegetation can be improved by chemical or The Medco soil is moderately deep and moderately well mechanical treatment. In places the use of ground drained. It formed in colluvium derived dominantly from equipment is limited by the seasonal wetness, the slope, andesite, tuff, and breccia. Typically, the surface layer is and the included stony soils and Rock outcrop. very dark brown and very dark grayish brown cobbly clay Range seeding is suitable on the Medco soil if the site is loam about 7 inches thick. The next layer is very dark in poor condition. The main limitations are the cobbly grayish brown cobbly clay loam about 5 inches thick. The surface layer, wetness in winter and spring, and subsoil is brown clay about 18 inches thick. Weathered droughtiness in summer and fall. The suitability of the bedrock is at a depth of about 30 inches. The depth to McMullin soil for seeding is poor. The main limitations are bedrock ranges from 20 to 40 inches. In some areas the the depth to bedrock and droughtiness. The included areas surface layer is stony. of stony soils and Rock outcrop also are limitations. The Permeability is very slow in the Medco soil. Available plants selected for seeding should be those that meet the water capacity is about 4 inches. The effective rooting depth seasonal requirements of livestock or wildlife, or both. is limited by a dense layer of clay at a depth of 6 to 18 This unit is limited as a site for livestock watering inches. Runoff is medium or rapid, and the hazard of water ponds and other water impoundments because of the erosion is moderate or high. The water table, which is slope and the depth to bedrock. perched above the layer of clay, is at a depth of 0.5 foot to The vegetative site in areas of the Medco soil is Loamy 1.5 feet from December through March. Hills, 20- to 35-inch precipitation zone, and the one in The McMullin soil is shallow and well drained. It formed areas of the McMullin soil is Loamy Shrub Scabland, 18- in colluvium derived dominantly from andesite, tuff, and to 35-inch precipitation zone. breccia. Typically, the surface layer is dark reddish brown gravelly loam about 7 inches thick. The subsoil is dark 126F-Medco-McNull complex, 12 to 50 percent reddish brown gravelly clay loam about 10 inches thick. slopes. This map unit is on hillslopes. Elevation is 1,500 to Bedrock is at a depth of about 17 inches. The depth to 4,000 feet. The mean annual precipitation is 20 to 35 inches, bedrock ranges from 12 to 20 inches. In some areas the the mean annual temperature is 45 to 52 degrees F, and the surface layer is stony. average frost-free period is 100 to 160 days. The native Permeability is moderate in the McMullin soil. Available vegetation on the Medco soil is mainly hardwoods and an water capacity is about 2 inches. The effective rooting depth understory of grasses, shrubs, and forbs. That on the is 12 to 20 inches. Runoff is medium or rapid, and the McNull soil is mainly conifers and hardwoods and an hazard of water erosion is moderate or high. understory of grasses, shrubs, and forbs. This unit is used for livestock grazing and wildlife habitat. This unit is about 55 percent Medco soil and 30 percent The main limitations affecting livestock grazing on the McNull soil. The components of this unit occur as areas so Medco soil are compaction, erosion, cobbles and stones on intricately intermingled that mapping them separately was the surface, wetness in winter and spring, droughtiness in not practical at the scale used. summer and fall, and the slope. The main limitations in Included in this unit are small areas of McMullin soils on areas of the McMullin soil are compaction, erosion, cobbles ridges and convex slopes, poorly drained soils near and stones on the surface, the depth to bedrock, drainageways, soils that are similar to the McNull and droughtiness, and the slope. The vegetation suitable for Medco soils but have bedrock at a depth of more than 40 grazing includes Idaho fescue, bluebunch wheatgrass, and inches, and soils that are similar to the Medco soil but are pine bluegrass. If the range is overgrazed, the proportion of 18 to 30 inches deep to a dense layer of clay. Also included preferred forage plants decreases and the proportion of less are small areas of McNull and Medco soils that have slopes preferred forage plants increases. of less than 12 or more than 50 Because the Medco soil remains wet for long periods percent. Included areas make up about 15 percent of the to withstand trampling by livestock. Compaction can be total acreage. minimized by grazing first in the areas that dry out earliest. The Medco soil is moderately deep and moderately well Thinning, logging, and fire reduce the density of the drained. It formed in colluvium derived dominantly from overstory canopy and increase the production of andesite, tuff, and breccia. Typically, the surface layer is understory vegetation. Areas that support a large amount very dark brown and very dark grayish brown cobbly clay of competing vegetation can be improved by prescribed loam about 7 inches thick. The next layer is very dark burning or by chemical or mechanical treatment. In places grayish brown cobbly clay loam about 5 inches thick. The the use of ground equipment is limited by the seasonal subsoil is brown clay about 18 inches thick. Weathered wetness, the slope, and the included areas of stony soils bedrock is at a depth of about 30 inches. The depth to and Rock outcrop. bedrock ranges from 20 to 40 inches. In some areas the Range seeding is suitable on the Medco soil if the site is surface layer is stony. in poor condition. The main limitations are wetness in winter Permeability is very slow in the Medco soil. Available and spring and droughtiness in summer and fall. The plants water capacity is about 4 inches. The effective rooting depth selected for seeding should be those that meet the is limited by a dense layer of clay at a depth of 6 to 18 seasonal requirements of livestock or wildlife, or both. inches. Runoff is medium or rapid, and the hazard of water Seeding disturbed areas to suitable plants increases forage erosion is moderate or high. The water table, which is production and reduces the risk of erosion. perched above the layer of clay, is at a depth of 0.5 foot to The McNull soil is suited to the production of Douglas fir 1.5 feet from December through March. and ponderosa pine. Other species that grow on this unit The McNull soil is moderately deep and well drained. It include incense cedar, California black oak, and Pacific formed in colluvium derived dominantly from andesite, tuff, madrone. The understory vegetation includes Pacific and breccia. Typically, the surface is covered with a layer of serviceberry, tall Oregongrape, and California fescue. needles, leaves, and twigs about 1 inch thick. The surface On the basis of a 100-year site curve, the mean site layer is dark reddish brown loam about 6 inches thick. The index for Douglas fir is 95 on the McNull soil. The yield at upper 6 inches of the subsoil is dark reddish brown clay culmination of the mean annual increment is 4,620 cubic loam. The lower 20 inches is dark reddish brown cobbly feet per acre in a fully stocked, even-aged stand of trees at clay. Weathered bedrock is at a depth of about 32 inches. 60 years and 37,120 board feet per acre (Scribner rule) at The depth to bedrock ranges from 20 to 40 inches. In some 160 years. On the basis of a 50-year curve, the mean site areas the surface layer is stony or cobbly. index is 70. Permeability is slow in the McNull soil. Available water The main limitations affecting timber production on the capacity is about 4 inches. The effective rooting depth is McNull soil are erosion, compaction, seedling mortality, and 20 to 40 inches. Runoff is medium, and the hazard of plant competition. Also, the bedrock restricts root growth. water erosion is moderate. As a result, windthrow is a hazard. This unit is used mainly for livestock grazing or wildlife Wheeled and tracked logging equipment can be used in habitat. The McNull soil also is used for timber production. the less sloping areas, but cable yarding generally is safer The main limitations affecting livestock grazing are in the more sloping areas and results in less surface compaction, erosion, and the slope. The Medco soil also is disturbance. Using standard wheeled and tracked limited by wetness in winter and spring. The vegetation equipment when the soil is moist causes rutting and suitable for grazing includes Idaho fescue, bluebunch compaction. Puddling can occur when the soil is wet. Using wheatgrass, and pine bluegrass on the Medco soil and low-pressure ground equipment causes less damage to the Idaho fescue, tall trisetum, and western fescue on the soil and helps to maintain productivity. Compaction can be McNull soil. If the range is overgrazed, the proportion of minimized by using suitable methods of harvesting, laying preferred forage plants decreases and the proportion of out skid trails in advance, and harvesting timber when the less preferred forage plants increases. soil is least susceptible to compaction. Ripping skid trails A planned grazing system that includes timely deferment and landings when the soil is dry can improve the growth of of grazing, rotation grazing, and proper livestock distribution plants. helps to prevent overgrazing of the understory and damage Properly designed road drainage systems that include to the soils. Because the Medco soil remains wet for long carefully located culverts help to control erosion. Areas that periods in spring, grazing should be delayed until the more have been cut and filled are easily eroded unless they are desirable forage plants have achieved enough growth to treated. Seeding, mulching, and benching these areas help withstand grazing pressure and the soil is firm enough to control erosion. Steep yarding paths, skid trails, and firebreaks are subject to soils. Also included are small areas of Medford soils that rilling and gullying unless they are protected by a plant have slopes of more than 3 percent. Included areas make cover or adequate water bars, or both. Skid trails and up about 15 percent of the total acreage. unsurfaced roads may be impassable during rainy periods. Permeability is moderately slow in the Medford soil. Logging roads require suitable surfacing for year-round Available water capacity is about 10 inches. The effective use. rooting depth is 60 inches or more. Runoff is slow, and The Medco soil, which occurs throughout the unit, is the hazard of water erosion is slight. The water table subject to severe slumping. Road failure and landslides are fluctuates between depths of 4 and 6 feet from December likely to occur after road construction and clearcutting. through April. Slumping can be minimized by constructing logging roads in This unit is used mainly for irrigated crops, such as the less sloping areas, on better suited soils if practical, and alfalfa hay, tree fruit, and small grain. Other crops include by installing properly designed road drainage systems. corn for silage and sugar beet seed. Some areas are A high temperature in the surface layer and an used for homesite development, grass-legume hay, or insufficient moisture supply in summer increase the pasture. seedling mortality rate, especially on south- and This unit is well suited to irrigated crops. It is limited southwest-facing slopes. To compensate for the expected mainly by the moderately slow permeability and wetness in high mortality rate, the larger seedlings or a greater number winter and spring. In summer, irrigation is needed for the of seedlings should be planted. When the timber is maximum production of most crops. Furrow, border, harvested, leaving some of the larger trees unharvested corrugation, trickle, and sprinkler irrigation systems are provides shade for seedlings. Reforestation can be suitable. The system used generally is governed by the crop accomplished by planting Douglas fir and ponderosa pine that is grown. For the efficient application and removal of seedlings. surface irrigation water, land leveling is needed. To prevent Undesirable plants limit natural or artificial overirrigation and excessive erosion, applications of reforestation unless intensive site preparation and irrigation water should be adjusted to the available water maintenance measures are applied. Mulching around capacity, the rate of water intake, and the needs of the crop. seedlings helps to maintain the moisture supply in The use of pipe, ditch lining, or drop structures in irrigation summer and minimizes competition from undesirable ditches reduces water loss and the hazard of erosion. understory plants. A subsurface drainage system can lower the water The vegetative site in areas of the Medco soil is Loamy table if a suitable outlet is available. Land smoothing and Hills, 20- to 35-inch precipitation zone, and the one in open ditches can reduce surface wetness. areas of the McNull soil is Pine-Douglas - Returning all crop residue to the soil and using a cropping system that includes grasses, legumes, or 127A-Medford silty clay loam, 0 to 3 percent slopes. grass-legume mixtures help to maintain fertility and tilth. This very deep, moderately well drained soil is on stream Leaving crop residue on or near the surface helps to terraces. It formed in alluvium derived dominantly from conserve moisture and control erosion. metamorphic rock. Elevation is 1,000 to 4,000 feet. The A tillage pan forms easily if the soil is tilled when wet. mean annual precipitation is 18 to 35 inches, the mean Chiseling or subsoiling breaks up the pan. Surface crusting annual temperature is 50 to 54 degrees F, and the average and compaction can be minimized by returning crop residue frost-free period is 125 to 180 days. The vegetation in to .the soil. areas that have not been cultivated is mainly grasses and Solid-set sprinkler irrigation is the best method of forbs. controlling frost and providing adequate moisture for tree Typically, the surface layer is very dark brown silty clay fruit. Compaction can be minimized by limiting the use of loam about 12 inches thick. The upper 10 inches of the equipment when the soil is wet. A permanent cover crop subsoil is very dark brown silty clay. The next 31 inches is helps to control runoff and erosion. dark brown and dark yellowish brown silty clay loam and Proper stocking rates, pasture rotation, and restricted clay loam. The lower part to a depth of 71 inches is dark grazing during wet periods help to keep pastures in good yellowish brown sandy clay loam. In some areas the surface condition and protect the soil from erosion. Grazing when layer is gravelly or cobbly. the soil is wet results in compaction of the surface layer, Included in this unit are small areas of Abin, Evans, poor tilth, and excessive runoff. Periodic mowing and Newberg, and Camas soils on flood plains; Gregory soils clipping help to maintain uniform plant growth, discourage on the lower terraces and on concave slopes; Coleman selective grazing, and reduce the extent of clumpy growth. soils on the higher terraces; and Central Point Fertilizer is needed to ensure the optimum growth of grasses and legumes. Grasses respond to nitrogen, and legumes respond to Permeability is moderately slow in the Medford soil. sulfur and phosphorus. Available water capacity is about 8 inches. The effective The main limitations affecting homesite development rooting depth is 60 inches or more. Runoff is slow, and the are the moderately slow permeability, the wetness, the hazard of water erosion is slight. The water table fluctuates shrink-swell potential, and low strength. between depths of 3 and 5 feet from December through The moderately slow permeability and depth to the April. water table increase the possibility that septic tank This unit is used mainly for irrigated crops, such as absorption fields will fail. The moderately slow permeability alfalfa hay, tree fruit, and small grain. Other crops include can be overcome by increasing the size of the absorption corn for silage and sugar beet seed. Some areas are field. Interceptor ditches can divert subsurface water and used for homesite development, grass-legume hay, or thus improve the efficiency of the absorption fields. pasture. A drainage system may be needed if roads and building This unit is well suited to irrigated crops. It is limited foundations are constructed on this unit. The wetness can mainly by the moderately slow permeability and wetness in be reduced by installing drainage tile around footings. winter and spring. In summer, irrigation is needed for the Properly designing foundations and footings, diverting maximum production of most crops. Furrow, border, runoff away from the buildings, and backfilling with material corrugation, trickle, and sprinkler irrigation systems are that has a low shrink-swell potential help to prevent the suitable. The system used generally is governed by the crop structural damage caused by shrinking and swelling. that is grown. For the efficient application and removal of Properly designing buildings and roads helps to offset the surface irrigation water, land leveling is needed. To prevent limited ability of the soil to support a load. overirrigation and excessive erosion, applications of Revegetating as soon as possible helps to control irrigation water should be adjusted to the available water erosion in disturbed areas around construction sites. capacity, the rate of water intake, and the needs of the crop. Topsoil can be stockpiled and used to reclaim areas The use of pipe, ditch lining, or drop structures in irrigation disturbed during construction. Because of a low amount of ditches reduces water loss and the hazard of erosion. rainfall in summer, irrigation is needed in areas that support A subsurface drainage system can lower the water lawn grasses, shrubs, vines, shade trees, or ornamental table if a suitable outlet is available. Land smoothing and trees. open ditches can reduce surface wetness. The vegetative site is Deep Loamy Terrace, 18- to Returning all crop residue to the soil and using a 28-inch precipitation zone. cropping system that includes grasses, legumes, or grass-legume mixtures help to maintain fertility and tilth. 128B-Medford clay loam, gravelly substratum, 0 to 7 Leaving crop residue on or near the surface helps to percent slopes. This very deep, moderately well drained conserve moisture and control erosion. soil is on stream terraces. It formed in alluvium derived A tillage pan forms easily if the soil is tilled when wet. dominantly from metamorphic rock. Elevation is 1,000 to Chiseling or subsoiling breaks up the pan. Surface crusting 4,000 feet. The mean annual precipitation is 18 to 35 and compaction can be minimized by returning crop residue inches, the mean annual temperature is 50 to 54 degrees F, to the soil. and the average frost-free period is 125 to 180 days. The Solid-set sprinkler irrigation is the best method of vegetation in areas that have not been cultivated is mainly controlling frost and providing adequate moisture for tree grasses and forbs. fruit. Compaction can be minimized by limiting the use of Typically, the surface layer is very dark gray clay loam equipment when the soil is wet. A permanent cover crop about 9 inches thick. The subsoil is very dark grayish brown helps to control runoff and erosion. clay about 31 inches thick. The substratum to a depth of 62 Proper stocking rates, pasture rotation, and restricted inches is light olive brown very gravelly clay loam. In some grazing during wet periods help to keep pastures in good areas the surface layer is gravelly or cobbly. condition and protect the soil from erosion. Grazing when Included in this unit are small areas of Abin, Evans, the soil is wet results in compaction of the surface layer, Newberg, and Camas soils on flood plains; Gregory soils on poor tilth, and excessive runoff. Periodic mowing and the lower terraces and on concave slopes; Coleman soils on clipping help to maintain uniform plant growth, discourage the higher terraces; and Central Point soils. Also included selective grazing, and reduce the extent of clumpy growth. are small areas of Medford soils that have slopes of more Fertilizer is needed to ensure the optimum growth of than 7 percent. Included areas make up about 20 percent of grasses and legumes. Grasses respond to nitrogen, and the total acreage. legumes respond to sulfur and phosphorus. The main limitations affecting homesite development are the moderately slow permeability, the wetness, the habitat. The main limitations affecting livestock grazing are shrink-swell potential, and low strength. compaction, stones on the surface, droughtiness, and the The moderately slow permeability and depth to the water depth to bedrock. The vegetation suitable for grazing table increase the possibility that septic tank absorption includes Idaho fescue, pine bluegrass, and bluebunch fields will fail. The moderately slow permeability can be wheatgrass. If the range is overgrazed, the proportion of overcome by increasing the size of the absorption field. preferred forage plants decreases and the proportion of Interceptor ditches can divert subsurface water and thus less preferred forage plants increases. Grazing should be improve the efficiency of the absorption fields. delayed until the more desirable forage plants have A drainage system may be needed if roads and building achieved enough growth to withstand grazing pressure and foundations are constructed on this unit. The wetness can the soil is firm enough to withstand trampling by livestock. be reduced by installing drainage tile around footings. Suitable management practices on this unit include Properly designing foundations and footings, diverting proper grazing use, deferred grazing, rotation grazing, and runoff away from the buildings, and backfilling with material brush control. Areas that support a large amount of that has a low shrink-swell potential help to prevent the competing vegetation can be improved by chemical or structural damage caused by shrinking and swelling. mechanical treatment. The use of ground equipment is not Properly designing buildings and roads helps to offset the practical because of the stones on the surface. limited ability of the soil to support a load. This unit is poorly suited to range seeding. The main Revegetating as soon as possible helps to control limitations are droughtiness, the stones on the surface, and erosion in disturbed areas around construction sites. the depth to bedrock. The plants selected for seeding Topsoil can be stockpiled and used to reclaim areas should be those that meet the seasonal requirements of disturbed during construction. Because of a low amount of livestock or wildlife, or both. rainfall in summer, irrigation is needed in areas that support This unit is limited as a site for livestock watering lawn grasses, shrubs, vines, shade trees, or ornamental ponds and other water impoundments because of the trees. depth to bedrock. The vegetative site is Deep Loamy Terrace, 18- to The vegetative site is Loamy Juniper Scabland, 20- to 28-inch precipitation zone. 30-inch precipitation zone.

129B-Merlin extremely stony loam, 1 to 8 percent 130E-Musty-Goolaway complex, 12 to 35 percent slopes. This shallow, well drained soil is on plateaus. It slopes. This map unit is on ridges. Elevation is 2,500 to formed in residuum derived dominantly from andesite and 4,000 feet. The mean annual precipitation is 40 to 50 tuff. Elevation is 4,000 to 4,800 feet. The mean annual inches, the mean annual temperature is 45 to 50 degrees F, precipitation is 17 to 18 inches, the mean annual and the average frost-free period is 100 to 160 days. The temperature is 43 to 45 degrees F, and the average native vegetation is mainly conifers and hardwoods and an frost-free period is less than 100 days. The native understory of grasses, shrubs, and forbs. vegetation is mainly grasses, shrubs, and forbs. This unit is about 60 percent Musty soil and 20 percent Typically, the surface layer is dark brown extremely Goolaway soil. The Goolaway soil commonly has slopes of stony loam about 11 inches thick. The subsoil is dark brown more than 20 percent. The components of this unit occur as clay about 2 inches thick. Bedrock is at a depth of about 13 areas so intricately intermingled that mapping them inches. The depth to bedrock ranges from 10 to 20 inches. separately was not practical at the scale used. In some areas the surface layer is very gravelly or very Included in this unit are small areas of Josephine, cobbly. Siskiyou, and Speaker soils; Pollard soils on concave Included in this unit are small areas of Bly and Royst slopes; Rock outcrop; soils that are similar to the Musty soil soils and soils that are similar to the Merlin soil but have but have bedrock within a depth of 20 inches; and soils that bedrock within a depth of 10 inches or have a subsoil of are similar to the Goolaway soil but have bedrock at a depth loam. Also included are small areas of Merlin soils that of more than 40 inches. Also included are small areas of have slopes of more than 8 percent. Included areas make Musty and Goolaway soils that have slopes of less than 12 up about 20 percent of the total acreage. or more than 35 percent. Included areas make up about 20 Permeability is very slow in the Merlin soil. Available percent of the total acreage. water capacity is about 2 inches. The effective rooting The Musty soil is moderately deep and well drained. It depth is 10 to 20 inches. Runoff is rapid, and the hazard of formed in colluvium derived dominantly from schist. water erosion is moderate. This unit is used for livestock grazing and wildlife Typically, the surface is covered with a layer of needles, more sloping areas and results in less surface disturbance. leaves, and twigs about 1 inch thick. The surface layer is If the soils are excessively disturbed when timber is very dark grayish brown gravelly loam about 12 inches thick. harvested or logging roads are built, a larger number of rock The subsoil is dark grayish brown very cobbly loam about fragments is left on the surface. Using standard wheeled 17 inches thick. Bedrock is at a depth of about 29 inches. and tracked equipment when the soils are moist causes The depth to bedrock ranges from 20 to 40 inches. In some rutting and compaction. Puddling can occur when the soils areas the surface layer is very gravelly, very cobbly, or are wet. Using low-pressure ground equipment causes less stony. damage to the soils and helps to maintain productivity. Permeability is moderate in the Musty soil. Available Compaction can be minimized by using suitable methods of water capacity is about 3 inches. The effective rooting harvesting, laying out skid trails in advance, and harvesting depth is 20 to 40 inches. Runoff is medium, and the timber when the soils are least susceptible to compaction. hazard of water erosion is moderate or high. Ripping skid trails and landings when the soils are dry can The Goolaway soil is moderately deep and well drained. improve the growth of plants. It formed in colluvium derived dominantly from schist. Properly designed road drainage systems that include Typically, the surface is covered with a layer of needles, carefully located culverts help to control erosion. Areas that leaves, and twigs about 2 inches thick. The surface layer is have been cut and filled are easily eroded unless they are very dark grayish brown silt loam about 3 inches thick. The treated. Seeding, mulching, and benching these areas help next layer is dark grayish brown silt loam about 8 inches to control erosion. Steep yarding paths, skid trails, and thick. The subsoil is olive gray and olive silt loam about 18 firebreaks are subject to rilling and gullying unless they are inches thick. Weathered bedrock is at a depth of about 29 protected by a plant cover or adequate water bars, or both. inches. The depth to bedrock ranges from 20 to 40 inches. Skid trails and unsurfaced roads may be impassable during Permeability is moderate in the Goolaway soil. Available rainy periods. Logging roads require suitable surfacing for water capacity is about 6 inches. The effective rooting depth year-round use. is 20 to 40 inches. Runoff is medium, and the hazard of A high temperature in the surface layer and an water erosion is moderate or high. insufficient moisture supply in summer increase the This unit is used for timber production and wildlife seedling mortality rate on south- and southwest-facing habitat. It is suited to the production of Douglas fir. Other slopes. The large number of rock fragments in the Musty species that grow on this unit include ponderosa pine, soil also increases the seedling mortality rate. To sugar pine, and incense cedar. The understory vegetation compensate for the expected high mortality rate, the larger includes golden chinkapin, cascade Oregongrape, and seedlings or a greater number of seedlings should be deerfoot vanillaleaf. planted. When the timber is harvested, leaving some of the On the basis of a 100-year site curve, the mean site larger trees unharvested provides shade for seedlings. The index for Douglas fir is 110 on the Musty soil. The yield at seedling mortality rate also can be reduced by providing culmination of the mean annual increment is 5,880 cubic artificial shade for seedlings. Reforestation can be feet per acre in a fully stocked, even-aged stand of trees at accomplished by planting Douglas fir and ponderosa pine 60 years and 48,300 board feet per acre (Scribner rule) at seedlings. 140 years. On the basis of a 50-year curve, the mean site Undesirable plants limit natural or artificial reforestation index is 80. unless intensive site preparation and maintenance On the basis of a 100-year site curve, the mean site measures are applied. Reforestation can be accomplished index for Douglas fir is 115 on the Goolaway soil. The yield by planting Douglas fir and ponderosa pine seedlings. at culmination of the mean annual increment is 6,360 cubic Mulching around seedlings helps to maintain the moisture feet per acre in a fully stocked, even-aged stand of trees at supply in summer and minimizes competition from 60 years and 45,600 board feet per acre (Scribner rule) at undesirable understory plants. 150 years. On the basis of a 50-year curve, the mean site Increased erosion, loss of plant nutrients, and water index is 95. repellency are likely to result from fires of moderate The main limitations affecting timber production are intensity. erosion, compaction, seedling mortality, and plant The vegetative site is Douglas Fir-Chinkapin Forest. competition. Also, the bedrock restricts root growth. As a result, windthrow is a hazard. 131F-Musty-Goolaway complex, 35 to 50 percent When timber is harvested, management that minimizes north slopes. This map unit is on hillslopes. Elevation is the risk of erosion is essential. Wheeled and tracked logging 2,500 to 4,000 feet. The mean annual precipitation is 40 to equipment can be used in the less sloping areas, but cable 50 inches, the mean annual temperature is 45 to yarding generally is safer in the 50 degrees F, and the average frost-free period is 100 to cubic feet per acre in a fully stocked, even-aged stand of 160 days. The native vegetation is mainly conifers and trees at 60 years and 52,440 board feet per acre (Scribner hardwoods and an understory of grasses, shrubs, and rule) at 120 years. On the basis of a 50-year curve, the forbs. mean site index is 85. This unit is about 40 percent Musty soil and 35 percent On the basis of a 100-year site curve, the mean site Goolaway soil. The components of this unit occur as index for Douglas fir is 125 on the Goolaway soil. The yield areas so intricately intermingled that mapping them at culmination of the mean annual increment is 7,320 cubic separately was not practical at the scale used. feet per acre in a fully stocked, even-aged stand of trees at Included in this unit are small areas of Josephine, 60 years and 45,600 board feet per acre (Scribner rule) at Siskiyou, and Speaker soils; Pollard soils on the less 150 years. On the basis of a 50-year curve, the mean site sloping parts of the landscape and on concave slopes; and index is 95. soils that are similar to the Musty and Goolaway soils but The main limitations affecting timber production are the have bedrock at a depth of more than 40 inches. Also slope, erosion, compaction, plant competition, and included are small areas of and Musty and Goolaway soils seedling mortality. Also, the bedrock restricts root growth. that have slopes of less than 35 or more than 50 percent. As a result, windthrow is a hazard. Included areas make up about 25 percent of the total When timber is harvested, management that minimizes acreage. the risk of erosion is essential. Wheeled and tracked The Musty soil is moderately deep and well drained. It logging equipment can be used in the less sloping areas, formed in colluvium derived dominantly from schist. but cable yarding generally is safer and results in less Typically, the surface is covered with a layer of needles, surface disturbance. If the soils are excessively disturbed leaves, and twigs about 1 inch thick. The surface layer is when timber is harvested or logging roads are built, a larger very dark grayish brown gravelly loam about 12 inches number of rock fragments is left on the surface. Using thick. The subsoil is dark grayish brown very cobbly loam standard wheeled and tracked equipment when the soils about 17 inches thick. Bedrock is at a depth of about 29 are moist causes rutting and compaction. Puddling can inches. The depth to bedrock ranges from 20 to 40 inches. occur when the soils are wet. Using low-pressure ground In some areas the surface layer is very gravelly or very equipment causes less damage to the soils and helps to cobbly. maintain productivity. Compaction can be minimized by Permeability is moderate in the Musty soil. Available using suitable methods of harvesting, laying out skid trails in water capacity is about 3 inches. The effective rooting advance, and harvesting timber when the soils are least depth is 20 to 40 inches. Runoff is rapid, and the hazard susceptible to compaction. Ripping skid trails and landings of water erosion is high. when the soils are dry can improve the growth of plants. The Goolaway soil is moderately deep and well drained. Properly designed road drainage systems that include It formed in colluvium derived dominantly from schist. carefully located culverts help to control erosion. Areas that Typically, the surface is covered with a layer of needles, have been cut and filled are easily eroded unless they are leaves, and twigs about 2 inches thick. The surface layer is treated. Seeding, mulching, and benching these areas help very dark grayish brown silt loam about 3 inches thick. The to control erosion. Steep yarding paths, skid trails, and next layer is dark grayish brown silt loam about 8 inches firebreaks are subject to rilling and gullying unless they are thick. The subsoil is olive gray and olive silt loam about 18 protected by a plant cover or adequate water bars, or both. inches thick. Weathered bedrock is at a depth of about 29 Constructing logging roads on the steeper slopes can inches. The depth to bedrock ranges from 20 to 40 inches. result in a high risk of erosion. Material that is discarded Permeability is moderate in the Goolaway soil. Available when the roads are built can damage vegetation and is a water capacity is about 6 inches. The effective rooting potential source of sedimentation. If the material becomes depth is 20 to 40 inches. Runoff is rapid, and the hazard of saturated, avalanches of debris can occur. End hauling of water erosion is high. the waste material minimizes damage to the vegetation This unit is used for timber production and wildlife downslope and reduces the risk of sedimentation. habitat. It is suited to the production of Douglas fir. Other This unit is subject to slumping. Road failure and species that grow on this unit include ponderosa pine, landslides are likely to occur after road construction and incense cedar, and sugar pine. The understory vegetation clearcutting. Slumping can be minimized by constructing includes golden chinkapin, cascade Oregongrape, and logging roads in the less sloping areas, on better suited soils deerfoot vanillaleaf. if practical, and by installing properly designed On the basis of a 100-year site curve, the mean site index for Douglas fir is 120 on the Musty soil. The yield at culmination of the mean annual increment is 6,900 road drainage systems. Skid trails and unsurfaced roads surface layer is very dark grayish brown silt loam about 3 may be impassable during rainy periods. Logging roads inches thick. The next layer is dark grayish brown silt loam require suitable surfacing for year-round use. about 8 inches thick. The subsoil is olive gray and olive silt Undesirable plants limit natural or artificial reforestation loam about 18 inches thick: Weathered bedrock is at a unless intensive site preparation and maintenance depth of about 29 inches. The depth to bedrock ranges measures are applied. Reforestation can be accomplished from 20 to 40 inches. by planting Douglas fir and ponderosa pine seedlings. Permeability is moderate in the Goolaway soil. Available Mulching around seedlings helps to maintain the moisture water capacity is about 6 inches. The effective rooting supply in summer and minimizes competition from depth is 20 to 40 inches. Runoff is rapid, and the hazard of undesirable understory plants. water erosion is high. Increased erosion, loss of plant nutrients, and water This unit is used for timber production and wildlife repellency are likely to result from fires of moderate habitat. It is suited to the production of Douglas fir. Other intensity. species that grow on this unit include ponderosa pine, The vegetative site is Douglas Fir-Chinkapin Forest. sugar pine, and California black oak. The understory vegetation includes canyon live oak, deerbrush, and 132F-Musty-Goolaway complex, 35 to 50 percent western fescue. south slopes. This map unit is on hillslopes. Elevation is On the basis of a 100-year site curve, the mean site 2,500 to 4,000 feet. The mean annual precipitation is 40 to index for Douglas fir is 110 on the Musty soil. The yield at 50 inches, the mean annual temperature is 45 to 50 culmination of the mean annual increment is 5,880 cubic degrees F, and the average frost-free period is 100 to 160 feet per acre in a fully stocked, even-aged stand of trees at days. The native vegetation is mainly conifers and 60 years and 48,300 board feet per acre (Scribner rule) at hardwoods and an understory of grasses, shrubs, and 140 years. On the basis of a 50-year curve, the mean site forbs. index is 80. This unit is about 45 percent Musty soil and 30 percent On the basis of a 100-year site curve, the mean site Goolaway soil. The components of this unit occur as areas index for Douglas fir is 115 on the Goolaway soil. The yield so intricately intermingled that mapping them separately at culmination of the mean annual increment is 6,360 cubic was not practical at the scale used. feet per acre in a fully stocked, even-aged stand of trees at Included in this unit are small areas of Josephine, 60 years and 50,700 board feet per acre (Scribner rule) at Siskiyou, and Speaker soils; Pollard soils on the less 130 years. On the basis of a 50-year curve, the mean site sloping parts of the landscape and on concave slopes; index is 90. and soils that are similar to the Musty and Goolaway soils The main limitations affecting timber production are the but have bedrock at a depth of more than 40 inches. Also slope, erosion, compaction, seedling mortality, and plant included are small areas of Musty and Goolaway soils that competition. Also, the bedrock restricts root growth. As a have slopes of less than 35 or more than 50 percent. result, windthrow is a hazard. Included areas make up about 25 percent of the total When timber is harvested, management that minimizes acreage. the risk of erosion is essential. Wheeled and tracked The Musty soil is moderately deep and well drained. It logging equipment can be used in the less sloping areas, formed in colluvium derived dominantly from schist. but cable yarding generally is safer and results in less Typically, the surface is covered with a layer of needles, surface disturbance. If the soils are excessively disturbed leaves, and twigs about 1 inch thick. The surface layer is when timber is harvested or logging roads are built, a very dark grayish brown gravelly loam about 12 inches larger number of rock fragments is left on the surface. thick. The subsoil is dark grayish brown very cobbly loam Using standard wheeled and tracked equipment when the about 17 inches thick. Bedrock is at a depth of about 29 soils are moist causes rutting and compaction. Puddling inches. The depth to bedrock ranges from 20 to 40 inches. can occur when the soils are wet. Using low-pressure In some areas the surface. layer is very gravelly or very ground equipment causes less damage to the soils and cobbly. helps to maintain productivity. Compaction can be Permeability is moderate in the Musty soil. Available minimized by using suitable methods of harvesting, laying water capacity is about 3 inches. The effective rooting out skid trails in advance, and harvesting timber when the depth is 20 to 40 inches. Runoff is rapid, and the hazard of soils are least susceptible to compaction. Ripping skid water erosion is high. trails and landings when the soils are dry can improve the The Goolaway soil is moderately deep and well growth of plants. drained. It formed in colluvium derived dominantly from Properly designed road drainage systems that include schist. Typically, the surface is covered with a layer of carefully located culverts help to control erosion. needles, leaves, and twigs about 2 inches thick. The Areas that have been cut and filled are easily eroded mainly hardwoods and an understory of grasses, unless they are treated. Seeding, mulching, and benching shrubs, and forbs. these areas help to control erosion. Steep yarding paths, Typically, the surface layer is very dark grayish brown skid trails, and firebreaks are subject to rilling and gullying fine sandy loam about 17 inches thick. The upper 13 inches unless they are protected by a plant cover or adequate of the substratum is dark brown sandy loam. The next 12 water bars, or both. inches is dark brown fine sand. The lower part to a depth of Constructing logging roads on the steeper slopes can 60 inches is dark grayish brown loamy sand. In some areas result in a high risk of erosion. Material that is discarded the surface layer is gravelly or cobbly. when the roads are built can damage vegetation and is a Included in this unit are small areas of Abin, Camas, and potential source of sedimentation. If the material becomes Evans soils; Cove soils on concave slopes; Central Point, saturated, avalanches of debris can occur. End hauling of Medford, Takilma soils on terraces; and soils that are similar the waste material minimizes damage to the vegetation to the Newberg soil but have a gravelly or very gravelly downslope and reduces the risk of sedimentation. substratum. Also included are small areas of Riverwash, This unit is subject to slumping. Road failure and poorly drained soils, and Newberg soils that have slopes of landslides are likely to occur after road construction and more than 3 percent. Included areas make up about 20 clearcutting. Slumping can be minimized by constructing percent of the total acreage. logging roads in the less sloping areas, on better suited soils Permeability is moderately rapid in the upper part of the if practical, and by installing properly designed road Newberg soil and rapid in the lower part. Available water drainage systems. Skid trails and unsurfaced roads may be capacity is about 8 inches. The effective rooting depth is 60 impassable during rainy periods. Logging roads require inches or more. The substratum can restrict the penetration suitable surfacing for year-round use. of roots, however, because of droughtiness. Runoff is slow, A high temperature in the surface layer and an and the hazard of water erosion is slight. This soil is insufficient moisture supply in summer increase the occasionally flooded for brief periods from December seedling mortality rate. The large number of rock fragments through March. in the Musty soil also increases the seedling mortality rate. This unit is used mainly for irrigated crops, such as To compensate for the expected high mortality rate, the alfalfa hay and small grain. Other crops include corn for larger seedlings or a greater number of seedlings should be silage. Some areas are used for grass-legume hay, planted. When the timber is harvested, leaving some of the pasture, or homesite development. larger trees unharvested provides shade for seedlings. The This unit is suited to irrigated crops. It is limited seedling mortality rate also can be reduced by providing mainly by the hazard of flooding. This hazard can be artificial shade for seedlings. Reforestation can be reduced by levees, dikes, and diversions. accomplished by planting Douglas fir and ponderosa pine In summer, irrigation is needed for the maximum seedlings. production of most crops. Furrow, border, corrugation, Undesirable plants limit natural or artificial trickle, and sprinkler irrigation systems are suitable. The reforestation unless intensive site preparation and system used generally is governed by the crop that is maintenance measures are applied. Mulching around grown. For the efficient application and removal of surface seedlings helps to maintain the moisture supply in irrigation water, leveling is needed in the more sloping summer and minimizes competition from undesirable areas. To prevent overirrigation and the leaching of plant understory plants. nutrients, applications of irrigation water should be adjusted Increased erosion, loss of plant nutrients, and water to the available water capacity, the rate of water intake, and repellency are likely to result from fires of moderate the needs of the crop. Because the soil is droughty, the intensity. applications should be light and frequent. The use of pipe, The vegetative site is Douglas Fir-Black Oak Forest. ditch lining, or drop structures in irrigation ditches facilitates irrigation and reduces the hazard of ditch erosion. 133A-Newberg fine sandy loam, 0 to 3 percent Returning all crop residue to the soil and using a slopes. This very deep, somewhat excessively drained soil cropping system that includes grasses, legumes, or is on flood plains. It formed in alluvium derived from mixed grass-legume mixtures help to maintain fertility and tilth. sources. Elevation is 1,000 to 3,000 feet. The mean annual Leaving crop residue on or near the surface helps to precipitation is 18 to 40 inches, the mean annual conserve moisture and control erosion. temperature is 50 to 54 degrees F, and the average A tillage pan forms easily if the soil is tilled when wet. frost-free period is 150 to 180 days. The vegetation in areas Chiseling or subsoiling breaks up the pan. Surface that have not been cultivated is crusting and compaction can be minimized by returning to 160 days. The native vegetation is mainly conifers and crop residue to the soil. hardwoods and an understory of grasses, shrubs, and Maintaining a protective plant cover in winter reduces the forbs. soil loss resulting from flooding. Proper stocking rates, This unit is about 45 percent Norling soil and 35 pasture rotation, and restricted grazing during wet periods percent Acker soil. The components of this unit occur as help to keep pastures in good condition and protect the soil areas so intricately intermingled that mapping them from erosion. Grazing when the soil is wet results in separately was not practical at the scale used. compaction of the surface layer, poor tilth, and excessive Included in this unit are small areas of Dubakella, runoff. Periodic mowing and clipping help to maintain Gravecreek, and Pearsoll soils; Dumont soils on the less uniform plant growth, discourage selective grazing, and sloping parts of the landscape and on concave slopes; and reduce the extent of clumpy growth. Fertilizer is needed to Atring and Kanid soils on the more sloping parts of the ensure the optimum growth of grasses and legumes. landscape and on convex slopes. Also included are small Grasses respond to nitrogen, and legumes respond to sulfur areas of Acker and Norling soils that have slopes of less and phosphorus. than 35 or more than 55 percent. Included areas make up The main limitations affecting homesite development about 20 percent of the total acreage. are the flooding and the rapid permeability in the The Norling soil is moderately deep and well drained. It substratum. formed in colluvium derived dominantly from metamorphic This unit is poorly suited to standard systems of waste rock. Typically, the surface is covered with a layer of disposal because of a poor filtering capacity in the needles, leaves, and twigs about 2 inches thick. The surface substratum and the hazard of flooding. Alternative waste layer is brown very gravelly loam about 5 inches thick. The disposal systems may function properly on this unit. next layer is brown gravelly clay loam about 5 inches thick. Suitable included soils are throughout the unit. Onsite The upper 12 inches of the subsoil is yellowish brown investigation is needed to locate such soils. Dikes and gravelly clay loam. The lower 7 inches is yellowish brown channels that have outlets for floodwater can protect very cobbly clay loam. Weathered bedrock is at a depth of buildings and onsite sewage disposal systems from about 29 inches. The depth to bedrock ranges from 20 to 40 flooding. inches. In some areas the surface layer is stony. In some areas excavation for houses and access roads Permeability is moderate in the Norling soil. Available exposes material that is highly susceptible to soil blowing. water capacity is about 4 inches. The effective rooting depth Revegetating as soon as possible in disturbed areas around is 20 to 40 inches. Runoff is rapid, and the hazard of water construction sites helps to control soil blowing. Cutbanks erosion is high. are not stable and are subject to slumping. To keep The Acker soil is very deep and well drained. It formed in cutbanks from caving in, excavations may require special colluvium derived dominantly from metamorphic rock. retainer walls. Typically, the surface is covered with a layer of needles, Establishing plants is difficult in areas where the surface leaves, and twigs about 4 inches thick. The surface layer is layer has been removed. Mulching and applying fertilizer brown gravelly loam about 8 inches thick. The next layer is help to establish plants in cut areas. Topsoil can be yellowish brown gravelly clay loam about 9 inches thick. The stockpiled and used to reclaim areas disturbed during upper 11 inches of the subsoil is yellowish red gravelly clay construction. In many areas it may be necessary to haul in loam. The lower 32 inches is strong brown gravelly clay topsoil for lawns and gardens. Because of droughtiness and loam. The depth to bedrock is 60 inches or more. In some a low amount of rainfall in summer, irrigation is needed in areas the surface layer is stony. areas that support lawn grasses, shrubs, vines, shade Permeability is moderately slow in the Acker soil. trees, or ornamental trees. Available water capacity is about 7 inches. The effective Roads and streets should be constructed above the rooting depth is 60 inches or more. Runoff is rapid, and the expected level of flooding. The risk of flooding has been hazard of water erosion is high. reduced in some areas by the construction of large dams This unit is used for timber production and wildlife and reservoirs upstream. habitat. It is suited to the production of Douglas fir. Other The vegetative site is Loamy Flood Plain, 18- to 30- species that grow on this unit include incense cedar, sugar inch precipitation zone. pine, and Pacific madrone. The understory vegetation includes golden chinkapin, Whipplevine, and cascade 134F-Norling-Acker complex, 35 to 55 percent south Oregongrape. slopes. This map unit is on hillslopes. Elevation is 2,400 to On the basis of a 100-year site curve, the mean site 4,000 feet. The mean annual precipitation is 45 to 60 inches, the mean annual temperature is 45 to 50 degrees F, and the average frost-free period is 100 index for Douglas fir is 125 on the Norling soil. The yield at unharvested provides shade for seedlings. The seedling culmination of the mean annual increment is 7,320 cubic mortality rate also can be reduced by providing artificial feet per acre in a fully stocked, even-aged stand of trees at shade for seedlings. Reforestation can be accomplished by 60 years and 58,200 board feet per acre (Scribner rule) at planting Douglas fir and ponderosa pine seedlings. 120 years. On the basis of a 50-year curve, the mean site Undesirable plants limit natural or artificial index is 90. reforestation unless intensive site preparation and On the basis of a 100-year site curve, the mean site maintenance measures are applied. Mulching around index for Douglas fir is 130 on the Acker soil. The yield at seedlings helps to maintain the moisture supply in culmination of the mean annual increment is 7,740 cubic summer and minimizes competition from undesirable feet per acre in a fully stocked, even-aged stand of trees at plants. 60 years and 58,520 board feet per acre (Scribner rule) at The vegetative site is Douglas Fir-Madrone- 110 years. On the basis of a 50-year curve, the mean site Chinkapin Forest. index is 95. The main limitations affecting timber production are the 135E-Oatman cobbly loam, 12 to 35 percent north slope, erosion, compaction, seedling mortality, and plant slopes. This very deep, well drained soil is on hillslopes. It competition. Also, the bedrock restricts root growth. As a formed in colluvium derived from andesite and volcanic ash. result, windthrow is a hazard. Elevation is 4,800 to 6,500 feet. The mean annual Wheeled and tracked logging equipment can be used in precipitation is 30 to 40 inches, the mean annual the less sloping areas, but cable yarding generally is safer temperature is 40 to 44 degrees F, and the average and results in less surface disturbance. Using standard frost-free period is less than 100 days. The native wheeled and tracked equipment when the soils are moist vegetation is mainly conifers and an understory of grasses, causes rutting and compaction. Puddling can occur when shrubs, and forbs. the soils are wet. Using low-pressure ground equipment Typically, the surface is covered with a layer of needles causes less damage to the soils and helps to maintain and twigs about 3 inches thick. The surface layer is dark productivity. Compaction can be minimized by using brown cobbly loam about 16 inches thick. The subsoil is suitable methods of harvesting, laying out skid trails in dark brown very cobbly sandy loam about 14 inches thick. advance, and harvesting timber when the soils are least The substratum to a depth of 60 inches also is dark brown susceptible to compaction. Ripping skid trails and landings very cobbly sandy loam. The depth to bedrock is 60 inches when the soils are dry can improve the growth of plants. or more. In some areas the surface layer is very cobbly or Properly designed road drainage systems that include stony. carefully located culverts help to control erosion. Seeding, Included in this unit are small areas of Rock outcrop and mulching, and benching areas that have been cut and filled Rubble land on ridges and convex slopes, Otwin soils on also help to control erosion. Steep yarding paths, skid trails, ridges and on the more sloping parts of the landscape, soils and firebreaks are subject to rilling and gullying unless they that are similar to the Oatman soil but have bedrock at a are protected by a plant cover or adequate water bars, or depth of 40 to 60 inches or have less than 35 percent rock both. Cutbanks occasionally slump when the soils are fragments, and poorly drained soils near drainageways and saturated. on concave slopes. Also included are small areas of Constructing logging roads on the steeper slopes can Oatman soils that have slopes of less than 12 or more than result in a high risk of erosion. Material that is discarded 35 percent. Included areas make up about 15 percent of the when the roads are built can damage vegetation and is a total acreage. potential source of sedimentation. If the material becomes Permeability is moderate in the Oatman soil. Available saturated, avalanches of debris can occur. End hauling of water capacity is about 6 inches. The effective rooting depth the waste material minimizes damage to the vegetation is 60 inches or more. Runoff is medium, and the hazard of downslope and reduces the risk of sedimentation. Skid trails water erosion is moderate. and unsurfaced roads may be impassable during rainy This unit is used for timber production, livestock periods. Logging roads require suitable surfacing for grazing, and wildlife habitat. year-round use. This unit is suited to the production of white fir and A high temperature in the surface layer and an Shasta red fir. Other species that grow on this unit include insufficient moisture supply in summer increase the western white pine, Douglas fir, and ponderosa pine. The seedling mortality rate. To compensate for the expected understory vegetation includes sierra chinkapin, western high mortality rate, the larger seedlings or a greater number princes pine, big huckleberry, and sedge. of seedlings should be planted. When the timber is On the basis of a 50-year site curve, the mean site harvested, leaving some of the larger trees index for white fir is 75. The yield at culmination of the decreases and the proportion of less preferred forage mean annual increment is 12,530 cubic feet per acre in a plants increases. fully stocked, even-aged stand of trees at 70 years. A planned grazing system that includes timely deferment On the basis of a 100-year site curve, the mean site of grazing, rotation grazing, and proper livestock distribution index for Shasta red fir is 60. The yield at culmination of the helps to prevent overgrazing of the understory and damage mean annual increment is 29,960 cubic feet per acre in a to the soil. Grazing should be delayed until the more fully stocked, even-aged stand of trees at 140 years. desirable forage plants have achieved enough growth to The main limitations affecting timber production are withstand grazing pressure and the soil is firm enough to erosion, compaction, plant competition, and seedling withstand trampling by livestock. mortality. Wheeled and tracked logging equipment can be Thinning, logging, and fire reduce the density of the used in the less sloping areas, but cable yarding generally overstory canopy and increase the production of is safer in the more sloping areas and results in less surface understory vegetation. Areas that support a large amount disturbance. If the soil is excessively disturbed when timber of competing vegetation can be improved by prescribed is harvested or logging roads are built, a larger number of burning or by chemical or mechanical treatment. Seeding rock fragments is left on the surface. Using standard disturbed areas to suitable plants increases forage wheeled and tracked equipment when the soil is moist production and reduces the risk of erosion. The seedling causes rutting and compaction. Puddling can occur when survival rate may be low, however, because of cold the soil is wet. Using low-pressure ground equipment temperatures in spring. causes less damage to the soil and helps to maintain The vegetative site is Shasta Fir-White Pine-Princes productivity. Compaction can be minimized by using Pine Forest. suitable methods of harvesting, laying out skid trails in advance, and harvesting timber when the soil is least 135G-Oatman cobbly loam, 35 to 65 percent north susceptible to compaction. Ripping skid trails and landings slopes. This very deep, well drained soil is on hillslopes. It when the soil is dry can improve the growth of plants. formed in colluvium derived from andesite and volcanic Properly designed road drainage systems that include ash. Elevation is 4,800 to 6,500 feet. The mean annual carefully located culverts help to control erosion. Seeding, precipitation is 30 to 40 inches, the mean annual mulching, and benching areas that have been cut and filled temperature is 40 to 44 degrees F, and the average also help to control erosion. Steep yarding paths, skid trails, frost-free period is less than 100 days. The native and firebreaks are subject to rilling and gullying unless they vegetation is mainly conifers and an understory of grasses, are protected by a plant cover or adequate water bars, or shrubs, and forbs. both. Skid trails and unsurfaced roads may be impassable Typically, the surface is covered with a layer of needles during rainy periods. Logging roads require suitable and twigs about 3 inches thick. The surface layer is dark surfacing for year-round use. brown cobbly loam about 16 inches thick. The subsoil is Undesirable plants limit natural or .artificial dark brown very cobbly sandy loam about 14 inches thick. reforestation unless intensive site preparation and The substratum to a depth of 60 inches also is dark brown maintenance measures are applied. Reforestation can be very cobbly sandy loam. The depth to bedrock is 60 inches accomplished by planting ponderosa pine, Shasta red fir, or more. In some areas the surface layer is very cobbly or or lodgepole pine seedlings. Mulching around seedlings stony. helps to maintain the moisture supply in summer and Included in this unit are small areas of Rock outcrop, minimizes competition from undesirable plants. Rubble land, and Otwin soils on ridges and convex slopes. Severe frost can damage or kill seedlings. In the less Also included are small areas of soils that are similar to the sloping areas where air drainage may be restricted, proper Oatman soil but have bedrock at a depth of 40 to 60 inches timber harvesting methods can reduce the effect of frost on or have less than 35 percent rock fragments and Oatman regeneration. soils that have slopes of less than 35 or more than 65 The main limitations affecting livestock grazing are percent. Included areas make up about 15 percent of the compaction and erosion. The native vegetation suitable for total acreage. grazing includes sedge, mountain brome, tall trisetum, and Permeability is moderate in the Oatman soil. Available western fescue. If the understory is overgrazed, the water capacity is about 6 inches. The effective rooting depth proportion of preferred forage plants is 60 inches or more. Runoff is rapid, and the hazard of water erosion is high. This unit is used for timber production, livestock grazing, and wildlife habitat. This unit is suited to the production of white fir and Shasta red fir. Other species that grow on this unit include maintenance measures are applied. Reforestation can be western white pine, Douglas fir, and ponderosa pine. The accomplished by planting ponderosa pine, Shasta red fir, understory vegetation includes sierra chinkapin, western or lodgepole pine seedlings. Mulching around seedlings princes pine, big huckleberry, and sedge. helps to maintain the moisture supply in summer and On the basis of a 50-year site curve, the mean site minimizes competition from undesirable plants. index for white fir is 75. The yield at culmination of the Severe frost can damage or kill seedlings. Proper timber mean annual increment is 12,530 cubic feet per acre in a harvesting methods can reduce the effect of frost on fully stocked, even-aged stand of trees at 70 years. regeneration. On the basis of a 100-year site curve, the mean site The main limitations affecting livestock grazing are index for Shasta red fir is 60. The yield at culmination of the erosion, compaction, and the slope. The native vegetation mean annual increment is 29,960 cubic feet per acre in a suitable for grazing includes sedge, mountain brome, tall fully stocked, even-aged stand of trees at 140 years. trisetum, and western fescue. If the understory is The main limitations affecting timber production are the overgrazed, the proportion of preferred forage plants slope, erosion, compaction, plant competition, and seedling decreases and the proportion of less preferred forage plants mortality. Wheeled and tracked logging equipment can be increases. used in the less sloping areas, but cable yarding generally A planned grazing system that includes timely deferment is safer and results in less surface disturbance. If the soil is of grazing, rotation grazing, and proper livestock distribution excessively disturbed when timber is harvested or logging helps to prevent overgrazing of the understory and damage roads are built, a larger number of rock fragments is left on to the soil. Grazing should be delayed until the more the surface. Using standard wheeled and tracked desirable forage plants have achieved enough growth to equipment when the soil is moist causes rutting and withstand grazing pressure and the soil is firm enough to compaction. Puddling can occur when the soil is wet. Using withstand trampling by livestock. low-pressure ground equipment causes less damage to the Thinning, logging, and fire reduce the density of the soil and helps to maintain productivity. Compaction can be overstory canopy and increase the production of minimized by using suitable methods of harvesting, laying understory vegetation. Areas that support a large amount out skid trails in advance; and harvesting timber when the of competing vegetation can be improved by prescribed soil is least susceptible to compaction. Ripping skid trails burning or by chemical or mechanical treatment. Seeding and landings when the soil is dry can improve the growth of disturbed areas to suitable plants increases forage plants. production and reduces the risk of erosion. The seedling Properly designed road drainage systems that include survival rate may be low, however, because of cold carefully located culverts help to control erosion. Seeding, temperatures in spring. mulching, and benching areas that have been cut and filled The vegetative site is Shasta Fir-White Pine-Princes also help to control erosion. Steep yarding paths, skid trails, Pine Forest. and firebreaks are subject to rilling and gullying unless they are protected by a plant cover or adequate water bars, or 136E-Oatman cobbly loam, 12 to 35 percent south both. Cutbanks occasionally slump when the soil is slopes. This very deep, well drained soil is on hillslopes. It saturated. formed in colluvium derived from andesite and volcanic Constructing logging roads on the steeper slopes can ash. Elevation is 4,800 to 6,500 feet. The mean annual result in a high risk of erosion. Building the roads at precipitation is 30 to 40 inches, the mean annual midslope requires extensive cutting and filling and removes temperature is 40 to 44 degrees F, and the average land from production. Material that is discarded when the frost-free period is less than 100 days. The native roads are built can damage vegetation and is a potential vegetation is mainly conifers and an understory of grasses, source of sedimentation. If the material becomes saturated, shrubs, and forbs. avalanches of debris can occur. End hauling of the waste Typically, the surface is covered with a layer of needles material minimizes damage to the vegetation downslope and twigs about 3 inches thick. The surface layer is dark and reduces the risk of sedimentation. Skid trails and brown cobbly loam about 16 inches thick. The subsoil is unsurfaced roads may be impassable during rainy periods. dark brown very cobbly sandy loam about 14 inches thick. Logging roads require suitable surfacing for year-round use. The substratum to a depth of 60 inches also is dark brown Undesirable plants limit natural or artificial very cobbly sandy loam. The depth to bedrock is 60 inches reforestation unless intensive site preparation and or more. In some areas the surface layer is very cobbly or stony. Included in this unit are small areas of Rock outcrop and Rubble land on ridges and convex slopes, Otwin soils or adequate water bars, or both. Skid trails and on ridges and on the more sloping parts of the landscape, unsurfaced roads may be impassable during rainy and soils that are similar to the Oatman soil but have periods. Logging roads require suitable surfacing for bedrock at a depth of 40 to 60 inches or have less than 35 year-round use. percent rock fragments. Also included are small areas of A high temperature in the surface layer during summer poorly drained soils near drainageways and on concave and the low available water capacity increase the seedling slopes and Oatman soils that have slopes of less than 12 mortality rate. The large number of rock fragments in the or more than 35 percent. Included areas make up about 15 soil also increases the seedling mortality rate. To percent of the total acreage. compensate for the expected high mortality rate, the larger Permeability is moderate in the Oatman soil. Available seedlings or a greater number of seedlings should be water capacity is about 6 inches. The effective rooting depth planted. When the timber is harvested, leaving some of the is 60 inches or more. Runoff is medium, and the hazard of larger trees unharvested provides shade for seedlings. water erosion is moderate. Reforestation can be accomplished by planting ponderosa This unit is used for timber production, livestock pine seedlings. grazing, and wildlife habitat. Severe frost can damage or kill seedlings. In the less This unit is suited to the production of white fir and sloping areas where air drainage may be restricted, proper Shasta red fir. Other species that grow on this unit include timber harvesting methods can reduce the effect of frost on western white pine, Douglas fir, and ponderosa pine. The regeneration. understory vegetation includes sierra chinkapin, western Undesirable plants limit natural or artificial princes pine, and sedge. reforestation unless intensive site preparation and On the basis of a 50-year site curve, the mean site index maintenance measures are applied. Mulching around for white fir is 75. The yield at culmination of the mean seedlings helps to maintain the moisture supply in annual increment is 12,530 cubic feet per acre in a fully summer and minimizes competition from undesirable stocked, even-aged stand of trees at 70 years. plants. On the basis of a 100-year site curve, the mean site The main limitations affecting livestock grazing are index for Shasta red fir is 55. The yield at culmination of the erosion, compaction, and the slope. The native vegetation mean annual increment is 26,880 cubic feet per acre in a suitable for grazing includes sedge, mountain brome, fully stocked, even-aged stand of trees at 140 years. Alaska oniongrass, and western fescue. If the understory is The main limitations affecting timber production are overgrazed, the proportion of preferred forage plants erosion, compaction, seedling mortality, and plant decreases and the proportion of less preferred forage competition. Wheeled and tracked logging equipment can plants increases. be used in the less sloping areas, but cable yarding A planned grazing system that includes timely deferment generally is safer in the more sloping areas and results in of grazing, rotation grazing, and proper livestock distribution less surface disturbance. If the soil is excessively disturbed helps to prevent overgrazing of the understory and damage when timber is harvested or logging roads are built, a larger to the soil. Grazing should be delayed until the more number of rock fragments is left on the surface. Using desirable forage plants have achieved enough growth to standard wheeled and tracked equipment when the soil is withstand grazing pressure and the soil is firm enough to moist causes rutting and compaction. Puddling can occur withstand trampling by livestock. when the soil is wet. Using low-pressure ground equipment Thinning, logging, and fire reduce the density of the causes less damage to the soil and helps to maintain overstory canopy and increase the production of productivity. Compaction can be minimized by using suitable understory vegetation. Areas that support a large amount methods of harvesting, laying out skid trails in advance, and of competing vegetation can be improved by prescribed harvesting timber when the soil is least susceptible to burning or by chemical or mechanical treatment. Seeding compaction. Ripping skid trails and landings when the soil is disturbed areas to suitable plants increases forage dry can improve the growth of plants. production and reduces the risk of erosion. The seedling Properly designed road drainage systems that include survival rate may be low, however, because of cold carefully located culverts help to control erosion. Seeding, temperatures in spring. mulching, and benching areas that have been cut and filled The vegetative site is White Fir-Shasta Fir Forest. also help to control erosion. Steep yarding paths, skid trails, and firebreaks are subject to rilling and gullying unless they 137C-Oatman cobbly loam, depressional, 0 to 12 are protected by a plant cover percent slopes. This very deep, well drained soil is on plateaus. It formed in colluvium and residuum derived from andesite and volcanic ash. Elevation is 4,900 to 5,200 feet. The mean annual precipitation is 30 to 40 areas that have been cut and filled also help to control inches, the mean annual temperature is 40 to 44 degrees erosion. Skid trails and unsurfaced roads may be F, and the average frost-free period is less than 100 days. impassable during rainy periods. Logging roads require The native vegetation is mainly conifers and an understory suitable surfacing for year-round use. of grasses, shrubs, and forbs. Severe frost can damage or kill seedlings. Air Typically, the surface is covered with a layer of needles drainage is restricted on this unit. Proper timber and twigs about 3 inches thick. The surface layer is dark harvesting methods can reduce the effect of frost on brown cobbly loam about 16 inches thick. The subsoil is regeneration. Reforestation can be accomplished by dark brown very cobbly sandy loam about 14 inches thick. planting seedlings of frost-tolerant species, such as The substratum to a depth of 60 inches also is dark brown ponderosa pine, Shasta red fir, and lodgepole pine. very cobbly sandy loam. The depth to bedrock is 60 inches Undesirable plants limit natural or artificial or more. In some areas the surface layer is very cobbly or reforestation unless intensive site preparation and stony. maintenance measures are applied. Mulching around Included in this unit are small areas of Rock outcrop, seedlings helps to maintain the moisture supply in Otwin and Hoxie soils, and soils that are similar to the summer and minimizes competition from undesirable Oatman soil but have bedrock at a depth of 40 to 60 inches plants. or have less than 35 percent rock fragments. Also included The main limitation affecting livestock grazing is are small areas of Oatman soils that have slopes of more compaction. The native vegetation suitable for grazing than 12 percent. Included areas make up about 10 percent includes sedge, mountain brome, western fescue, and tall of the total acreage. trisetum. If the understory is overgrazed, the proportion of Permeability is moderate in the Oatman soil. Available preferred forage plants decreases and the proportion of water capacity is about 6 inches. The effective rooting depth less preferred forage plants increases. is 60 inches or more. Runoff is slow, and the hazard of water A planned grazing system that includes timely deferment erosion is slight. of grazing, rotation grazing, and proper livestock distribution This unit is used for timber production, livestock helps to prevent overgrazing of the understory and damage grazing, and wildlife habitat. to the soil. Grazing should be delayed until the more This unit is suited to the production of white fir and desirable forage plants have achieved enough growth to lodgepole pine. Other species that grow on this unit include withstand grazing pressure and the soil is firm enough to ponderosa pine, western white pine, and Douglas fir. The withstand trampling by livestock. understory vegetation includes one-sided wintergreen, Thinning, logging, and fire reduce the density of the western princes pine, and sedge. overstory canopy and increase the production of On the basis of a 50-year site curve, the mean site index understory vegetation. Areas that support a large amount for white fir is 70. The yield at culmination of the mean of competing vegetation can be improved by prescribed annual increment is 11,410 cubic feet per acre in a fully burning or by chemical or mechanical treatment. Seeding stocked, even-aged stand of trees at 70 years. disturbed areas to suitable plants increases forage The main limitations affecting timber production are production and reduces the risk of erosion. The seedling compaction, erosion, seedling mortality, and plant survival rate may be low, however, because of cold competition. Conventional methods of harvesting timber temperatures in spring. generally are suitable, but the soil may be compacted if it is The vegetative site is White Fir-White Pine Forest. moist when heavy equipment is used. Puddling can occur when the soil is wet. If the soil is excessively disturbed when 138C-Oatman-Otwin complex, 0 to 12 percent slopes. timber is harvested or logging roads are built, a larger This map unit is on plateaus. Elevation is 4,800 to 6,500 number of rock fragments is left on the surface. Using feet. The mean annual precipitation is 30 to 40 inches, the low-pressure ground equipment causes less damage to the mean annual temperature is 40 to 44 degrees F, and the soil and helps to maintain productivity. Compaction can be average frost-free period is less than 100 days. The native minimized by using suitable methods of harvesting, laying vegetation is mainly conifers and an understory of grasses, out skid trails in advance, and harvesting timber when the shrubs, and forbs. soil is least susceptible to compaction. Ripping skid trails This unit is about 70 percent Oatman soil and 20 and landings when the soil is dry can improve the growth of percent Otwin soil. The components of this unit occur as plants. areas so intricately intermingled that mapping them Erosion can be controlled by carefully planning the separately was not practical at the scale used. construction and maintenance of logging roads, skid Included in this unit are small areas of Rock outcrop, trails, and landings. Seeding, mulching, and benching Klamath soils near drainageways and on concave slopes, soils that are similar to the Otwin soil but have 23,940 cubic feet per acre in a fully stocked, even-aged bedrock at a depth of 40 to 60 inches, and soils that are stand of trees at 140 years. similar to the Oatman soil but have less than 35 percent On the basis of a 50-year site curve, the mean site rock fragments. Also included are small areas of Oatman index for white fir is 65 on the Otwin soil. The yield at and Otwin soils that have slopes of more than 12 percent. culmination of the mean annual increment is 10,150 cubic Included areas make up about 10 percent of the total feet per acre in a fully stocked, even-aged stand of trees acreage. at 70 years. The Oatman soil is very deep and well drained. It formed On the basis of a 100-year site curve, the mean site in colluvium and residuum derived dominantly from andesite index for Shasta red fir is 40 on the Otwin soil. The yield at and volcanic ash. Typically, the surface is covered with a culmination of the mean annual increment is 18,900 cubic layer of needles and twigs about 3 inches thick. The surface feet per acre in a fully stocked, even-aged stand of trees at layer is dark brown cobbly loam about 16 inches thick. The 140 years. subsoil is dark brown very cobbly sandy loam about 14 The main limitations affecting timber production are inches thick. The substratum to a depth of 60 inches also is compaction, erosion, seedling mortality, and plant dark brown very cobbly sandy loam. The depth to bedrock is competition. Also, the bedrock restricts root growth. As a 60 inches or more. In some areas the surface layer is very result, windthrow is a hazard. cobbly or stony. Conventional methods of harvesting timber generally are Permeability is moderate in the Oatman soil. Available suitable, but the soils may be compacted if they are moist water capacity is about 6 inches. The effective rooting depth when heavy equipment is used. Puddling can occur when is 60 inches or more. Runoff is slow, and the hazard of the soils are wet. If the soils are excessively disturbed when water erosion is slight. timber is harvested or logging roads are built, a larger The Otwin soil is moderately deep and well drained. It number of rock fragments is left on the surface. Using formed in colluvium and residuum derived dominantly from low-pressure ground equipment causes less damage to the andesite and volcanic ash. Typically, the surface is covered soils and helps to maintain productivity. Compaction can be with a layer of needles and twigs about 1 inch thick. The minimized by using suitable methods of harvesting, laying surface layer is very dark grayish brown stony sandy loam out skid trails in advance, and harvesting timber when the about 3 inches thick. The next layer is dark yellowish brown soils are least susceptible to compaction. Ripping skid trails very cobbly sandy loam about 10 inches thick, The subsoil and landings when the soils are dry can improve the growth is dark brown very cobbly sandy loam about 15 inches thick. of plants. Bedrock is at a depth of about 28 inches. The depth to Erosion can be controlled by carefully planning the bedrock ranges from 20 to 40 inches. construction and maintenance of logging roads, skid trails, Permeability is moderately rapid in the Otwin soil. and landings. Seeding, mulching, and benching areas that Available water capacity is about 4 inches. The effective have been cut and filled also help to control erosion. Skid rooting depth is 20 to 40 inches. Runoff is slow, and the trails and unsurfaced roads may be impassable during hazard of water erosion is slight. rainy periods. Logging roads require suitable surfacing for This unit is used for timber production, livestock year-round use. grazing, and wildlife habitat. Severe frost can damage or kill seedlings. Air This unit is suited to the production of white fir and drainage is restricted on this unit. Proper timber Shasta red fir. Other species that grow on this unit include harvesting methods can reduce the effect of frost on western white pine, Douglas fir, and ponderosa pine. The regeneration. Reforestation can be accomplished by understory vegetation includes sierra chinkapin, western planting seedlings of frost-tolerant species, such as princes pine, big huckleberry, and sedge. ponderosa pine, Shasta red fir, and lodgepole pine. On the basis of a 50-year site curve, the mean site index Undesirable plants limit natural or artificial for white fir is 75 on the Oatman soil. The yield at reforestation unless intensive site preparation and culmination of the mean annual increment is 12,530 cubic maintenance measures are applied. Mulching around feet per acre in a fully stocked, even-aged stand of trees at seedlings helps to maintain the moisture supply in 70 years. summer and minimizes competition from undesirable On the basis of a 100-year site curve, the mean site plants. index for Shasta red fir is 50 on the Oatman soil. The yield The main limitation affecting livestock grazing is at culmination of the mean annual increment is compaction. The native vegetation suitable for grazing includes sedge, mountain brome, tall trisetum, and western fescue. If the understory is overgrazed, the proportion of preferred forage plants decreases and the proportion of less preferred forage plants increases. drainage can be grown if a properly designed drainage A planned grazing system that includes timely deferment system is installed. The ability of tile drains to remove of grazing, rotation grazing, and proper livestock distribution subsurface water from the soil is limited because of the helps to prevent overgrazing of the understory and damage very slow permeability. to the soils. Grazing should be delayed until the more In summer, irrigation is needed for the maximum desirable forage plants have achieved enough growth to production of most forage crops. Sprinkler irrigation is the withstand grazing pressure and the soils are firm enough to best method of applying water. Border and contour flood withstand trampling by livestock. irrigation systems also are suitable. For the efficient Thinning, logging, and fire reduce the density of the application and removal of surface irrigation water, land overstory canopy and increase the production of leveling is needed. Because of the very slow permeability understory vegetation. Areas that support a large amount and the water table, water applications should be regulated of competing vegetation can be improved by prescribed so that the water does not stand on the surface and burning or by chemical or mechanical treatment. Seeding damage the crop. Land smoothing and open ditches can disturbed areas to suitable plants increases forage reduce surface wetness. The use of pipe, ditch lining, or production and reduces the risk of erosion. The seedling drop structures in irrigation ditches reduces water loss and survival rate may be low, however, because of cold the hazard of erosion. temperatures in spring. Wetness limits the choice of suitable forage plants and The vegetative site is Shasta Fir-White Pine-Princes the period of cutting or grazing and increases the risk of Pine Forest. winterkill. The high content of clay severely limits tillage and root growth. Deep cracks form as the soil dries in summer. 139A-Padigan clay, 0 to 3 percent slopes. This very Proper stocking rates, pasture rotation, and restricted deep, poorly drained soil is in basins. It formed in alluvium grazing during wet periods help to keep pastures in good derived dominantly from tuff and breccia. Elevation is condition and protect the soil from erosion. Grazing when 1,200 to 3,500 feet. The mean annual precipitation is 18 to the soil is wet results in compaction of the surface layer, 30 inches, the mean annual temperature is 46 to 54 poor tilth, and excessive runoff. Periodic mowing and degrees F, and the average frost-free period is 120 to 180 clipping help to maintain uniform plant growth, discourage days. The native vegetation is mainly grasses, sedges, selective grazing, and reduce the extent of clumpy growth. and forbs. Fertilizer is needed to ensure the optimum growth of Typically, the surface layer is very dark gray clay about grasses and legumes. Grasses respond to nitrogen, and 12 inches thick. The next layer is very dark gray and very legumes respond to sulfur and phosphorus. dark grayish brown, calcareous clay about 24 inches thick. Solid-set sprinkler irrigation is the best method of The subsoil to a depth of 60 inches is grayish brown, controlling frost and providing adequate moisture for tree calcareous clay and gravelly sandy clay loam. The depth to fruit. Compaction can be minimized by limiting the use of bedrock is 60 inches or more. equipment when the soil is wet. A permanent cover crop Included in this unit are small areas of Carney and Darow helps to control runoff and erosion. soils on convex slopes; Cove and Gregory soils near This unit is poorly suited to homesite development. drainageways; Coker, Medford, and Phoenix soils; and soils The main limitations are the wetness, a high shrink-swell that are similar to the Padigan soil but have bedrock at a potential, the very slow permeability, and low strength. depth of 40 to 60 inches. Also included are small areas of This unit is poorly suited to standard systems of waste Padigan soils that have slopes of more than 3 percent. disposal because of the wetness and the very slow Included areas make up about 20 percent of the total permeability. Alternative waste disposal systems may acreage. function properly on this unit. Suitable included soils are Permeability is very slow in the Padigan soil. Available throughout the unit. Onsite investigation is needed to water capacity is about 8 inches. The effective rooting depth locate such soils. is limited by the water table, which is 1.0 foot above to 0.5 A drainage system is needed if roads or building foot below the surface from November through May. Runoff foundations are constructed on this unit. The wetness can is ponded, and the hazard of water erosion is slight. be reduced by installing drainage tile around footings. This unit is used mainly for pasture. It also is used for Properly designing foundations and footings, diverting tree fruit, hay, and homesite development. runoff away from the buildings, and backfilling with material This unit is suited to permanent pasture. It is limited that has a low shrink-swell potential help to prevent the mainly by the wetness, the high content of clay, and a slow structural damage caused by shrinking rate of water intake. Crops that require good and swelling. Properly designing buildings and roads helps of about 31 inches. The depth to bedrock ranges from 20 to offset the limited ability of the soil to support a load. to 40 inches. Revegetating as soon as possible helps to control Permeability is slow in the Dubakella soil. Available erosion in disturbed areas around construction sites. In water capacity is about 3 inches. The effective rooting many areas it may be necessary to haul in topsoil for lawns depth is 20 to 40 inches. Runoff is rapid, and the hazard and gardens. Because of a low amount of rainfall in of water erosion is high. summer, irrigation is needed in areas that support lawn This unit is used for wildlife habitat and limited timber grasses, shrubs, vines, shade trees, or ornamental trees. production. It is poorly suited to timber production. The plant The vegetative site is Poorly Drained Bottom. community on the Pearsoll soil includes scattered Jeffrey pine and an occasional incense cedar or Douglas fir. The 140G-Pearsoll-Dubakella complex, rocky, 20 to 60 understory vegetation is mainly sheep fescue, California percent slopes. This map unit is on hillslopes. Elevation is fescue, and Indian dream fern. 1,200 to 4,100 feet. The mean annual precipitation is 35 to The plant community on the Dubakella soil includes 60 inches, the mean annual temperature is 45 to 52 Douglas fir, Jeffrey pine, incense cedar, and Pacific degrees F, and the average frost-free period is 100 to 160 madrone. The understory vegetation is mainly canyon live days. The native vegetation on the Pearsoll soil is mainly oak, common snowberry, and California fescue. grasses, shrubs, and forbs and a few scattered conifers. On the basis of a 100-year, site curve, the mean site That on the Dubakella soil is mainly conifers and hardwoods index for Douglas fir is 80 on the Dubakella soil. The yield and an understory of grasses, shrubs, and forbs. at culmination of the mean annual increment is 4,060 cubic This unit is about 60 percent Pearsoll soil and 20 feet per acre in a fully stocked, even-aged stand of trees at percent Dubakella soil. The components of this unit occur 70 years and 23,360 board feet per acre (Scribner rule) at as areas so intricately intermingled that mapping them 160 years. On the basis of a 50-year curve, the mean site separately was not practical at the scale used. index is 60. Included in this unit are small areas of Rock outcrop on The main limitations affecting timber production on the ridges and convex slopes; Acker, Beekman, Gravecreek, Dubakella soil are the slope, low fertility, erosion, Josephine, Norling, and Speaker soils; and, on concave compaction, seedling mortality, and plant competition. slopes and foot slopes, soils that are similar to the Also, the bedrock restricts root growth. As a result, Dubakella soil but have bedrock at a depth of more than 40 windthrow is a hazard. inches. Also included are small areas of Pearsoll and When timber is harvested, management that minimizes Dubakella soils that have slopes of less than 20 or more the risk of erosion is essential. Wheeled and tracked logging than 60 percent. Included areas make up about 20 percent equipment can be used in the less sloping areas, but cable of the total acreage. yarding generally is safer and results in less surface The Pearsoll soil is shallow and well drained. It formed in disturbance. Rock outcrop and stones can cause breakage colluvium derived dominantly from peridotite and of falling timber and can hinder yarding. If the soil is serpentinite. Typically, the surface is covered with a layer of excessively disturbed when timber is harvested or logging needles, leaves, and twigs about 1/2 inch thick. , The roads are built, a larger number of rock fragments is left on surface layer is dark brown extremely stony clay loam about the surface. Using standard wheeled and tracked 7 inches thick. The subsoil is dark brown very cobbly and equipment when the soil is moist causes rutting and extremely cobbly clay about 12 inches thick. Bedrock is at a compaction. Puddling can occur when the soil is wet. Using depth of about 19 inches. The depth to bedrock ranges from low-pressure ground equipment causes less damage to the 10 to 20 inches. soil and helps to maintain productivity. Compaction can be Permeability is slow in the Pearsoll soil. Available minimized by using suitable methods of harvesting, laying water capacity is about 1 inch. The effective rooting out skid trails in advance, and harvesting timber when the depth is 10 to 20 inches. Runoff is rapid, and the soil is least susceptible to compaction. Ripping skid trails hazard of water erosion is high. and landings when the soil is dry can improve the growth of The Dubakella soil is moderately deep and well drained. plants. It formed in colluvium derived dominantly from peridotite Properly designed road drainage systems that include and serpentinite. Typically, the surface layer is dark reddish carefully located culverts help to control erosion. Areas that brown very stony clay loam about 11 inches thick. The have been cut and filled are easily eroded unless they are subsoil is dark reddish brown very cobbly clay about 20 treated. Seeding, mulching, and benching these areas help inches thick. Bedrock is at a depth to control erosion. Steep yarding paths, skid trails, and firebreaks are subject to rilling and gullying unless they are protected by a plant cover or adequate water bars, or both. Cutbanks 20 to 40 inches. In some areas the surface layer is occasionally slump when the soil is saturated. gravelly or cobbly. Constructing logging roads on the steeper slopes can Included in this unit are small areas of Carney soils on result in a high risk of erosion. Building the roads at convex slopes, Padigan soils on concave slopes, Coker and midslope requires extensive cutting and filling and removes Winlo soils, and soils that are similar to the Phoenix soil but land from production. Material that is discarded when the have bedrock at a depth of 40 to 60 inches. Also included roads are built can damage vegetation and is a potential are small areas of Phoenix soils that have slopes of more source of sedimentation. If the material becomes saturated, than 3 percent. Included areas make up about 10 percent of avalanches of debris can occur. End hauling of the waste the total acreage. material minimizes damage to vegetation downslope and Permeability is very slow in the Phoenix soil. Available reduces the risk of sedimentation. Skid trails and water capacity is about 4 inches. The effective rooting depth unsurfaced roads may be impassable during rainy periods. is limited by the water table, which is within a depth of 0.5 Logging roads require suitable surfacing for year-round use. foot from December through May. Runoff is slow, and the A high temperature in the surface layer during summer, hazard of water erosion is slight. the large number of rock fragments in the soil, and the low This unit is used mainly for hay and pasture or for available water capacity increase the seedling mortality tree fruit. It also is used for homesite development. rate. A high content of magnesium and low content of This unit is suited to permanent pasture. It is limited calcium also increase the seedling mortality rate. To mainly by wetness, the high content of clay, and a slow rate compensate for the expected high mortality rate, the larger of water intake. The ability of tile drains to remove seedlings or a greater number of seedlings should be subsurface water from the soil is limited because of the planted. When the timber is harvested, leaving some of the very slow permeability. larger trees unharvested provides shade for seedlings. The In summer, irrigation is needed for the maximum seedling mortality rate also can be reduced by providing production of most forage crops. Sprinkler irrigation is the artificial shade for seedlings. Reforestation can be best method of applying water. This method permits an accomplished by planting Jeffrey pine and incense cedar even, controlled application of water, helps to prevent seedlings. excessive runoff, and minimizes the risk of erosion. Border Undesirable plants limit natural or artificial and contour flood irrigation systems also are suitable. For reforestation unless intensive site preparation and the efficient application and removal of surface irrigation maintenance measures are applied. Mulching around water, land leveling is needed. Because of the very slow seedlings helps to maintain the moisture supply in permeability and depth to the water table, water summer and minimizes competition from undesirable applications should be regulated so that the water does not plants. stand on the surface and damage the crop. Land smoothing Increased erosion, loss of plant nutrients, and water and open ditches can reduce surface wetness. The use of repellency are likely to result from fires of moderate pipe, ditch lining, or drop structures in irrigation ditches intensity. reduces water loss and the hazard of erosion. The vegetative site in areas of the Pearsoll soil is Wetness limits the choice of suitable forage plants and Shallow Serpentine, 30- 40-inch precipitation zone, and the the period of cutting or grazing and increases the risk of one in areas of the Dubakella soil is Douglas Fir-Pine winterkill. The high content of clay severely limits tillage and Forest, Serpentine. root growth. Deep cracks form as the soil dries in summer. Proper stocking rates, pasture rotation, and restricted 141A-Phoenix clay, 0 to 3 perce nt slopes. This grazing during wet periods help to keep pastures in good moderately deep, poorly drained soil is on alluvial fans. It condition and protect the soil from erosion. Grazing when formed in alluvium derived dominantly from tuff and breccia. the soil is wet results in compaction of the surface layer, Elevation is 1,200 to 1,700 feet. The mean annual poor tilth, and excessive runoff. Periodic mowing and precipitation is 18 to 25 inches, the mean annual clipping help to maintain uniform plant growth, discourage temperature is 50 to 54 degrees F, and the average selective grazing, and reduce the extent of clumpy growth. frost-free period is 160 to 180 days. The native vegetation is Fertilizer is needed to ensure the optimum growth of grasses mainly grasses, sedges, and forbs. and legumes. Grasses respond to nitrogen, and legumes Typically, the surface layer is dark gray clay about 20 respond to sulfur and phosphorus. inches thick. The subsoil is dark gray and gray clay about Solid-set sprinkler irrigation is the best method of 20 inches thick. Weathered bedrock is at a depth of about controlling frost and providing adequate moisture for 40 inches. The depth to bedrock ranges from tree fruit. Compaction can be minimized by limiting the areas make up about 10 percent of the total acreage. use of equipment when the soil is wet. A permanent cover Permeability is moderately slow in the Pinehurst soil. crop helps to control runoff and erosion. Available water capacity is about 10 inches. The effective This unit is poorly suited to homesite development. The rooting depth is 60 inches or more. Runoff is slow, and the main limitations are the wetness, a high shrink-swell hazard of water erosion is slight. potential, the very slow permeability, the depth to bedrock, This unit is used for timber production, livestock and low strength. grazing, and wildlife habitat. This unit is poorly suited to standard systems of waste This unit is suited to the production of Douglas fir and disposal because of the wetness, the depth to bedrock, white fir. Other species that grow on this unit include and the very slow permeability. Alternative waste Pacific yew and sierra chinkapin. The understory disposal systems may function properly on this unit. vegetation includes onesided wintergreen, cascade Suitable included soils are throughout the unit. Onsite Oregongrape, and American twinflower. investigation is needed to locate such soils. On the basis of a 100-year site curve, the mean site A drainage system is needed if roads or building index for Douglas fir is 110. The yield at culmination of the foundations are constructed on this unit. The wetness can mean annual increment is 5,880 cubic feet per acre in a be reduced by installing drainage tile around footings. fully stocked, even-aged stand of trees at 60 years and Properly designing foundations and footings, diverting 48,300 board feet per acre (Scribner rule) at 140 years. On runoff away from the buildings, and backfilling with material the basis of a 50-year curve, the mean site index is 75. that has a low shrink-swell potential help to prevent the On the basis of a 50-year site curve, the mean site index structural damage caused by shrinking and swelling. for white fir is 75. The yield at culmination of the mean Properly designing buildings and roads helps to offset the annual increment is 12,530 cubic feet per acre in a fully limited ability of the soil to support a load. stocked, even-aged stand of trees at 70 years. Revegetating as soon as possible helps to control The main limitations affecting timber production are erosion in disturbed areas around construction sites. In compaction, erosion, seedling mortality, and plant many areas it may be necessary to haul in topsoil for lawns competition. Conventional methods of harvesting timber and gardens. Because of a low amount of rainfall in generally are suitable, but the soil may be compacted if it is summer, irrigation is needed in areas that support lawn moist when heavy equipment is used. Puddling can occur grasses, shrubs, vines, shade trees, or ornamental trees. when the soil is wet. Using low-pressure ground equipment The vegetative site is Poorly Drained Bottom. causes less damage to the soil and helps to maintain productivity. Compaction can be minimized by using 142C-Pinehurst loam, 3 to 12 percent slopes. This suitable methods of harvesting, laying out skid trails in very deep, well drained soil is on plateaus. It formed in advance, and harvesting timber when the soil is least colluvium derived from basalt and andesite. Elevation is susceptible to compaction. Ripping skid trails and landings 3,600 to 5,500 feet. The mean annual precipitation is 30 to when the soil is dry can improve the growth of plants. 55 inches, the mean annual temperature is 40 to 45 degrees Erosion can be controlled by carefully planning the F, and the average frost-free period is less than 100 days. construction and maintenance of logging roads, skid trails, The native vegetation is mainly conifers and an understory and landings. Seeding, mulching, and benching areas that of grasses, shrubs, and forbs. have been cut and filled also help to control erosion. Skid Typically, the surface is covered with a layer of needles trails and unsurfaced roads may be impassable during and twigs about 1 inch thick. The surface layer is dark rainy periods. Logging roads require suitable surfacing for reddish brown loam about 15 inches thick. The subsoil to a year-round use. depth of 60 inches is dark reddish brown clay loam. The Severe frost can damage or kill seedlings. Air depth to bedrock is 60 inches or more. In some areas the drainage is restricted on this unit. Proper timber surface layer is stony. harvesting methods can reduce the effect of frost on Included in this unit are small areas of Kanutchan and regeneration. Reforestation can be accomplished by Sibannac soils in basins and near drainageways, Bybee planting seedlings of frost-tolerant species, such as and Tatouche soils on concave slopes, Farva and ponderosa pine and lodgepole pine. Woodseye soils and Rock outcrop on convex slopes, and Undesirable plants limit natural or artificial soils that are similar to the Pinehurst soil but have bedrock reforestation unless intensive site preparation and within a depth of 60 inches. Also included are small areas maintenance measures are applied. Mulching around of Pinehurst soils that have slopes of less than 3 or more seedlings helps to maintain the moisture supply in than 12 percent. Included summer and minimizes competition from undesirable medium, and the hazard of water erosion is moderate. plants. This unit is used for timber production, livestock The main limitation affecting livestock grazing is grazing, and wildlife habitat. compaction. The native vegetation suitable for grazing This unit is suited to the production of Douglas fir and includes western fescue, mountain brome, tall trisetum, and white fir. Other species that grow on this unit include Alaska oniongrass. If the understory is overgrazed, the Pacific yew and sierra chinkapin. The understory proportion of preferred forage plants decreases and the vegetation includes onesided wintergreen, cascade proportion of less preferred forage plants increases. Oregongrape, and American twinflower. A planned grazing system that includes timely deferment On the basis of a 100-year site curve, the mean site of grazing, rotation grazing, and proper livestock distribution index for Douglas fir is 115. The yield at culmination of the helps to prevent overgrazing of the understory and damage mean annual increment is 6,360 cubic feet per acre in a to the soil. Grazing should be delayed until the more fully stocked, even-aged stand of trees at 60 years and desirable forage plants have achieved enough growth to 48,300 board feet per acre (Scribner rule) at 140 years. On withstand grazing pressure and the soil is firm enough to the basis of a 50-year curve, the mean site index is 85. withstand trampling by livestock. On the basis of a 50-year site curve, the mean site index Thinning, logging, and fire reduce the density of the for white fir is 75. The yield at culmination of the mean overstory canopy and increase the production of annual increment is 12,570 cubic feet per acre in a fully understory vegetation. Areas that support a large amount stocked, even-aged stand of trees at 70 years. of competing vegetation can be improved by prescribed The main limitations affecting timber production are burning or by chemical or mechanical treatment. Seeding erosion, compaction, plant competition, and seedling disturbed areas to suitable plants increases forage mortality. Wheeled and tracked logging equipment can be production and reduces the risk of erosion. used in the less sloping areas, but cable yarding generally The vegetative site is Mixed Fir-Yew Forest. is safer in the more sloping areas and results in less surface disturbance. Using standard wheeled and tracked 143E-Pinehurst loam, 12 to 35 percent north slopes. equipment when the soil is moist causes rutting and This very deep, well drained soil is on hillslopes. It formed compaction. Puddling can occur when the soil is wet. Using in colluvium derived from basalt and andesite. Elevation is low-pressure ground equipment causes less damage to the 3,600 to 5,500 feet. The mean annual precipitation is 30 to soil and helps to maintain productivity. Compaction can be 55 inches, the mean annual temperature is 40 to 45 minimized by using suitable methods of harvesting, laying degrees F, and the average frost-free period is less than out skid trails in advance, and harvesting timber when the 100 days. The native vegetation is mainly conifers and an soil is least susceptible to compaction. Ripping skid trails understory of grasses, shrubs, and forbs. and landings when the soil is dry can improve the growth of Typically, the surface is covered with a layer of needles plants. and twigs about 1 inch thick. The surface layer is dark Properly designed road drainage systems that include reddish brown loam about 15 inches thick. The subsoil to-a carefully located culverts help to control erosion. Seeding, depth of 60 inches is dark reddish brown clay loam. The mulching, and benching areas that have been cut and filled depth to bedrock is 60 inches or more. In some areas the also help to control erosion. Steep yarding paths, skid trails, surface layer is stony. and firebreaks are subject to rilling and gullying unless they Included in this unit are small areas of Kanutchan and are protected by a plant cover or adequate water bars, or Sibannac soils in basins and near drainageways, Bybee both. Skid trails and unsurfaced roads may be impassable and Tatouche soils on concave slopes, Farva and during rainy periods. Logging roads require suitable Woodseye soils and Rock outcrop on ridges and convex surfacing for year-round use. slopes, and soils that are similar to the Pinehurst soil but Undesirable plants limit natural or artificial reforestation have bedrock within a depth of 60 inches. Also included unless intensive site preparation and maintenance are small areas of Pinehurst soils that have slopes of less measures are applied. Reforestation can be accomplished than 12 or more than 35 percent. Included areas make up by planting ponderosa pine and Douglas fir seedlings. about 20 percent of the total acreage. Mulching around seedlings helps to maintain the moisture Permeability is moderately slow in the Pinehurst soil. supply in summer and minimizes competition from Available water capacity is about 10 inches. The effective undesirable plants. rooting depth is 60 inches or more. Runoff is Severe frost can damage or kill seedlings. In the less sloping areas where air drainage may be restricted, proper timber harvesting methods can reduce the effect of effective rooting depth is 60 inches or more. Runoff is frost on regeneration. medium, and the hazard of water erosion is moderate. The main limitations affecting livestock grazing are This unit is used for timber production, livestock compaction and erosion. The native vegetation suitable for grazing, and wildlife habitat. grazing includes western fescue, mountain brome, tall This unit is suited to the production of Douglas fir and trisetum, and Alaska oniongrass. If the understory is white fir. Other species that grow on this unit include overgrazed, the proportion of preferred forage plants ponderosa pine and incense cedar. The understory decreases and the proportion of less preferred forage vegetation includes Pacific serviceberry, tall Oregon grape, plants increases. and common snowberry. A planned grazing system that includes timely deferment On the basis of a 100-year site curve, the mean site of grazing, rotation grazing, and proper livestock distribution index for Douglas fir is 110. The yield at culmination of the helps to prevent overgrazing of the understory and damage mean annual increment is 5,880 cubic feet per acre in a to the soil. Grazing should be delayed until the more fully stocked, even-aged stand of trees at 60 years and desirable forage plants have achieved enough growth to 37,120 board feet per acre (Scribner rule) at 160 years. On withstand grazing pressure and the soil is firm enough to the basis of a 50-year curve, the mean site index is 75. withstand trampling by livestock. On the basis of a 50-year site curve, the mean site index Thinning, logging, and fire reduce the density of the for white fir is 75. The yield at culmination of the mean overstory canopy and increase the production of annual increment is 12,530 cubic feet per acre in a fully understory vegetation. Areas that support a large amount stocked, even-aged stand of trees at 70 years. of competing vegetation can be improved by prescribed The main limitations affecting timber production are burning or by chemical or mechanical treatment. Seeding erosion, compaction, seedling mortality, and plant disturbed areas to suitable plants increases forage competition. Wheeled and tracked logging equipment can production and reduces the risk of erosion. be used in the less sloping areas, but cable yarding The vegetative site is Mixed Fir-Yew Forest. generally is safer in the more sloping areas and results in less surface disturbance. Using standard wheeled and 144E-Pinehurst loam, 12 to 35 percent south slopes. tracked equipment when the soil is moist causes rutting and This very deep, well drained soil is on hillslopes. It formed compaction. Puddling can occur when the soil is wet. Using in colluvium derived from basalt and andesite. Elevation is low-pressure ground equipment causes less damage to the 3,600 to 5,500 feet. The mean annual precipitation is 30 to soil and helps to maintain productivity. Compaction can be 55 inches, the mean annual temperature is 40 to 45 minimized by using suitable methods of harvesting, laying degrees F, and the average frost-free period is less than out skid trails in advance, and harvesting timber when the 100 days. The native vegetation is mainly conifers and an soil is least susceptible to compaction. Ripping skid trails understory of grasses, shrubs, and forbs. and landings when the soil is dry can improve the growth of Typically, the surface is covered with a layer of needles plants. and twigs about 1 inch thick. The surface layer is dark Properly designed road drainage systems that include reddish brown loam about 15 inches thick. The subsoil to a carefully located culverts help to control erosion. Seeding, depth of 60 inches is dark reddish brown clay loam. The mulching, and benching areas that have been cut and filled depth to bedrock is 60 inches or more. In some areas the also help to control erosion. Steep yarding paths, skid trails, surface layer is stony. and firebreaks are subject to rilling and gullying unless they Included in this unit are small areas of Kanutchan and are protected by a plant cover or adequate water bars, or Sibannac soils in basins and near drainageways, Bybee both. Skid trails and unsurfaced roads may be impassable and Tatouche soils on concave slopes, Farva and during rainy periods. Logging roads require suitable Woodseye soils and Rock outcrop on ridges and convex surfacing for year-round use. slopes, and soils that are similar to the Pinehurst soil but A high temperature in the surface layer and an have bedrock within a depth of 60 inches. Also included are insufficient moisture supply in summer increase the seedling small areas of Pinehurst soils that have slopes of less than mortality rate. To compensate for the expected high 12 or more than 35 percent. Included areas make up about mortality rate, the larger seedlings or a greater number of 20 percent of the total acreage. seedlings should be planted. When the timber is harvested, Permeability is moderately slow in the Pinehurst soil. leaving some of the larger trees unharvested provides Available water capacity is about 10 inches. The shade for seedlings. Reforestation can be accomplished by planting than 12 percent. Included areas make up about 15 ponderosa pine and Douglas fir seedlings. percent of the total acreage. Severe frost can damage or kill seedlings. In the less The Pinehurst soil is very deep and well drained. It sloping areas where air drainage may be restricted, proper formed in colluvium derived dominantly from andesite. timber harvesting methods can reduce the effect of frost on Typically, the surface is covered with a layer of needles and regeneration. twigs about 1 inch thick. The surface layer is dark reddish Undesirable plants limit natural or artificial brown loam about 15 inches thick. The subsoil is dark reforestation unless intensive site preparation and reddish brown clay loam about 45 inches thick. The depth maintenance measures are applied. Mulching around to bedrock is 60 inches or more. In some areas the surface seedlings helps to maintain the moisture supply in layer is stony. summer and minimizes competition from undesirable Permeability is moderately slow in the Pinehurst soil. plants. Available water capacity is about 10 inches. The effective The main limitations affecting livestock grazing are rooting depth is 60 inches or more. Runoff is slow, and the compaction and erosion. The native vegetation suitable for hazard of water erosion is slight. grazing includes western fescue, mountain brome, tall The Greystoke soil is deep and well drained. It formed in trisetum, and Alaska oniongrass. If the understory is residuum and colluvium derived dominantly from andesite. overgrazed, the proportion of preferred forage plants Typically, the surface is covered with a layer of needles and decreases and the proportion of less preferred forage twigs about 1 inch thick. The surface layer is dark reddish plants increases. brown stony loam about 3 inches thick. The next layer is A planned grazing system that includes timely deferment dark reddish brown very cobbly loam about 10 inches thick. of grazing, rotation grazing, and proper livestock distribution The upper 10 inches of the subsoil also is dark reddish helps to prevent overgrazing of the understory and damage brown very cobbly loam. The lower 19 inches is dark reddish to the soil. Grazing should be delayed until the more brown extremely gravelly clay loam. Weathered bedrock is desirable forage plants have achieved enough growth to at a depth of about 42 inches. The depth to bedrock ranges withstand grazing pressure and the soil is firm enough to from 40 to 60 inches. withstand trampling by livestock. Permeability is moderately slow in the Greystoke soil. Thinning, logging, and fire reduce the density of the Available water capacity is about 4 inches. The effective overstory canopy and increase the production of rooting depth is 40 to 60 inches. Runoff is slow, and the understory vegetation. Areas that support a large amount hazard of water erosion is slight. of competing vegetation can be improved by prescribed This unit is used for timber production, livestock burning or by chemical or mechanical treatment. Seeding grazing, and wildlife habitat. disturbed areas to suitable plants increases forage This unit is suited to the production of Douglas fir and production and reduces the risk of erosion. ponderosa pine. Other species that grow on this unit The vegetative site is Mixed Fir-Serviceberry Forest. include incense cedar, white fir, and sugar pine. The understory vegetation includes tall Oregon grape, 145C-Pinehurst-Greystoke complex, 1 to 12 percent pachystima, and western fescue. slopes. This map unit is on plateaus. Elevation is 3,500 to On the basis of a 100-year site curve, the mean site 4,800 feet. The mean annual precipitation is 20 to 30 index for Douglas fir is 100 on the Pinehurst soil. The yield inches, the mean annual temperature is 42 to 46 degrees F, at culmination of the mean annual increment is 5,040 cubic and the average frost-free period is less than 100 days. The feet per acre in a fully stocked, even-aged stand of trees at native vegetation is mainly conifers and an understory of 60 years and 39,750 board feet per acre (Scribner rule) at grasses, shrubs, and forbs. 150 years. On the basis of a 50-year curve, the mean site This unit is about 65 percent Pinehurst soil and 20 index is 75. percent Greystoke soil. The components of this unit occur On the basis of a 100-year site curve, the mean site as areas so intricately intermingled that mapping them index for ponderosa pine is 95 on the Pinehurst soil. The separately was not practical at the scale used. yield at culmination of the mean annual increment is 3,760 Included in this unit are small areas of Merlin and Royst cubic feet per acre in a fully stocked, even-aged stand of soils, Rock outcrop and Kanutchan soils near drainageways trees at 40 years and 43,160 board feet per acre (Scribner and on concave slopes, and soils that are similar to the rule) at 130 years. Pinehurst soil but have bedrock within a depth of 60 inches. On the basis of a 100-year site curve, the mean site Also included are small areas of Pinehurst and Greystoke index for Douglas fir is 90 on the Greystoke soil. The yield soils that have slopes of more at culmination of the mean annual increment is 4,200 cubic feet per acre in a fully stocked, even-aged stand of trees at 60 years and 31,840 board feet per acre delayed until the more desirable forage plants have (Scribner rule) at 160 years. On the basis of a 50-year achieved enough growth to withstand grazing pressure and curve, the mean site index is 65. the soils are firm enough to withstand trampling by On the basis of a 100-year site curve, the mean site livestock. index for ponderosa pine is 90 on the Greystoke soil. The Thinning, logging, and fire reduce the density of the yield at culmination of the mean annual increment is 3,400 overstory canopy and increase the production of cubic feet per acre in a fully stocked, even-aged stand, of understory vegetation. Areas that support a large amount trees at 40 years and 37,960 board feet per acre (Scribner of competing vegetation can be improved by prescribed rule) at 130 years. burning or by chemical or mechanical treatment. Seeding The main limitations affecting timber production are disturbed areas to suitable plants increases forage compaction, erosion, seedling mortality, and plant production and reduces the risk of erosion. competition. Conventional methods of harvesting timber The vegetative site is Douglas Fir-Mixed Pine-Sedge generally are suitable, but the soils may be compacted if Forest. they are moist when heavy equipment is used. Puddling can occur when the soils are wet. If the soils are 146-Pits, gravel. This map unit consists of sand and excessively disturbed when timber is harvested or logging gravel pits and quarries. The pits are on flood plains and roads are built, a larger number of rock fragments is left on terraces along the major streams and rivers in the survey the surface. Using low-pressure ground equipment causes area. They are a major source of aggregate used in the less damage to the soils and helps to maintain productivity. construction of roads. Compaction can be minimized by using suitable methods of The quarries are on foothills and uplands. They are an harvesting, laying out skid trails in advance, and harvesting excellent source of the various kinds of rock that are used timber when the soils are least susceptible to compaction. for most of the roads built in the survey area. Ripping skid trails and landings when the soils are dry can This unit is not assigned to a vegetative site. improve the growth of plants. Erosion can be controlled by carefully planning the 147C-Pokegema-Woodcock complex, 1 to 12 percent construction and maintenance of logging roads, skid trails, slopes. This map unit is on plateaus. Elevation is 3,800 to and landings. Seeding, mulching, and benching areas that 6,600 feet. The mean annual precipitation is 25 to 35 have been cut and filled also help to control erosion. Skid inches, the mean annual temperature is 40 to 43 degrees F, trails and unsurfaced roads may be impassable during and the average frost-free period is less than 100 days. The rainy periods. Logging roads require suitable surfacing for native vegetation is mainly conifers and an understory of year-round use. grasses, shrubs, and forbs. Severe frost can damage or kill seedlings. Air This unit is about 70 percent Pokegema soil and 20 drainage is restricted on this unit. Proper timber percent Woodcock soil. The components of this unit occur harvesting methods can reduce the effect of frost on as areas so intricately intermingled that mapping them regeneration. Reforestation can be accomplished by separately was not practical at the scale used. planting seedlings of frost-tolerant species, such as Included in this unit are small areas of Merlin soils, Rock ponderosa pine and lodgepole pine. outcrop, Klamath soils near drainageways and on concave Undesirable plants limit natural or artificial slopes, soils that are similar to the Pokegema soil but have reforestation unless intensive site preparation and bedrock at a depth of less than 40 or more than 60 inches, maintenance measures are applied. Mulching around and soils that are similar to the Woodcock soil but have seedlings helps to maintain the moisture supply in bedrock within a depth of 60 inches. Also included are small summer and minimizes competition from undesirable areas of Pokegema and Woodcock soils that have slopes of plants. more than 12 percent. Included areas make up about 10 The main limitation affecting livestock grazing is percent of the total acreage. compaction. The native vegetation suitable for grazing The Pokegema soil is deep and well drained. It formed in includes western fescue, mountain brome, and tall trisetum. residuum derived dominantly from andesite. Typically, the If the understory is overgrazed, the proportion of preferred surface is covered with a layer of needles and twigs about forage plants decreases and the proportion of less 1/2 inch thick. The surface layer is dark reddish brown loam preferred forage plants increases. about 8 inches thick. The upper 8 inches of the subsoil is A planned grazing system that includes timely deferment dark reddish brown clay loam. The lower 22 inches is dark of grazing, rotation grazing, and proper livestock distribution reddish brown gravelly clay The substratum is dark reddish helps to prevent overgrazing of the understory and damage brown and reddish to the soils. Grazing should be brown gravelly clay about 14 inches thick. Weathered trails, and landings. Seeding, mulching, and benching bedrock is at a depth of about 52 inches. The depth to areas that have been cut and filled also help to control bedrock ranges from 40 to 60 inches: In some areas the erosion. Skid trails and unsurfaced roads may be surface layer is stony. impassable during rainy periods. Logging roads require Permeability is moderately slow in the Pokegema suitable surfacing for year-round use. soil. Available water capacity is about 6 inches. The Severe frost can damage or kill seedlings. Air effective rooting depth is 40 to 60 inches. Runoff is drainage is restricted on the unit. Proper timber slow, and the hazard of water erosion is slight. harvesting methods can reduce the effect of frost on The Woodcock soil is very deep and well drained. It regeneration. Reforestation can be accomplished by formed in colluvium derived dominantly from andesite. planting seedlings of frost-tolerant species, such as Typically, the surface is covered with a layer of needles and ponderosa pine and lodgepole pine. twigs about 1 inch thick. The surface layer is dark reddish Undesirable plants limit natural or artificial brown stony loam about 4 inches thick. The next layer is reforestation unless intensive site preparation and dark reddish brown very gravelly loam about 12 inches maintenance measures are applied. Mulching around thick. The subsoil is dark reddish -brown very gravelly clay seedlings helps to maintain the moisture supply in loam about 23 inches thick. The substratum to a depth of summer and minimizes competition from undesirable 62 inches is dark reddish brown gravelly clay loam. The plants. depth to bedrock is 60 inches or more. The main limitation affecting livestock grazing is Permeability is moderate in the Woodcock soil. Available compaction. The native vegetation suitable for grazing water capacity is about 4 inches. The effective rooting depth includes western fescue, sedge, mountain brome, and tall is 60 inches or more. Runoff is slow, and the hazard of trisetum. If the understory is overgrazed, the proportion of water erosion is slight. preferred forage plants decreases and the proportion of This unit is used for timber production, livestock less preferred forage plants increases. grazing, and wildlife habitat. A planned grazing system that includes timely deferment This unit is suited to the production of Douglas fir and of grazing, rotation grazing, and proper livestock distribution ponderosa pine. Other species that grow on this unit include helps to prevent overgrazing of the understory and damage white fir, incense cedar, and sugar pine. The understory to the soils. Grazing should be delayed until the more vegetation includes sierra chinkapin, tall Oregon grape, and desirable forage plants have achieved enough growth to western fescue. withstand grazing pressure and the soils are firm enough to On the basis of a 100-year site curve, the mean site withstand trampling by livestock. index for Douglas fir is 120 on the Pokegema soil and 110 Thinning, logging, and fire reduce the density of the on the Woodcock soil. overstory canopy and increase the production of On the basis of a 100-year site curve, the mean site understory vegetation. Areas that support a large amount index for ponderosa pine is 105 on both the Pokegema and of competing vegetation can be improved by prescribed Woodcock soils. The yield at culmination of the mean burning or by chemical or mechanical treatment. Seeding annual increment is 4,480 cubic feet per acre in a fully disturbed areas to suitable plants increases forage stocked, even-aged stand of trees at 40 years and 50,040 production. board feet per acre (Scribner rule) at 120 years. The vegetative site is Mixed Conifer-Chinkapin- The main limitations affecting timber production are Sedge Forest. compaction, erosion, seedling mortality, and plant competition. Conventional methods of harvesting timber 148C-Pokegema-Woodcock complex, warm, 1 to 12 generally are suitable, but the soils may be compacted if percent slopes. This map unit is on plateaus. Elevation is they are moist when heavy equipment is used. Puddling can 4,300 to 5,000 feet. The mean annual precipitation is 25 to occur when the soils are wet. Using low-pressure ground 35 inches, the mean annual temperature is 40 to 43 equipment causes less damage to the soils and helps to degrees F, and the average frost-free period is less than maintain productivity. Compaction can be minimized by 100 days. The native vegetation is mainly conifers and an using suitable methods of harvesting, laying out skid trails in understory of grasses, shrubs, and forbs. advance, and harvesting timber when the soils are least This unit is about 70 percent Pokegema soil and 20 susceptible to compaction. Ripping skid trails and landings percent Woodcock soil. The components of this unit occur when the soils are dry can improve the growth of plants. as areas so intricately intermingled that mapping them Erosion can be controlled by carefully planning the separately was not practical at the scale used. construction and maintenance of logging roads, skid Included in this unit are small areas of Merlin soils, small areas of Rock outcrop, and small areas of Klamath mean annual increment is 4,480 cubic feet per acre in a fully and Kanutchan Variant soils near drainageways and on stocked, even-aged stand of trees at 40 years and 50,040 concave slopes. Also included are small areas of soils that board feet per acre (Scribner rule) at 120 years. are similar to the Pokegema soil but have bedrock at a The main limitations affecting timber production are depth of less than 40 or more than 60 inches, soils that are compaction, erosion, seedling mortality, and plant similar to the Woodcock soil but have bedrock within a competition. Conventional methods of harvesting timber depth of 60 inches, and Pokegema and Woodcock soils that generally are suitable, but the soils may be compacted if have slopes of more than 12 percent. Included areas make they are moist when heavy equipment is used. Puddling can up about 10 percent of the total acreage. occur when the soils are wet. Using low-pressure ground The Pokegema soil is deep and well drained. It formed in equipment causes less damage to the soils and helps to residuum derived dominantly from andesite. Typically, the maintain productivity. Compaction can be minimized by surface is covered with a layer of needles and twigs about using suitable methods of harvesting, laying out skid trails in 1/2 inch thick. The surface layer is dark reddish brown loam advance, and harvesting timber when the soils are least about 8 inches thick. The upper 8 inches of the subsoil is susceptible to compaction. Ripping skid trails and landings dark reddish brown clay loam. The lower 22 inches is dark when the soils are dry can improve the growth of plants. reddish brown gravelly clay. The substratum is dark reddish Erosion can be controlled by carefully planning the brown and reddish brown gravelly clay about 14 inches construction and maintenance of logging roads, skid trails, thick. Weathered bedrock is at a depth of about 52 inches. and landings. Seeding, mulching, and benching areas that The depth to bedrock ranges from 40 to 60 inches. In some have been cut and filled also help to control erosion. Skid areas the surface layer is stony. trails and unsurfaced roads may be impassable during Permeability is moderately slow in the Pokegema soil. rainy periods. Logging roads require suitable surfacing for Available water capacity is about 66 inches. The year-round use. effective rooting depth is 40 to 60 inches. Runoff is slow, Severe frost can damage or kill seedlings. Air and the hazard of water erosion is slight. drainage is restricted on the unit. Proper timber The Woodcock soil is very deep and well drained. It harvesting methods can reduce the effect of frost on formed in colluvium derived dominantly from andesite. regeneration. Reforestation can be accomplished by Typically, the surface is covered with a layer of needles and planting seedlings of frost-tolerant species, such as twigs about 1 inch thick. The surface layer is dark reddish ponderosa pine and lodgepole pine. brown stony loam about 4 inches thick. The next layer is Undesirable plants limit natural or artificial dark reddish brown very gravelly loam about 12 inches reforestation unless intensive site preparation and thick. The subsoil is dark reddish brown very gravelly clay maintenance measures are applied. Mulching around loam about 23 inches thick. The substratum to a depth of seedlings helps to maintain the moisture supply in 62 inches is dark reddish brown gravelly clay loam. The summer and minimizes competition from undesirable depth to bedrock is 60 inches or more. plants. Permeability is moderate in the Woodcock soil. Available The main limitation affecting livestock grazing is water capacity is about 4 inches. The effective rooting depth compaction. The native vegetation suitable for grazing is 60 inches or more. Runoff is slow, and the hazard of includes western fescue, sedge, mountain brome, and tall water erosion is slight. trisetum. If the understory is overgrazed, the proportion of This unit is used for timber production, livestock preferred forage plants decreases and the proportion of grazing, and wildlife habitat. less preferred forage plants increases. This unit is suited to the production of Douglas fir and A planned grazing system that includes timely deferment ponderosa pine. Other species that grow on this unit of grazing, rotation grazing, and proper livestock distribution include white fir, incense cedar, and sugar pine. The helps to prevent overgrazing of the understory and damage understory vegetation includes sierra chinkapin, to the soils. Grazing should be delayed until the more antelope bitterbrush, and western fescue. desirable forage plants have achieved enough growth to On the basis of a 100-year site curve, the mean site withstand grazing pressure and the soils are firm enough to index for Douglas fir is 120 on the Pokegema soil and 110 withstand trampling by livestock. on the Woodcock soil. Thinning, logging, and fire reduce the density of the On the basis of a 100-year site curve, the mean site overstory canopy and increase the production of index for ponderosa pine is 105 on both the Pokegema understory vegetation. Areas that support a large amount and Woodcock soils. The yield at culmination of the of competing vegetation can be improved by prescribed burning or by chemical or mechanical treatment. Seeding disturbed areas to suitable plants methods of harvesting, laying out skid trails in advance, and increases forage production. harvesting timber when the soil is least susceptible to The vegetative site is Mixed Conifer-Bitterbrush- compaction. Ripping skid trails and landings when the soil Sedge Forest. is dry can improve the growth of plants. Erosion can be controlled by carefully planning the 149B-Pollard loam, 2 to 7 percent slopes. This very construction and maintenance of logging roads, skid trails, deep, well drained soil is on alluvial fans. It formed in and landings. Seeding, mulching, and benching areas that alluvium derived dominantly from metamorphic rock. have been cut and filled also help to control erosion. Skid Elevation is 1,200 to 4,000 feet. The mean annual trails and unsurfaced roads may be impassable during precipitation is 40 to 50 inches, the mean annual rainy periods. Logging roads require suitable surfacing for temperature is 45 to 52 degrees F, and the average year-round use. frost-free period is 100 to 160 days. The native vegetation is Undesirable plants limit natural or artificial reforestation mainly conifers and an understory of grasses, shrubs, and unless intensive site preparation and maintenance forbs. measures are applied. Reforestation can be accomplished Typically, the surface is covered with a layer of needles, by planting Douglas fir and ponderosa pine seedlings. leaves, and twigs about 2 inches thick. The surface layer is Mulching around seedlings helps to maintain the moisture dark brown loam about 11 inches thick. The upper 25 inches supply in summer and minimizes competition from of the subsoil is dark reddish brown clay loam. The lower 25 undesirable plants. inches is yellowish red and brown clay loam. The depth to This unit is well suited to irrigated crops. It is limited bedrock is 60 inches or more. In some areas the surface mainly by the moderately slow permeability. In summer, layer is clay loam or gravelly loam. irrigation is needed for the maximum production of most Included in this unit are small areas of Abegg, crops. Sprinkler irrigation is the best method of applying Josephine, and Wolfpeak soils; poorly drained soils near water. This method permits an even, controlled application drainageways and on concave slopes; and Pollard soils of water, helps to prevent excessive runoff, and minimizes that have slopes of more than 7 percent. Included areas the risk of erosion. Border and contour flood irrigation make up about 15 percent of the total acreage. systems also are suitable. For the efficient application and Permeability is slow in the Pollard soil. Available water removal of surface irrigation water, land leveling is needed. capacity is about 7 inches. The effective rooting depth is To prevent overirrigation and excessive erosion, 60 inches or more. Runoff is slow, and the hazard of applications of irrigation water should be adjusted to the water erosion is slight. available water capacity, the rate of water intake, and the This unit is used mainly for timber production, hay needs of the crop. The use of pipe, ditch lining, or drop and pasture, or wildlife habitat. It also is used for structures in irrigation ditches reduces water loss and the homesite development. hazard of erosion. This unit is suited to the production of Douglas fir. Other Returning all crop residue to the soil and using a species that grow on this unit include ponderosa pine, cropping system that includes grasses, legumes, or sugar pine, and California black oak. The understory grass-legume mixtures help to maintain fertility and tilth. vegetation includes canyon live oak, deerbrush, and Leaving crop residue on or near the surface helps to western fescue. conserve moisture and control erosion. On the basis of a 100-year site curve, the mean site A tillage pan forms easily if the soil is tilled when wet. index for Douglas fir is 125. The yield at culmination of the Chiseling or subsoiling breaks up the pan. Surface crusting mean annual increment is 7,320 cubic feet per acre in a and compaction can be minimized by returning crop residue fully stocked, even-aged stand of trees at 60 years and to the soil. 58,200 board feet per acre (Scribner rule) at 120 years. On Proper stocking rates, pasture rotation, and restricted the basis of a 50-year curve, the mean site index is 95. grazing during wet periods help to keep pastures in good The main limitations affecting timber production are condition and protect the soil from erosion. Grazing when the compaction and plant competition. Conventional methods of soil is wet results in compaction of the surface layer, poor harvesting timber generally are suitable, but the soil may be tilth, and excessive runoff. Periodic mowing and clipping help compacted if it is moist when heavy equipment is used. to maintain uniform plant growth, discourage selective Puddling can occur when the soil is wet. Using low-pressure grazing, and reduce the extent of clumpy growth. Fertilizer is ground equipment causes less damage to the soil and helps needed to ensure the optimum growth of grasses and to maintain productivity. Compaction can be minimized by legumes. . Grasses respond to nitrogen, and legumes using suitable respond to sulfur and phosphorus. This unit is well suited to homesite development. The main limitations are the moderately slow permeability and understory vegetation includes canyon live oak, the shrink-swell potential. The moderately slow deerbrush, and western fescue. permeability can be overcome by increasing the size of the On the basis of a 100-year site curve, the mean site absorption field. index for Douglas fir is 125. The yield at culmination of the If buildings are constructed on this unit, properly mean annual increment is 7,320 cubic feet per acre in a designing foundations and footings, diverting runoff away fully stocked, even-aged stand of trees at 60 years and from the buildings, and backfilling with material that has a 58,200 board feet per acre (Scribner rule) at 120 years. On low shrink -swell potential help to prevent the structural the basis of a 50-year curve, the mean site index is 95. damage caused by shrinking and swelling. Properly The main limitations affecting timber production are designing buildings and roads helps to offset the limited compaction, erosion, and plant competition. Conventional ability of the soil to support a load. methods of harvesting timber generally are suitable, but the Revegetating as soon as possible helps to control soil may be compacted if it is moist when heavy equipment erosion in disturbed areas around construction sites. is used. Puddling can occur when the soil is wet. Using Topsoil can be stockpiled and used to reclaim areas low-pressure ground equipment causes less damage to the disturbed during construction. Because of a low amount of soil and helps to maintain productivity. Compaction can be rainfall in summer, irrigation is needed in areas that support minimized by using suitable methods of harvesting, laying lawn grasses, shrubs, vines, shade trees, or ornamental out skid trails in advance, and harvesting timber when the trees. soil is least susceptible to compaction. Ripping skid trails The vegetative site is Douglas Fir-Black Oak Forest. and landings when the soil is dry can improve the growth of plants. 149D-Pollard loam, 7 to 20 percent sl opes. This very Erosion can be controlled by carefully planning the deep, well drained soil is on alluvial fans. It formed in construction and maintenance of logging roads, skid trails, alluvium derived dominantly from metamorphic rock. and landings. Seeding, mulching, and benching areas that Elevation is 1,200 to 4,000 feet. The mean annual have been cut and filled also help to control erosion. Skid precipitation is 40 to 50 inches, the mean annual trails and unsurfaced roads may be impassable during temperature is 45 to 52 degrees F, and the average rainy periods. Logging roads require suitable surfacing for frost-free period is 100 to 160 days. The native vegetation year-round use. is mainly conifers and an understory of grasses, shrubs, Undesirable plants limit natural or artificial reforestation and forbs. unless intensive site preparation and maintenance Typically, the surface is covered with a layer of needles, measures are applied. Reforestation can be accomplished leaves, and twigs about 2 inches thick. The surface layer is by planting Douglas fir and ponderosa pine seedlings. dark brown loam about 11 inches thick. The upper 25 inches Mulching around seedlings helps to maintain the moisture of the subsoil is dark reddish brown clay loam. The lower 25 supply in summer and minimizes competition from inches is yellowish red and brown clay loam. The depth to undesirable plants. bedrock is 60 inches or more. In some areas the surface This unit is well suited to irrigated crops. It is limited layer is clay loam or gravelly loam. mainly by the slope, the hazard of erosion, and the Included in this unit are small areas of Abegg, moderately slow permeability. In summer, irrigation is Josephine, Speaker, and Wolfpeak soils; poorly drained needed for the maximum production of most crops. Because soils near drainageways and on concave slopes; and of the slope, sprinkler irrigation is the best method of Pollard soils that have slopes of less than 7 or more than applying water. This method permits an even, controlled 20 percent. Included areas make up about 20 percent of application of water, helps to prevent excessive runoff, and the total acreage. minimizes the risk of erosion. To prevent overirrigation and Permeability is slow in the Pollard soil. Available water excessive erosion, applications of irrigation water should be capacity is about 7 inches. The effective rooting depth is adjusted to the available water capacity, the rate of water 60 inches or more. Runoff is slow or medium, and the intake, and the needs of the crop. hazard of water erosion is slight or moderate. Returning all crop residue to the soil and using a This unit is used mainly for timber production, hay cropping system that includes grasses, legumes, or and pasture, or wildlife habitat. It also is used for grass-legume mixtures help to maintain fertility and tilth. homesite development. Leaving crop residue on or near the surface helps to This unit is suited to the production of Douglas fir. Other conserve moisture and control erosion. species that grow on this unit include ponderosa pine, A tillage pan forms easily if the soil is tilled when wet. sugar pine, and California black oak. The Chiseling or subsoiling breaks up the pan. Surface crusting Included in this unit are small areas of Carney soils, and compaction can be minimized by returning crop Agate and Winlo soils on the shoulders of hillslopes, and residue to the soil. soils that are similar to the Provig soil but have sandstone Seedbeds should be prepared on the contour or across bedrock at a depth of 40 to 60 inches. Also included are the slope where practical. Proper stocking rates, pasture small areas of Provig soils that have slopes of less than 15 rotation, and restricted grazing during wet periods help to or more than 35 percent. Included areas make up about 15 keep pastures in good condition and protect the soil from percent of the total acreage. erosion. Grazing when the soil is wet results in compaction Permeability is slow in the Provig soil. Available water of the surface layer, poor tilth, and excessive runoff. capacity is about 4 inches. The effective rooting depth is Periodic mowing and clipping help to maintain uniform plant 14 to 20 inches. Runoff is medium, and the hazard of growth, discourage selective grazing, and reduce the extent water erosion is moderate. of clumpy growth. Fertilizer is needed to ensure the This unit is used for livestock grazing or homesite optimum growth of grasses and legumes. Grasses respond development. to nitrogen, and legumes respond to sulfur and phosphorus. The main limitations affecting livestock grazing are The main limitations affecting homesite development compaction, the slope, the very gravelly surface layer, and are the moderately slow permeability, the shrink -swell droughtiness. The vegetation suitable for grazing includes potential, and the slope. The moderately slow permeability Idaho fescue, bluebunch wheatgrass, and pine bluegrass. If can be overcome by increasing the size of the absorption the range is overgrazed, the proportion of preferred forage field. , plants decreases and the proportion of less preferred If buildings are constructed on this unit, properly forage plants increases. Grazing should be delayed until designing foundations and footings, diverting runoff away the more desirable forage plants have achieved enough from the buildings, and backfilling with material that has a growth to withstand grazing pressure and the soil is firm low shrink -swell potential help to prevent the structural enough to withstand trampling by livestock. damage caused by shrinking and swelling. Properly Suitable management practices on this unit include designing buildings and roads helps to offset the limited proper grazing use, deferred grazing, rotation grazing, and ability of the soil to support a load. brush control. Areas that support a large amount of Erosion is a hazard on the steeper slopes. Only the competing vegetation can be improved by prescribed part of the site that is used for construction should be burning or by chemical or mechanical treatment. In places disturbed. Revegetating as soon as possible helps to the use of ground equipment is limited by the gravel and control erosion in disturbed areas around construction cobbles on the surface and by the slope. sites. Topsoil can be stockpiled and used to reclaim areas Range seeding is suitable if the site is in poor disturbed during construction. Because of a low amount of condition. The main limitations affecting seeding are rainfall in summer, irrigation is needed in areas that droughtiness and the slope. The plants selected for support lawn grasses, shrubs, vines, shade trees, or seeding should be those that meet the seasonal ornamental trees. requirements of livestock or wildlife, or both. The vegetative site is Douglas Fir-Black Oak Forest. This unit is limited as a site for livestock watering ponds and other water impoundments because of the 150E-Provig very gravelly loam, 15 to 35 percent slope. slopes. This very deep, well drained soil is on fan terrace The main limitations affecting homesite development are scarps. It formed in alluvium derived from mixed sources. the slow permeability, the slope, a high shrink-swell Elevation is 1,100 to 1,500 feet. The mean annual potential, and the very gravelly surface layer. precipitation is 18 to 30 inches, the mean annual This unit is poorly suited to standard systems of waste temperature is 52 to 54 degrees F, and the average disposal because of the slow permeability and the slope. frost-free period is 150 to 180 days. The native vegetation is Alternative waste disposal systems may function properly mainly hardwoods and an understory of grasses, shrubs, on this unit. Suitable included soils are in some areas of the and forbs. unit. Onsite investigation is needed to locate such soils. Typically, the surface layer is very dark brown and very The slope limits the use of the steeper areas of this unit dark grayish brown very gravelly loam about 9 inches thick. for building site development. Properly designing The subsoil is dark brown very gravelly clay loam about 6 foundations and footings, diverting runoff away from the inches thick. The substratum to a depth of 60 inches is buildings, and backfilling with material that has a low dark reddish brown and reddish brown, stratified extremely gravelly clay. In some areas the surface layer is very cobbly. shrink-swell potential help to prevent the structural The Agate soil is moderately deep to a hardpan and is damage caused by shrinking and swelling. well drained. It formed in alluvium derived from mixed Erosion is a hazard on the steeper slopes. Only the part sources. Typically, the surface layer is dark brown loam of the site that is used for construction should be disturbed. about 6 inches thick. The next layer is dark yellowish brown Revegetating as soon as possible helps to control erosion in clay loam about 6 inches thick. The upper 13 inches of the disturbed areas around construction sites. Establishing subsoil is dark brown clay loam. The lower 5 inches is a plants is difficult in areas where the surface layer has been hardpan. The substratum to a depth of 62 inches is light removed. Mulching and applying fertilizer help to establish olive brown extremely gravelly coarse sandy loam. Depth to plants in cut areas. Gravel and cobbles should be removed the hardpan is 20 to 30 inches. The depth to bedrock is 60 from disturbed areas, particularly areas used for lawns. inches or more. In some areas the surface layer is gravelly Topsoil can be stockpiled and used to reclaim areas or cobbly. disturbed during construction. In many areas it may be Permeability is moderately slow in the Agate soil. necessary to haul in topsoil for lawns and gardens. Because Available water capacity is about 4 inches. The effective of a low amount of rainfall in summer, irrigation is needed in rooting depth is 20 to 30 inches. Runoff is slow, and the areas that support lawn grasses, shrubs, vines, shade trees, hazard of water erosion is slight. or ornamental trees. This unit is used for hay and pasture, homesite The vegetative site is Loamy Hills, 20- to 35-inch development, and livestock grazing. precipitation zone. The main limitations affecting the use of this unit for hay and pasture are compaction, droughtiness, the limited 151C-Provig-Agate complex, 5 to 15 percent slopes. rooting depth, and the very gravelly surface layer of the This map unit is on fan terraces. Elevation is 1,100 to 1,850 Provig soil. In some areas ripping and shattering the feet. The mean annual precipitation is 18 to 30 inches, the hardpan in the Agate soil can increase the effective rooting mean annual temperature is 52 to 54 degrees F, and the depth. average frost-free period is 150 to 180 days. The native If the pasture or range is overgrazed, the proportion of vegetation on the Provig soil is mainly hardwoods and an preferred forage plants decreases and the proportion of understory of grasses, shrubs, and forbs. That on the Agate less preferred forage plants increases. The grazing system soil is mainly grasses, shrubs, and forbs. should maintain the desired balance of species in the plant This unit is about 60 percent Provig soil and 30 percent community. Proper stocking rates, pasture rotation, and Agate soil. The components of this unit occur as areas so restricted grazing during wet periods help to keep pastures intricately intermingled that mapping them separately was in good condition and protect the soils from erosion. not practical at the scale used. Grazing when the soils are wet results in compaction of the Included in this unit are small areas of Carney and Winlo surface layer, poor tilth, and excessive runoff. Periodic soils, Cove and Padigan soils near drainageways and on mowing and clipping help to maintain uniform plant growth, concave slopes, and soils that are similar to the Provig soil discourage selective grazing, and reduce the extent of but have sandstone bedrock at a depth of 40 to 60 inches. clumpy growth. Also included are small areas of Provig and Agate soils that The native vegetation suitable for grazing includes have slopes of less than 5 or more than 15 percent. Idaho fescue, bluebunch wheatgrass, pine bluegrass, Included areas make up about 10 percent of the total and Lemmon needlegrass. Areas that support a large acreage. amount of competing vegetation can be improved by The Provig soil is very deep and well drained. It formed chemical or mechanical treatment. in alluvium derived from mixed sources. Typically, the Range seeding is suitable if the site is in poor surface layer is very dark brown and very dark grayish condition. The main limitation is droughtiness. The plants brown very gravelly loam about 9 inches thick. The subsoil selected for seeding should be those that meet the is dark brown very gravelly clay loam about 6 inches thick. seasonal requirements of livestock or wildlife, or both. In The. substratum to a depth of 60 inches is dark reddish places the use of ground equipment is limited by the brown and reddish brown, stratified extremely, gravelly gravel on the surface of the Provig soil and the included clay. In some areas the surface layer is very cobbly. Winlo soils. Permeability is slow in the Provig soil. Available water In summer, irrigation is needed for the maximum capacity is about 4 inches. The effective rooting depth is production of hay and pasture. Because of the slope, 14 to 20 inches. Runoff is medium, and the hazard of sprinkler irrigation is the best method of applying water. water erosion is moderate. This method permits an even, controlled application of water, helps to prevent excessive runoff, and minimizes the risk of erosion. To prevent overirrigation and excessive erosion, applications of irrigation water should be adjusted to the available water capacity, the rate between and around areas of the Shoat soil, which is on of water intake, and the needs of the crop. Fertilizer is circular mounds (fig. 10). needed to ensure the optimum growth of grasses and Included in this unit are small areas of Lorella, Paragon, legumes. Grasses respond to nitrogen, and legumes and Skookum soils; Rock outcrop; and soils that are similar respond to sulfur and phosphorus. to the Shoat soil but have bedrock at a depth of 10 to 20 The main limitations affecting homesite development are inches or more than 40 inches. Also included are small the slow permeability, a high shrink -swell potential, the very areas of Randcore and Shoat soils that have slopes of more gravelly surface layer in the Provig soil, and depth to the than 5 percent. Included areas make up about 10 percent of hardpan in the Agate soil. the total acreage. This unit is poorly suited to standard systems of waste The Randcore soil is very shallow and moderately well disposal because of depth to the hardpan in the Agate soil drained. It formed in loess over andesite. Typically, the and the slow permeability in the Provig soil. The suitability of surface layer is dark brown extremely stony loam about 1 the Agate soil for septic tank absorption fields can be inch thick. The next layer is dark brown loam about 5 improved by ripping the hardpan. Alternative waste disposal inches thick. Bedrock is at a depth of about 6 inches. The systems may function properly on this unit. Suitable depth to bedrock ranges from 4 to 10 inches. included soils are in some areas of the unit. Onsite Permeability is moderate in the Randcore soil. investigation is needed to locate such soils. Available water capacity is about 1 inch. The effective If buildings are constructed on the Provig soil, properly rooting depth is 4 to 10 inches. This soil is ponded in designing foundations and footings, diverting runoff away January and February. Runoff is ponded, and the hazard from the buildings, and backfilling with material that has a of water erosion is slight. low shrink -swell potential help to prevent the structural The Shoat soil is moderately deep and well drained. It damage caused by shrinking and swelling. formed in loess over andesite. Typically, the surface layer Cuts needed to provide essentially level building sites is dark brown loam about 4 inches thick. The subsoil also can expose bedrock. Establishing plants is difficult in areas is dark brown loam. It is about 20 inches thick. Bedrock is where the surface layer has been removed. Mulching and at a depth of about 24 inches. The depth to bedrock applying fertilizer help to establish plants in cut areas. ranges from 20 to 40 inches, In some areas the surface Gravel and cobbles should be removed from disturbed layer is stony. areas, particularly areas used for lawns. Topsoil can be Permeability is moderate in the Shoat soil. Available stockpiled and used to reclaim areas disturbed during water capacity is about 5 inches. The effective rooting depth construction. In many areas it may be necessary to haul in is 20 to 40 inches. Runoff is slow, and the hazard of water topsoil for lawns and gardens. Because of a low amount of erosion is slight. rainfall in summer, irrigation is needed in areas that support This unit is used for livestock grazing and wildlife habitat. lawn grasses, shrubs, vines, shade trees, or ornamental The main limitations affecting livestock grazing are trees. compaction and droughtiness in summer and fall. The The vegetative site in areas of the Provig soil is Loamy Randcore soil also is limited by stones on the surface, Hills, 20- to 35-inch precipitation zone, and the one in wetness in winter and spring, and the depth to bedrock. areas of the Agate soil is Biscuit-Scabland (mound), 18- The vegetation suitable for grazing includes bluebunch to 26-inch precipitation zone. wheatgrass, Idaho fescue, and pine bluegrass. If the range is overgrazed, the proportion of preferred forage plants 152B-Randcore -Shoat complex, 0 to 5 percent decreases and the proportion of less preferred forage slopes. This map unit is on plateaus. Elevation is 2,000 to plants increases. Grazing should be delayed until the more 3,800 feet. The mean annual precipitation is 18 to 25 desirable forage plants have achieved enough growth to inches, the mean annual temperature is 45 to 52 degrees withstand grazing pressure and the soils are firm enough to F, and the average frost-free period is 100 to 150 days. The withstand trampling by livestock. native vegetation is mainly grasses, shrubs, and forbs. Suitable management practices on this unit include This unit is about 60 percent Randcore soil and 30 proper grazing use, deferred grazing, rotation grazing, and percent Shoat soil. The components of this unit occur as brush control. Areas that support a large amount of areas so intricately intermingled that mapping them competing vegetation can be improved by chemical or separately was not practical at the scale used. The soils mechanical treatment. The use of ground equipment occur as patterned land. Areas of the Randcore soil are generally is not practical because of the stones on the surface of the Randcore soil. This unit is poorly suited to range seeding. The main Figure 10.-An area of Randcore-Shoat complex, 0 to 5 percent slopes, which occurs as patterned land.

limitations in areas of the Randcore soil are the depth to 153B-Reinecke -Coyata complex, 0 to 5 percent bedrock, the stones on the surface, wetness in winter and slopes. This map unit is on plateaus. Elevation is 2,600 to spring, and droughtiness in summer and fall. The main 3,800 feet. The mean annual precipitation is 40 to 50 limitation affecting seeding on the Shoat soil is inches, the mean annual temperature is 45 to 50 degrees F, droughtiness. The plants selected for seeding should be and the average frost-free period is 100 to 150 days. The those that meet the seasonal requirements of livestock or native vegetation is mainly conifers and an understory of wildlife, or both. grasses, shrubs, and forbs. This unit is limited as a site for livestock watering This unit is about 55 percent Reinecke soil and 30 ponds and other water impoundments because of the percent Coyata soil. The components of this unit occur as depth to bedrock. areas so intricately intermingled that mapping them The vegetative site in areas of the Randcore soil is separately was not practical at the scale used. The Coyata Biscuit-Scabland (intermound), 18- to 26-inch soil commonly is on the more sloping parts of the precipitation zone, and the one in areas of the Shoat soil landscape. is Biscuit-Scabland (mound), 18- to 26-inch precipitation Included in this unit are small areas of Alcot, Crater zone. Lake, and Dumont soils; soils that are similar to the Reinecke soil but are overlain by less than 20 inches of ash; stand of trees at 60 years and 58,200 board feet per acre and soils that are similar to the Coyata soil but have bedrock (Scribner rule) at 120 years. On the basis of a 50-year at a depth of more than 40 inches. Also included are small curve, the mean site index is 100. areas of Reinecke and Coyata soils that have slopes of The main limitations affecting timber production are more than 5 percent. Included areas make up about 15 compaction, plant competition, and seedling mortality. percent of the total acreage. Conventional methods of harvesting timber generally are The Reinecke soil is very deep and well drained. It suitable, but the soils may be compacted if they are moist formed in volcanic ash over residuum derived dominantly when heavy equipment is used. Because of the high content from andesite. Typically, the surface is covered with a layer of volcanic ash in the Reinecke soil, displacement of the of needles and twigs about 2 inches thick. The surface layer surface layer occurs most readily during dry periods. is dark brown sandy loam about 9 inches thick. The subsoil Puddling can occur when the soils are wet. Using is brown gravelly sandy loam about 16 inches thick. It is low-pressure ground equipment causes less damage to the underlain by a buried soil. The upper 8 inches of the buried soils and helps to maintain productivity. Compaction can be soil is dark reddish brown loam. The lower 27 inches is dark minimized by using suitable methods of harvesting, laying reddish brown cobbly loam. The depth to bedrock is 60 out skid trails in advance, and harvesting timber when the inches or more. soils are least susceptible to compaction. Ripping skid trails Permeability is moderate in the Reinecke soil. and landings when the soils are dry can improve the, growth Available water capacity is about 12 inches. The effective of plants. rooting depth is 60 inches or more. Runoff is slow, and Logging roads require suitable surfacing for year-round the hazard of water erosion is slight. use. Construction and maintenance of roads built on the The Coyata soil is moderately deep and well drained. It Reinecke soil may be difficult because of the volcanic ash, formed in colluvium derived dominantly from andesite. which is poor surged material because it is not easily Typically, the surface is covered with a layer of needles, compacted when dry, has a moderate potential for frost leaves, and twigs about 1 1/2 inches thick. The surface layer action, and has a high water-holding capacity. When wet or is dark reddish brown gravelly loam about 11 inches thick. moist, unsurfaced roads and skid trails are soft. They may The next layer is dark brown very cobbly clay loam about 10 be impassable during rainy periods. When dry, they are very inches thick. The subsoil is dark brown extremely cobbly dusty. clay loam about 10 inches thick. Bedrock is at a depth of Erosion can be controlled by carefully planning the about 31 inches. The depth to bedrock ranges from 20 to 40 construction and maintenance of logging roads, skid trails, inches. In some areas the surface layer is cobbly or stony. and landings. Seeding, mulching, and benching areas that Permeability is moderate in the Coyata soil. Available have been cut and filled also help to control erosion. water capacity is about 2 inches. The effective rooting depth Undesirable plants limit natural or artificial reforestation is 20 to 40 inches. Runoff is slow, and the hazard of water unless intensive site preparation and maintenance erosion is slight. measures are applied. Reforestation can be accomplished This unit is used for timber production, livestock by planting Douglas fir and ponderosa pine seedlings. grazing, and wildlife habitat. Mulching around seedlings helps to maintain the moisture This unit is suited to the production of Douglas fir. Other supply in summer and minimizes competition from species that grow on this unit include white fir, western undesirable plants. hemlock, and golden chinkapin. The understory vegetation Severe frost can damage or kill seedlings. Air drainage includes vine maple, California hazel, and cascade may be restricted on this unit. Proper timber harvesting Oregongrape. methods can reduce the effect of frost on regeneration. On the basis of a 100-year site curve, the mean site The main limitation affecting livestock grazing is index for Douglas fir is 145 on the Reinecke soil. The yield compaction. The Reinecke soil also is limited by soil at culmination of the mean annual increment is 9,120 cubic displacement. The native vegetation suitable for grazing feet per acre in a fully stocked, even-aged stand of trees at includes western fescue, mountain brome, and Alaska 60 years and 74,360 board feet per acre (Scribner rule) at oniongrass. If the understory is overgrazed, the proportion 110 years. On the basis of a 50-year curve, the mean site of preferred forage plants decreases and the proportion of index is 110. less preferred forage plants increases. On the basis of a 100-year site curve, the mean site A planned grazing system that includes timely deferment index for Douglas fir is 130 on the Coyata soil. The yield at of grazing, rotation grazing, and proper livestock distribution culmination of the mean annual increment is 7,740 cubic helps to prevent overgrazing of the feet per acre in a fully stocked, even-aged understory and damage to the soils. Grazing should be frost-free period is less than 100 days. The native delayed until the more desirable forage plants have vegetation is mainly conifers and an understory of achieved enough growth to withstand grazing pressure and grasses, shrubs, and forbs. the soils are firm enough to withstand trampling by Typically, the surface layer is very dark grayish brown livestock. Displacement of the surface layer occurs most cobbly coarse sandy loam about 6 inches thick. The subsoil readily when the soils are dry. is brown and yellowish brown cobbly coarse sandy loam Thinning, logging, and fire reduce the density of the about 28 inches thick. The substratum is light olive brown overstory canopy and increase the production of understory and light yellowish brown coarse sandy loam about 20 vegetation. Areas that support a large amount of competing inches thick. Weathered bedrock is at a depth of about 54 vegetation can be improved by prescribed burning or by inches. The depth to bedrock ranges from 40 to 60 inches. chemical or mechanical treatment. Seeding disturbed areas In some areas the surface layer is stony or very cobbly. to suitable plants increases forage production and reduces Included in this unit are small areas of poorly drained the risk of erosion. The seedling mortality rate may be soils near drainageways and on concave slopes and soils increased if the Reinecke soil is grazed when it is that are similar to the Rogue soil but have more than 35 susceptible to displacement. percent rock fragments or have bedrock at a depth of less The vegetative site is Mixed Fir-Western Hemlock than 40 or more than 60 inches. Also included are small Forest. areas of Rogue soils that have slopes of less than 12 or more than 35 percent. Included areas make up about 20 154-Riverwash. This map unit consists of deep, percent of the total acreage. excessively drained to very poorly drained, recently Permeability is moderately rapid in the Rogue soil. deposited alluvium in narrow, irregular strips along the major Available water capacity is about 4 inches. The effective streams and rivers. Slope is 0 to 3 percent. Riverwash rooting depth is 40 to 60 inches. Runoff is medium, and the supports little, if any, vegetation. Elevation is 1,000 to 2,000 hazard of water erosion is high. feet. The mean annual precipitation is 18 to 40 inches, the This unit is used for timber production, livestock mean annual temperature is 48 to 54 degrees F, and the grazing, and wildlife habitat. average frost-free period is 140 to 180 days. This unit is suited to the production of white fir. Other Most areas of Riverwash are very cobbly, extremely species that grow on this unit include Douglas fir, incense cobbly, or extremely gravelly sand to a depth of 60 inches cedar, and ponderosa pine. The understory vegetation or more. includes creambush oceanspray, cascade Oregongrape, Included in this unit are small areas of Camas, Evans, and whitevein shinleaf. and Newberg soils on flood plains and Takilma soils on On the basis of a 50-year site curve, the mean site terraces. Also included are small areas of Dumps and index for white fir is 80. The yield at culmination of the Xerorthents. mean annual increment is 13,720 cubic feet per acre in a Permeability is very rapid in the areas of Riverwash. fully stocked, even-aged stand of trees at 70 years. Available water capacity is low. Runoff is slow, and the The main limitations affecting timber production are hazard of water erosion is slight to severe. This unit is erosion, compaction, plant competition, and seedling subject to flooding during prolonged, high-intensity storms. mortality. When timber is harvested, management that Channeling and deposition are common along minimizes the risk of erosion is essential. Wheeled and streambanks. tracked logging equipment can be used in the less sloping This unit is used mainly for wildlife habitat. A few areas areas, but cable yarding generally is safer in the more are used as a source of sand and gravel. Because it is sloping areas and results in less surface disturbance. If the frequently flooded, the unit is unsuited to most other uses. soil is excessively disturbed when timber is harvested or This unit is not assigned to a vegetative site. logging roads are built, a larger number of rock fragments is left on the surface. Using standard wheeled and tracked 155E-Rogue cobbly coarse sandy loam, 12 to 35 equipment when the soil is moist causes rutting and percent north slopes. This deep, somewhat excessively compaction. Puddling can occur when the soil is wet. Using drained soil is on hillslopes. It formed in colluvium derived low-pressure ground equipment causes less damage to the dominantly from granitic rock. Elevation is 3,600 to 6,000 soil and helps to maintain productivity. Compaction can be feet. The mean annual precipitation is 35 to 55 inches, the minimized by using suitable methods of harvesting, laying mean annual temperature is 40 to 45 degrees F, and the out skid trails in advance, and harvesting timber when the average soil is least susceptible to compaction. Ripping skid trails and landings when the soil is dry can improve the growth of Thinning, logging, and fire reduce the density of the plants. overstory canopy and increase the production of Properly designed road drainage systems that include understory vegetation. Areas that support a large amount carefully located culverts help to control erosion. Areas that of competing vegetation can be improved by prescribed have been cut and filled are easily eroded unless they are burning or by chemical or mechanical treatment. Seeding treated. Seeding, mulching, and benching these areas help disturbed areas to suitable plants increases forage to control erosion. Steep yarding paths, skid trails, and production and reduces the risk of erosion. firebreaks are subject to rilling and gullying unless they are The vegetative site is Mixed Fir-Oceanspray Forest. protected by a plant cover or adequate water bars, or both. Cutbanks occasionally slump when the soil is saturated. 155G-Rogue cobbly coarse sandy loam, 35 to 80 This unit is subject to slumping, especially in areas percent north slopes. This deep, somewhat excessively adjacent to drainageways. Road failure and landslides are drained soil is on hillslopes. It formed in colluvium derived likely to occur after road construction and clearcutting. Skid dominantly from granitic rock. Elevation is 3,600 to 6,000 trails and unsurfaced roads may be impassable during feet. The mean annual precipitation is 35 to 55 inches, the rainy periods. Logging roads require suitable surfacing for mean annual temperature is 40 to 45 degrees F, and the year-round use. average frost-free period is less than 100 days. The native Undesirable plants limit natural or artificial reforestation vegetation is mainly conifers and an understory of unless intensive site preparation and maintenance grasses, shrubs, and forbs. measures are applied. Reforestation can be accomplished Typically, the surface layer is very dark grayish brown by planting Douglas fir and white fir seedlings. Mulching cobbly coarse sandy loam about 6 inches thick. The around seedlings helps to maintain the moisture supply in subsoil is brown and yellowish brown cobbly coarse sandy summer and minimizes competition from undesirable loam about 28 inches thick. The substratum is light olive plants. brown and light yellowish brown coarse sandy loam about A high temperature in the surface layer during summer 20 inches thick. Weathered bedrock is at a depth of about and the low available water capacity increase the seedling 54 inches. The depth to bedrock range; from 40 to 60 mortality rate. The large number of rock fragments in the inches. In some areas the surface layer stony or very soil also increases the seedling mortality rate. To cobbly. compensate for the expected high mortality rate, the larger Included in this unit are small areas of poorly drained seedlings or a greater number of seedlings should be soils near drainageways and soils that are similar to the planted. When the timber is harvested, leaving some of the Rogue soil but have more than 35 percent rock fragments larger trees unharvested provides shade for seedlings. or have bedrock at a depth of less than 40 c more than 60 Severe frost can damage or kill seedlings. In the less inches. Also included are small areas of Rogue soils that sloping areas where air drainage may be restricted, proper have slopes of less than 35 or more than 80 percent. timber harvesting methods can reduce the effect of frost on Included areas make up about 20 percent of the total regeneration. acreage. Increased erosion, loss of plant nutrients, and water Permeability is moderately rapid in the Rogue soil. repellency are likely to result from fires of moderate Available water capacity is about 4 inches. The effective intensity. rooting depth is 40 to 60 inches. Runoff is rapid, and the The main limitations affecting livestock grazing are hazard of water erosion is high. compaction and erosion. The native vegetation suitable for This unit is used for timber production, livestock grazing includes western fescue, mountain brome, and grazing, and wildlife habitat. Alaska oniongrass. If the understory is overgrazed, the This unit is suited to the production of white fir. Other proportion of preferred forage plants decreases and the species that grow on this unit include Douglas fir, incense proportion of less preferred forage plants increases. cedar, and ponderosa pine. The understory vegetation A planned grazing system that includes timely deferment includes creambush oceanspray, cascade Oregongrape, of grazing, rotation grazing, and proper livestock distribution and whitevein shinleaf. helps to prevent overgrazing of the understory and damage On the basis of a 50-year site curve, the mean site to the soil. Grazing should be delayed until the more index for white fir is 80. The yield at culmination of the desirable forage plants have achieved enough growth to mean annual increment is 13,720 cubic feet per acre in a withstand grazing pressure and the soil is firm enough to fully stocked, even-aged stand of trees at 70 years. withstand trampling by livestock. The main limitations affecting timber production are the slope, erosion, compaction, plant competition, and seedling mortality. When timber is harvested, management mortality rate. To compensate for the expected high that minimizes the risk of erosion is essential. Wheeled and mortality rate, the larger seedlings or a greater number of tracked logging equipment can be used in the less sloping seedlings should be planted. When the timber is harvested, areas, but cable yarding generally is safer and results in leaving some of the larger trees unharvested provides less surface disturbance. If the soil is excessively disturbed shade for seedlings. when timber is harvested or logging roads are built, a larger Severe frost can damage or kill seedlings. Proper timber number of rock fragments is left on the surface. Using harvesting methods can reduce the effect of frost on standard wheeled and tracked equipment when the soil is regeneration. moist causes rutting and compaction. Puddling can occur Increased erosion, loss of plant nutrients, and water when the soil is wet. Using low-pressure ground equipment repellency are likely to result from fires of moderate causes less damage to the soil and helps to maintain intensity. productivity. Compaction can be minimized by using The main limitations affecting livestock grazing are suitable methods of harvesting, laying out skid trails in erosion, compaction, and the slope. The native vegetation advance, and harvesting timber when the soil is least suitable for grazing includes western fescue, mountain susceptible to compaction. Ripping skid trails and landings brome, and Alaska oniongrass. when the soil is dry can improve the growth of plants. A planned grazing system that includes timely deferment Properly designed road drainage systems that include of grazing, rotation grazing, and proper livestock distribution carefully located culverts help to control erosion. Areas that helps to prevent overgrazing of the understory and damage have been cut and filled are easily eroded unless they are to the soil. Grazing should be delayed until the more treated. Seeding, mulching, and benching these areas help desirable forage plants have achieved enough growth to to control erosion. Steep yarding paths, skid trails, and withstand grazing pressure and the soil is firm enough to firebreaks are subject to rilling and gullying unless they are withstand trampling by livestock. protected by a plant cover or adequate water bars, or both. Thinning, logging, and fire reduce the density of the Cutbanks occasionally slump when the soil is saturated. overstory canopy and increase the production of This unit is subject to slumping, especially in areas understory vegetation. Areas that support a large amount adjacent to drainageways. Road failure and landslides are of competing vegetation can be improved by prescribed likely to occur after road construction and clearcutting. Skid burning or by chemical or mechanical treatment. Seeding trails and unsurfaced roads may be impassable during disturbed areas to suitable plants increases forage rainy periods. Logging roads require suitable surfacing for production and reduces the risk of erosion. year-round use. The vegetative site is Mixed Fir-Oceanspray Forest. Constructing logging roads on the steeper slopes can result in a high risk of erosion. Building logging roads at 156E-Rogue cobbly coarse sandy loam, 12 to 35 midslope requires extensive cutting and filling and removes percent south slopes. This deep, somewhat excessively land from production. Material that is discarded when the drained soil is on hillslopes. It formed in colluvium derived roads are built can damage vegetation and is a potential dominantly from granitic rock. Elevation is 3,600 to 6,000 source of sedimentation. If the material becomes saturated, feet. The mean, annual precipitation is 35 to 55 inches, the avalanches of debris can occur. End hauling of the waste mean annual temperature is 40 to 45 degrees F, and the material minimizes damage to the vegetation downslope average frost-free period is less than 100 days. The native and reduces the risk of sedimentation. vegetation is mainly conifers and an understory of grasses, Undesirable plants limit natural or artificial reforestation shrubs, and forbs. unless intensive site preparation and maintenance Typically, the surface layer is very dark grayish brown measures are applied. Reforestation can be accomplished cobbly coarse sandy loam about 6 inches thick. The subsoil by planting Douglas fir and white fir seedlings. Mulching is brown and yellowish brown cobbly coarse sandy loam around seedlings helps to maintain the moisture supply in about 28 inches thick. The substratum is light olive brown summer and minimizes competition from undesirable and light yellowish brown coarse sandy loam about 20 plants. inches thick. Weathered bedrock is at a depth of about 54 A high temperature in the surface layer during summer inches. The depth to bedrock ranges from 40 to 60 inches. In and the low available water capacity increase the some areas the surface layer is stony or very cobbly. seedling mortality rate. The large number of rock Included in this unit are small areas of poorly drained fragments in the soil also increases the seedling soils near drainageways and on concave slopes and soils that are similar to the Rogue soil but have more yarding paths, skid trails, and firebreaks are subject to than 35 percent rock fragments or have bedrock at a rilling and gullying unless they are protected by a plant depth of less than 40 or more than 60 inches. Also cover or adequate water bars, or both. Cutbanks included are small areas of Rogue soils that have slopes occasionally slump when the soil is saturated. of less than 12 or more than 35 percent. Included areas This unit is subject to slumping, especially in areas make up about 20 percent of the total acreage. adjacent to drainageways. Road failure and landslides are Permeability is moderately rapid in the Rogue soil. likely to occur after road construction and clearcutting. Skid Available water capacity is about 4 inches. The effective trails and unsurfaced roads may be impassable during rooting depth is 40 to 60 inches. Runoff is medium, and the rainy periods. Logging roads require suitable surfacing for hazard of water erosion is high. year-round use. This unit is used for timber production, livestock A high temperature in the surface layer during summer grazing, and wildlife habitat. and the low available water capacity increase the seedling This unit is suited to the production of white fir and mortality rate. The large number of rock fragments in the soil Douglas fir. Other species that grow on this unit include also increases the seedling mortality rate. To compensate incense cedar and ponderosa pine. The understory for the expected high mortality rate, the larger seedlings or a vegetation includes Pacific serviceberry, tall Oregongrape, greater number of seedlings should be planted. When the and common snowberry. timber is harvested, leaving some of the larger trees On the basis of a 50-year site curve, the mean site unharvested provides shade for seedlings. The seedling index for white fir is 70. The yield at culmination of the mortality rate also can be reduced by providing artificial mean annual increment is 11,410 cubic feet per acre in a shade for seedlings. Reforestation can be accomplished by fully stocked, even-aged stand of trees at 70 years. planting Douglas fir and ponderosa pine seedlings. On the basis of a 100-year site curve, the mean site Severe frost can damage or kill seedlings. In the less index for Douglas fir is 100. The yield at culmination of the sloping areas where air drainage may be restricted, proper mean annual increment is 5,040 cubic feet per acre in a timber harvesting methods can reduce the effect of frost on fully stocked, even-aged stand of trees at 60 years and regeneration. 39,750 board feet per acre (Scribner rule) at 150 years. On Undesirable plants limit natural or artificial the basis of a 50-year curve, the mean site index is 70. reforestation unless intensive site preparation and The main limitations affecting timber production are maintenance measures are applied. Mulching around erosion, compaction, seedling mortality, and plant seedlings helps to maintain the moisture supply in competition. When timber is harvested, management that summer and minimizes competition from undesirable minimizes the risk of erosion is essential. Wheeled and plants. tracked logging equipment can be used in the less sloping Increased erosion, loss of plant nutrients, and water areas, but cable yarding generally is safer in the more repellency are likely to result from fires of moderate sloping areas and results in less surface disturbance. If the intensity. soil is excessively disturbed when timber is harvested or The main limitations affecting livestock grazing are logging roads are built, a larger number of rock fragments is compaction and erosion. The native vegetation suitable for left on the surface. grazing includes western fescue, mountain brome, tall Using standard wheeled and tracked equipment when trisetum, and Alaska oniongrass. If the understory is the soil is moist causes rutting and compaction. Puddling overgrazed, the proportion of preferred forage plants can occur when the soil is wet. Using low-pressure ground decreases and the proportion of less preferred forage plants equipment causes less damage to the soil and helps to increases. maintain productivity. Compaction can be minimized by A planned grazing system that includes timely deferment using suitable methods of harvesting, laying out skid trails of grazing, rotation grazing, and proper livestock distribution in advance, and harvesting timber when the soil is least helps to prevent overgrazing of the understory and damage susceptible to compaction. Ripping skid trails and landings to the soil. Grazing should be delayed until the more when the soil is dry can improve the growth of plants. desirable forage plants have achieved enough growth to Properly designed road drainage systems that include withstand grazing pressure and the soil is firm enough to carefully located culverts help to control erosion. Areas that withstand trampling by livestock. have been cut and filled are easily eroded unless they are Thinning, logging, and fire reduce the density of the treated. Seeding, mulching, and benching these areas help overstory canopy and increase the production of to control erosion. Steep understory vegetation. Areas that support a large amount of competing vegetation can be improved by prescribed burning or by chemical or mechanical years. On the basis of a 50-year curve, the mean site treatment. Seeding disturbed areas to suitable plants index is 70. increases forage production and reduces the risk of The main limitations affecting timber production are the erosion. slope, erosion, compaction, seedling mortality, and plant The vegetative site is Mixed Fir-Serviceberry Forest. competition. When timber is harvested, management that minimizes the risk of erosion is essential. Wheeled and 156G-Rogue cobbly coarse sandy loam, 35 to 75 tracked logging equipment can be used in the less sloping percent south slopes. This deep, somewhat excessively areas, but cable yarding generally is safer and results in drained soil is on hillslopes. It formed in colluvium derived less surface disturbance. If the soil is excessively disturbed dominantly from granitic rock. Elevation is 3,600 to 6,000 when timber is harvested or logging roads are built, a feet. The mean annual precipitation is 35 to 55 inches, the larger number of rock fragments is left on the surface. mean annual temperature is 40 to 45 degrees F, and the Using standard wheeled and tracked equipment when average frost-free period is less than 100 days. The native the soil is moist causes rutting and compaction. Puddling vegetation is mainly conifers and an understory of grasses, can occur when the soil is wet. Using low-pressure ground shrubs, and forbs. equipment causes less damage to the soil and helps to Typically, the surface layer is very dark grayish brown maintain productivity. Compaction can be minimized by cobbly coarse sandy loam about 6 inches thick. The subsoil using suitable methods of harvesting, laying out skid trails is brown and yellowish brown cobbly coarse sandy loam in advance, and harvesting timber when the soil is least about 28 inches thick. The substratum is light olive brown susceptible to compaction. Ripping skid trails and landings and light yellowish brown coarse sandy loam about 20 when the soil is dry can improve the growth of plants. inches thick. Weathered bedrock is at a depth of about 54 Properly designed road drainage systems that include inches. The depth to bedrock ranges from 40 to 60 inches. carefully located culverts help to control erosion. Areas that In some areas the surface layer is stony or very cobbly. have been cut and filled are easily eroded unless they are Included in this unit are small areas of poorly drained treated. Seeding, mulching, and benching these areas help soils near drainageways and soils that are similar to the to control erosion. Steep yarding paths, skid trails, and Rogue soil but have more than 35 percent rock fragments or firebreaks are subject to rilling and gullying unless they are have bedrock at a depth of less than 40 or more than 60 protected by a plant cover or adequate water bars, or both. inches. Also included are small areas of Rogue soils that Cutbanks occasionally slump when the soil is saturated. have slopes of less than 35 or more than 75 percent. This unit is subject to slumping, especially in areas Included areas make up about 20 percent of the total adjacent to drainageways. Road failure and landslides are acreage. likely to occur after road construction and clearcutting. Skid Permeability is moderately rapid in the Rogue soil. trails and unsurfaced roads may be impassable during Available water capacity is about 4 inches. The effective rainy periods. Logging roads require suitable surfacing for rooting depth is 40 to 60 inches. Runoff is rapid, and the year-round use. hazard of water erosion is high. Constructing logging roads on the steeper slopes can This unit is used for timber production, livestock result in a high risk of erosion. Building logging roads at grazing, and wildlife habitat. midslope requires extensive cutting and filling and removes This unit is suited to the production of white fir and land from production. Material that is discarded when the Douglas fir. Other species that grow on this unit include roads are built can damage vegetation and is a potential incense cedar and ponderosa pine. The understory source of sedimentation. If the material becomes saturated, vegetation includes Pacific serviceberry, tall Oregongrape, avalanches of debris can occur. End hauling of the waste and common snowberry. material minimizes damage to the vegetation downslope On the basis of a 50-year site curve, the mean site index and reduces the risk of sedimentation. for white fir is 70. The yield at culmination of the mean A high temperature in the surface layer during summer annual increment is 11,410 cubic feet per acre in a fully and the low available water capacity increase the seedling stocked, even-aged stand of trees at 70 years. mortality rate. The large number of rock fragments in the On the basis of a 100-year site curve, the mean site soil also increases the seedling mortality rate. To index for Douglas fir is 100. The yield at culmination of the compensate for the expected high mortality rate, the larger mean annual increment is 5,040 cubic feet per acre in a seedlings or a greater number of seedlings should be fully stocked, even-aged stand of trees at 60 years and planted. When the timber is 39,750 board feet per acre (Scribner rule) at 150 harvested, leaving some of the larger trees unharvested red loam. The depth to bedrock is 60 inches or more. In provides shade for seedlings. The seedling mortality rate some areas the surface layer is gravelly, cobbly, or stony. also can be reduced by providing artificial shade for Included in this unit are small areas of Camas, Evans, seedlings. Reforestation can be accomplished by planting and Newberg soils on flood plains; Gregory soils near Douglas fir and ponderosa pine seedlings. drainageways; Selmac soils on concave slopes; Coleman, Severe frost can damage or kill seedlings. Proper timber Foehlin, and Medford soils on terraces; and Abegg, Manita, harvesting methods can reduce the effect of frost on Shefflein, and Vannoy soils. Also included are small areas regeneration. of Xerorthents, small areas of Dumps, and small areas of Undesirable plants limit natural or artificial Ruch soils that have slopes of more than 7 percent. reforestation unless intensive site preparation and Included areas make up about 20 percent of the total maintenance measures are applied. Mulching around acreage. seedlings helps to maintain the moisture supply in Permeability is moderately slow in the Ruch soil. summer and minimizes competition from undesirable Available water capacity is about 8 inches. The effective plants. rooting depth is 60 inches or more. Runoff is slow, and the Increased erosion, loss of plant nutrients, and water hazard of water erosion is slight. repellency are likely to result from fires of moderate This unit is used for irrigated crops, such as alfalfa hay, intensity. small grain, and tree fruit. Other crops include corn for The main limitations affecting livestock grazing are silage and grass-legume hay. Some areas are used for erosion, compaction, and the slope. The native vegetation timber production, pasture, or homesite development. suitable for grazing includes western fescue, mountain This unit is well suited to irrigated crops. It is limited brome, tall trisetum, and Alaska oniongrass. If the mainly by the moderately slow permeability. In summer, understory is overgrazed, the proportion of preferred forage irrigation is needed for the maximum production of most plants decreases and the proportion of less preferred forage crops. Furrow, border, corrugation, trickle, and sprinkler plants increases. irrigation systems are suitable. The system used generally A planned grazing system that includes timely deferment is governed by the crop that is grown. For the efficient of grazing, rotation grazing, and proper livestock distribution application and removal of surface irrigation water, land helps to prevent overgrazing of the understory and damage leveling is needed. To prevent overirrigation and excessive to the soil. Grazing should be delayed until the more erosion, applications of irrigation water should be adjusted desirable forage plants have achieved enough growth to to the available water capacity, the rate of water intake, and withstand grazing pressure and the soil is firm enough to the needs of the crop. The use of pipe, ditch lining, or drop withstand trampling by livestock. structures in irrigation ditches reduces water loss and the Thinning, logging, and fire reduce the density of the hazard of erosion. overstory canopy and increase the production of Returning all crop residue to the soil and using a understory vegetation. Areas that support a large amount cropping system that includes grasses, legumes, or of competing vegetation can be improved by prescribed grass-legume mixtures help to maintain fertility and tilth. burning or by chemical or mechanical treatment. Seeding Leaving crop residue on or near the surface helps to disturbed areas to suitable plants increases forage conserve moisture and control erosion. production and reduces the risk of erosion. A tillage pan forms easily if the soil is tilled when wet. The vegetative site is Mixed Fir-Serviceberry Forest. Chiseling or subsoiling breaks up the pan. Surface crusting and compaction can be minimized by returning crop residue 157B-Ruch silt loam, 2 to 7 percent slopes. This very to the soil. deep, well drained soil is on alluvial fans. It formed in Proper stocking rates, pasture rotation, and restricted alluvium derived dominantly from metamorphic rock. grazing during wet periods help to keep pastures in good Elevation is 1,000 to 3,000 feet. The mean annual condition and protect the soil from erosion. Grazing when precipitation is 20 to 35 inches, the mean annual the soil is wet results in compaction of the surface layer, temperature is 50 to 54 degrees F, and the average poor tilth, and excessive runoff. Periodic mowing and frost-free period is 140 to 180 days. The native vegetation clipping help to maintain uniform plant growth, discourage is mainly conifers and hardwoods and an understory of selective grazing, and reduce the extent of clumpy growth. grasses, shrubs, and forbs. Fertilizer is needed to ensure the optimum growth of Typically, the surface layer is dark brown silt loam about grasses and legumes. Grasses respond to nitrogen, and 7 inches thick. The upper 10 inches of the subsoil is reddish legumes respond to sulfur and phosphorus. brown loam. The lower 53 inches is yellowish Solid-set sprinkler irrigation is the best method of number of seedlings should be planted. When the timber is controlling frost and providing adequate moisture for tree harvested, leaving some of the larger trees unharvested fruit. Compaction can be minimized by limiting the use of provides shade for seedlings. Reforestation can be equipment when the soil is wet. A permanent cover crop accomplished by planting Douglas fir and ponderosa pine helps to control runoff and erosion. seedlings. This unit is well suited to homesite development. It has Undesirable plants limit natural or artificial few limitations. Revegetating as soon as possible in reforestation unless intensive site preparation and disturbed areas around construction sites helps to control maintenance measures are applied. Mulching around erosion. Topsoil can be stockpiled and used to reclaim seedlings helps to maintain the moisture supply in areas disturbed during construction. In summer, irrigation is summer and minimizes competition from undesirable needed in areas that support lawn grasses, shrubs, vines, plants. shade trees, or ornamental trees. The vegetative site is Douglas Fir-Mixed Pine-Fescue This unit is suited to the production of ponderosa pine Forest. and Douglas fir. Other species that grow on this unit include incense cedar, sugar pine, and Pacific madrone. 158B-Ruch gravelly silt loam, 2 to 7 percent slopes. The understory vegetation includes deerbrush, tall This very deep, well drained soil is on alluvial fans. It formed Oregongrape, and western fescue. in alluvium derived dominantly from metamorphic rock. On the basis of a 100-year site curve, the mean site Elevation is 1,000 to 3,000 feet. The mean annual index for ponderosa pine is 115. The yield at culmination precipitation is 20 to 35 inches, the mean annual of the mean annual increment is 5,280 cubic feet per acre temperature is 50 to 54 degrees F, and the average in a fully stocked, even-aged stand of trees at 40 years frost-free period is 140 to 180 days. The native vegetation is and 56,780 board feet per acre (Scribner rule) at 110 mainly conifers and hardwoods and an understory of years. grasses, shrubs, and forbs. On the basis of a 100-year site curve, the mean site Typically, the surface layer is dark brown gravelly silt index for Douglas fir is 90. The yield at culmination of the loam about 7 inches thick. The upper 10 inches of the mean annual increment is 4,200 cubic feet per acre in a subsoil is reddish brown loam. The lower 53 inches is fully stocked, even-aged stand of trees at 60 years and yellowish red loam. The depth to bedrock is 60 inches or 31,840 board feet per acre (Scribner rule) at 160 years. On more. In some areas the surface layer is cobbly or stony. the basis of a 50-year curve, the mean site index is 70. Included in this unit are small areas of Camas, Evans, The main limitations affecting timber production are and Newberg soils on flood plains; Gregory soils near compaction, seedling mortality, and plant competition. drainageways; Selmac soils on concave slopes; Coleman, Conventional methods of harvesting timber generally are Foehlin, and Medford soils on terraces; and Abegg, Manita, suitable, but the soil may be compacted if it is moist when Shefflein, and Vannoy soils. Also included are small areas heavy equipment is used. Puddling can occur when the soil of Xerorthents, small areas of Dumps, and small areas of is wet. Using low-pressure ground equipment causes less Ruch soils that have slopes of more than 7 percent. damage to the soil and helps to maintain productivity. Included areas make up about 20 percent of the total Compaction can be minimized by using suitable methods of acreage. harvesting, laying out skid trails in advance, and harvesting Permeability is moderately slow in the Ruch soil. timber when the soil is least susceptible to compaction. Available water capacity is about 8 inches. The effective Ripping skid trails and landings when the soil is dry can rooting depth is 60 inches or more. Runoff is slow, and the improve the growth of plants. hazard of water erosion is slight. Erosion can be controlled by carefully planning the This unit is used for irrigated crops, such as alfalfa hay, construction and maintenance of logging roads, skid trails, small grain, and tree fruit. Other crops include corn for and landings. Seeding, mulching, and benching areas that silage and grass-legume hay. Some areas are used for have been cut and filled also help to control erosion. Skid timber production, pasture, or homesite development. trails and unsurfaced roads may be impassable during This unit is well suited to irrigated crops. It is limited rainy periods. Logging roads require suitable surfacing for mainly by the moderately slow permeability and the gravelly year-round use. surface layer, which may limit the use of some equipment A high temperature in the surface layer and an and increase maintenance costs. In summer, irrigation is insufficient moisture supply in summer increase the needed for the maximum production of most crops. Furrow, seedling mortality rate. To compensate for the expected border, corrugation, trickle, and sprinkler irrigation systems high mortality rate, the larger seedlings or a greater are suitable. The system used generally is governed by the crop that is grown. For the index for Douglas fir is 90. The yield at culmination of the efficient application and removal of surface irrigation water, mean annual increment is 4,200 cubic feet per acre in, a land leveling is needed. To prevent overirrigation and fully stocked, even-aged stand of trees at 60 years ad excessive erosion, applications of irrigation water should be 31,840 board feet per acre (Scribner rule) at 160 years. On adjusted to the available water capacity, the rate of water the basis of a 50-year curve, the mean site index is 70. intake, and the needs of the crop. The use of pipe, ditch The main limitations affecting timber production are lining, or drop structures in irrigation ditches reduces water compaction, seedling mortality, and plant competition. loss and the hazard of erosion. Conventional methods of harvesting timber generally are Returning all crop residue to the soil and using a suitable, but the soil may be compacted if it is moist when cropping system that includes grasses, legumes, or heavy equipment is used. Puddling can occur when the soil grass-legume mixtures help to maintain fertility and tilth. is wet. If the soil is excessively disturbed when timber is Leaving crop residue on or near the surface helps to harvested or logging roads are built, a larger number of rock conserve moisture and control erosion. fragments is left on the surface. A tillage pan forms easily if the soil is tilled when wet. Using low-pressure ground equipment causes less Chiseling or subsoiling breaks up the pan. Surface crusting damage to the soil and helps to maintain productivity. and compaction can be minimized by returning crop residue Compaction can be minimized by using suitable methods of to the soil. harvesting, laying out skid trails in advance, and harvesting Proper stocking rates, pasture rotation, and restricted timber when the soil is least susceptible to compaction. grazing during wet periods help to keep pastures in good Ripping skid trails and landings when the soil is dry can condition and protect the soil from erosion. Grazing when improve the growth of plants. the soil is wet results in compaction of the surface layer, Erosion can be controlled by carefully planning the poor tilth, and excessive runoff. Periodic mowing and construction and maintenance of logging roads, skid trails, clipping help to maintain uniform plant growth, discourage and landings. Seeding, mulching, and benching areas that selective grazing, and reduce the extent of clumpy growth. have been cut and filled also help to control erosion. Skid Fertilizer is needed to ensure the optimum growth of trails and unsurfaced roads may be impassable during grasses and legumes. Grasses respond to nitrogen, and rainy periods. Logging roads require suitable surfacing for legumes respond to sulfur and phosphorus. year-round use. Solid-set sprinkler irrigation is the best method of A high temperature in the surface layer and an controlling frost and providing adequate moisture for tree insufficient moisture supply in summer increase the seedling fruit. Compaction can be minimized by limiting the use of mortality rate. The large number of rock fragments in some equipment when the soil is wet. A permanent cover crop areas also increases the seedling mortality rate. To helps to control runoff and erosion. compensate for the expected high mortality rate, the larger This unit is well suited to homesite development. It has seedlings or a greater number of seedlings should be few limitations. Revegetating as soon as possible helps to planted. When the timber is harvested, leaving some of the control erosion in disturbed areas around construction sites. larger trees unharvested provides shade for seedlings. Gravel and cobbles should be removed from disturbed Reforestation can be accomplished by planting Douglas fir areas, particularly areas used for lawns. Topsoil can be and ponderosa pine seedlings. stockpiled and used to reclaim areas disturbed during Undesirable plants limit natural or artificial construction. In summer, irrigation is needed in areas that reforestation unless intensive site preparation and support lawn grasses, shrubs, vines, shade trees, or maintenance measures are applied. Mulching around ornamental trees. seedlings helps to maintain the moisture supply in This unit is suited to the production of ponderosa pine summer and minimizes competition from undesirable and Douglas fir. Other species that grow on this unit plants. include incense cedar, sugar pine, and Pacific madrone. The vegetative site is Douglas Fir-Mixed Pine-Fescue The understory vegetation includes deerbrush, tall Forest. Oregongrape, and western fescue. On the basis of a 100-year site curve, the mean site 158D-Ruch gravelly silt loam, 7 to 20 percent slopes. index for ponderosa pine is 115. The yield at culmination This very deep, well drained soil is on alluvial fans and foot of the mean annual increment is 5,280 cubic feet per acre slopes. It formed in alluvium derived dominantly from in a fully stocked, even-aged stand of trees at 40 years metamorphic rock. Elevation is 1,000 to 3,000 feet. The and 56,780 board feet per acre (Scribner rule) at 110 mean annual precipitation is 20 to 35 inches, the mean years. annual temperature is 50 to 54 On the basis of a 100-year site curve, the mean site degrees F, and the average frost-free period is 140 to 180 Also, waterways should be shaped and seeded to days. The native vegetation is mainly conifers and perennial grasses. hardwoods and an understory of grasses, shrubs, and Proper stocking rates, pasture rotation, and restricted forbs. grazing during wet periods help to keep pastures in good Typically, the surface layer is dark brown gravelly silt condition and protect the soil from erosion. Grazing when loam about 7 inches thick. The upper 10 inches of the the soil is wet results in compaction of the surface layer, subsoil is reddish brown loam. The lower 53 inches is poor tilth, and excessive runoff. Periodic mowing and yellowish red loam. The depth to bedrock is 60 inches or clipping help to maintain uniform plant growth, discourage more. In some areas the surface layer is cobbly or stony. selective grazing, and reduce the extent of clumpy growth. Included in this unit are small areas of Gregory soils Fertilizer is needed to ensure the optimum growth of near drainageways; Selmac soils on concave slopes; grasses and legumes. Grasses respond to nitrogen, and Vannoy and Voorhies soils on ridges and convex slopes; legumes respond to sulfur and phosphorus. Coleman, Foehlin, and Medford soils on terraces; and Solid-set sprinkler irrigation is the best method of Abegg, Manita, and Shefflein soils. Also included are small controlling frost and providing adequate moisture for tree areas of Xerorthents, small areas of Dumps, and small fruit. Compaction can be minimized by limiting the use of areas of Ruch soils that have slopes of more than 7 equipment when the soil is wet. A permanent cover crop percent. Included areas make up about 20 percent of the helps to control runoff and erosion. total acreage. The main limitation affecting homesite development is the Permeability is moderately slow in the Ruch soil. slope. Erosion is a hazard on the steeper slopes. Only the Available water capacity is about 8 inches. The effective part of the site that is used for construction should be rooting depth is 60 inches or more. Runoff is slow or disturbed. Revegetating as soon as possible helps to control medium, and the hazard of water erosion is slight or erosion in disturbed areas around construction sites. Gravel moderate. and cobbles should be removed from disturbed areas, This unit is used mainly for irrigated crops, such as particularly areas used for lawns. Topsoil can be stockpiled alfalfa hay, small grain, tree fruit, and grass-legume hay. It and used to reclaim areas disturbed during construction. also is used for timber production, pasture, and homesite Because of a low amount of rainfall in summer, irrigation is development. needed in areas that support lawn grasses, shrubs, vines, This unit is suited to irrigated crops. It is limited mainly by shade trees, or ornamental trees. the slope, the moderately slow permeability, and the This unit is suited to the production of ponderosa pine gravelly surface layer, which may limit the use of some and Douglas fir. Other species that grow on this unit equipment and increase maintenance costs. In summer, include incense cedar, sugar pine, and Pacific madrone. irrigation is needed for the maximum production of most The understory vegetation includes deerbrush, tall crops. Because of the slope, sprinkler and trickle irrigation Oregongrape, and western fescue. systems are the best methods of applying water. These On the basis of a 100-year site curve, the mean site systems permit an even, controlled application of water, index for ponderosa pine is 115. The yield at culmination of help to prevent excessive runoff, and minimize the risk of the mean annual increment is 5,280 cubic feet per acre in erosion. To prevent overirrigation and excessive erosion, a fully stocked, even-aged stand of trees at 40 years and applications of irrigation water should be adjusted to the 56,780 board feet per acre (Scribner rule) at 110 years. available water capacity, the rate of water intake, and the On the basis of a 100-year site curve, the mean site needs of the crop. index for Douglas fir is 90. The yield at culmination of the Returning all crop residue to the soil and using a mean annual increment is 4,200 cubic feet per acre in a cropping system that includes grasses, legumes, or fully stocked, even-aged stand of trees at 60 years and grass-legume mixtures help to maintain fertility and tilth. 31,840 board feet per acre (Scribner rule) at 160 years. On Leaving crop residue on or near the surface helps to the basis of a 50-year curve, the mean site index is 70. conserve moisture and control erosion. The main limitations affecting timber production are A tillage pan forms easily if the soil is tilled when wet. erosion, compaction, seedling mortality, and plant Chiseling or subsoiling breaks up the pan. Surface crusting competition. Conventional methods of harvesting timber and compaction can be minimized by returning crop residue generally. are suitable, but the soil may be compacted if it is to the soil. moist when heavy equipment is used. Puddling can occur The hazard of erosion can be reduced if fall grain is when the soil is wet. If the soil is excessively seeded early, stubble-mulch tillage is used, and tillage and seeding are on the contour or across the slope. disturbed when timber is harvested or logging roads are Included in this unit are small areas of Snowlin soils on built, a larger number of rock fragments is left on the concave slopes, poorly drained soils near drainageways surface. Using low-pressure ground equipment causes less and on concave slopes, Woodseye soils and Rock outcrop damage to the soil and helps to maintain productivity. on convex slopes, and soils that are similar to the Compaction can be minimized by using suitable methods of Rustlerpeak soil but have bedrock at a depth of more than harvesting, laying out skid trails in advance, and harvesting 40 inches. Also included are small areas of Rustlerpeak timber when the soil is least susceptible to compaction. soils that have slopes of less than 3 or more than 12 Ripping skid trails and landings when the soil is dry can percent. Included areas make up about 15 percent of the improve the growth of plants. total acreage. Erosion can be controlled by carefully planning the Permeability is moderately slow in the Rustlerpeak construction and maintenance of logging roads, skid trails, soil. Available water capacity is about 5 inches. The and landings. Seeding, mulching, and benching areas that effective rooting depth is 20 to 40 inches. Runoff is slow, have been cut and filled also help to control erosion. Skid and the hazard of water erosion is slight. trails and unsurfaced roads may be impassable during This unit is used for timber production, livestock . rainy periods. Logging roads require suitable surfacing for grazing, and wildlife habitat. year-round use. This unit is suited to the production of white fir. Other A high temperature in the surface layer and an species that grow on this unit include Douglas fir, incense insufficient moisture supply in summer increase the cedar and Rocky Mountain maple. The understory seedling mortality rate. The large number of rock fragments vegetation includes cascade Oregongrape, western white in some areas also increases the seedling mortality rate. To anemone, and gooseberry. compensate for the expected high mortality rate, the larger On the basis of a 50-year site curve, the mean site seedlings or a greater number of seedlings should be index for white fir is 75. The yield at culmination of the planted. When the timber is harvested, leaving some of the mean annual increment is 12,530 cubic feet per acre in a larger trees unharvested provides shade for seedlings. fully stocked, even-aged stand of trees at 70 years. Reforestation can be accomplished by planting Douglas fir The main limitations affecting timber production are and ponderosa pine seedlings. compaction, erosion, seedling mortality, and plant Undesirable plants limit natural or artificial competition. Also, the bedrock restricts root growth. As a reforestation unless intensive site preparation and result, windthrow is a hazard. maintenance measures are applied. Mulching around Conventional methods of harvesting timber generally are seedlings helps to maintain the moisture supply in suitable, but the soil may be compacted if it is moist when summer and minimizes competition from undesirable heavy equipment is used. Puddling can occur when the soil plants. is wet. If the soil is excessively disturbed when timber is The vegetative site is Douglas Fir-Mixed Pine-Fescue harvested or logging roads are built, a larger number of rock Forest. fragments is left on the surface. Using low-pressure ground equipment causes less damage to the soil and helps to 159C-Rustlerpeak gravelly loam, 3 to 12 percent maintain productivity. Compaction can be minimized by slopes. This moderately deep, well drained soil is on using suitable methods of harvesting, laying out skid trails in plateaus. It formed in colluvium derived from andesite and advance, and harvesting timber when the soil is least volcanic ash. Elevation is 4,000 to 6,100 feet. The mean susceptible to compaction. Ripping skid trails and landings annual precipitation is 40 to 50 inches, the mean annual when the soil is dry can improve the growth of plants. temperature is 40 to 45 degrees F, and the average Erosion can be controlled by carefully planning the frost-free period is less than 100 days. The native construction and maintenance of logging roads, skid trails, vegetation is mainly conifers and an understory of grasses, and landings. Seeding, mulching, and benching areas that shrubs, and forbs. have been cut and filled also help to control erosion. Skid Typically, the surface is covered with a layer of needles, trails and unsurfaced roads may be impassable during leaves, and twigs about 1 inch thick. The surface layer is rainy periods. Logging roads require suitable surfacing for dark reddish brown gravelly loam about 12 inches thick. year-round use. The subsoil is dark reddish brown very cobbly clay loam Severe frost can damage or kill seedlings. Air about 11 inches thick. Weathered bedrock is at a depth of drainage is restricted on this unit. Proper timber about 23 inches. The depth to bedrock ranges from 20 to harvesting methods can reduce the effect of frost on 40 inches. In some areas the surface layer is stony. regeneration. Reforestation can be accomplished by planting seedlings of frost-tolerant species, such as ponderosa pine and lodgepole pine. Undesirable plants limit natural or artificial included are small areas of Rustlerpeak soils that have reforestation unless intensive site preparation and slopes of less than 12 or more than 35 percent. Included maintenance measures are applied. Mulching around areas make up about 15 percent of the total acreage. seedlings helps to maintain the moisture supply in Permeability is moderately slow in the Rustlerpeak soil. summer and minimizes competition from undesirable Available water capacity is about 5 inches. The effective plants. rooting depth is 20 to 40 inches. Runoff is medium, and The main limitation affecting livestock grazing is the hazard of water erosion is moderate. compaction. The native vegetation suitable for grazing This unit is used for timber production, livestock includes Canada bluegrass, Alaska oniongrass, and grazing, and wildlife habitat. mountain brome. If the understory is overgrazed, the This unit is suited to the production of white fir. Other proportion of preferred forage plants decreases and the species that grow on this unit include Douglas fir, incense proportion of less preferred forage plants increases. cedar and Rocky Mountain maple. The understory A planned grazing system that includes timely deferment vegetation includes cascade Oregongrape, western white of grazing, rotation grazing, and proper livestock distribution anemone, and gooseberry. helps to prevent overgrazing of the understory and damage On the basis of a 50-year site curve, the mean site to the soil. Grazing should be delayed until the more index for white fir is 75. The yield at culmination of the desirable forage plants have achieved enough growth to mean annual increment is 12,530 cubic feet per acre in a withstand grazing pressure and the soil is firm enough to fully stocked, even-aged stand of trees at 70 years. withstand trampling by livestock. The main limitations affecting timber production are Thinning, logging, and fire reduce the density of the erosion, compaction, plant competition, and seedling overstory canopy and increase the production of mortality. Also, the bedrock restricts root growth. As a understory vegetation. Areas that support a large amount result, windthrow is a hazard. of competing vegetation can be improved by prescribed Wheeled and tracked logging equipment can be used in burning or by chemical or mechanical treatment. Seeding the less sloping areas, but cable yarding generally is safer disturbed areas to suitable plants increases forage in the more sloping areas and results in less surface production and reduces the risk of erosion. The seedling disturbance. If the soil is excessively disturbed when timber survival rate may be low, however, because of cold is harvested or logging roads are built, a larger number of temperatures in spring. rock fragments is left on the surface. Using standard The vegetative site is White Fir Forest. wheeled and tracked equipment when the soil is moist causes rutting and compaction. Puddling can occur when 160E-Rustlerpeak gravelly loam, 12 to 35 percent the soil is wet. Using low-pressure ground equipment north slopes. This moderately deep, well drained soil is on causes less damage to the soil and helps to maintain hillslopes. It formed in colluvium derived from andesite and productivity. Compaction can be minimized by using suitable volcanic ash. Elevation is 4,000 to 6,100 feet. The mean methods of harvesting, laying out skid trails in advance, and annual precipitation is 40 to 50 inches, the mean annual harvesting timber when the soil is least susceptible to temperature is 40 to 45 degrees F, and the average compaction. Ripping skid trails and landings when the soil is frost-free period is less than 100 days. The native dry can improve the growth of plants. vegetation is mainly conifers and an understory of grasses, Properly designed road drainage systems that include shrubs, and forbs. carefully located culverts help to control erosion. Seeding, Typically, the surface is covered with a layer of needles, mulching, and benching areas that have been cut and filled leaves, and twigs about 1 inch thick. The surface layer is also help to control erosion. Steep yarding paths, skid trails, dark reddish brown gravelly loam about 12 inches thick. and firebreaks are subject to rilling and gullying unless they The subsoil is dark reddish brown very cobbly clay loam are protected by a plant cover or adequate water bars, or about 11 inches thick. Weathered bedrock is at a depth of both. Skid trails and unsurfaced roads may be impassable about 23 inches. The depth to bedrock ranges from 20 to during rainy periods. Logging roads require suitable 40 inches. In some areas the surface layer is stony. surfacing for year-round use. Included in this unit are small areas of Snowlin soils on Undesirable plants limit natural or artificial reforestation concave slopes, poorly drained soils near drainageways unless intensive site preparation and maintenance and on concave slopes, Woodseye soils and Rock outcrop measures are applied. Reforestation can be accomplished on ridges and convex slopes, and soils that are similar to by planting ponderosa pine and Douglas fir seedlings. the Rustlerpeak soil but have bedrock at a depth of more Mulching around seedlings helps than 40 inches. Also to maintain the moisture supply in summer and than 40 inches. Also included are small areas of minimizes competition from undesirable plants. Rustlerpeak soils that have slopes of less than 35 or Severe frost can damage or kill seedlings. In the less more than 65 percent. Included areas make up about 15 sloping areas where air drainage may be restricted, proper percent of the total acreage. timber harvesting methods can reduce the effect of frost on Permeability is moderately slow in the Rustlerpeak regeneration. soil. Available water capacity is about 5 inches. The The main limitations affecting livestock grazing are effective rooting depth is 20 to 40 inches. Runoff is rapid, compaction and erosion. The native vegetation suitable for and the hazard of water erosion is high. grazing includes Canada bluegrass, Alaska oniongrass, This unit is used for timber production, livestock and mountain brome. If the understory is overgrazed, the grazing, and wildlife habitat. proportion of preferred forage plants decreases and the This unit is suited to the production of white fir. Other proportion of less preferred forage plants increases. species that grow on this unit include Douglas fir, incense A planned grazing system that includes timely deferment cedar and Rocky Mountain maple. The understory of grazing, rotation grazing, and proper livestock distribution vegetation includes cascade Oregongrape, western white helps to prevent overgrazing of the understory and damage anemone, and gooseberry. to the soil. Grazing should be delayed until the more On the basis of a 50-year site curve, the mean site index desirable forage plants have achieved enough growth to for white fir is 75. The yield at culmination of the mean withstand grazing pressure and the soil is firm enough to annual increment is 12,530 cubic feet per acre in a fully withstand trampling by livestock. stocked, even-aged stand of trees at 70 years. Thinning, logging, and fire reduce the density of the The main limitations affecting timber production are the overstory canopy and increase the production of slope, erosion, compaction, plant competition, and understory vegetation. Areas that support a large amount seedling mortality. Also, the bedrock restricts root growth. of competing vegetation can be improved by prescribed As a result, windthrow is a hazard. burning or by chemical or mechanical treatment. Seeding Wheeled and tracked logging equipment can be used in disturbed areas to suitable plants increases forage the less sloping areas, but cable yarding generally is safer production and reduces the risk of erosion. The seedling and results in less surface disturbance. If the soil is survival rate may be low, however, because of cold excessively disturbed when timber is harvested or logging temperatures in spring. roads are built, a larger number of rock fragments is left on The vegetative site is White Fir Forest. the surface. Using standard wheeled and tracked equipment when the soil is moist causes rutting and compaction. 160G-Rustlerpeak gravelly loam, 35 to 65 percent Puddling can occur when the soil is wet. Using low-pressure north slopes. This moderately deep, well drained soil is on ground equipment causes less damage to the soil and helps hillslopes. It formed in colluvium derived from andesite and to maintain productivity. Compaction can be minimized by volcanic ash. Elevation is 4,000 to 6,100 feet. The mean using suitable methods of harvesting, laying out skid trails in annual precipitation is 40 to 50 inches, the mean annual advance, and harvesting timber when the soil is least temperature is 40 to 45 degrees F, and the average susceptible to compaction. Ripping skid trails and landings frost-free period is less than 100 days. The native when the soil is dry can improve the growth of plants. vegetation is mainly conifers and an understory of grasses, Properly designed road drainage systems that include shrubs, and forbs. carefully located culverts help to control erosion. Seeding, Typically, the surface is covered with a layer of needles, mulching, and benching areas that have been cut and filled leaves, and twigs about 1 inch thick. The surface layer is also help to control erosion. Steep yarding paths, skid trails, dark reddish brown gravelly loam about 12 inches thick. and firebreaks are subject to rilling and gullying unless they The subsoil is dark reddish brown very cobbly clay loam are protected by a plant cover or adequate water bars, or about 11 inches thick. Weathered bedrock is at a depth of both. Cutbanks occasionally slump when the soil is about 23 inches. The depth to bedrock ranges from 20 to saturated. 40 inches. In some areas the surface layer is stony. Constructing logging roads on the steeper slopes can Included in this unit are small areas of Snowlin soils on result in a high risk of erosion. Building the roads at concave slopes and on the less sloping parts of the midslope requires extensive cutting and filling and removes landscape, Woodseye soils and Rock outcrop on ridges land from production. Material that is discarded when the and convex slopes, and soils that are similar to the roads are built can damage vegetation and is a potential Rustlerpeak soil but have bedrock at a depth of more source of sedimentation. If the material becomes saturated, avalanches of debris can occur. End hauling of the waste material minimizes Included in this unit are small areas of Snowlin soils on damage to the vegetation downslope and reduces the risk concave slopes and on the less sloping parts of the of sedimentation. Skid trails and unsurfaced roads may be landscape, Woodseye soils on ridges and convex slopes, impassable during rainy periods. Logging roads require and soils that are similar to the Rustlerpeak soil but have suitable surfacing for year-round use. bedrock at a depth of less than 20 or more than 40 inches. Undesirable plants limit natural or artificial reforestation Also included are small areas of Rustlerpeak soils that have unless intensive site preparation and maintenance slopes of less than 35 or more than 70 percent. Included measures are applied. Reforestation can be accomplished areas make up about 10 percent of the total acreage. by planting ponderosa pine and Douglas fir seedlings. The Rustlerpeak soil is moderately deep and well Mulching around seedlings helps to maintain the moisture drained. It formed in colluvium derived dominantly from supply in summer and minimizes competition from andesite and volcanic ash. Typically, the surface is covered undesirable plants. with a layer of needles, leaves, and twigs about 1 inch thick. Severe frost can damage or kill seedlings. Proper timber The surface layer is dark reddish brown gravelly loam about harvesting methods can reduce the effect of frost on 12 inches thick. The subsoil is dark reddish brown very regeneration. cobbly clay loam about 11 inches thick. Weathered bedrock The main limitations affecting livestock grazing are is at a depth of about 23 inches. The depth to bedrock erosion, compaction, and the slope. The native vegetation ranges from 20 to 40 inches. In some areas the surface suitable for grazing includes Canada bluegrass, Alaska layer is stony. oniongrass, and mountain brome. If the understory is Permeability is moderately slow in the Rustlerpeak overgrazed, the proportion of preferred forage plants soil. Available water capacity is about 5 inches. The decreases and the proportion of less preferred forage plants effective rooting depth is 20 to 40 inches. Runoff is rapid, increases. and the hazard of water erosion is high. A planned grazing system that includes timely deferment Rock outcrop consists of areas of exposed bedrock. of grazing, rotation grazing, and proper livestock distribution Runoff is very rapid in these areas. helps to prevent overgrazing of the understory and damage This unit is used for timber production, livestock to the soil. Grazing should be delayed until the more grazing, and wildlife habitat. desirable forage plants have achieved enough growth to This unit is suited to the production of white fir. Other withstand grazing pressure and the soil is firm enough to species that grow on this unit include Douglas fir, incense withstand trampling by livestock. Because of the slope and cedar, and Rocky Mountain maple. The understory the Rock outcrop, areas of this unit can hinder livestock vegetation includes cascade Oregongrape, western white movement. anemone, and gooseberry. Thinning, logging, and fire reduce the density of the On the basis of a 50-year site curve, the mean site index overstory canopy and increase the production of for white fir is 75. The yield at culmination of the mean understory vegetation. Areas that support a large amount annual increment is 12,530 cubic feet per acre in a fully of competing vegetation can be improved by prescribed stocked, even-aged stand of trees at 70 years. burning or by chemical or mechanical treatment. Seeding The main limitations affecting timber production are the disturbed areas to suitable plants increases forage slope, the Rock outcrop, erosion, compaction, plant production and reduces the risk of erosion. The seedling competition, and seedling mortality. Also, the bedrock survival rate may be limited, however, because of cold restricts root growth. As a result, windthrow is a hazard. temperatures in spring. Wheeled and tracked logging equipment can be used in The vegetative site is White Fir Forest. the less sloping areas, but cable yarding generally is safer and results in less surface disturbance. The Rock outcrop 161G-Rustlerpeak-Rock outcrop complex, 35 to 70 can cause breakage of falling timber and can hinder percent north slopes. This map unit is on hillslopes. yarding. If the soil is excessively disturbed when timber is Elevation is 4,000 to 6,100 feet. The mean annual harvested or logging roads are built, a larger number of rock precipitation is 40 to 50 inches, the mean annual fragments is left on the surface. Using standard wheeled temperature is 40 to 45 degrees F, and the average and tracked equipment when the soil is moist causes rutting frost-free period is less than 100 days. The native and compaction. Puddling can occur when the soil is wet. vegetation is mainly conifers and an understory of grasses, Using low-pressure ground equipment causes less damage shrubs, and forbs. to the soil and helps to maintain productivity. Compaction This unit is about 70 percent Rustlerpeak soil and 20 can be minimized by using suitable methods of harvesting, percent Rock outcrop. The components of this unit occur as laying out skid trails in advance, and harvesting timber when areas so intricately intermingled that mapping them the soil is separately was not practical at the scale used. least susceptible to compaction. Ripping skid trails and increases forage production and reduces the risk of landings when the soil is dry can improve the growth of erosion. The seedling survival rate may be limited, plants. however, because of cold temperatures in spring. Properly designed road drainage systems that include The vegetative site is White Fir Forest. carefully located culverts help to control erosion Seeding, mulching, and benching areas that have been cut and filled 162B-Selmac loam, 2 to 7 percent slopes. This very also help to control erosion. Steep yarding paths, skid trails, deep, moderately well drained soil is in basins. It formed in and firebreaks are subject to rilling and gullying unless they alluvium derived dominantly from sedimentary and volcanic are protected by a plant cover or adequate water bars, or rock and underlain by clayey sediment. Elevation is 1,000 to both. Cutbanks occasionally slump when the soil is 3,000 feet. The mean annual precipitation is 25 to 40 saturated. inches, the mean annual temperature is 50 to 54 degrees F, Constructing logging roads on the steeper slopes can and the average frost-free period is 140 to 180 days. The result in a high risk of erosion. Building the roads at native vegetation is mainly hardwoods and an understory of midslope requires extensive cutting and filling and removes grasses, shrubs, and forbs. land from production. Material that is discarded when the Typically, the surface layer is dark brown loam about 17 roads are built can damage vegetation and is a potential inches thick. The subsoil is reddish brown clay loam about source of sedimentation. If the material becomes saturated, 12 inches thick. The substratum to a depth of 60 inches is avalanches of debris can occur. End hauling of the waste olive brown clay. The depth to bedrock is 60 inches or material minimizes damage to the vegetation downslope more. and reduces the risk of sedimentation. Skid trails and Included in this unit are small areas of Darow, Manita, unsurfaced roads may be impassable during rainy periods. and Vannoy soils on hillslopes; Debenger and Ruch soils on Logging roads require suitable surfacing for year-round use. convex slopes; Langellain soils; and Gregory soils and Undesirable plants limit natural or artificial reforestation poorly drained or very poorly drained, loamy soils near unless intensive site preparation and maintenance drainageways and on concave slopes. Also included are measures are applied. Reforestation can be accomplished small areas of Selmac soils that have slopes of more than 7 by planting ponderosa pine and Douglas fir seedlings. percent. Included areas make up about 15 percent of the Mulching around seedlings helps to maintain the moisture total acreage. supply in summer and minimizes competition from Permeability is moderately slow to a depth of 29 inches undesirable plants. in the Selmac soil and very slow below that depth. Severe frost can damage or kill seedlings. Proper timber Available water capacity is about 8 inches. The effective harvesting methods can reduce the effect of frost on rooting depth is limited by the dense, clayey substratum, regeneration. which is at a depth of 12 to 36 inches. Runoff is slow, and The main limitations affecting livestock grazing are the hazard of water erosion is slight. The water table, erosion, compaction, the slope, and the Rock outcrop. The which is perched above the layer of clay, is at a depth of native vegetation suitable for grazing includes Canada 1.5 to 3.0 feet from December through May. bluegrass, Alaska oniongrass, and mountain brome. If the This unit is used mainly for hay and pasture. It also is understory is overgrazed, the proportion of preferred forage used for small grain, tree fruit, and homesite plants decreases and the proportion of less preferred forage development. plants increases. This unit is suited to irrigated crops. It is limited mainly by A planned grazing system that includes timely deferment wetness in winter and spring and the very slow permeability. of grazing, rotation grazing, and proper livestock distribution Crops that require good drainage can be grown if a properly helps to prevent overgrazing of the understory and damage designed tile drainage system is installed. Tile drainage can to the soil. Grazing should be delayed until the more lower the water table if collection laterals are closely spaced desirable forage plants have achieved enough growth to and a suitable outlet is available. Land smoothing and open withstand grazing pressure and the soil is firm enough to ditches can reduce surface wetness. withstand trampling by livestock. In summer, irrigation is needed for the maximum Thinning, logging, and fire reduce the density of the production of most crops. Furrow, border, corrugation, overstory canopy and increase the production of trickle, and sprinkler irrigation systems are suitable. The understory vegetation. Areas that support a large amount system used generally is governed by the crop that is of competing vegetation can be improved by prescribed grown. For the efficient application and removal of surface burning or by chemical or mechanical treatment. Seeding irrigation water, land leveling is needed. To disturbed areas to suitable plants prevent overirrigation and the development of a perched erosion in disturbed areas around construction sites. water table, applications of irrigation water should be Topsoil can be stockpiled and used to reclaim areas adjusted to the available water capacity, the rate of water disturbed during construction. In many areas it may be intake, and the needs of the crop. The use of pipe, ditch necessary to haul in topsoil for lawns and gardens. lining, or drop structures in irrigation ditches reduces water Because of a low amount of rainfall in summer, irrigation is loss and the hazard of erosion. needed in areas that support lawn grasses, shrubs, vines, Returning all crop residue to the soil and using a shade trees, or ornamental trees. cropping system that includes grasses, legumes, or The vegetative site is Loamy Hills, 20- to 35-inch grass-legume mixtures help to maintain fertility and tilth. precipitation zone. Leaving crop residue on or near the surface helps to conserve moisture and control erosion. 162D-Selmac loam, 7 to 20 percent slopes. This very A tillage pan forms easily if the soil is tilled when wet. deep, moderately well drained soil is in basins. It formed in Chiseling or subsoiling breaks up the pan. Surface crusting alluvium derived dominantly from sedimentary and volcanic and compaction can be minimized by returning crop residue rock and underlain by clayey sediment. Elevation is 1,000 to to the soil. 3,000 feet. The mean annual precipitation is 25 to 40 Solid-set sprinkler irrigation is the best method of inches, the mean annual temperature is 50 to 54 degrees F, controlling frost and providing adequate moisture for tree and the average frost-free period is 140 to 180 days. The fruit. Compaction can be minimized by limiting the use of native vegetation is mainly hardwoods and an understory of equipment when the soil is wet. A permanent cover crop grasses, shrubs, and forbs. helps to control runoff and erosion. Typically, the surface layer is dark brown loam about 17 Proper stocking rates, pasture rotation, and restricted inches thick. The subsoil is reddish brown clay loam about grazing during wet periods help to keep pastures in good 12 inches thick. The substratum to a depth of 60 inches is condition and protect the soil from erosion. Grazing when olive brown clay. The depth to bedrock is 60 inches or the soil is wet results in compaction of the surface layer, more. poor tilth, and excessive runoff. Periodic mowing and Included in this unit are small areas of Darow, Manita, clipping help to maintain uniform plant growth, discourage and Vannoy soils on hillslopes; Debenger and Ruch soils on selective grazing, and reduce the extent of clumpy growth. convex slopes; Langellain soils; and Gregory soils and Fertilizer is needed to ensure the optimum growth of poorly drained or very poorly drained, loamy soils near grasses and legumes. Grasses respond to nitrogen, and drainageways and on concave slopes. Also included are legumes respond to sulfur and phosphorus. small areas of Selmac soils that have slopes of less than 7 The main limitations affecting homesite development or more than 20 percent. Included areas make up about 15 are the wetness, the very slow permeability, a high percent of the total acreage. shrink-swell potential, and low strength. Permeability is moderately slow to a depth of 29 inches The very slow permeability and the seasonal high water in the Selmac soil and very slow below that depth. table increase the possibility that septic tank absorption Available water capacity is about 8 inches. The effective fields will fail. Interceptor ditches can divert subsurface rooting depth is limited by the dense, clayey substratum, water and thus improve the efficiency of the absorption which is at a depth of 12 to 36 inches. Runoff is medium, fields. Alternative waste disposal systems may function and the hazard of water erosion is moderate. The water properly on this unit. Suitable included soils are throughout table, which is perched above the layer of clay, is at a the unit. Onsite investigation is needed to locate such soils. depth of 1.5 to 3.0 feet from December through May. Because the seasonal high water table is perched above This unit is used mainly for hay and pasture. It also is the layer of clay, a drainage system is needed on sites for used for tree fruit, small grain, and homesite buildings with basements and crawl spaces. The wetness development. can be reduced by installing drainage tile around footings. This unit is suited to irrigated crops. It is limited mainly Properly designing foundations and footings, diverting runoff by wetness in winter and spring, the very slow permeability, away from the buildings, and backfilling with material that and the slope. Crops that require good drainage can be has a low shrink-swell potential help to prevent the structural grown if a properly designed drainage system is installed. damage caused by shrinking and swelling. Properly The ability of tile drains to remove subsurface water from designing buildings and roads helps to offset the limited the soil is limited because of the slope and the very slow ability of the soil to support a load. permeability in the substratum. Wetness can be reduced by Revegetating as soon as possible helps to control interceptor drains. Open ditches can reduce surface wetness. In summer, irrigation is needed for the maximum The wetness can be reduced by installing drainage tile production of most crops. Because of the slope, sprinkler around footings. Properly designing foundations and irrigation is the best method of applying water. This method footings, diverting runoff away from the buildings, and permits an even, controlled application of water, helps to backfilling with material that has a low shrink -swell potential prevent excessive runoff, and minimizes the risk of erosion. help to prevent the structural damage caused by shrinking To prevent overirrigation and excessive erosion, and swelling. Properly designing buildings and roads helps applications of irrigation water should be adjusted to the to offset the limited ability of the soil to support a load. available water capacity, the rate of water intake, and the Erosion is a hazard on the steeper slopes. Only the part needs of the crop. of the site that is used for construction should be disturbed. Returning all crop residue to the soil and using a Revegetating as soon as possible helps to control erosion cropping system that includes grasses., legumes, or in disturbed areas around construction sites. Topsoil can grass-legume mixtures help to maintain fertility and tilth. be stockpiled and used to reclaim areas disturbed during Leaving crop residue on or near the surface helps to construction. In many areas it may be necessary to haul in conserve moisture and control erosion. topsoil for lawns and gardens. Because of a low amount of A tillage pan forms easily if the soil is tilled when wet. rainfall in summer, irrigation is needed in areas that support Chiseling or subsoiling breaks up the pan. Surface crusting lawn grasses, shrubs, vines, shade trees, or ornamental and compaction can be minimized by returning crop residue trees. to the soil. The vegetative site is Loamy Hills, 20- to 35-inch The hazard of erosion can be reduced if fall grain is precipitation zone. seeded early, stubble-mulch tillage is used, and tillage and seeding are on the contour or across the slope. Also, 163A-Sevenoaks loamy sand, 0 to 3 percent slopes. waterways should be shaped and seeded to perennial This very deep, somewhat excessively drained soil is on grasses. stream terraces. It formed in alluvium derived from mixed Seedbeds should be prepared on the contour or across sources and containing various amounts of pumice and the slope where practical. Proper stocking rates, pasture volcanic ash. Elevation is 1,000 to 1,500 feet. The mean rotation, and restricted grazing during wet periods help to annual precipitation is 18 to 25 inches, the mean annual keep pastures in good condition and protect the soil from temperature is 50 to 54 degrees F, and the average erosion. Grazing when the soil is wet results in compaction frost-free period is 150 to 180 days. The vegetation in areas of the surface layer, poor tilth, and excessive runoff. Periodic that have not been cultivated is mainly hardwoods and an mowing and clipping help to maintain uniform plant growth, understory of grasses, shrubs, and forbs. discourage selective grazing, and reduce the extent of Typically, the surface layer is very dark brown loamy clumpy growth. Fertilizer is needed to ensure the optimum sand about 14 inches thick. The next layer is dark brown growth of grasses and legumes. Grasses respond to gravelly sand about 8 inches thick. The substratum to a nitrogen, and legumes respond to sulfur and phosphorus. depth of 60 inches is dark grayish brown and olive brown Solid-set sprinkler irrigation is the best method of gravelly coarse sand and gravelly sand. In some areas the controlling frost and providing adequate moisture for tree surface layer is sandy loam. fruit. Compaction can be minimized by limiting the use of Included in this unit are small areas of Central Point, equipment when the soil is wet. A permanent cover crop Medford, and Takilma soils; Gregory soils on concave helps to control runoff and erosion. slopes; and Sevenoaks soils that have slopes of more than The main limitations affecting homesite development are 3 percent. Included areas -make up about 15 percent of the the wetness, the very slow permeability, a high shrink -swell total acreage. potential, and the slope. Permeability is moderately rapid in the Sevenoaks soil. The very slow permeability and the seasonal high water Available water capacity is about 6 inches. The effective table increase the possibility that septic tank absorption rooting depth is 60 inches or more. The substratum can fields will fail. Interceptor ditches can divert subsurface restrict the penetration of roots, however, because of water and thus improve the efficiency of the absorption droughtiness. Runoff is slow, and the hazard of water fields. Alternative waste disposal systems may function erosion is slight. properly on this unit. Suitable included soils are throughout This unit is used mainly for irrigated crops, such as the unit. Onsite investigation is needed to locate such soils. alfalfa hay, tree fruit, and small grain. Other crops Because the seasonal high water table is perched above the layer of clay, a drainage system is needed on sites for buildings with basements and crawl spaces. include corn for silage. Some areas are used for grass Establishing plants is difficult in areas where the surface hay, pasture, or homesite development. layer has been removed. Mulching and applying fertilizer This unit is suited to irrigated crops. It is limited mainly by help to establish plants in cut areas. In many areas it may a rapid rate of water intake and droughtiness. In summer, be necessary to haul in topsoil for lawns and gardens. irrigation is needed for the maximum production of most Because of a low amount of rainfall in summer, irrigation is crops. Because the rate of water intake is rapid, sprinkler needed in areas that support lawn grasses, shrubs, vines, and trickle irrigation systems are the best methods of shade trees, or ornamental trees. applying water. These systems permit an even, controlled The vegetative site is Deep Loamy Terrace, 18- to application of water, help to prevent excessive runoff, and 28-inch precipitation zone. minimize the risk of erosion. To prevent overirrigation and the leaching of plant nutrients, applications of irrigation 164B-Shefflein loam, 2 to 7 percent slopes. This water should be adjusted to the available water capacity, deep, well drained soil is on alluvial fans. It formed in the rate of water intake, and the needs of the crop. Because alluvium derived dominantly from granitic rock. Elevation the soil is droughty, the applications should be light and is 1,000 to 4,000 feet. The mean annual precipitation is 25 frequent. to 40 inches, the mean annual temperature is 46 to 54 Returning all crop residue to the soil and using a degrees F, and the average frost-free period is 100 to 160 cropping system that includes grasses, legumes, or days. The native vegetation is mainly conifers and grass-legume mixtures help to maintain fertility and tilth. hardwoods and an understory of grasses, shrubs, and Leaving crop residue on or near the surface helps to forbs. conserve moisture and control soil blowing. Typically, the surface layer is dark brown loam about 4 Solid-set sprinkler irrigation is the best method of inches thick. The next layer is reddish brown loam about 6 controlling frost and providing adequate moisture for tree inches thick. The upper 30 inches of the subsoil is reddish fruit. Compaction can be minimized by limiting the use of brown clay loam. The lower 16 inches is reddish brown equipment when the soil is wet and by planting a cover sandy clay loam. Weathered bedrock is at a depth of about crop. A permanent cover crop helps to control runoff and 56 inches. The depth to bedrock ranges from 40 to 60 erosion. inches. In some areas the surface layer is sandy loam or Proper stocking rates, pasture rotation, and restricted clay loam. grazing during wet periods help to keep pastures in good Included in this unit are small areas of Clawson and condition and protect the soil from erosion. Grazing when Kubli soils near drainageways and on concave slopes; the soil is wet results in compaction of the surface layer, Barron, Manita, and Ruch soils; and soils that are similar to poor tilth, and excessive runoff. Periodic mowing and the Shefflein soil but have bedrock at a depth of more than clipping help to maintain uniform plant growth, discourage 60 inches. Also included are small areas of Shefflein soils selective grazing, and reduce the extent of clumpy growth. that have slopes of more than 7 percent. Included areas Fertilizer is needed to ensure the optimum growth of make up about 20 percent of the total acreage. grasses and legumes. Grasses respond to nitrogen, and Permeability is moderately slow in the Shefflein soil. legumes respond to sulfur and phosphorus. Available water capacity is about 8 inches. The effective This unit is suited to homesite development. The main rooting depth is 40 to 60 inches. Runoff is slow, and the limitations are the moderately rapid permeability and hazard of water erosion is moderate. droughtiness. This unit is used mainly for hay and pasture, timber This unit is poorly suited to standard systems of waste production, or wildlife habitat. It also is used for homesite disposal because of the moderately rapid permeability. development. Alternative waste disposal systems may function properly This unit is well suited to irrigated crops. It is limited on this unit. Suitable included soils are throughout the unit. mainly by the moderately slow permeability and the hazard Onsite investigation is needed to locate such soils. of erosion. In summer, irrigation is needed for the maximum In some areas excavation for houses and access roads production of most crops. Sprinkler irrigation is the best exposes material that is highly susceptible to soil blowing. method of applying water. This method permits an even, Revegetating as soon as possible in disturbed areas around controlled application of water, helps to prevent excessive construction sites helps to control soil blowing. Cutbanks runoff, and minimizes the risk of erosion. Border and are not stable and are subject to slumping. To keep contour flood irrigation systems also are suitable. For the cutbanks from caving in, excavations may require special efficient application and removal of surface irrigation water, retainer walls. land leveling is needed. To prevent overirrigation and excessive erosion, applications of irrigation water should be adjusted of trees at 40 years and 56,780 board feet per acre to the available water capacity, the rate of water intake, (Scribner rule) at 110 years. and the needs of the crop. The use of pipe, ditch lining, or On the basis of a 100-year site curve, the mean site drop structures in irrigation ditches reduces water loss and index for Douglas fir is 105. The yield at culmination of the the hazard of erosion. mean annual increment is 5,460 cubic feet per acre in a Returning all crop residue to the soil and using a fully stocked, even-aged stand of trees at 60 years and cropping system that includes grasses, legumes, or 45,600 board feet per acre (Scribner rule) at 150 years. On grass-legume mixtures help to maintain fertility and tilth. the basis of a 50-year curve, the mean site index is 75. Leaving crop residue on or near the surface helps to The main limitations affecting timber production are conserve moisture and control erosion. compaction, seedling mortality, and plant competition. When A tillage pan forms easily if the soil is tilled when wet. timber is harvested, management that minimizes the risk of Chiseling or subsoiling breaks up the pan. Surface crusting erosion is essential. Conventional methods of harvesting and compaction can be minimized by returning crop residue timber generally are suitable, but the soil may be compacted to the soil. if it is moist when heavy equipment is used. Puddling can Proper stocking rates, pasture rotation, and restricted occur when the soil is wet. Using low-pressure ground grazing during wet periods help to keep pastures in good equipment causes less damage to the soil and helps to condition and protect the soil from erosion. Grazing when maintain productivity. Compaction can be minimized by the soil is wet results in compaction of the surface layer, using suitable methods of harvesting, laying out skid trails in poor tilth, and excessive runoff. Periodic mowing and advance, and harvesting timber when the soil is least clipping help to maintain uniform plant growth, discourage susceptible to compaction. Ripping skid trails and landings selective grazing, and reduce the extent of clumpy growth. when the soil is dry can improve the growth of plants. Fertilizer is needed to ensure the optimum growth of Erosion can be controlled by carefully planning the grasses and legumes. Grasses respond to nitrogen, and construction and maintenance of logging roads, skid trails, legumes respond to sulfur and phosphorus. and landings. Seeding, mulching, and benching areas that This unit is well suited to homesite development. The have been cut and filled also help to control erosion. Skid main limitations are the moderately slow permeability and trails and unsurfaced roads may be impassable during the shrink-swell potential. The moderately slow permeability rainy periods. Logging roads require suitable surfacing for can be overcome by increasing the size of the absorption year-round use. field. A high temperature in the surface layer and an If buildings are constructed on this unit, properly insufficient moisture supply in summer increase the designing foundations and footings, diverting runoff away seedling mortality rate. To compensate for the expected from the buildings, and backfilling with material that has a high mortality rate, the larger seedlings or a greater number low shrink -swell potential help to prevent the structural of seedlings should be planted. When the timber is damage caused by shrinking and swelling. Properly harvested, leaving some of the larger trees unharvested designing buildings and roads helps to offset the limited provides shade for seedlings. Reforestation can be ability of the soil to support a load. accomplished by planting Douglas fir and ponderosa pine Revegetating as soon as possible helps to control seedlings. erosion in disturbed areas around construction sites. Undesirable plants limit natural or artificial Topsoil can be stockpiled and used to reclaim areas reforestation unless intensive site preparation and disturbed during construction. Because of a low amount of maintenance measures are applied. Mulching around rainfall in summer, irrigation is needed in areas that support seedlings helps to maintain the moisture supply in lawn grasses, shrubs, vines, shade trees, or ornamental summer and minimizes competition from undesirable trees. plants. This unit is suited to the production of Douglas fir and Increased erosion, loss of plant nutrients, and water ponderosa pine. Other species that grow on this unit repellency are likely to result from fires of moderate include incense cedar, sugar pine, and Pacific madrone. intensity. The understory vegetation includes deerbrush, tall The vegetative site is Douglas Fir-Mixed Pine-Fescue Oregongrape, and western fescue. Forest. On the basis of a 100-year site curve, the mean site index for ponderosa pine is 115. The yield at culmination 164D-Shefflein loam, 7 to 20 percent slopes. This of the mean annual increment is 5,280 cubic feet per acre deep, well drained soil is on alluvial fans. It formed in in a fully stocked, even-aged stand alluvium derived dominantly from granitic rock. Elevation is 1,000 to 4,000 feet. The mean annual periods help to keep pastures in good condition and protect precipitation is 25 to 40 inches, the mean annual the soil from erosion. Grazing when the soil is wet results in temperature is 46 to 54 degrees F, and the average compaction of the surface layer, poor tilth, and excessive frost-free period is 100 to 160 days. The native runoff. Periodic mowing and clipping help to maintain vegetation is mainly conifers and hardwoods and an uniform plant growth, discourage selective grazing, and understory of grasses, shrubs, and forbs. reduce the extent of clumpy growth. Fertilizer is needed to Typically, the surface layer is dark brown loam about 4 ensure the optimum growth of grasses and legumes. inches thick. The next layer is reddish brown loam about 6 Grasses respond to nitrogen, and legumes respond to sulfur inches thick. The upper 30 inches of the subsoil is reddish and phosphorus. brown clay loam. The lower 16 inches is reddish brown The main limitations affecting homesite development are sandy clay loam. Weathered bedrock is at a depth of about the moderately slow permeability, the shrink-swell potential, 56 inches. The depth to bedrock ranges from 40 to 60 and the slope. The moderately slow permeability can be inches. In some areas the surface layer is sandy loam or overcome by increasing the size of the absorption field. clay loam or is stony. If buildings are constructed on this unit, properly Included in this unit are small areas of Clawson and designing foundations and footings, diverting runoff away Kubli soils near drainageways and on concave slopes; from the buildings, and backfilling with material that has a Tallowbox soils on the more sloping parts of the landscape; low shrink -swell potential help to prevent the structural Barron, Manita, and Ruch soils; and soils that are similar to damage caused by shrinking and swelling. Properly the Shefflein soil but have bedrock at a depth of less than designing buildings and roads helps to offset the limited 40 or more than 60 inches. Also included are small areas of ability of the soil to support a load. Shefflein soils that have slopes of less than 7 or more than Erosion is a hazard on the steeper slopes. Only the 20 percent. Included areas make up about 20 percent of part of the site that is used for construction should be the total acreage. disturbed. Revegetating as soon as possible helps to Permeability is moderately slow in the Shefflein soil. control erosion in disturbed areas around construction Available water capacity is about 8 inches. The effective sites. Topsoil can be stockpiled and used to reclaim areas rooting depth is 40 to 60 inches. Runoff is medium, and the disturbed during construction. Because of a low amount of hazard of water erosion is moderate or high. rainfall in summer, irrigation is needed in areas that This unit is used mainly for timber production or wildlife support lawn grasses, shrubs, vines, shade trees, or habitat. It also is used for hay and pasture and for ornamental trees. homesite development. This unit is suited to the production of Douglas fir and This unit is suited to irrigated crops. It is limited mainly by ponderosa pine. Other species that grow on this unit the slope, the hazard of erosion, and the moderately slow include incense cedar, sugar pine, and Pacific madrone. permeability. In summer, irrigation is needed for the The understory vegetation includes deerbrush, tall maximum production of most crops. Because of the slope, Oregongrape, and western fescue. sprinkler irrigation is the best method of applying water. This On the basis of a 100-year site curve, the mean site method permits an even, controlled application of water, index for ponderosa pine is 115. The yield at culmination of helps to prevent excessive runoff, and minimizes the risk of the mean annual increment is 5,280 cubic feet per acre in erosion. To prevent overirrigation and excessive erosion, a fully stocked, even-aged stand of trees at 40 years and applications of irrigation water should be adjusted to the 56,780 board feet per acre (Scribner rule) at 110 years. available water capacity, the rate of water intake, and the On the basis of a 100-year site curve, the mean site needs of the crop. index for Douglas fir is 105. The yield at culmination of the Returning all crop residue to the soil and using a mean annual increment is 5,460 cubic feet per acre in a cropping system that includes grasses, legumes, or fully stocked, even-aged stand of trees at 60 years and grass-legume mixtures help to maintain fertility and tilth. 45,600 board feet per acre (Scribner rule) at 150 years. On Leaving crop, residue on or near the surface helps to the basis of a 50-year curve, the mean site index is 75. conserve moisture and control erosion. The main limitations affecting timber production are A tillage pan forms easily if the soil is tilled when wet. erosion, compaction, seedling mortality, and plant Chiseling or subsoiling breaks up the pan. Surface crusting competition. When timber is harvested, management that and compaction can be minimized by returning crop residue minimizes the risk of erosion is essential. Conventional to the soil. methods of harvesting timber generally are suitable, but the Seedbeds should be prepared on the contour or across soil may be compacted if it is moist the slope where practical. Proper stocking rates, pasture rotation, and restricted grazing during wet when heavy equipment is used. Puddling can occur when Included in this unit are small areas of Ruch, Vannoy, the soil is wet. Using low-pressure ground equipment and Voorhies soils; Tallowbox soils on the more sloping causes less damage to the soil and helps to maintain parts of the landscape and on convex slopes; poorly productivity. Compaction can be minimized by using drained soils near drainageways and on concave slopes; suitable methods of harvesting, laying out skid trails in and soils that are similar to the Shefflein soil but have advance, and harvesting timber when the soil is least bedrock at a depth of more than 60 inches. Also included susceptible to compaction. Ripping skid trails and landings are small areas of Shefflein soils that have slopes of less when the soil is dry can improve the growth of plants. than 20 or more than 35 percent. Included areas make up Erosion can be controlled by carefully planning the about 20 percent of the total acreage. construction and maintenance of logging roads, skid trails, Permeability is, moderately slow in the Shefflein soil. and landings. Seeding, mulching, and benching areas that Available water capacity is about 8 inches. The effective have been cut and filled also help to control erosion. Skid rooting depth is 40 to 60 inches. Runoff is medium, and the trails and unsurfaced roads may be impassable during hazard of water erosion is high. rainy periods. Logging roads require suitable surfacing for This unit is used for timber production and wildlife year-round use. habitat. It is suited to the production of Douglas fir and A high temperature in the surface layer and an ponderosa pine. Other species that grow on this unit include insufficient moisture supply in summer increase the incense cedar, sugar pine, and Pacific madrone. The seedling mortality rate. To compensate for the expected understory vegetation includes deerbrush, tall Oregongrape, high mortality rate, the larger seedlings or a greater number and western fescue. of seedlings should be planted. When the timber is On the basis of a 100-year site curve, the mean site harvested, leaving some of the larger trees unharvested index for Douglas fir is 110. The yield at culmination of the provides shade for seedlings. Reforestation can be mean annual increment is 5,880 cubic feet per acre in a accomplished by planting Douglas fir and ponderosa pine fully stocked, even-aged stand of trees at 60 years and seedlings. 48,300 board feet per acre (Scribner rule) at 140 years. On Undesirable plants limit natural or artificial the basis of a 50-year curve, the mean site index is 80. reforestation unless intensive site preparation and On the basis of a 100-year site curve, the mean site maintenance measures are applied. Mulching around index for ponderosa pine is 115. The yield at culmination of seedlings helps to maintain the moisture supply in the mean annual increment is 5,280 cubic feet per acre in summer and minimizes competition from undesirable a fully stocked, even-aged stand of trees at 40 years and plants. 56,780 board feet per acre (Scribner rule) at 110 years. Increased erosion, loss of plant nutrients, and water The main limitations affecting timber production are repellency are likely to result from fires of moderate erosion, compaction, plant competition, and seedling intensity. mortality. When timber is harvested, management that The vegetative site is Douglas Fir-Mixed Pine-Fescue minimizes the risk of erosion is essential. Wheeled and Forest. tracked logging equipment can be used in the less sloping areas, but cable yarding generally is safer in the more 165E-Shefflein loam, 20 to 35 percent north slopes. sloping areas and results in less surface disturbance. Using This deep, well drained soil is on hillslopes. It formed in standard wheeled and tracked equipment when the soil is colluvium and residuum derived from granitic rock. moist causes rutting and compaction. Puddling can occur Elevation is 1,000 to 4,000 feet. The mean annual when the soil is wet. Using low-pressure ground equipment precipitation is 25 to 40 inches, the mean annual causes less damage to the soil and helps to maintain temperature is 46 to 54 degrees F, and the average productivity. Compaction can be minimized by using suitable frost-free period is 100 to 160 days. The native vegetation methods of harvesting, laying out skid trails in advance, and is mainly conifers and hardwoods and an understory of harvesting timber when the soil is least susceptible to grasses, shrubs, and forbs. compaction. Ripping skid trails and landings when the soil is Typically, the surface layer is dark brown loam about 4 dry can improve the growth of plants. inches thick. The next layer is reddish brown loam about 6 Properly designed road drainage systems that include inches thick. The upper 30 inches of the subsoil is reddish carefully located culverts help to control erosion. Areas that brown clay loam. The lower 16 inches is reddish brown have been cut and filled are easily eroded sandy clay loam. Weathered bedrock is at a depth of about 56 inches. The depth to bedrock ranges from 40 to 60 inches. In some areas the surface layer is sandy loam or clay loam. Figure 11.-Severely eroded roadcut in an area of Shefflein loam, 20 to 35 percent north slopes.

unless they are treated (fig. 11). Seeding, mulching, and reforestation unless intensive site preparation and benching these areas help to control erosion. Steep yarding maintenance measures are applied. Reforestation can be paths, skid trails, and firebreaks are subject to rilling and accomplished by planting Douglas fir and ponderosa pine gullying unless they are protected by a plant cover or seedlings. Mulching around seedlings helps to maintain the adequate water bars, or both. Cutbanks occasionally slump moisture supply in summer and minimizes competition from when the soil is saturated. undesirable plants. This unit is subject to slumping, especially in areas A high temperature in the surface layer and an adjacent to drainageways. Road failure and landslides are insufficient moisture supply in summer increase the likely to occur after road construction and clearcutting. Skid seedling mortality rate. To compensate for the expected trails and unsurfaced roads may be impassable during high mortality rate, the larger seedlings or a greater number rainy periods. Logging roads require suitable surfacing for of seedlings should be planted. When the timber is year-round use. harvested, leaving some of the larger trees unharvested Undesirable plants limit natural or artificial provides shade for seedlings. Increased erosion, loss of plant nutrients, and water years. On the basis of a 50-year curve, the mean site repellency are likely to result from fires of moderate index is 70. intensity. The main limitations affecting timber production are The vegetative site is Douglas Fir-Mixed Pine-Fescue erosion, compaction, seedling mortality, and plant Forest. competition. When timber is harvested, management that minimizes the risk of erosion is essential. Wheeled and 166E-Shefflein loam, 20 to 35 percent south slopes. tracked logging equipment can be used in the less sloping This deep, well drained soil is on hillslopes. It formed in areas, but cable yarding generally is safer in the more colluvium and residuum derived from granitic rock. sloping areas and results in less surface disturbance. Using Elevation is 1,000 to 4,000 feet. The mean annual standard wheeled and tracked equipment when the soil is precipitation is 25 to 40 inches, the mean annual moist causes rutting and compaction. Puddling can occur temperature is 46 to 54 degrees F, and the average when the soil is wet. Using low-pressure ground equipment frost-free period is 100 to 160 days. The native vegetation causes less damage to the soil and helps to maintain is mainly conifers and hardwoods and an understory of productivity. Compaction can be minimized by using grasses, shrubs, and forbs. suitable methods of harvesting, laying out skid trails in Typically, the surface layer is dark brown loam about 4 advance, and harvesting timber when the soil is least inches thick. The next layer is reddish brown loam about 6 susceptible to compaction. Ripping skid trails and landings inches thick. The upper 30 inches of the subsoil is reddish when the soil is dry can improve the growth of plants. brown clay loam. The lower 16 inches is reddish brown Properly designed road drainage systems that include sandy clay loam. Weathered bedrock is at a depth of about carefully located culverts help to control erosion. Areas that 56 inches. The depth to bedrock ranges from 40 to 60 have been cut and filled are easily eroded unless they are inches. In some areas the surface layer is sandy loam or treated. Seeding, mulching, and benching these areas help clay loam or is stony. to control erosion. Steep yarding paths, skid trails, and Included in this unit are small areas of Ruch, Vannoy, firebreaks are subject to rilling and gullying unless they are and Voorhies soils; Tallowbox soils on the more sloping protected by a plant cover or adequate water bars, or both. parts of the landscape and on convex slopes; and soils that Cutbanks occasionally slump when the soil is saturated. are similar to the Shefflein soil but have bedrock at a depth This unit is subject to slumping, especially in areas of less than 40 or more than 60 inches. Also included are adjacent to drainageways. Road failure and landslides are small areas of poorly drained soils near drainageways and likely to occur after road construction and clearcutting. Skid on concave slopes and Shefflein soils that have slopes of trails and unsurfaced roads may be impassable during less than 20 or more than 35 percent. Included areas make rainy periods. Logging roads require suitable surfacing for up about 20 percent of the total acreage. year-round use. Permeability is moderately slow in the Shefflein soil. A high temperature in the surface layer and an Available water capacity is about 8 inches. The effective insufficient moisture supply in summer increase the seedling rooting depth is 40 to 60 inches. Runoff is medium, and the mortality rate. To compensate for the expected high hazard of water erosion is high. mortality rate, the larger seedlings or a greater number of This unit is used for timber production and wildlife seedlings should be planted. When the timber is harvested, habitat. It is suited to the production of ponderosa pine and leaving some of the larger trees unharvested provides Douglas fir. Other species that grow on this unit include shade for seedlings. The seedling mortality rate also can be incense cedar, sugar pine, and Pacific madrone. The reduced by providing artificial shade for seedlings. understory vegetation includes deerbrush, tall Oregongrape, Reforestation can be accomplished by planting Douglas fir and Idaho fescue. and ponderosa pine seedlings. On the basis of a 100-year site curve, the mean site Undesirable plants limit natural or artificial reforestation index for ponderosa pine is 100. The yield at culmination unless intensive site preparation and maintenance of the mean annual increment is 4,080 cubic feet per acre measures are applied (fig. 12). Mulching around seedlings in a fully stocked, even-aged stand of trees at 40 years helps to maintain the moisture supply in summer and and 44,640 board feet per acre (Scribner rule) at 120 minimizes competition from undesirable plants. years. Increased erosion, loss of plant nutrients, and water On the basis of a 100-year site curve, the mean site repellency are likely to result from fires of moderate index for Douglas fir is 100. The yield at culmination of the intensity. mean annual increment is 5,040 cubic feet per acre in a fully stocked, even-aged stand of trees at 60 years and 39,750 board feet per acre (Scribner rule) at 150 Figure 12.-Competing plants in a burned area of Shefflein loam, 20 to 35 percent south slopes. Whiteleaf manzanita is in the foreground.

The vegetative site is Mixed Pine-Douglas Fir-Fescue about 5 inches thick. The subsoil is very dark gray and Forest, Granitic. very dark grayish brown clay loam about 21 inches thick. The substratum to a depth of 60 inches is very dark 167B-Sibannac silt loam, 0 to 7 percent slopes. grayish brown and black clay loam. The depth to bedrock This very deep, poorly drained soil is in basins. It formed in is 60 inches or more. alluvium derived dominantly from andesite, tuff, and Included in this unit are small areas of Bybee, Farva, breccia. Elevation is 3,600 to 5,800 feet. The mean annual Kanutchan, Pinehurst, Rustlerpeak, Snowlin, and Tatouche precipitation is 30 to 40 inches, the mean annual soils; very poorly drained, organic soils; and Sibannac soils temperature is 40 to 45 degrees F, and the average that have slopes of more than 7 percent. Included areas frost-free period is less than 100 days. The native make up about 20 percent of the total acreage. vegetation is mainly grasses, sedges, and forbs. Permeability is moderately slow in the Sibannac soil. Typically, the surface layer is black silt loam about 6 Available water capacity is about 12 inches. The inches thick. The next layer is black silty clay loam effective rooting depth is limited by the water table, which is included are small areas of Siskiyou soils that have within a depth of 1 foot from January through June. Runoff slopes of less than 35 or more than 60 percent. Included is slow, and the hazard of water erosion is slight. areas make up about 20 percent of the total acreage. This unit is used for pasture and wildlife habitat. The Permeability is moderately rapid in the Siskiyou soil. main limitations affecting livestock grazing are the Available water capacity is about 3 inches. The effective seasonal wetness and compaction. The wetness limits the rooting depth is 20 to 40 inches. Runoff is rapid, and the choice of suitable forage plants and the period of cutting or hazard of water erosion is high. grazing and increases the risk of winterkill. This unit is used for timber production and wildlife If the pasture is overgrazed, the proportion of preferred habitat. It is suited to the production of Douglas fir. Other forage plants decreases and the proportion of less species that grow on this unit include ponderosa pine, preferred forage plants increases. The grazing system sugar pine, and Pacific dogwood. The understory should maintain the desired balance of species in the plant vegetation includes creambush oceanspray, California community. Proper stocking rates, pasture rotation, and hazel, and common snowberry. restricted grazing during wet periods help to keep pastures On the basis of a 100-year site curve, the mean site in good condition and protect the soil from erosion. Grazing index for Douglas fir is 115. The yield at culmination of the when the soil is wet results in compaction of the surface mean annual increment is 6,360 cubic feet per acre in a layer, poor tilth, and excessive runoff. Periodic mowing and fully stocked, even-aged stand of trees at 60 years and clipping help to maintain uniform plant growth, discourage 15,700 board feet per acre (Scribner rule) at 130 years. On selective grazing, and reduce the extent of clumpy growth. the basis of a 50-year curve, the mean site index is 85. Tufted hairgrass is the native plant preferred for The main limitations affecting timber production are the livestock grazing; however, this unit can be renovated and slope, erosion, compaction, plant competition, and forage production increased by seeding other suitable seedling mortality. Also, the bedrock restricts root growth. grasses. The plants selected for seeding should be those As a result, windthrow is a hazard. that are tolerant of a cold climate and wetness. Fertilizer is When timber is harvested, management that minimizes needed to ensure the optimum growth of grasses. the risk of erosion is essential. Wheeled and tracked Grasses respond to nitrogen. logging equipment can be used in the less sloping areas, The vegetative site is Wet Meadow. but cable yarding generally is safer and results in less surface disturbance. Using standard wheeled and tracked 168G-Siskiyou gravelly sandy loam, 35 to 60 percent equipment when the soil is moist causes rutting and north slopes. This moderately deep, somewhat excessively compaction. Puddling can occur when the soil is wet. Using drained soil is on hillslopes. It formed in colluvium derived low-pressure ground equipment causes less damage to the from granitic rock. Elevation is 1,200 to 4,000 feet. The soil and helps to maintain productivity. Compaction can be mean annual precipitation is 40 to 50 inches, the mean minimized by using suitable methods of harvesting, laying annual temperature is 45 to 52 degrees F, and the average out skid trails in advance, and harvesting timber when the frost-free period is 100 to 160 days. The native vegetation is soil is least susceptible to compaction. Ripping skid trails mainly conifers and hardwoods and an understory of and landings when the soil is dry can improve the growth of grasses, shrubs, and forbs. plants. Typically, the surface is covered with a layer of needles Properly designed road drainage systems that include and twigs about 1 inch thick. The surface layer is dark carefully located culverts help to control erosion. Areas that brown gravelly sandy loam about 9 inches thick. The have been cut and filled are easily eroded unless they are subsoil is olive brown sandy loam about 8 inches thick. The treated. Seeding, mulching, and benching these areas help substratum is grayish brown sandy loam about 18 inches to control erosion. Steep yarding paths, skid trails, and thick. Weathered bedrock is at a depth of about 35 inches. firebreaks are subject to rilling and gullying unless they are The depth to bedrock ranges from 20 to 40 inches. protected by a plant cover or adequate water bars, or both. Included in this unit are small areas of Beekman, Cutbanks occasionally slump when the soil is saturated. Colestine, Josephine, and Speaker soils; Rock outcrop; This unit is subject to slumping, especially in areas soils that are similar to the Siskiyou soil but have bedrock adjacent to drainageways. Road failure and landslides are at a depth of more than 40 inches; and, on ridges, soils that likely to occur after road construction and clearcutting. are similar to the Siskiyou soil but have bedrock at a depth Constructing logging roads on the steeper slopes can of less than 20 inches. Also result in a high risk of erosion. Building the roads at have bedrock within a depth of 20 inches. Also included are midslope requires extensive cutting and filling and removes small areas of Siskiyou soils that have slopes of less than land from production. Material that is discarded when the 35 or more than 60 percent. Included areas make up about roads are built can damage vegetation and is a potential 20 percent of the total acreage. source of sedimentation. If the material becomes saturated, Permeability is moderately rapid in the Siskiyou soil. avalanches of debris can occur. End hauling of the waste Available water capacity is about 3 inches. The effective material minimizes damage to the vegetation downslope rooting depth is 20 to 40 inches. Runoff is rapid, and the and reduces the risk of sedimentation. Skid trails and hazard of water erosion is high. unsurfaced roads may be impassable during rainy periods. This unit is used for timber production and wildlife Logging roads require suitable surfacing for year-round habitat. It is suited to the production of Douglas fir. Other use. species that grow on this unit include ponderosa pine, Undesirable plants limit natural or artificial reforestation sugar pine, and California black oak. The understory unless intensive site preparation and maintenance vegetation includes canyon live oak, deerbrush, and measures are applied. Reforestation can be accomplished western fescue. by planting Douglas fir and ponderosa pine seedlings. On the basis of a 100-year site curve, the mean site Mulching around seedlings helps to maintain the moisture index for Douglas fir is 110. The yield at culmination of the supply in summer and minimizes competition from mean annual increment is 5,880 cubic feet per acre in a undesirable plants. fully stocked, even-aged stand of trees at 60 years and A high temperature in the surface layer during summer 48,300 board feet per acre (Scribner rule) at 140 years. On and the low available water capacity increase the seedling the basis of a 50-year curve, the mean site index is 75. mortality rate. To compensate for the expected high The main limitations affecting timber production are the mortality rate, the larger seedlings or a greater number of slope, erosion, compaction, seedling mortality, and plant seedlings should be planted. When the timber is harvested, competition. Also, the bedrock restricts root growth. As a leaving some of the larger trees unharvested provides result, windthrow is a hazard. shade for seedlings. When timber is harvested, management that minimizes Increased erosion, loss of plant nutrients, and water the risk of erosion is essential. Wheeled and tracked logging repellency are likely to result from fires of moderate equipment can be used in the less sloping areas, but cable intensity. yarding generally is safer and results in less surface The vegetative site is Douglas Fir-Dogwood Forest, disturbance. Using standard wheeled and tracked Granitic. equipment when the soil is moist causes rutting and compaction. Puddling can occur when the soil is wet. Using 169G-Siskiyou gravelly sandy loam, 35 to 60 percent low-pressure ground equipment causes less damage to the south slopes. This moderately deep, somewhat soil and helps to maintain productivity. Compaction can be excessively drained soil is on hillslopes. It formed in minimized by using suitable methods of harvesting, laying colluvium derived from granitic rock. Elevation is 1,200 to out skid trails in advance, and harvesting timber when the 4,000 feet. The mean annual precipitation is 40 to 50 soil is least susceptible to compaction. Ripping skid trails inches, the mean annual temperature is 45 to 52 degrees F, and landings when the soil is dry can improve the growth of and the average frost-free period is 100 to 160 days. The plants. native vegetation is mainly conifers and hardwoods and an Properly designed road drainage systems that include understory of grasses, shrubs, and forbs. carefully located culverts help to control erosion. Areas that Typically, the surface is covered with a layer of needles have been cut and filled are easily eroded unless they are and twigs about 1 inch thick. The surface layer is dark treated. Seeding, mulching, and benching these areas help brown gravelly sandy loam about 9 inches thick. The to control erosion. Steep yarding paths, skid trails, and subsoil is olive brown sandy loam about 8 inches thick. The firebreaks are subject to rilling and gullying unless they are substratum is grayish brown sandy loam about 18 inches protected by a plant cover or adequate water bars, or both. thick. Weathered bedrock is at a depth of about 35 inches. Cutbanks occasionally stump when the soil is saturated. The depth to bedrock ranges from 20 to 40 inches. This unit is subject to slumping, especially in areas Included in this unit are small areas of Beekman, adjacent to drainageways. Road failure and landslides are Colestine, Josephine, and Speaker soils; Rock outcrop; likely to occur after road construction and clearcutting. soils that are similar to the Siskiyou soil but have bedrock Constructing logging roads on the steeper slopes can at a depth of more than 40 inches; and, on ridges, soils that are similar to the Siskiyou soil but result in a high risk of erosion. Building the roads at and on concave slopes; and soils that are similar to the midslope requires extensive cutting and filling and removes Skookum soil but have bedrock at a depth of more than 40 land from production. Material that is discarded when the inches. Also included are small areas of Skookum soils that roads are built can damage vegetation and is a potential have slopes of more than 12 percent. Included areas make source of sedimentation. If the material becomes saturated, up about 20 percent of the total acreage. avalanches of debris can occur. End hauling of the waste Permeability is slow in the Skookum soil. Available water material minimizes damage to the vegetation downslope capacity is about 2 inches. The effective rooting depth is 20 and reduces the risk of sedimentation. Skid trails and to 40 inches. Runoff is slow, and the hazard of water unsurfaced roads may be impassable during rainy periods. erosion is slight. Logging roads require suitable surfacing for year-round This unit is used for livestock grazing and wildlife habitat. use. The main limitations affecting livestock grazing are A high temperature in the surface layer during summer compaction, cobbles and stones on the surface, and and the low available water capacity increase the seedling droughtiness. The vegetation suitable for grazing includes mortality rate. To compensate for the expected high Idaho fescue, bluebunch wheatgrass, and pine bluegrass. If mortality rate, the larger seedlings or a greater number of the range is overgrazed, the proportion of preferred forage seedlings should be planted. When the timber is harvested, plants decreases and the proportion of less preferred forage leaving some of the larger trees unharvested provides plants increases. Grazing should be delayed until the more shade for seedlings. The seedling mortality rate also can be desirable forage plants have achieved enough growth to reduced by providing artificial shade for seedlings. withstand grazing pressure and the soil is firm enough to Reforestation can be accomplished by planting Douglas fir withstand trampling by livestock. and ponderosa pine seedlings. Suitable management practices on this unit include Undesirable plants limit natural or artificial proper grazing use, deferred grazing, rotation grazing, and reforestation unless intensive site preparation and brush control. Areas that support a large amount of maintenance measures are applied. Mulching around competing vegetation can be improved by chemical or seedlings helps to maintain the moisture supply in mechanical treatment. The use of ground equipment is summer and minimizes competition from undesirable limited in many areas by the cobbles and stones on the plants. surface. Increased erosion, loss of plant nutrients, and water Range seeding is suitable if the site is in poor condition. repellency are likely to result from fires of moderate The main limitations are droughtiness and the cobbles and intensity. stones on the surface. The plants selected for seeding The vegetative site is Douglas Fir-Black Oak Forest. should be those that meet the seasonal requirements of livestock or wildlife, or both. 170C-Skookum very cobbly loam, 1 to 12 percent This unit is limited as a site for livestock watering slopes. This moderately deep, well drained soil is on ponds and other water impoundments because of the hillslopes. It formed in residuum and colluvium derived slope and the depth to bedrock. dominantly from andesite, tuff, and breccia. Elevation is The vegetative site is Droughty Slopes, 20- to 30- 2,000 to 4,000 feet. The mean annual precipitation is 20 to inch precipitation zone. 35 inches, the mean annual temperature is 45 to 52 degrees F, and the average frost-free period is 100 to 150 days. The 171E-Skookum-Bogus complex, 12 to 35 percent native vegetation is mainly grasses, shrubs, and forbs and a north slopes. This map unit is on hillslopes. Elevation is few scattered hardwoods. 3,000 to 4,400 feet. The mean annual precipitation is 18 to Typically, the surface layer is very dark brown very 25 inches, the mean annual temperature is 45 to 50 cobbly loam about 3 inches thick. The next layer is very degrees F, and the average frost-free period is 100 to 150 dark grayish brown very cobbly loam about 5 inches thick. days. The native vegetation on the Skookum soil is mainly The upper 8 inches of the subsoil is very dark grayish grasses, shrubs, and forbs and a few scattered hardwoods. brown very cobbly clay loam. The lower 12 inches is dark That on the Bogus soil is mainly conifers and hardwoods brown very cobbly and extremely cobbly clay. Bedrock is at and an understory of grasses, shrubs, and forbs. a depth of about 28 inches. The depth to bedrock ranges This unit is about 50 percent Skookum soil and 30 from 20 to 40 inches. In some areas the surface layer is percent Bogus soil. The components of this unit occur as stony. areas so intricately intermingled that mapping them Included in this unit are small areas of Lorella, separately was not practical at the scale used. McMullin, Randcore, and Shoat soils; Carney and Medco Included in this unit are small areas of Heppsie soils, soils on concave slopes; McNull soils on north-facing slopes; poorly drained soils near drainageways Lorella soils and Rock outcrop on convex slopes, Carney less preferred forage plants increases. Grazing should be soils on concave slopes, and poorly drained soils near delayed until the more desirable forage plants have drainageways and on concave slopes. Also included are achieved enough growth to withstand grazing pressure small areas of soils that are similar to the Bogus soil but and the soils are firm enough to withstand trampling by have bedrock within a depth of 60 inches, soils that are livestock. similar to the Skookum soil but have bedrock at a depth of Suitable management practices on this unit include more than 40 inches, and Bogus and Skookum soils that proper grazing use, deferred grazing, rotation grazing, and have slopes of less than 12. or more than 35 percent. brush control. Areas that support a large amount of Included areas make up about 20 percent of the total competing vegetation can be improved by chemical or acreage. mechanical treatment. The use of ground equipment is The Skookum soil is moderately deep and well drained. It limited by the cobbles and stones on the surface of the formed in residuum and colluvium derived dominantly from Skookum soil and the slope. andesite, tuff, and breccia. Typically, the surface layer is This unit is poorly suited to range seeding. The main very dark brown very cobbly loam about 3 inches thick. The limitations are droughtiness and the cobbles and stones on next layer is very dark grayish brown very cobbly loam about the surface of the Skookum soil. The plants selected for 5 inches thick. The upper 8 inches of the subsoil is very dark seeding should be those that meet the seasonal grayish brown very cobbly clay loam. The lower 12 inches is requirements of livestock or wildlife, or both. dark brown very cobbly and extremely cobbly clay. Bedrock This unit is limited as a site for livestock watering is at a depth of about 28 inches. The depth to bedrock ponds and other water impoundments because of the ranges from 20 to 40 inches. In some areas the surface slope of both soils and the depth to bedrock in the layer is stony. Skookum soil. Permeability is slow in the Skookum soil. Available The Bogus soil is suited to the production of Douglas fir water capacity is about 2 inches. The effective rooting and ponderosa pine. Other species that grow on this unit depth is 20 to 40 inches. Runoff is medium, and the include incense cedar, sugar pine, and California black oak. hazard of water erosion is moderate. The understory vegetation includes tall Oregongrape, The Bogus soil is very deep and well drained. It formed in common snowberry, and western fescue. residuum and colluvium derived dominantly from andesite, On the basis of a 100-year site curve, the mean site tuff, and breccia. Typically, the surface is covered with a index for Douglas fir is 100 on the Bogus soil. The yield at layer of needles, leaves, and twigs about 1 inch thick. The culmination of the mean annual increment is 5,040 cubic surface layer is black very gravelly loam about 7 inches feet per acre in a fully stocked, even-aged stand of trees at thick. The next layer is very dark grayish brown very gravelly 60 years and 39,750 board feet per acre (Scribner rule) at loam about 8 inches thick. The upper 6 inches of the subsoil 150 years. On the basis of a 50-year curve, the mean site is dark brown gravelly clay loam. The lower 44 inches is index is 70. dark yellowish brown and dark brown clay loam. The depth On the basis of a 100-year site curve, the mean site to bedrock is 60 inches or more. In some areas the surface index for ponderosa pine is 90 on the Bogus soil. The yield layer is stony. at culmination of the mean annual increment is 3,400 Permeability is slow in the Bogus soil. Available water cubic feet per acre in a fully stocked, even-aged stand of capacity is about 8 inches. The effective rooting depth is trees at 40 years and 37,960 board feet per acre (Scribner 60 inches or more. Runoff is medium, and the hazard of rule) at 130 years. water erosion is moderate. The main limitations affecting timber production on the This unit is used mainly for livestock grazing or wildlife Bogus soil are erosion, compaction, seedling mortality, and habitat. The Bogus soil also is used for timber production. plant competition. Wheeled and tracked logging equipment The main limitations affecting livestock grazing are can be used in the less sloping areas, but cable yarding compaction, erosion, and the slope. The Skookum soil also generally is safer in the more sloping areas and results in is limited by cobbles and stones on the surface and by less surface disturbance. Using standard wheeled and droughtiness. The vegetation suitable for grazing includes tracked equipment when the soil is moist causes rutting Idaho fescue, bluebunch wheatgrass, and pine bluegrass and compaction. If the soil is excessively disturbed when on the Skookum soil and western fescue, mountain brome, timber is harvested or logging roads are built, a larger and tall trisetum on the Bogus soil. If the range is number of rock fragments is left on the surface. Puddling overgrazed, the proportion of preferred forage plants can occur when the soil is wet. Using low-pressure ground decreases and the proportion of equipment causes less damage to the soil and helps to maintain productivity. Compaction can be minimized by using suitable methods of harvesting, laying out skid trails in advance, and harvesting timber when the soil is included are small areas of soils that are similar to the least susceptible to compaction. Ripping skid trails and Bogus soil but have bedrock within a depth of 60 inches, landings when the soil is dry can improve the growth of soils that are similar to the Skookum soil but have bedrock plants. at a depth of more than 40 inches, and Bogus and Properly designed road drainage systems that include Skookum soils that have slopes of less than 12 or more carefully located culverts help to control erosion. Seeding, than 35 percent. Included areas make up about 20 percent mulching, and benching areas that have been cut and filled of the total acreage. also help to control erosion. Steep yarding paths, skid trails, The Skookum soil is moderately deep and well drained. It and firebreaks are subject to rilling and gullying unless they formed in residuum and colluvium derived dominantly from are protected by a plant cover or adequate water bars, or andesite, tuff, and breccia. Typically, the surface layer is both. Skid trails and unsurfaced roads may be impassable very dark brown very cobbly loam about 3 inches thick. The during rainy periods. Logging roads require suitable next layer is very dark grayish brown very cobbly loam surfacing for year-round use. about 5 inches thick. The upper 8 inches of the subsoil is A high temperature in the surface layer and an very dark grayish brown very cobbly clay loam. The lower insufficient moisture supply in summer increase the 12 inches is dark brown very cobbly and extremely cobbly seedling mortality rate. The large number of rock fragments clay. Bedrock is at a depth of about 28 inches. The depth to in some areas also increases the seedling mortality rate. To bedrock ranges from 20 to 40 inches. In some areas the compensate for the expected high mortality rate, the larger surface layer is stony. seedlings or a greater number of seedlings should be Permeability is slow in the Skookum soil. Available planted. When the timber is harvested, leaving some of the water capacity is about 2 inches. The effective rooting larger trees unharvested provides shade for seedlings. depth is 20 to 40 inches. Runoff is medium, and the Reforestation can be accomplished by planting ponderosa hazard of water erosion is moderate. pine and Douglas fir seedlings. The Bogus soil is very deep and well drained. It formed in Undesirable plants limit natural or artificial residuum and colluvium derived dominantly from andesite, reforestation unless intensive site preparation and tuff, and breccia. Typically, the surface is covered with a maintenance measures are applied. Mulching around layer of needles, leaves, and twigs about 1 inch thick. The seedlings helps to maintain the moisture supply in surface layer is black very gravelly loam about 7 inches summer and minimizes competition from undesirable thick. The next layer is very dark grayish brown very gravelly plants. loam about 8 inches thick. The upper 6 inches of the subsoil The vegetative site in areas of the Skookum soil is is dark brown gravelly clay loam. The lower 44 inches is Droughty Slopes, 20- to 30-inch precipitation zone, and the dark yellowish brown and dark brown clay loam. The depth one in areas of the Bogus soil is Douglas Fir-Mixed to bedrock is 60 inches or more. In some areas the surface Pine-Sedge Forest. layer is stony. Permeability is slow in the Bogus soil. Available water 172E-Skookum-Bogus complex, 12 to 35 percent capacity is about 8 inches. The effective rooting depth is south slopes. This map unit is on hillslopes. Elevation is 60 inches or more. Runoff is medium, and the hazard of 3,000 to 4,400 feet. The mean annual precipitation is 18 to water erosion is moderate. 25 inches, the mean annual temperature is 45 to 50 This unit is used mainly for livestock grazing or wildlife degrees F, and the average frost-free period is 100 to 150 habitat. The Bogus soil also is used for timber production. days. The native vegetation on the Skookum soil is mainly The main limitations affecting livestock grazing are grasses, shrubs, and forbs and a few scattered hardwoods. compaction, erosion, and the slope. The Skookum soil also That on the Bogus soil is mainly conifers and hardwoods is limited by cobbles and stones on the surface and by and an understory of grasses, shrubs, and forbs. droughtiness. The vegetation suitable for grazing includes This unit is about 55 percent Skookum soil and 25 Idaho fescue, bluebunch wheatgrass, and pine bluegrass percent Bogus soil. The components of this unit occur as on the Skookum soil and western fescue, mountain brome, areas so intricately intermingled that mapping them and tall trisetum on the Bogus soil. If the range is separately was not practical at the scale used. overgrazed, the proportion of preferred forage plants Included in this unit are small areas of Heppsie soils, decreases and the proportion of less preferred forage Lorella soils and Rock outcrop on convex slopes, Carney plants increases. Grazing should be delayed until the more soils on concave slopes, and poorly drained soils near desirable forage plants have achieved enough growth to drainageways and on concave slopes. Also withstand grazing pressure and the soils are firm enough to withstand trampling by landings when the soil is dry can improve the growth of livestock. plants. Suitable management practices on this unit include Properly designed road drainage systems that include proper grazing use, deferred grazing, rotation grazing, and carefully located culverts help to control erosion. Seeding, brush control. Areas that support a large amount of mulching, and benching areas that have been cut and filled competing vegetation can be improved by chemical or also help to control erosion. Steep yarding paths, skid trails, mechanical treatment. The use of ground equipment on the and firebreaks are subject to rilling and gullying unless they Skookum soil is limited by the cobbles and stones on the are protected by a plant cover or adequate water bars, or surface and the slope. both. Skid trails and unsurfaced roads may be impassable This unit is poorly suited to range seeding. The main during rainy periods. Logging roads require suitable limitations are droughtiness and the cobbles and stones on surfacing for year-round use. the surface of the Skookum soil. The plants selected for A high temperature in the surface layer and an seeding should be those that meet the seasonal insufficient moisture supply in summer increase the seedling requirements of livestock or wildlife, or both. mortality rate. The large number of rock fragments in some This unit is limited as a site for livestock watering areas also increases the seedling mortality rate. To ponds and other water impoundments because of the compensate for the expected high mortality rate, the larger slope of both soils and the depth to bedrock in the seedlings or a greater number of seedlings should be Skookum soil. planted. When the timber is harvested, leaving some of the The Bogus soil is suited to the production of Douglas fir larger trees unharvested provides shade for seedlings. and ponderosa pine. Other species that grow on this unit Reforestation can be accomplished by planting ponderosa include incense cedar, sugar pine, and California black oak. pine and Douglas fir seedlings. The understory vegetation includes tall Oregongrape, Undesirable plants limit natural or artificial common snowberry, and western fescue. reforestation unless intensive site preparation and On the basis of a 100-year site curve, the mean site maintenance measures are applied. Mulching around index for Douglas fir is 90 on the Bogus soil. The yield at seedlings helps to maintain the moisture supply in culmination of the mean annual increment is 4,200 cubic summer and minimizes competition from undesirable feet per acre in a fully stocked, even-aged stand of trees at plants. 60 years and 31,840 board feet per acre (Scribner rule) at The vegetative site in areas of the Skookum soil is 160 years. On the basis of a 50-year curve, the mean site Droughty Slopes, 20- to 30-inch precipitation zone, and the index is 65. one in areas of the Bogus soil is Douglas Fir-Mixed On the basis of a 100-year site curve, the mean site Pine-Sedge Forest. index for ponderosa pine is 85 on the Bogus soil. The yield at culmination of the mean annual increment is 3,080 cubic 173D-Skookum-Rock outcrop-McMullin complex, 1 feet per acre in a fully stocked, even-aged stand of trees at to 20 percent slopes. This map unit is on plateaus. 40 years and 38,700 board feet per acre (Scribner rule) at Elevation is 2,000 to 4,000 feet. The mean annual 150 years. precipitation is 20 to 35 inches, the mean annual The main limitations affecting timber production on the temperature is 45 to 52 degrees F, and the average Bogus soil are erosion, compaction, seedling mortality, and frost-free period is 100 to 150 days. The native vegetation plant competition. Wheeled and tracked logging equipment is mainly grasses, shrubs, and forbs and a few scattered can be used in the less sloping areas, but cable yarding hardwoods. generally is safer in the more sloping areas and results in This unit is about 60 percent Skookum soil, 15 less surface disturbance. Using standard wheeled and percent Rock outcrop, and 15 percent McMullin soil. The tracked equipment when the soil is moist causes rutting and components of this unit occur as areas so intricately compaction. If the soil is excessively disturbed when timber intermingled that mapping them separately was not is harvested or logging roads are built, a larger number of practical at the scale used. rock fragments is left on the surface. Puddling can occur Included in this unit are small areas of Lorella, Randcore, when the soil is wet. Using low-pressure ground equipment and Shoat soils; Carney and Medco soils on concave causes less damage to the soil and helps to maintain slopes; McNull soils on north-facing slopes; poorly drained productivity. Compaction can be minimized by using soils near drainageways and on concave slopes; and soils suitable methods of harvesting, laying out skid trails in that are similar to the Skookum soil but have bedrock at a advance, and harvesting timber when the soil is least depth of more than 40 inches. Also included are small areas susceptible to compaction. Ripping skid trails and of Skookum and McMullin soils that have slopes of more than 20 percent. Included limitations are the depth to bedrock in the McMullin soil, areas make up about 10 percent of the total acreage. droughtiness, the cobbles and stones on the surface, and The Skookum soil is moderately deep and well drained. It the Rock outcrop. The plants selected for seeding should be formed in residuum and colluvium derived dominantly from those that meet the seasonal requirements of livestock or andesite, tuff, and breccia. Typically, the surface layer is wildlife, or both. very dark brown very cobbly loam about 3 inches thick. The This unit is limited as a site for livestock watering next layer is very dark grayish brown very cobbly loam about ponds and other water impoundments because of the 5 inches thick. The upper 8 inches of the subsoil is very dark slope and the depth to bedrock. grayish brown very cobbly clay loam. The lower 12 inches is The vegetative site in areas of the Skookum soil is dark brown very cobbly and extremely cobbly clay. Bedrock Droughty Slopes, 20- to 30-inch precipitation zone, anal the is at a depth of about 28 inches. The depth to bedrock one in areas of the McMullin soil is Loamy Shrub Scabland, ranges from 20 to 40 inches. In some areas the surface 18- to 35-inch precipitation zone. layer is stony. Permeability is slow in the Skookum soil. Available water 173F-Skookum-Rock outcrop-McMullin complex, 20 capacity is about 2 inches. The effective rooting depth is 20 to 50 percent slopes. This map unit is on hillslopes. to 40 inches. Runoff is slow or medium, and the hazard of Elevation is 2,000 to 4,700 feet. The mean annual water erosion is slight or moderate. precipitation is 20 to 35 inches, the mean annual Rock outcrop consists of areas of exposed bedrock. temperature is 45 to 52 degrees F, and the average Runoff is very rapid in these areas. frost-free period is 100 to 150 days. The native vegetation The McMullin soil is shallow and well drained. It formed is mainly grasses, shrubs, and forbs and a few scattered in colluvium derived dominantly from andesite, tuff, and hardwoods. breccia. Typically, the surface layer is dark reddish brown This unit is about 55 percent Skookum soil, 20 gravelly loam about 7 inches thick. The subsoil is dark percent Rock outcrop, and 15 percent McMullin soil. The reddish brown gravelly clay loam about 10 inches thick. components of this unit occur as areas so intricately Bedrock is at a depth of about 17 inches. The depth to intermingled that mapping them separately was not bedrock ranges from 12 to 20 inches. In some areas the practical at the scale used. surface layer is stony. Included in this unit are small areas of Heppsie and Permeability is moderate in the McMullin soil. Available Lorella soils, Carney and Medco soils on concave slopes, water capacity is about 2 inches. The effective rooting depth McNull soils on north-facing slopes, and poorly drained soils is 12 to 20 inches. Runoff is slow or medium, and the hazard near drainageways and on concave slopes. Also included of water erosion is slight or moderate. are small areas of soils that are similar to the Skookum soil This unit is used for livestock grazing and wildlife habitat. but have bedrock at a depth of more than 40 inches, soils The main limitations affecting livestock grazing are that are similar to the McMullin soil but have bedrock at a compaction, erosion, the Rock outcrop, cobbles and stones depth of less than 12 or more than 20 inches, and Skookum on the surface, and droughtiness. The McMullin soil also is and McMullin soils that have slopes of less than 20 or more limited by the depth to bedrock. The vegetation suitable for than 50 percent. Included areas make up about 10 percent grazing includes Idaho fescue, bluebunch wheatgrass, and of the total acreage. pine bluegrass. If the range is overgrazed, the proportion of The Skookum soil is moderately deep and well drained. It preferred forage plants decreases and the proportion of less formed in colluvium derived dominantly from andesite, tuff, preferred forage plants increases. Grazing should be and breccia. Typically, the surface layer is very dark brown delayed until the more desirable forage plants have very cobbly loam about 3 inches thick. The next layer is very achieved enough growth to withstand grazing pressure and dark grayish brown very cobbly loam about 5 inches thick. the soils are firm enough to withstand trampling by livestock. The upper 8 inches of the subsoil is very dark grayish brown Suitable management practices on this unit include very cobbly clay loam. The lower 12 inches is dark brown proper grazing use, deferred grazing, rotation grazing, and very cobbly and extremely cobbly clay. Bedrock is at a depth brush control. Areas that support a large amount of of about 28 inches. The depth to bedrock ranges from 20 to competing vegetation can be improved by chemical or 40 inches. In some areas the surface layer is stony. mechanical treatment. The use of ground equipment is not Permeability is slow in the Skookum soil. Available practical because of the cobbles and stones on the surface water capacity is about 2 inches. The effective rooting and the Rock outcrop. depth is 20 to 40 inches. Runoff is medium or rapid, and This unit is poorly suited to range seeding. The main the hazard of water erosion is moderate or high. Rock outcrop consists of areas of exposed bedrock. 174G-Skookum-Rock outcrop-Rubble land complex, Runoff is very rapid in these areas. 35 to 70 percent slopes. This map unit is on hillslopes (fig. The McMullin soil is shallow and well drained. It formed 13). Elevation is 2,800 to 4,800 feet. The mean annual in colluvium derived dominantly from andesite, tuff, and precipitation is 18 to 35 inches, the mean annual breccia. Typically, the surface layer is dark reddish brown temperature is 45 to 52 degrees F, and the average gravelly loam about 7 inches thick. The subsoil is dark frost-free period is 100 to 150 days. The native vegetation is reddish brown gravelly clay loam about 10 inches thick. mainly grasses, shrubs, and forbs and a few scattered Bedrock is at a depth of about 17 inches. The depth to hardwoods. bedrock ranges from 12 to 20 inches. In some areas the This unit is about 40 percent Skookum soil, 20 percent surface layer is stony. Rock outcrop, and 10 percent Rubble land. The Permeability is moderate in the McMullin soil. Available components of this unit occur as areas so intricately water capacity is about 2 inches. The effective rooting depth intermingled that mapping them separately was not is 12 to 20 inches. Runoff is medium or rapid, and the practical at the scale used. hazard of water erosion is moderate or high. Included in this unit are small areas of Heppsie and This unit is used for livestock grazing and wildlife habitat. Lorella soils, Carney soils on concave slopes, Bogus and The main limitations affecting livestock grazing are the McNull soils on north-facing slopes, poorly drained soils slope, erosion, compaction, the Rock outcrop, cobbles and near drainageways and on concave slopes, and soils that stones on the surface, and droughtiness. The McMullin soil are similar to the Skookum soil but have bedrock at a depth also is limited by the depth to bedrock. The vegetation of more than 40 inches. Also included are small areas suitable for grazing includes Idaho fescue, bluebunch where slopes are less than 35 or more than 70 percent. wheatgrass, and pine bluegrass. If the range is overgrazed, Included areas make up about 30 percent of the total the proportion of preferred forage plants decreases and the acreage. proportion of less preferred forage plants increases. The Skookum soil is moderately deep and well drained. It Grazing should be delayed until the more desirable forage formed in residuum and colluvium derived dominantly from plants have achieved enough growth to withstand grazing andesite, tuff, and breccia. Typically, the surface layer is pressure and the soils are firm enough to withstand very dark brown very cobbly loam about 3 inches thick. The trampling by livestock. next layer is very dark grayish brown very cobbly loam about Suitable management practices on this unit include 5 inches thick. The upper 8 inches of the subsoil is very dark proper grazing use, deferred grazing, rotation grazing, and grayish brown very cobbly clay loam. The lower 12 inches is brush control. Areas that support a large amount of dark brown very cobbly and extremely cobbly clay. Bedrock competing vegetation can be improved by chemical or is at a depth of about 28 inches. The depth to bedrock mechanical treatment. The use of ground equipment is not ranges from 20 to 40 inches. In some areas the surface practical because of the cobbles and stones on the surface, layer is stony. the Rock outcrop, and the slope. Permeability is slow in the Skookum soil. Available This unit is poorly suited to range seeding. The main water capacity is about 2 inches. The effective rooting limitations are the slope, droughtiness, the Rock outcrop, depth is 20 to 40 inches. Runoff is rapid, and the hazard the cobbles and stones on the surface, and the depth to of water erosion is high. bedrock in the McMullin soil. The plants selected for seeding Rock outcrop consists of areas of exposed bedrock. should be those that meet the seasonal requirements of Rubble land consists of areas of stones and boulders. livestock or wildlife, or both. Runoff is very rapid in areas of both the Rock outcrop and The slope and the Rock outcrop limit access by the Rubble land. livestock. As a result, the less sloping areas tend to be This unit is used for livestock grazing and wildlife habitat. overgrazed. Constructing trails or walkways allows The main limitations affecting livestock grazing are the livestock to graze in areas where access is limited. slope, erosion, compaction, the Rock outcrop and Rubble This unit is limited as a site for livestock watering land, cobbles and stones on the surface, and droughtiness. ponds and other water impoundments because of the Because of the slope, the Rock outcrop, and the Rubble slope and the depth to bedrock. land, areas of this unit can hinder livestock movement. The The vegetative site in areas of the Skookum soil is vegetation suitable for grazing includes Idaho fescue, Droughty Slopes, 20- to 30-inch precipitation zone, and the bluebunch wheatgrass, and pine bluegrass. If the range is one in areas of the McMullin soil is Loamy Shrub Scabland, overgrazed, the proportion of preferred forage plants 18- to 35-inch precipitation zone. decreases and the proportion of less preferred forage plants increases. Grazing should be delayed until the more desirable Figure 13. -Typical area of Skookum-Rock outcrop-Rubble land complex, 35 to 70 percent slopes.

forage plants have achieved enough growth to withstand Rubble land. The plants selected for seeding should be grazing pressure and the soil is firm enough to withstand those that. meet the seasonal requirements of livestock or trampling by livestock. wildlife, or both. Suitable management practices on this unit include The slope and the Rock outcrop and Rubble land limit proper grazing use, deferred grazing, rotation grazing, and access by livestock. As a result, the less sloping areas tend to brush control. Areas that support a large amount of be overgrazed. Constructing trails or walkways allows competing vegetation can be improved by chemical or livestock to graze in areas where access is limited. mechanical treatment. The use of ground equipment is not This unit is limited as a site for livestock watering practical because of the cobbles and stones on the surface, ponds and other water impoundments because of the the Rock outcrop, the Rubble land, and the slope. slope and the depth to bedrock. This unit is poorly suited to range seeding. The main The vegetative site is Droughty Slopes, 20- to 30- limitations are the slope, droughtiness, the cobbles and inch precipitation zone. stones on the surface, and the Rock outcrop and 175F-Snowbrier gravelly loam, 25 to 50 percent north excessively disturbed when timber is harvested or logging slopes. This moderately deep, well drained soil is on roads are built, a larger number of rock fragments is left on hillslopes. It formed in colluvium derived dominantly from the surface. Using standard wheeled and tracked schist. Elevation is 3,600 to 4,700 feet. The mean annual equipment when the soil is moist causes rutting and precipitation is 40 to 60 inches, the mean annual compaction. Puddling can occur when the soil is wet. Using temperature is 40 to 45 degrees F, and the average low-pressure ground equipment causes less damage to the frost-free period is less than 100 days. The native soil and helps to maintain productivity. Compaction can be vegetation is mainly conifers and an understory of grasses, minimized by using suitable methods of harvesting, laying shrubs, and forbs. out skid trails in advance, and harvesting timber when the Typically, the surface is covered with a layer of needles, soil is least susceptible to compaction. Ripping skid trails leaves, and twigs about 1 inch thick. The surface layer is and landings when the soil is dry can improve the growth of very dark brown gravelly loam about 5 inches thick. The plants. next layer is very dark grayish brown gravelly loam about 7 Properly designed road drainage systems that include inches thick. The upper 10 inches of the subsoil is dark carefully located culverts help to control erosion. Areas that grayish brown very gravelly loam. The lower 17 inches is have been cut and filled are easily eroded unless they are olive very cobbly loam. Bedrock is at a depth of about 39 treated. Seeding, mulching, and benching these areas help inches. The depth to bedrock ranges from 20 to 40 inches. to control erosion. Steep yarding paths, skid trails, and In some areas the surface layer is very gravelly or stony. firebreaks are subject to rilling and gullying unless they are Included in this unit are small areas of Acker and protected by a plant cover or adequate water bars, or both. Norling soils and soils that are similar to the Snowbrier soil Cutbanks occasionally slump when the soil is saturated. but have less than 35 percent rock fragments or have Constructing logging roads on the steeper slopes can bedrock at a depth of more than 40 inches. Also included result in a high risk of erosion. Material that is discarded are small areas of Snowbrier soils that have slopes of less when the roads are built can damage vegetation and is a than 25 or more than 50 percent. Included areas make up potential source of sedimentation. If the material becomes about 20 percent of the total acreage. saturated, avalanches of debris can occur. End hauling of Permeability is moderate in the Snowbrier soil. Available the waste material minimizes damage to the vegetation water capacity is about 4 inches. The effective rooting depth downslope and reduces the risk of sedimentation. Skid trails is 20 to 40 inches. Runoff is medium or rapid, and the and unsurfaced roads may be impassable during rainy hazard of water erosion is high. periods. Logging roads require suitable surfacing for This unit is used for timber production and wildlife year-round use. habitat. It is suited to the production of Douglas fir and Undesirable plants limit natural or artificial reforestation white fir. Other species that grow on this unit include unless intensive site preparation and maintenance incense cedar, golden chinkapin, and western hemlock. measures are applied. Reforestation can be accomplished The understory vegetation includes Pacific rhododendron, by planting Douglas fir seedlings. Mulching around cascade Oregongrape, and deerfoot vanillaleaf. seedlings helps to maintain the moisture supply in On the basis of a 100-year site curve, the mean site summer and minimizes competition from undesirable index for Douglas fir is 140. The yield at culmination of the plants. mean annual increment is 8,700 cubic feet per acre in a Severe frost can damage or kill seedlings. A high fully stocked, even-aged stand of trees at 60 years and temperature in the surface layer during summer and the low 69,410 board feet per acre (Scribner rule) at 110 years. On available water capacity increase the seedling mortality rate. the basis of a 50-year curve, the mean site index is 105. The large number of rock fragments in the soil also The main limitations affecting timber production are the increases the seedling mortality rate. To compensate for the slope, erosion, compaction, plant competition, and expected high mortality rate, the larger seedlings or a seedling mortality. Also, the bedrock restricts root growth. greater number of seedlings should be planted. When the As a result, windthrow is a hazard. timber is harvested, leaving some of the larger trees When timber is harvested, management that minimizes unharvested provides shade for seedlings. the risk of erosion is essential. Wheeled and tracked Increased erosion, loss of plant nutrients, and water logging equipment can be used in the less sloping areas, repellency are likely to result from fires of moderate but cable yarding generally is safer and results in less intensity. surface disturbance. If the soil is The vegetative site is Mixed Fir-Salal (rhododendron) Forest. 176F-Snowbrier gravelly loam, 25 to 50 percent logging roads are built, a larger number of rock fragments is south slopes. This moderately deep, well drained soil is on left on the surface. Using standard wheeled and tracked hillslopes. It formed in colluvium derived dominantly from equipment when the soil is moist causes rutting and schist. Elevation is 3,600 to 4,700 feet. The mean annual compaction. Puddling can occur when the soil is wet. Using precipitation is 40 to 60 inches, the mean annual low-pressure ground equipment causes less damage to the temperature is 40 to 45 degrees F, and the average soil and helps to maintain productivity. Compaction can be frost-free period is less than 100 days. The native minimized by using suitable methods of harvesting, laying vegetation is mainly conifers and an understory of grasses, out skid trails in advance, and harvesting timber when the shrubs, and forbs. soil is least susceptible to compaction. Ripping skid trails Typically, the surface is covered with a layer of needles, and landings when the soil is dry can improve the growth of leaves, and twigs about 1 inch thick. The surface layer is plants. very dark brown gravelly loam about 5 inches thick. The Properly designed road drainage systems that include next layer is very dark grayish brown gravelly loam about 7 carefully located culverts help to control erosion. Areas that inches thick. The upper 10 inches of the subsoil is dark have been cut and filled are easily eroded unless they are grayish brown very gravelly loam. The lower 17 inches is treated. Seeding, mulching, and benching these areas help olive very cobbly loam. Bedrock is at a depth of about 39 to control erosion. Steep yarding paths, skid trails, and inches. The depth to bedrock ranges from 20 to 40 inches. firebreaks are subject to rilling and gullying unless they are In some areas the surface layer is very gravelly or stony. protected by a plant cover or adequate water bars, or both. Included in this unit are small areas of Acker and Cutbanks occasionally slump when the soil is saturated. Norling soils and soils that are similar to the Snowbrier soil Constructing logging roads on the steeper slopes can but have less than 35 percent rock fragments or have result in a high risk of erosion. Material that is discarded bedrock at a depth of more than 40 inches. Also included when the roads are built can damage vegetation and is a are small areas of Snowbrier soils that have slopes of less potential source of sedimentation. If the material becomes than 25 or more than 50 percent. Included areas make up saturated, avalanches of debris can occur. End hauling of about 20 percent of the total acreage. the waste material minimizes damage to the vegetation Permeability is moderate in the Snowbrier soil. Available downslope and reduces the risk of sedimentation. Skid trails water capacity is about 4 inches. The effective rooting depth and unsurfaced roads may be impassable during rainy is 20 to 40 inches. Runoff is medium or rapid, and the periods. Logging roads require suitable surfacing for hazard of water erosion is high. year-round use. This unit is used for timber production and wildlife Severe frost can damage or kill seedlings. A high habitat. It is suited to the production of Douglas fir and temperature in the surface layer during summer and the low white fir. Other species that grow on this unit include available water capacity increase the seedling mortality rate. incense cedar, sugar pine, and Pacific madrone. The The large number of rock fragments in the soil also understory vegetation includes golden chinkapin, cascade increases the seedling mortality rate. To compensate for the Oregongrape, and Whipplevine. expected high mortality rate, the larger seedlings or a On the basis of a 100-year site curve, the mean site greater number of seedlings should be planted. When the index for Douglas fir is 130. The yield at culmination of the timber is harvested, leaving some of the larger trees mean annual increment is 7,740 cubic feet per acre in a unharvested provides shade for seedlings. The seedling fully stocked, even-aged stand of trees at 60 years and mortality rate also can be reduced by providing artificial 58,520 board feet per acre (Scribner rule) at 110 years. On shade for seedlings. Reforestation can be accomplished by the basis of a 50-year curve, the mean site index is 95. planting Douglas fir seedlings. The main limitations affecting timber production are the Undesirable plants limit natural or artificial slope, erosion, compaction, seedling mortality, and plant reforestation unless intensive site preparation and competition. Also, the bedrock restricts root growth. As a maintenance measures are applied. Mulching around result, windthrow is a hazard. seedlings helps to maintain the moisture supply in When timber is harvested, management that minimizes summer and minimizes competition from undesirable the risk of erosion is essential. Wheeled and tracked plants. logging equipment can be used in the less sloping areas, Increased erosion, loss of plant nutrients, and water but cable yarding generally is safer and results in less repellency are likely to result from fires of moderate surface disturbance. If the soil is excessively disturbed intensity. when timber is harvested or The vegetative site is Douglas Fir-Madrone- least susceptible to compaction. Ripping skid trails and Chinkapin Forest. landings when the soil is dry can improve the growth of plants. 177C-Snowlin gravelly loam, 3 to 12 percent slopes. Erosion can be controlled by carefully planning the This very deep, well drained soil is on plateaus. It formed in construction and maintenance of logging roads, skid trails, colluvium derived from andesite and volcanic ash. Elevation and landings. Seeding, mulching, and benching areas that is 4,000 to 6,000 feet. The mean annual precipitation is 40 have been cut and filled also help to control erosion. Skid to 50 inches, the mean annual temperature is 40 to 45 trails and unsurfaced roads may be impassable during degrees F, and the average frost-free period is less than rainy periods. Logging roads require suitable surfacing for 100 days. The native vegetation is mainly conifers and an year-round use. understory of grasses, shrubs, and forbs. Severe frost can damage or kill seedlings. Air Typically, the surface is covered with a layer of needles drainage is restricted on this unit. Proper timber and twigs about 2 inches thick. The surface layer is dark harvesting methods can reduce the effect of frost on reddish brown gravelly loam about 20 inches thick. The regeneration. Reforestation can be accomplished by upper 14 inches of the subsoil is dark reddish brown planting seedlings of frost-tolerant species, such as gravelly clay loam. The lower 26 inches is dark reddish ponderosa pine and lodgepole pine. brown very gravelly clay loam. The depth to bedrock is 60 Undesirable plants limit natural or artificial inches or more. In some areas the surface layer is stony. reforestation unless intensive site preparation and Included in this unit are small areas of poorly drained maintenance measures are applied. Mulching around soils near drainageways and on concave slopes, seedlings helps to maintain the moisture supply in Rustlerpeak soils on convex slopes and on the more sloping summer and minimizes competition from undesirable parts of the landscape, and soils that are similar to the plants. Snowlin soil but have bedrock within a depth of 60 inches. The main limitation affecting livestock grazing is Also included are small areas of Snowlin soils that have compaction. The native vegetation suitable for grazing slopes of less than 3 or more than 12 percent. Included includes Canada bluegrass, Alaska oniongrass; and areas make up about 15 percent of the total acreage. mountain brome. If the understory is overgrazed, the Permeability is moderately slow in the Snowlin soil. proportion of preferred forage plants decreases and the Available water capacity is about 8 inches. The effective proportion of less preferred forage plants increases. rooting depth is 60 inches or more. Runoff is slow, and. the A planned grazing system that includes timely deferment hazard of water erosion is slight. of grazing, rotation grazing, and proper livestock distribution This unit is used for timber production, livestock helps to prevent overgrazing of the understory and damage grazing, and wildlife habitat. to the soil. Grazing should be delayed until the more This unit is suited to the production of white fir. Other desirable forage plants have achieved enough growth to species that grow on this unit include Douglas fir, incense withstand grazing pressure and the soil is firm enough to cedar, and Rocky Mountain maple. The understory withstand trampling by livestock. vegetation includes cascade Oregongrape, western white Thinning, logging, and fire reduce the density of the anemone, and gooseberry. overstory canopy and increase the production of On the basis of a 50-year site curve, the mean site understory vegetation. Areas that support a large amount index for white fir is 80. The yield at culmination of the of competing vegetation can be improved by prescribed mean annual increment is 13,720 cubic feet per acre in a burning or by chemical or mechanical treatment. Seeding fully stocked, even-aged stand of trees at 70 years. disturbed areas to suitable plants increases forage The main limitations affecting timber production are production and reduces the risk of erosion. The seedling compaction, erosion, seedling mortality, and plant survival rate may be limited, however, because of cold competition. Conventional methods of harvesting timber temperatures in spring. generally are suitable, but the soil may be compacted if it is The vegetative site is White Fir Forest. moist when heavy equipment is used. Puddling can occur when the soil is wet. Using low-pressure ground equipment 178E-Snowlin gravelly loam, 12 to 35 percent north causes less damage to the soil and helps to maintain slopes. This very deep, well drained soil is on hillslopes. It productivity. Compaction can be minimized by using formed in colluvium derived from andesite and volcanic suitable methods of harvesting, laying out skid trails in ash. Elevation is 4,000 to 6,000 feet. The mean annual advance, and harvesting timber when the soil is precipitation is 40 to 50 inches, the mean annual temperature is 40 to 45 degrees F, and the average frost-free period is less than 100 days. The native vegetation is mainly conifers and an understory of paths, skid trails, and firebreaks are subject to rilling and grasses, shrubs, and forbs. gullying unless they are protected by a plant cover or Typically, the surface is covered with a layer of needles adequate water bars, or both. Skid trails and unsurfaced and twigs about 2 inches thick. The surface layer is dark roads may be impassable during rainy periods. Logging reddish brown gravelly loam about 20 inches thick. The roads require suitable surfacing for year-round use. upper 14 inches of the subsoil is dark reddish brown Undesirable plants limit natural or artificial reforestation gravelly clay loam. The lower 26 inches is dark reddish unless intensive site preparation and maintenance brown very gravelly clay loam. The depth to bedrock is 60 measures are applied. Reforestation can be accomplished inches or more. In some areas the surface layer is stony. by planting ponderosa pine and Douglas fir seedlings. Included in this unit are small areas of poorly drained Mulching around seedlings helps to maintain the moisture soils near drainageways and on concave slopes, supply in summer and minimizes competition from Rustlerpeak soils on convex slopes and on the more sloping undesirable plants. parts of the landscape, and soils that are similar to the Severe frost can damage or kill seedlings. In the less Snowlin soil but have bedrock within a depth of 60 inches. sloping areas where air drainage may be restricted, proper Also included are small areas of Snowlin soils that have timber harvesting methods can reduce the effect of frost on slopes of less than 12 or more than 35 percent. Included regeneration. areas makeup about 15 percent of the total acreage. The main limitations affecting livestock grazing are Permeability is moderately slow in the Snowlin soil. compaction and erosion. The native vegetation suitable for Available water capacity is about 8 inches. The effective grazing includes Canada bluegrass, Alaska oniongrass, rooting depth is 60 inches or more. Runoff is medium, and and mountain brome. If the understory is overgrazed, the the hazard of water erosion is moderate. proportion of preferred forage plants decreases and the This unit is used for timber production, livestock proportion of less preferred forage plants increases. grazing, and wildlife habitat. A planned grazing system that includes timely deferment This unit is suited to the production of white fir. Other of grazing, rotation grazing, and proper livestock distribution species that grow on this unit include Douglas fir, incense helps to prevent overgrazing of the understory and damage cedar, and Rocky Mountain maple. The understory to the soil. Grazing should be delayed until the more vegetation includes cascade Oregongrape, western white desirable forage plants have achieved enough growth to anemone, and gooseberry. withstand grazing pressure and the soil is firm enough to On the basis of a 50-year site curve, the mean site withstand trampling by livestock. index for white fir is 80. The yield at culmination of the Thinning, logging, and fire reduce the density of the mean annual increment is 13,720 cubic feet per acre in a overstory canopy and increase the production of fully stocked, even-aged stand of trees at 70 years. understory vegetation. Areas that support a large amount The main limitations affecting timber production are of competing vegetation can be improved by prescribed erosion, compaction, plant competition, and seedling burning or by chemical or mechanical treatment. Seeding mortality. Wheeled and tracked logging equipment can be disturbed areas to suitable plants increases forage used in the less sloping areas, but cable yarding generally production and reduces the risk of erosion. The seedling is safer in the more sloping areas and results in less survival rate may be limited, however, because of cold surface disturbance. Using standard wheeled and tracked temperatures in spring. equipment when the soil is moist causes rutting and The vegetative site is White Fir Forest. compaction. Puddling can occur when the soil is wet. Using low-pressure ground equipment causes less damage to the 179F-Speaker-Josephine complex, 35 to 55 soil and helps to maintain productivity. Compaction can be percent south slopes. This map unit is on hillslopes. minimized by using suitable methods of harvesting, laying Elevation is 1,200 to 4,000 feet. The mean annual out skid trails in advance, and harvesting timber when the precipitation is 40 to 50 inches, the mean annual soil is least susceptible to compaction. Ripping skid trails temperature is 45 to 52 degrees F, and the average and landings when the soil is dry can improve the growth of frost-free period is 100 to 160 days. The native plants. vegetation is mainly conifers and hardwoods and an Properly designed road drainage systems that include understory of grasses, shrubs, and forbs. carefully located culverts help to control erosion. Seeding, This unit is about 45 percent Speaker soil and 40 mulching, and benching areas that have been cut and filled percent Josephine soil. The components of this unit occur also help to control erosion. Steep yarding as areas so intricately intermingled that mapping them separately was not practical at the scale used. acre (Scribner rule) at 130 years. On the basis of a 50-year Included in this unit are small areas of Dubakella, curve, the mean site index is 85. Goolaway, Pearsoll, and Siskiyou soils; Pollard, Beekman, On the basis of a 100-year site curve, the mean site and McMullin soils on the less sloping parts of the index for ponderosa pine is 105 on the Speaker soil. The landscape and on concave slopes; poorly drained soils near yield at culmination of the mean annual increment is 4,480 drainageways and on concave slopes; and soils that are cubic feet per acre in a fully stocked, even-aged stand of similar to the Speaker and Josephine soils but have more trees at 40 years and 50,040 board feet per acre (Scribner than 35 percent rock fragments. Also included are small rule) at 120 years. areas of Speaker and Josephine soils that have slopes of On the basis of a 100-year site curve, the mean site less than 35 or more than 55 percent. Included areas make index for Douglas fir is 120 on the Josephine soil. The yield up about 15 percent of the total acreage. at culmination of the mean annual increment is 6,900 cubic The Speaker soil is moderately deep and well drained. It feet per acre in a fully stocked, even-aged stand of trees at formed in colluvium derived dominantly from metamorphic 60 years and 52,440 board feet per acre (Scribner rule) at rock. Typically, the surface is covered with a layer of 120 years. On the basis of a 50-year curve, the mean site needles, leaves, and twigs about 1 inch thick. The surface index is 90. layer is dark brown loam about 13 inches thick. The upper On the basis of a 100-year site curve, the mean site 10 inches of the subsoil also is dark brown loam. The lower index for ponderosa pine is 115 on the Josephine soil. The 12 inches is brown gravelly clay loam. Weathered bedrock yield at culmination of the mean annual increment is 5,280 is at a depth of about 35 inches. The depth to bedrock cubic feet per acre in a fully stocked, even-aged stand of ranges from 20 to 40 inches. In some areas the surface trees at 40 years and 56,780 board feet per acre (Scribner layer is gravelly loam. rule) at 110 years. Permeability is moderately slow in the Speaker soil. The main limitations affecting timber production are the Available water capacity is about 4 inches. The effective slope, erosion, compaction, seedling mortality, and plant rooting depth is 20 to 40 inches. Runoff is rapid, and the competition. Wheeled and tracked logging equipment can hazard of water erosion is high. be used in the less sloping areas, but cable yarding The Josephine soil is deep and well drained. It formed in generally is safer and results in less surface disturbance. colluvium and residuum derived dominantly from Using standard wheeled and tracked equipment when the metamorphic rock. Typically, the surface is covered with a soils are moist causes rutting and compaction. Puddling can layer of needles, leaves, and twigs about 1 inch thick. The occur when the soils are wet. Using low-pressure ground surface layer is dark reddish brown gravelly loam about 15 equipment causes less damage to the soils and helps to inches thick. The subsoil is dark reddish brown and reddish maintain productivity. Compaction can be minimized by brown gravelly clay loam about 40 inches thick. Weathered using suitable methods of harvesting, laying out skid trails in bedrock is at a depth of about 55 inches. The depth to advance, and harvesting timber when the soils are least bedrock ranges from 40 to 60 inches. In some areas the susceptible to compaction. Ripping skid trails and landings surface layer is clay loam. when the soils are dry can improve the growth of plants. Permeability is moderately slow in the Josephine soil. Properly designed road drainage systems that include Available water capacity is about 7 inches. The effective carefully located culverts help to control erosion. Seeding, rooting depth is 40 to 60 inches. Runoff is rapid, and the mulching, and benching areas that have been cut and filled hazard of water erosion is high. also help to control erosion. Steep yarding paths, skid trails, This unit is used for timber production and wildlife and firebreaks are subject to rilling and gullying unless they habitat. It is suited to the production of Douglas fir and are protected by a plant cover or adequate water bars, or ponderosa pine. Other species that grow on this unit both. Cutbanks occasionally slump when the soils are include sugar pine and California black oak. The saturated. understory vegetation includes canyon live oak, Constructing logging roads on the steeper slopes can deerbrush, and western fescue. result in a high risk of erosion. Material that is discarded On the basis of a 100-year site curve, the mean site when the roads are built can damage vegetation and is a index for Douglas fir is 115 on the Speaker soil. The yield potential source of sedimentation. If the material becomes at culmination of the mean annual increment is 6,360 cubic saturated, avalanches of debris can occur. End hauling of feet per acre in a fully stocked, even-aged stand of trees at the waste material minimizes damage to the vegetation 60 years and 50,700 board feet per downslope and reduces the risk of sedimentation. Skid trails and unsurfaced roads may be impassable during rainy periods. Logging roads require understory vegetation includes golden chinkapin, salal, suitable surfacing for year-round use. and cascade Oregongrape. A high temperature in the surface layer and an On the basis of a 100-year site curve, the mean site insufficient moisture supply in summer increase the seedling index for Douglas fir is 140. The yield at culmination of the mortality rate. To compensate for the expected high mean annual increment is 8,700 cubic feet per acre in a mortality rate, the larger seedlings or a greater number of fully stocked, even-aged stand of trees at 60 years and seedlings should be planted. When the timber is harvested, 69,410 board feet per acre (Scribner rule) at 110 years. On leaving some of the larger trees unharvested provides the basis of a 50-year curve, the mean site index is 110. shade for seedlings. The seedling mortality rate also can be The main limitations affecting timber production are the reduced by providing artificial shade for seedlings. slope, erosion, compaction, plant competition, and seedling Reforestation can be accomplished by planting Douglas fir mortality. When timber is harvested, management that and ponderosa pine seedlings. minimizes the risk of erosion is essential. Wheeled and Undesirable plants limit natural or artificial tracked logging equipment can be used in the less sloping reforestation unless intensive site preparation and areas, but cable yarding generally is safer and results in maintenance measures are applied. Mulching around less surface disturbance. Using standard wheeled and seedlings helps to maintain the moisture supply in tracked equipment when the soil is moist causes rutting summer and minimizes competition from undesirable and compaction. Puddling can occur when the soil is wet. plants. Using low-pressure ground equipment causes less damage The vegetative site is Douglas Fir-Black Oak Forest. to the soil and helps to maintain productivity. Compaction can be minimized by using suitable methods of harvesting, 180G-Steinmetz sandy loam, 35 to 75 percent north laying out skid trails in advance, and harvesting timber slopes. This very deep, somewhat excessively drained soil when the soil is least susceptible to compaction. Ripping is on hillslopes. It formed in colluvium derived from granitic skid trails and landings when the soil is dry can improve the rock. Elevation is 2,000 to 4,000 feet. The mean annual growth of plants. precipitation is 45 to 60 inches, the mean annual Properly designed road drainage systems that include temperature is 45 to 50 degrees F, and the average carefully located culverts help to control erosion. Areas that frost-free period is 100 to 160 days. The native vegetation have been cut and filled are easily eroded unless they are is mainly conifers and hardwoods and an understory of treated. Seeding, mulching, and benching these areas help grasses, shrubs, and forbs. to control erosion. Steep yarding paths, skid trails, and Typically, the surface is covered with a layer of needles firebreaks are subject to rilling and gullying unless they are and twigs about 1 inch thick. The surface layer is very dark protected by a plant cover or adequate water bars, or both. grayish brown and brown sandy loam about 13 inches thick. Cutbanks occasionally slump when the soil is saturated. The subsoil to a depth of 60 inches is dark yellowish brown This unit is subject to slumping, especially in areas and brown sandy loam. The depth to bedrock is 60 inches adjacent to drainageways. Road failure and landslides are or more. likely to occur after road construction and clearcutting. Included in this unit are small areas of Dubakella, Constructing logging roads on the steeper slopes can Goolaway, Gravecreek, Musty, and Rogue soils; Rock result in a high risk of erosion. Building the roads at outcrop; Atring and Kanid soils on the more sloping parts of midslope requires extensive cutting and filling and removes the landscape; Lettia soils on the less sloping parts of the land from production. Material that is discarded when the landscape and on concave slopes; and soils that are roads are built can damage vegetation and is a potential similar to the Steinmetz soil but that have bedrock within a source of sedimentation. If the material becomes saturated, depth of 60 inches. Also included are small areas of avalanches of debris can occur. End hauling of the waste Steinmetz soils that have slopes of less than 35 or more material minimizes damage to the vegetation downslope than 75 percent. Included areas make up about 20 percent and reduces the risk of sedimentation. Skid trails and of the total acreage. unsurfaced roads may be impassable during rainy periods. Permeability is moderately rapid in the Steinmetz soil. Logging roads require suitable surfacing for year-round use. Available water capacity is about 6 inches. The effective Undesirable plants limit natural or artificial reforestation rooting depth is 60 inches or more. Runoff is rapid, and unless intensive site preparation and maintenance the hazard of water erosion is high. measures are applied. Reforestation can This unit is used for timber production and wildlife habitat. It is suited to the production of Douglas fir. Other species that grow on this unit include incense cedar, western hemlock, and Pacific madrone. The be accomplished by planting Douglas fir seedlings. the mean annual increment is 7,740 cubic feet per acre in a Mulching around seedlings helps to maintain the moisture fully stocked, even-aged stand of trees at 60 years and supply in summer and minimizes competition from 58,520 board feet per acre (Scribner rule) at 110 years. On undesirable plants. the basis of a 50-year curve, the mean site index is 100. A high temperature in the surface layer and an The main limitations affecting timber production are the insufficient moisture supply in summer increase the slope, erosion, compaction, seedling mortality, and plant seedling mortality rate. To compensate for the expected competition. When timber is harvested, management that high mortality rate, the larger seedlings or a greater number minimizes the risk of erosion is essential. Wheeled and of seedlings should be planted. When the timber is tracked logging equipment can be used in the less sloping harvested, leaving some of the larger trees unharvested areas, but cable yarding generally is safer and results in provides shade for seedlings. less surface disturbance. Using standard wheeled and Increased erosion, loss of plant nutrients, and water tracked equipment when the soil is moist causes rutting and repellency are likely to result from fires of moderate compaction. Puddling can occur when the soil is wet. Using intensity. low-pressure ground equipment causes less damage to the The vegetative site is Mixed Fir-Salal (rhododendron) soil and helps to maintain productivity. Compaction can be Forest. minimized by using suitable methods of harvesting, laying out skid trails in advance, and harvesting timber when the 181G-Steinmetz sandy loam, 35 to 75 percent south soil is least susceptible to compaction. Ripping skid trails slopes. This very deep, somewhat excessively drained soil and landings when the soil is dry can improve the growth of is on hillslopes. It formed in colluvium derived from granitic plants. rock. Elevation is 2,000 to 4,000 feet. The mean annual Properly designed road drainage systems that include precipitation is 45 to 60 inches, the mean annual carefully located culverts help to control erosion. Areas that temperature is 45 to 50 degrees F, and the average have been cut and filled are easily eroded unless they are frost-free period is 100 to 160 days. The native vegetation treated. Seeding, mulching, and benching these areas help is mainly conifers and hardwoods and an understory of to control erosion. Steep yarding paths, skid trails, and grasses, shrubs, and forbs. firebreaks are subject to rilling and gullying unless they are Typically, the surface is covered with a layer of needles protected by a plant cover or adequate water bars, or both. and twigs about 1 inch thick. The surface layer is very dark Cutbanks occasionally slump when the soil is saturated. grayish brown and brown sandy loam about 13 inches thick. This unit is subject to slumping, especially in areas The subsoil to a depth of 60 inches is dark yellowish brown adjacent to drainageways. Road failure and landslides are and brown sandy loam. The depth to bedrock is 60 inches likely to occur after road construction and clearcutting. or more. Constructing logging roads on the steeper slopes can Included in this unit are small areas of Dubakella, result in a high risk of erosion. Building the roads at Goolaway, Gravecreek, Musty, and Rogue soils; Rock midslope requires extensive cutting and filling and removes outcrop; Atring and Kanid soils on the more sloping parts land from production. Material that is discarded when the of the landscape; Lettia soils on the less sloping parts of roads are built can damage vegetation and is a potential the landscape and on concave slopes; and soils that are source of sedimentation. If the material becomes saturated, similar to the Steinmetz soil but have bedrock within a avalanches of debris can occur. End hauling of the waste depth of 60 inches. Also included are small areas of material minimizes damage to the vegetation downslope Steinmetz soils that have slopes of less than 35 or more and reduces the risk of sedimentation. Skid trails and than 75 percent. Included areas make up about 20 percent unsurfaced roads may be impassable during rainy periods. of the total acreage. Logging roads require suitable surfacing for year-round use. Permeability is moderately rapid in the Steinmetz soil. A high temperature in the surface layer and an Available water capacity is about 6 inches. The effective insufficient moisture supply in summer increase the seedling rooting depth is 60 inches or more. Runoff is rapid, and mortality rate. To compensate for the expected high the hazard of water erosion is high. mortality rate, the larger seedlings or a greater number of This unit is used for timber production and wildlife seedlings should be planted. When the timber is harvested, habitat. It is suited to the production of Douglas fir. Other leaving some of the larger trees unharvested provides species that grow on this unit include incense cedar, sugar shade for seedlings. The seedling pine, and Pacific madrone. The understory vegetation includes golden chinkapin, Whipplevine, and cascade Oregongrape. On the basis of a 100-year site curve, the mean site index for Douglas fir is 130. The yield at culmination of mortality rate also can be reduced by providing artificial vegetation includes Pacific serviceberry, cascade shade for seedlings. Reforestation can be accomplished by Oregongrape, and deerfoot vanillaleaf. planting Douglas fir and ponderosa pine seedlings. On the basis of a 100 year site curve, the mean site Undesirable plants limit natural or artificial index for Douglas fir is 115. The yield at culmination of the reforestation unless intensive site preparation and mean annual increment is 6,360 cubic feet per acre in a maintenance measures are applied. Mulching around fully stocked, even-aged stand of trees at 60 years and seedlings helps to maintain the moisture supply in 50,700 board feet per acre (Scribner rule) at 130 years. On summer and minimizes competition from undesirable the basis of a 50-year curve, the mean site index is 85. plants. The main limitations affecting timber production are Increased erosion, loss of plant nutrients, and water erosion, compaction, plant competition, and seedling repellency are likely to result from fires of moderate mortality. Also, the bedrock restricts root growth. As a intensity. result, windthrow is a hazard. The vegetative site is Douglas Fir-Madrone- Wheeled and tracked logging equipment can be used in Chinkapin Forest. the less sloping areas, but cable yarding generally is safer in the more sloping areas and results in less surface 182E-Straight extremely gravelly loam, 12 to 35 disturbance. If the soil is excessively disturbed when timber percent north slopes. This moderately deep, well drained is harvested or logging roads are built, a larger number of soil is on hillslopes. It formed in colluvium derived from rock fragments is left on the surface. Using standard andesite, tuff, and breccia. Elevation is 2,000 to 4,000 feet. wheeled and tracked equipment when the soil is moist The mean annual precipitation is 35 to 55 inches, the mean causes rutting and compaction. Puddling can occur when annual temperature is 45 to 52 degrees F, and the average the soil is wet. Using low-pressure ground equipment frost-free period is 100 to 160 days. The native vegetation is causes less damage to the soil and helps to maintain mainly conifers and hardwoods and an understory of productivity. Compaction can be minimized by using grasses, shrubs, and forbs. suitable methods of harvesting, laying out skid trails in Typically, the surface is covered with a layer of needles, advance, and harvesting timber when the soil is least leaves, and twigs about 1'/2 inches thick. The surface layer susceptible to compaction. Ripping skid trails and landings is dark reddish brown extremely gravelly loam about 9 when the soil is dry can improve the growth of plants. inches thick. The next layer is dark brown very gravelly loam Properly designed road drainage systems that include about 10 inches thick. The upper 11 inches of the subsoil carefully located culverts help to control erosion. Areas that also is dark brown very gravelly loam. The lower 5 inches is have been cut and filled are easily eroded unless they are dark brown very cobbly clay Ioam. Weathered bedrock is at treated. Seeding, mulching, and benching these areas help a depth of about 35 inches. The depth to bedrock ranges to control erosion. Steep yarding paths, skid trails, and from 20 to 40 inches. In some areas the surface layer is firebreaks are subject to rilling and gullying unless they are gravelly or stony. protected by a plant cover or adequate water bars, or both. Included in this unit are small areas of Freezener and Skid trails and unsurfaced roads may be impassable during Geppert soils, Rock outcrop and Shippa soils on ridges and rainy periods. Logging roads require suitable surfacing for convex slopes, poorly drained soils near drainageways and year-round use. on concave slopes, and soils that are similar to the Straight Undesirable plants limit natural or artificial reforestation soil but have bedrock at a depth of more than 40 inches. unless intensive site preparation and maintenance Also included are small areas of Straight soils that have measures are applied. Reforestation can be accomplished slopes of less than 12 or more than 35 percent. Included by planting Douglas fir and ponderosa pine seedlings. areas make up about 20 percent of the total acreage. Mulching around seedlings helps to maintain the moisture Permeability is moderate in the Straight soil. Available supply in summer and minimizes competition from water capacity is about 3 inches. The effective rooting depth undesirable plants. is 20 to 40 inches. Runoff is medium, and the hazard of A high temperature in the surface layer during summer water erosion is moderate. and the low available water capacity increase the seedling This unit is used for timber production, livestock mortality rate. The large number of rock fragments in the grazing, and wildlife habitat. soil also increases the seedling mortality rate. To This unit is suited to the production of Douglas fir. compensate for the expected high mortality rate, the larger Other species that grow on this unit include white fir, seedlings or a greater number of seedlings should be incense cedar, and Pacific dogwood. The understory planted. When the timber is harvested, leaving some of the larger trees unharvested of Straight soils that have slopes of less than 12 or more provides shade for seedlings. than 35 percent. Included areas make up about 20 The main limitations affecting livestock grazing are percent of the total acreage. compaction and erosion. The native vegetation suitable for Permeability is moderate in the Straight soil. Available grazing includes western fescue, mountain brome, tall water capacity is about 3 inches. The effective rooting depth trisetum, and Alaska oniongrass. If the understory is is 20 to 40 inches. Runoff is medium, and the hazard of overgrazed, the proportion of preferred forage plants water erosion is moderate. decreases and the proportion of less preferred forage This unit is used for timber production, livestock plants increases. grazing, and wildlife habitat. A planned grazing system that includes timely This unit is suited to the production of Douglas fir. Other deferment of grazing, rotation grazing, and proper livestock species that grow on this unit include sugar pine, distribution helps to prevent overgrazing of the understory ponderosa pine, white fir, and California black oak. The and damage to the soil. Grazing should be delayed until understory vegetation includes Pacific serviceberry, tall the more desirable forage plants have achieved enough Oregongrape, and western fescue. growth to withstand grazing pressure and the soil is firm On the basis of a 100-year site curve, the mean site enough to withstand trampling by livestock. index for Douglas fir is 110. The yield at culmination of the Thinning, logging, and fire reduce the density of the mean annual increment is 5,880 cubic feet per acre in a overstory canopy and increase the production of fully stocked, even-aged stand of trees at 60 years and understory vegetation. Areas that support a large amount 48,300 board feet per acre (Scribner rule) at 140 years. On of competing vegetation can be improved by prescribed the basis of a 50-year curve, the mean site index is 75. burning or by chemical or mechanical treatment. Seeding The main limitations affecting timber production are disturbed areas to suitable plants increases forage erosion, compaction, seedling mortality, and plant production and reduces the risk of erosion. competition. Also, the bedrock restricts root growth. As a The vegetative site is Mixed Fir-Dogwood Forest. result, windthrow is a hazard. Wheeled and tracked logging equipment can be used in 183E-Straight extremely gravelly loam, 12 to 35 the less sloping areas, but cable yarding generally is safer in percent south slopes. This moderately deep, well drained the more sloping areas and results in less surface soil is on hillslopes. It formed in colluvium derived from disturbance. If the soil is excessively disturbed when timber andesite, tuff, and breccia. Elevation is 2,000 to 4,000 feet. is harvested or logging roads are built, a larger number of The mean annual precipitation is 35 to 55 inches, the mean rock fragments is left on the surface. Using standard annual temperature is 45 to 52 degrees F, and the average wheeled and tracked equipment when the soil is moist frost-free period is 100 to 160 days. The native vegetation causes rutting and compaction. Puddling can occur when is mainly conifers and hardwoods and an understory of the soil is wet. Using low-pressure ground equipment grasses, shrubs, and forbs. causes less damage to the soil and helps to maintain Typically, the surface is covered with a layer of needles, productivity. Compaction can be minimized by using suitable leaves, and twigs about 1 1/2 inches thick. The surface methods of harvesting, laying out skid trails in advance, and layer is dark reddish brown extremely gravelly loam about 9 harvesting timber when the soil is least susceptible to inches thick. The next layer is dark brown very gravelly compaction. Ripping skid trails and landings when the soil is loam about 10 inches thick. The upper 11 inches of the dry can improve the growth of plants. subsoil also is dark brown very gravelly loam. The lower 5 Properly designed road drainage systems that include inches is dark brown very cobbly clay loam. Weathered carefully located culverts help to control erosion. Areas that bedrock is at a depth of about 35 inches. The depth to have been cut and filled are easily eroded unless they are bedrock ranges from 20 to 40 inches. In some areas the treated. Seeding, mulching, and benching these areas help surface layer is gravelly or stony. to control erosion. Steep yarding paths, skid trails, and Included in this unit are small areas of Freezener and firebreaks are subject to rilling and gullying unless they are Geppert soils, Rock outcrop and Shippa soils on ridges and protected by a plant cover or adequate water bars, or both. convex slopes, poorly drained soils near drainageways and Skid trails and unsurfaced roads may be impassable during on concave slopes, and soils that are similar to the Straight rainy periods. Logging roads require suitable surfacing for soil but have bedrock at a depth of more than 40 inches. year-round use. Also included are small areas A high temperature in the surface layer during summer and the low available water capacity increase the seedling mortality rate. The large number of rock slopes, soils that are similar to the Straight soil but have fragments in the soil also increases the seedling mortality bedrock at a depth of more than 40 inches, and soils that rate. To compensate for the expected high mortality rate, the are similar to the Shippa soil but have bedrock within a larger seedlings or a greater number of seedlings should be depth of 10 inches. Also included are small areas of Straight planted. When the timber is harvested, leaving some of the and Shippa soils that have slopes of less than 35 or more larger trees unharvested provides shade for seedlings. than 70 percent. Included areas make up about 20 percent Reforestation can be accomplished by planting Douglas fir of the total acreage. and ponderosa pine seedlings. The Straight soil is moderately deep and well drained. It Undesirable plants limit natural or artificial reforestation formed in colluvium derived dominantly from andesite, tuff, unless intensive site preparation and maintenance and breccia. Typically, the surface is covered with a layer of measures are applied. Mulching around seedlings helps to needles, leaves, and twigs about 11/2 inches thick. The maintain the moisture supply in summer and minimizes surface layer is dark reddish brown extremely gravelly loam competition from undesirable plants. about 9 inches thick. The next layer is dark brown very The main limitations affecting livestock grazing are gravelly loam about 10 inches thick. The upper 11 inches of compaction and erosion. The native vegetation suitable for the subsoil also is dark brown very gravelly loam. The lower grazing includes western fescue, mountain brome, tall 5 inches is dark brown very cobbly clay loam. Weathered trisetum, and Alaska oniongrass. If the understory is bedrock is at a depth of about 35 inches. The depth to overgrazed, the proportion of preferred forage plants bedrock ranges from 20 to 40 inches. In some areas the decreases and the proportion of less preferred forage plants surface layer is gravelly or stony. increases. Permeability is moderate in the Straight soil. Available A planned grazing system that includes timely deferment water capacity is about 3 inches. The effective rooting depth of grazing, rotation grazing, and proper livestock distribution is 20 to 40 inches. Runoff is rapid, and the hazard of water helps to prevent overgrazing of the understory and damage to erosion is high. the soil. Grazing should be delayed until the more desirable The Shippa soil is shallow and well drained. It formed in forage plants have achieved enough growth to withstand colluvium derived dominantly from andesite, tuff, and grazing pressure and the soil is firm enough to withstand breccia. Typically, the surface layer is dark brown extremely trampling by livestock. gravelly loam about 4 inches thick. The subsoil is brown Thinning, logging, and fire reduce the density of the extremely cobbly loam about 12 inches thick. Bedrock is at a overstory canopy and increase the production of understory depth of about 16 inches. The depth to bedrock ranges from vegetation. Areas that support a large amount of competing 12 to 20 inches. In some areas the surface layer is stony. vegetation can be improved by prescribed burning or by Permeability is moderately rapid in the Shippa soil. chemical or mechanical treatment. Seeding disturbed areas Available water capacity is about 1 inch. The effective to suitable plants increases forage production and reduces rooting depth is 12 to 20 inches. Runoff is rapid, and the the risk of erosion. hazard of water erosion is high. The vegetative site is Mixed Fir-Mixed Pine Forest. This unit is used for timber production, livestock grazing, and wildlife habitat. 184G-Straight-Shippa extremely gravelly loams, 35 to This unit is suited to the production of Douglas fir. 70 percent north slopes. This map unit is on hillslopes. Other species that grow on this unit include white fir, Elevation is 2,000 to 4,000 feet. The mean annual incense cedar, and Pacific dogwood. The understory precipitation is 35 to 55 inches, the mean annual temperature vegetation includes Pacific serviceberry, cascade is 45 to 52 degrees F, and the average frost-free period is 100 Oregongrape, and deerfoot vanillaleaf. to 160 days. The native vegetation is mainly conifers and On the basis of a 100-year site curve, the mean site hardwoods and an understory of grasses, shrubs, and forbs. index for Douglas fir is 115 on the Straight soil. The yield at This unit is about 60 percent Straight soil and 20 percent culmination of the mean annual increment is 6,360 cubic Shippa soil. The components of this unit occur as areas so feet per acre in a fully stocked, even-aged stand of trees at intricately intermingled that mapping them separately was 60 years and 50,700 board feet per acre (Scribner rule) at not practical at the scale used. 130 years. On the basis of a 50-year curve, the mean site Included in this unit are small areas of Freezener and index is 85. Geppert soils and Rock outcrop on ridges and convex On the basis of a 100-year site curve, the mean site index for Douglas fir is 85 on the Shippa soil. The yield at culmination of the mean annual increment is 4,480 cubic feet per acre in a fully stocked, even-aged stand of trees at 70 years and 27,520 board feet per acre maintain the moisture supply in summer and minimizes (Scribner rule) at 160 years. On the basis of a 50-year competition from undesirable plants. curve, the mean site index is 60. A high temperature in the surface layer during summer The main limitations affecting timber production are the and the low available water capacity increase the seedling slope, erosion, compaction, plant competition, and mortality rate. The large number of rock fragments in both seedling mortality. Also, the bedrock underlying the Shippa soils and the limited depth of the Shippa soil also increase soil restricts root growth. As a result, windthrow is a the seedling mortality rate. To compensate for the expected hazard. high mortality rate, the larger seedlings or a greater number Wheeled and tracked logging equipment can be used, in of seedlings should be planted. When the timber is the less sloping areas, but cable yarding generally is safer harvested, leaving some of the larger trees unharvested and results in less surface disturbance. If the soils are provides shade for seedlings. excessively disturbed when timber is harvested or logging The main limitations affecting livestock grazing are roads are built, a larger number of rock fragments is left on erosion, compaction, and the slope. The native vegetation the surface. Using standard wheeled and tracked equipment suitable for grazing includes western fescue, mountain when the soils are moist causes rutting and compaction. brome, tall trisetum, and Alaska oniongrass. If the Puddling can occur when the soils are wet. Using understory is overgrazed, the proportion of preferred forage low-pressure ground equipment causes less damage to the plants decreases and the proportion of less preferred forage soils and helps to maintain productivity. Compaction can be plants increases. minimized by using suitable methods of harvesting, laying A planned grazing system that includes timely deferment out skid trails in advance, and harvesting timber when the of grazing, rotation grazing, and proper livestock distribution soils are least susceptible to compaction. Ripping skid trails helps to prevent overgrazing of the understory and damage and landings when the soils are dry can improve the growth to the soils. Grazing should be delayed until the more of plants. desirable forage plants have achieved enough growth to Properly designed road drainage systems that include withstand grazing pressure and the soils are firm enough to carefully located culverts help to control erosion. Areas that withstand trampling by livestock. have been cut and filled are easily eroded unless they are Thinning, logging, and fire reduce the density of the treated. Seeding, mulching, and benching these areas help overstory canopy and increase the production of to control erosion. In areas of the Shippa soil, however, understory vegetation. Areas that support a large amount road cutbanks may not respond well to seeding and of competing vegetation can be improved by prescribed mulching because of the large amount of fractured bedrock burning or by chemical or mechanical treatment. Seeding that is exposed. Steep yarding paths, skid trails, and disturbed areas to suitable plants increases forage firebreaks are subject to rilling and gullying unless they are production and reduces the risk of erosion. protected by a plant cover or adequate water bars, or both. The vegetative site is Mixed Fir-Dogwood Forest. Cutbanks occasionally slump when the soils are saturated. Constructing logging roads on the steeper slopes can 185G-Straight-Shippa extremely gravelly loams, 35 to result in a high risk of erosion. Building the roads at 60 percent south slopes. This map unit is on hillslopes. midslope requires extensive cutting and filling and removes Elevation is 2,000 to 4,000 feet. The mean annual land from production. Material that is discarded when the precipitation is 35 to 55 inches, the mean annual roads are built can damage vegetation and is a potential temperature is 45 to 52 degrees F, and the average source of sedimentation. If the material becomes saturated, frost-free period is 100 to 160 days. The native vegetation is avalanches of debris can occur. End hauling of the waste mainly conifers and hardwoods and an understory of material minimizes damage to the vegetation downslope grasses, shrubs, and forbs. and reduces the risk of sedimentation. Skid trails and This unit is about 55 percent Straight soil and 25 unsurfaced roads may be impassable during rainy periods. percent Shippa soil. The components of this unit occur as Logging roads require suitable surfacing for year-round use. areas so intricately intermingled that mapping them Undesirable plants limit natural or artificial reforestation separately was not practical at the scale used. unless intensive site preparation and maintenance Included in this unit are small areas of Freezener and measures are applied. Reforestation can be accomplished Geppert soils, Rock outcrop on ridges and convex slopes, by planting Douglas fir and ponderosa pine seedlings. soils that are similar to the Straight soil but have bedrock at Mulching around seedlings helps to a depth of more than 40 inches, and soils that are similar to the Shippa soil but have bedrock within a depth of 10 inches. Also included are small areas The main limitations affecting timber production are the of Straight and Shippa soils that have slopes of less than slope, erosion, compaction, seedling mortality, and plant 35 or more than 60 percent. Included areas make up competition. Also, the bedrock underlying the Shippa soil about 20 percent of the total acreage. restricts root growth. As a result, windthrow is a hazard. The Straight soil is moderately deep and well drained. It Wheeled and tracked logging equipment can be used in formed in colluvium derived dominantly from andesite, tuff, the less sloping areas, but cable yarding generally is safer and breccia. Typically, the surface is covered with a layer of and results in less surface disturbance. If the soils are needles, leaves, and twigs about 11/2 inches thick. The excessively disturbed when timber is harvested or logging surface layer is dark reddish brown extremely gravelly loam roads are built, a larger number of rock fragments is left on about 9 inches thick. The next layer is dark brown very the surface. Using standard wheeled and tracked equipment gravelly loam about 10 inches thick. The upper 11 inches of when the soils are moist causes rutting and compaction. the subsoil also is dark brown very gravelly loam. The lower Puddling can occur when the soils are wet. Using 5 inches is dark brown very cobbly clay loam. Weathered low-pressure ground equipment causes less damage to the bedrock is at a depth of about 35 inches. The depth to soils and helps to maintain productivity. Compaction can be bedrock ranges from 20 to 40 inches. In some areas the minimized by using suitable methods of harvesting, laying surface layer is gravelly or stony. out skid trails in advance, and harvesting timber when the Permeability is moderate in the Straight soil, Available soils are least susceptible to compaction. Ripping skid trails water capacity is about 3 inches. The effective rooting depth and landings when the soils are dry can improve the growth is 20 to 40 inches. Runoff is rapid, and the hazard of water of plants. erosion is high. Properly designed road drainage systems that include The Shippa soil is shallow and well drained. It formed in carefully located culverts help to control erosion. Areas that colluvium derived dominantly from andesite, tuff, and have been cut and filled are easily eroded unless they are breccia. Typically, the surface layer is dark brown extremely treated. Seeding, mulching, and benching these areas help gravelly loam about 4 inches thick. The subsoil is brown to control erosion. In areas of the Shippa soil, however, road extremely cobbly loam about 12 inches thick. Bedrock is at cutbanks may not respond well to seeding and mulching a depth of about 16 inches. The depth to bedrock ranges because of the large amount of fractured bedrock that is from 12 to 20 inches. In some areas the surface layer is exposed. Steep yarding paths, skid trails, and firebreaks are stony. subject to rilling and gullying unless they are protected by a Permeability is moderately rapid in the Shippa soil. plant cover or adequate water bars, or both. Cutbanks Available water capacity is about 1 inch. The effective occasionally slump when the soils are saturated. rooting depth is 12 to 20 inches. Runoff is rapid, and the Constructing logging roads on the steeper slopes can hazard of water erosion is high. result in a high risk of erosion. Building the roads at This unit is used for timber production, livestock midslope requires extensive cutting and filling and removes grazing, and wildlife habitat. land from production. Material that is discarded when the This unit is suited to the production of Douglas fir. Other roads are built can damage vegetation and is a potential species that grow on this unit include sugar pine, source of sedimentation. If the material becomes saturated, ponderosa pine, white fir, and California black oak. The avalanches of debris can occur. End hauling of the waste understory vegetation includes Pacific serviceberry, tall material minimizes damage to the vegetation downslope Oregongrape, and western fescue. and reduces the risk of sedimentation. Skid trails and On the basis of a 100-year site curve, the mean site unsurfaced roads may be impassable during rainy periods. index for Douglas fir is 110 on the Straight soil. The yield at Logging roads require suitable surfacing for year-round use. culmination of the mean annual increment is 5,880 cubic A high temperature in the surface layer during summer feet per acre in a fully stocked, even-aged stand of trees at and the low available water capacity increase the seedling 60 years and 48,300 board feet per acre (Scribner rule) at mortality rate. The large number of rock fragments in both 140 years. On the basis of a 50-year curve, the mean site soils and the limited depth of the Shippa soil also increase index is 75. the seedling mortality rate. To compensate for the expected On the basis of a 100-year site curve, the mean site high mortality rate, the larger seedlings or a greater number index for Douglas fir is 85 on the Shippa soil. The yield at of seedlings should be planted. When the timber is culmination of the mean annual increment is 4,480 cubic harvested, feet per acre in a fully stocked, even-aged stand of trees at 70 years and 27,520 board feet per acre (Scribner rule) at 160 years. On the basis of a 50-year curve, the mean site index is 60. leaving some of the larger trees unharvested provides soils and on ridges and convex slopes. Also included are shade for seedlings. The seedling mortality rate also can small areas of soils that are similar to the Tablerock soil but be reduced by providing artificial shade for seedlings. have bedrock within a depth of 60 inches. Included areas Reforestation can be accomplished by planting Douglas make up about 20 percent of the total acreage. fir and ponderosa pine seedlings. The Tablerock soil is very deep and moderately well Undesirable plants limit natural or artificial drained. It formed in colluvium derived dominantly from reforestation unless intensive site preparation and andesite and sandstone. Typically, the surface is covered maintenance measures are applied. Mulching around with a layer of leaves and twigs about 1'/2 inches thick. The seedlings helps to maintain the moisture supply in surface layer is very dark brown gravelly loam about 3 summer and minimizes competition from undesirable inches thick. The next layer is very dark grayish brown very plants. cobbly clay loam about 7 inches thick. The upper 10 inches The main limitations affecting livestock grazing are of the subsoil is dark brown very cobbly clay loam. The erosion, compaction, and the slope. The native vegetation next 18 inches is brown very cobbly clay. The lower 27 suitable for grazing includes western fescue, mountain inches is dark yellowish brown gravelly clay loam and brome, tall trisetum, and Alaska oniongrass. If the gravelly loam. Weathered bedrock is at a depth of about 65 understory is overgrazed, the proportion of preferred forage inches. The depth to bedrock is 60 inches or more. In some plants decreases and the proportion of less preferred forage areas the surface layer is cobbly or stony. plants increases. Permeability is very slow in the Tablerock soil. Available A planned grazing system that includes timely deferment water capacity is about 7 inches. The effective rooting depth of grazing, rotation grazing, and proper livestock distribution is 60 inches or more. Runoff is rapid, and the hazard of helps to prevent overgrazing of the understory and damage water erosion is high. The water table fluctuates between to the soils. Grazing should be delayed until the more depths of 4 and 6 feet from December through April. desirable forage plants have achieved enough growth to Rock outcrop consists of areas of exposed bedrock. withstand grazing pressure and the soils are firm enough to Runoff is very rapid in these areas. withstand trampling by livestock. This unit is used for recreational development and Thinning, logging, and fire reduce the density of the livestock grazing. overstory canopy and increase the production of The main limitations affecting recreational understory vegetation. Areas that support a large amount development are the slope, the Rock outcrop, and the of competing vegetation can be improved by prescribed high content of clay, which makes the soil sticky and burning or by chemical or mechanical treatment. Seeding plastic when wet and thus restricts trafficability. These disturbed areas to suitable plants increases forage limitations restrict the use of this unit mainly to paths and production and reduces the risk of erosion. trails, which should extend across the slope. The steep The vegetative site is Mixed Fir-Mixed Pine Forest. slopes and the Rock outcrop should be avoided unless they are to be highlighted in the development. 186H-Tablerock-Rock outcrop complex, 35 to 110 The main limitations affecting livestock grazing are percent slopes. This map unit is on hillslopes. Elevation is erosion, compaction, the slope, droughtiness, and the Rock 1,250 to 3,600 feet. The mean annual precipitation is 18 to outcrop. The vegetation suitable for grazing includes Idaho 30 inches, the mean annual temperature is 45 to 52 fescue, prairie junegrass, and western fescue. If the range degrees F, and the average frost-free period is 120 to 180 is overgrazed, the proportion of preferred forage plants days. The native vegetation is mainly hardwoods and decreases and the proportion of less preferred forage conifers and an understory of grasses, shrubs, and forbs. plants increases. Grazing should be delayed until the more This unit is about 45 percent Tablerock soil and 35 desirable forage plants have achieved enough growth to percent Rock outcrop. The Tablerock soil has slopes of 35 withstand grazing pressure and the soil is firm enough to to 50 percent, and Rock outcrop has slopes of more than withstand trampling by livestock. 50 percent. The components of this unit occur as areas so This unit is poorly suited to range seeding. The main intricately intermingled that mapping them separately was limitations are the slope, droughtiness, and the Rock not practical at the scale used. outcrop. The plants selected for seeding should be those Included in this unit are small areas of Carney, Darow, that meet the seasonal requirements of livestock or wildlife, and Heppsie soils; soils that are similar to Carney soils or both. but have bedrock at a depth of less than 20 or more than The steeper slopes and the Rock outcrop limit 40 inches; and Brader and Debenger access by livestock. As a result, the less sloping areas efficient application and removal of surface ,irrigation water, tend to be overgrazed. Constructing trails or walkways land leveling is needed. To prevent overirrigation and the allows livestock to graze in areas where access is limited. leaching of plant nutrients, applications of irrigation water Suitable management practices on this unit include should be adjusted to the available water capacity, the rate proper grazing use, deferred grazing, rotation grazing, and of water intake, and the needs of the crop. Because the soil brush control. Areas that support a large amount of is droughty, the applications should be light and frequent. competing vegetation can be improved by chemical or The use of pipe, ditch lining, or drop structures in irrigation mechanical treatment. The use of ground equipment is not ditches reduces water loss and the hazard of erosion. practical because of the Rock outcrop and the slope. Proper stocking rates, pasture rotation, and restricted This unit is limited as a site for livestock watering grazing during wet periods help to keep pastures in good ponds and other water impoundments because of the condition and protect the soil from erosion. Grazing when slope and the Rock outcrop. the soil is wet results in compaction of the surface layer, The vegetative site is Pine-Douglas Fir-Fescue. poor tilth, and excessive runoff. Periodic mowing and clipping help to maintain uniform plant growth, discourage 187A-Takilma cobbly loam, 0 to 3 percent slopes. selective grazing, and reduce the extent of clumpy growth. This very deep, well drained soil is on stream terraces. It Fertilizer is needed to ensure the optimum growth of formed in alluvium derived from mixed sources. Elevation grasses and legumes. Grasses respond to nitrogen, and is 1,000 to 2,500 feet. The mean annual precipitation is 20 legumes respond to sulfur and phosphorus. to 35 inches, the mean annual temperature is 50 to 54 The main limitations affecting homesite development degrees F, and the average frost-free period is 140 to 180 are the moderately rapid permeability and the large days. The native vegetation is mainly hardwoods and an number of rock fragments on and below the surface. understory of grasses, shrubs, and forbs. The suitability of this unit for septic tank absorption Typically, the surface layer is very dark grayish brown fields is limited because the extremely gravelly cobbly loam about 6 inches thick. The upper 9 inches of substratum has a poor filtering capacity. Alternative the subsoil is very dark grayish brown very cobbly loam. waste disposal systems may function properly on this The lower 9 inches is brown extremely cobbly sandy unit. Suitable included soils are throughout the unit. loam. The substratum to a depth of 60 inches is dark Onsite investigation is needed to locate such soils. yellowish brown and brown extremely gravelly and very Establishing plants is difficult in areas where the surface gravelly sandy loam. layer has been removed. Mulching and applying fertilizer Included in this unit are small areas of Evans, Newberg, help to establish plants in cut areas. Gravel and cobbles and Camas soils on flood plains; Medford soils on the lower should be removed from disturbed areas, particularly areas terraces; poorly drained soils near drainageways; Central used for lawns. Topsoil can be stockpiled and used to Point and Foehlin soils; and soils that are similar to the reclaim areas disturbed during construction. In many areas Takilma soil but have a substratum of very gravelly sand. it may be necessary to haul in topsoil for lawns and Also included are small areas of Takilma soils that have gardens. Because of droughtiness and a low amount of slopes of more than 3 percent. Included areas make up rainfall in summer, irrigation is needed in areas that support about 15 percent of the total acreage. lawn grasses, shrubs, vines, shade trees, or ornamental Permeability is moderately rapid in the Takilma soil. trees. Available water capacity is about 4 inches. The effective The main limitations affecting livestock grazing are rooting depth is 60 inches or more. Runoff is slow, and the compaction, the cobbly surface layer, and droughtiness. hazard of water erosion is slight. The vegetation suitable for grazing includes Idaho fescue, This unit is used mainly for hay and pasture. It also is tall trisetum, and western fescue. If the range is overgrazed, used for homesite development and livestock grazing. the proportion of preferred forage plants decreases and the This unit is suited to hay and pasture. The main proportion of less preferred forage plants increases. limitations are droughtiness and cobbles on the surface. Grazing should be delayed until the soil is firm and the more The cobbles limit the use of equipment in some areas. In desirable forage plants have achieved enough growth to summer, irrigation is needed for the maximum production of withstand grazing pressure. most forage crops. Sprinkler irrigation is the best method of Range seeding is suitable if the site is in poor condition. applying water. Border and contour flood irrigation systems The main limitations are the cobbly surface layer and also are suitable. For the droughtiness. The plants selected for seeding should be those that meet the seasonal requirements of livestock or wildlife, or both. Suitable management practices on this unit include years. On the basis of a 50-year curve, the mean site proper grazing use, deferred grazing, rotation grazing, and index is 70. brush control. Areas that support a large amount of On the basis of a 100-year site curve, the mean site competing vegetation can be improved by chemical or index for ponderosa pine is 100. The yield at culmination mechanical treatment. In places the use of ground of the mean annual increment is 4,080 cubic feet per acre equipment is limited by the cobbles on the surface. in a fully stocked, even-aged stand of trees at 40 years This unit is limited as a site for livestock watering and 44,640 board feet per acre (Scribner rule) at 120 ponds and other water impoundments because of years. seepage. The main limitations affecting timber production are The vegetative site is Pine-Douglas Fir-Fescue. erosion, compaction, plant competition, and seedling mortality. Also, the bedrock restricts root growth. As a 188E-Tallowbox gravelly sandy loam, 20 to 35 result, windthrow is a hazard. percent north slopes. This moderately deep, somewhat When timber is harvested, management that minimizes excessively drained soil is on hillslopes and ridges. It formed the risk of erosion is essential. Wheeled and tracked logging in colluvium derived from granitic rock. Elevation is 1,000 to equipment can be used in the less sloping areas, but cable 4,000 feet. The mean annual precipitation is 25 to 40 yarding generally is safer in the more sloping areas and inches, the mean annual temperature is 46 to 54 degrees F, results in less surface disturbance. Using standard wheeled and the average frost-free period is 100 to 160 days. The and tracked equipment when the soil is moist causes rutting native vegetation is mainly conifers and hardwoods and an and compaction. Puddling can occur when the soil is wet. understory of grasses, shrubs, and forbs. Using low-pressure ground equipment causes less damage Typically, the surface is covered with a layer of needles, to the soil and helps to maintain productivity. Compaction leaves, and twigs about 1 inch thick. The surface layer is can be minimized by using suitable methods of harvesting, dark brown gravelly sandy loam about 6 inches thick. The laying out skid trails in advance, and harvesting timber when upper 6 inches of the subsoil is dark brown sandy loam. the soil is least susceptible to compaction. Ripping skid trails The lower 11 inches is brown gravelly sandy loam. and landings when the soil is dry can improve the growth of Weathered bedrock is at a depth of about 23 inches. The plants. depth to bedrock ranges from 20 to 40 inches. Properly designed road drainage systems that include Included in the unit are small areas of Offenbacher, carefully located culverts help to control erosion. Areas that Shefflein, and Vannoy soils; Caris and Voorhies soils on the have been cut and filled are easily eroded unless they are more sloping parts of the landscape; Ruch soils on toe treated. Seeding, mulching, and benching these areas help slopes; poorly drained soils near drainageways and on to control erosion. Steep yarding paths, skid trails, and concave slopes; and soils that are similar to the Tallowbox firebreaks are subject to rilling and gullying unless they are soil but have bedrock at a depth of less than 20 or more protected by a plant cover or adequate water bars, or both. than 40 inches. Also included are small areas of Tallowbox Cutbanks occasionally slump when the soil is saturated. soils that have slopes of less than 20 or more than 35 . This unit is subject to slumping, especially in areas percent. Included areas make up about 15 percent of the adjacent to drainageways. Road failure and landslides are total acreage. likely to occur after road construction and clearcutting. Skid Permeability is moderately rapid in the Tallowbox trails and unsurfaced roads may be impassable during soil. Available water capacity is about 3 inches. The rainy periods. Logging roads require suitable surfacing for effective rooting depth is 20 to 40 inches. Runoff is year-round use. medium, and the hazard of water erosion is high. Undesirable plants limit natural or artificial reforestation This unit is used for timber production and wildlife unless intensive site preparation and maintenance habitat. It is suited to the production of Douglas fir and measures are applied. Reforestation can be accomplished ponderosa pine. Other species that grow on this unit include by planting Douglas fir and ponderosa pine seedlings. incense cedar, sugar pine, and Pacific madrone. The Mulching around seedlings helps to maintain the moisture understory vegetation includes creambush oceanspray, supply in summer and minimizes competition from common snowberry, and tall Oregongrape. undesirable plants. On the basis of a 100-year site curve, the mean site A high temperature in the surface layer during summer index for Douglas fir is 100. The yield at culmination of the and the low available water capacity increase the seedling mean annual increment is 5,040 cubic feet per acre in a mortality rate. To compensate for the expected high fully stocked, even-aged stand of trees at 60 years and mortality rate, the larger seedlings or a greater number of 39,750 board feet per acre (Scribner rule) at 150 seedlings should be planted. When the timber is harvested, leaving some of the larger trees of trees at 40 years and 44,640 board feet per acre unharvested provides shade for seedlings. (Scribner rule) at 120 years. Increased erosion, loss of plant nutrients, and water The main limitations affecting timber production are the repellency are likely to result from fires of moderate slope, erosion, compaction, plant competition, and intensity. seedling mortality. Also, the bedrock restricts root growth. The vegetative site is Douglas Fir Forest. As a result, windthrow is a hazard. When timber is harvested, management that minimizes 188G-Tallowbox gravelly sandy loam, 35 to 70 the risk of erosion is essential. Wheeled and tracked logging percent north slopes. This moderately deep, somewhat equipment can be used in the less sloping areas, but cable excessively drained soil is on hillslopes. It formed in yarding generally is safer and results in less surface colluvium derived from granitic rock. Elevation is 1,000 to disturbance. Using standard wheeled and tracked 4,000 feet. The mean annual precipitation is 25 to 40 inches, equipment when the soil is moist causes rutting and the mean annual temperature is 46 to 54 degrees F, and the compaction. Puddling can occur when the soil is wet. Using average frost-free period is 100 to 160 days. The native low-pressure ground equipment causes less damage to the vegetation is mainly conifers and hardwoods and an soil and helps to maintain productivity. Compaction can be understory of grasses, shrubs, and forbs. minimized by using suitable methods of harvesting, laying Typically, the surface is covered with a layer of needles, out skid trails in advance, and harvesting timber when the leaves, and twigs about 1 inch thick. The surface layer is soil is least susceptible to compaction. Ripping skid trails dark brown gravelly sandy loam about 6 inches thick. The and landings when the soil is dry can improve the growth of upper 6 inches of the subsoil is dark brown sandy loam. The plants. lower 11 inches is brown gravelly sandy loam. Weathered Properly designed road drainage systems that include bedrock is at a depth of about 23 inches. The depth to carefully located culverts help to control erosion. Areas that bedrock ranges from 20 to 40 inches. have been cut and filled are easily eroded unless they are Included in this unit are small areas of Caris, treated. Seeding, mulching, and benching these areas help Offenbacher, Vannoy, and Voorhies soils; soils that are to control erosion. Steep yarding paths, skid trails, and similar to the Tallowbox soil but have bedrock at a depth of firebreaks are subject to rilling and gullying unless they are less than 20 or more than 40 inches; and Tallowbox soils protected by a plant cover or adequate water bars, or both. that have slopes of less than 35 or more than 70 percent. Cutbanks occasionally slump when the soil is saturated. Included areas make up about 15 percent of the total This unit is subject to slumping, especially in areas acreage. adjacent to drainageways. Road failure and landslides are Permeability is moderately rapid in the Tallowbox likely to occur after road construction and clearcutting. soil. Available water capacity is about 3 inches. The Constructing logging roads on the steeper slopes can effective rooting depth is 20 to 40 inches. Runoff is result in a high risk of erosion. Building the roads at rapid, and the hazard of water erosion is high. midslope requires extensive cutting and filling and removes This unit is used for timber production and wildlife land from production. Material that is discarded when the habitat. It is suited to the production of Douglas fir and roads are built can damage vegetation and is a potential ponderosa pine. Other species that grow on this unit include source of sedimentation. If the material becomes saturated, incense cedar, sugar pine, and Pacific madrone. The avalanches of debris can occur. End hauling of the waste understory vegetation includes creambush oceanspray, material minimizes damage to the vegetation downslope common snowberry, and tall Oregongrape. and reduces the risk of sedimentation. Skid trails and On the basis of a 100-year site curve, the mean site unsurfaced roads may be impassable during rainy periods. index for Douglas fir is 100. The yield at culmination of the Logging roads require suitable surfacing for year-round use. mean annual increment is 5,040 cubic feet per acre in a Undesirable plants limit natural or artificial reforestation fully stocked, even-aged stand of trees at 60 years and unless intensive site preparation and maintenance 39,750 board feet per acre (Scribner rule) at 150 years. On measures are applied. Reforestation can be accomplished the basis of a 50-year curve, the mean site index is 70. by planting Douglas fir and ponderosa pine seedlings. On the basis of a 100-year site curve, the mean site Mulching around seedlings helps to maintain the moisture index for ponderosa pine is 100. The yield at culmination of supply in summer and minimizes competition from the mean annual increment is 4,080 cubic feet per acre in undesirable plants. a fully stocked, even-aged stand A high temperature in the surface layer during summer and the low available water capacity increase the years and 37,960 board feet per acre (Scribner rule) at 130 seedling mortality rate. To compensate for the expected years. high mortality rate, the larger seedlings or a greater number On the basis of a 100-year site curve, the mean site of seedlings should be planted. When the timber is index for Douglas fir is 90. The yield at culmination of the harvested, leaving some of the larger trees unharvested mean annual increment is 4,200 cubic feet per acre in a provides shade for seedlings. fully stocked, even-aged stand of trees at 60 years and Increased erosion, loss of plant nutrients, and water 31,840 board feet per acre (Scribner rule) at 160 years. On repellency are likely to result from fires of moderate the basis of a 50-year curve, the mean site index is 60. intensity. The main limitations affecting timber production are The vegetative site is Douglas Fir Forest. erosion, compaction, seedling mortality, and plant competition. Also, the bedrock restricts root growth. As a 189E-Tallowbox gravelly sandy loam, 20 to 35 result, windthrow is a hazard. percent south slopes. This moderately deep, somewhat When timber is harvested, management that minimizes excessively drained soil is on hillslopes and ridges. It the risk of erosion is essential. Wheeled and tracked logging formed in colluvium derived from granitic rock. Elevation is equipment can be used in the less sloping areas, but cable 1,000 to 4,000 feet. The mean annual precipitation is 25 to yarding generally is safer in the more sloping areas and 40 inches, the mean annual temperature is 46 to 54 results in less surface disturbance. Using standard wheeled degrees F, and the average frost-free period is 100 to 160 and tracked equipment when the soil is moist causes rutting days. The native vegetation is mainly conifers and and compaction. Puddling can occur when the soil is wet. hardwoods and an understory of grasses, shrubs, and Using low-pressure ground equipment causes less damage forbs. to the soil and helps to maintain productivity. Compaction Typically, the surface is covered with a layer of needles, can be minimized by using suitable methods of harvesting, leaves, and twigs about 1 inch thick. The surface layer is laying out skid trails in advance, and harvesting timber when dark brown gravelly sandy loam about 6 inches thick. The the soil is least susceptible to compaction. Ripping skid trails upper 6 inches of the subsoil is dark brown sandy loam. The and landings when the soil is dry can improve the growth of lower 11 inches is brown gravelly sandy loam. Weathered plants. bedrock is at a depth of about 23 inches. The depth to Properly designed road drainage systems that include bedrock ranges from 20 to 40 inches. carefully located culverts help to control erosion. Areas that Included in the unit are small areas Offenbacher and have been cut and filled are easily eroded unless they are Vannoy soils, soils that are similar to the Tallowbox soil but treated. Seeding, mulching, and benching these areas help have bedrock at a depth of less than 20 or more than 40 to control erosion. Steep yarding paths, skid trails, and inches, Caris and Voorhies soils on the more sloping parts firebreaks are subject to rilling and gullying unless they are of the landscape, Ruch soils on toe slopes, and poorly protected by a plant cover or adequate water bars, or both. drained soils near drainageways and on concave slopes. Cutbanks occasionally slump when the soil is saturated. Also included are small areas of Tallowbox soils that have This unit is subject to slumping, especially in areas slopes of less than 20 or more than 35 percent. Included adjacent to drainageways. Road failure and landslides are areas make up about 15 percent of the total acreage. likely to occur after road construction and clearcutting. Skid Permeability is moderately rapid in the Tall owbox trails and unsurfaced roads may be impassable during soil. Available water capacity is about 3 inches. The rainy periods. Logging roads require suitable surfacing for effective rooting depth is 20 to 40 inches. Runoff is year-round use. medium, and the hazard of water erosion is high. A high temperature in the surface layer during summer This unit is used for timber production and wildlife and the low available water capacity increase the seedling habitat. It is suited to the production of ponderosa pine and mortality rate. To compensate for the expected high Douglas fir. Other species that grow on this unit include mortality rate, the larger seedlings or a greater number of incense cedar, sugar pine, and Pacific madrone. The seedlings should be planted. When the timber is harvested, understory vegetation includes deerbrush, tall Oregongrape, leaving some of the larger trees unharvested provides and Idaho fescue. shade for seedlings. The seedling mortality rate also can be On the basis of a 100-year site curve, the mean site reduced by providing artificial shade for seedlings. index for ponderosa pine is 90. The yield at culmination of Reforestation can be accomplished by planting Douglas fir the mean annual increment is 3,400 cubic feet per acre in a and ponderosa pine seedlings. fully stocked, even-aged stand of trees at 40 Undesirable plants limit natural or artificial reforestation unless intensive site preparation and index for Douglas fir is 90. The yield at culmination of the maintenance measures are applied. Mulching around mean annual increment is 4,200 cubic feet per acre in a seedlings helps to maintain the moisture supply in fully stocked, even-aged stand of trees at 60 years and summer and minimizes competition from undesirable 31,840 board feet per acre (Scribner rule) at 160 years. On plants. the basis of a 50-year curve, the mean site index is 60. Increased erosion, loss of plant nutrients, and water The main limitations affecting timber production are the repellency are likely to result from fires of moderate slope, erosion, compaction, seedling mortality, and plant intensity. competition. Also, the bedrock restricts root growth. As a The vegetative site is Mixed Pine-Douglas Fir-Fescue result, windthrow is a hazard. Forest, Granitic. When timber is harvested, management that minimizes the risk of erosion is essential. Wheeled and tracked 189G-Tallowbox gravelly sandy loam, 35 to 60 logging equipment can be used in the less sloping areas, percent south slopes. This moderately deep, somewhat but cable yarding generally is safer and results in less excessively drained soil is on hillslopes. It formed in surface disturbance. Using standard wheeled and tracked colluvium derived from granitic rock. Elevation is 1,000 to equipment when the soil is moist causes rutting and 4,000 feet. The mean annual precipitation is 25 to 40 compaction. Puddling can occur when the soil is wet. Using inches, the mean annual temperature is 46 to 54 degrees F, low-pressure ground equipment causes less damage to the and the average frost-free period is 100 to 160 days. The soil and helps to maintain productivity. Compaction can be native vegetation is mainly conifers and hardwoods and an minimized by using suitable methods of harvesting, laying understory of grasses, shrubs, and forbs. out skid trails in advance, and harvesting timber when the Typically, the surface is covered with a layer of needles, soil is least susceptible to compaction. Ripping skid trails leaves, and twigs about 1 inch thick. The surface layer is and landings when the soil is dry can improve the growth of dark brown gravelly sandy loam about 6 inches thick. The plants. upper 6 inches of the subsoil is dark brown sandy loam. The Properly designed road drainage systems that include lower 11 inches is brown gravelly sandy loam. Weathered carefully located culverts help to control erosion. Areas that bedrock is at a depth of about 23 inches. The depth to have been cut and filled are easily eroded unless they are bedrock ranges from 20 to 40 inches. treated. Seeding, mulching, and benching these areas help Included in this unit are small areas of Caris, to control erosion. Steep yarding paths, skid trails, and Offenbacher, Vannoy, and Voorhies soils on concave firebreaks are subject to rilling and gullying unless they are slopes or on the less sloping parts of the landscape; soils protected by a plant cover or adequate water bars, or both. that are similar to the Tallowbox soil but have bedrock at a Cutbanks occasionally slump when the soil is saturated. depth of less than 20 or more than 40 inches; and This unit is subject to slumping, especially in areas Tallowbox soils that have slopes of less than 35 or more adjacent to drainageways. Road failure and landslides are than 70 percent. Included areas make up about 15 percent likely to occur after road construction and clearcutting. of the total acreage. Constructing logging roads on the steeper slopes can Permeability is moderately rapid in the Tallowbox result in a high risk of erosion. Building the roads at soil. Available water capacity is about 3 inches. The midslope requires extensive cutting and filling and removes effective rooting depth is 20 to 40 inches. Runoff is land from production. Material that is discarded when the rapid, and the hazard of water erosion is high. roads are built can damage vegetation and is a potential This unit is used for timber production and wildlife habitat. source of sedimentation. If the material becomes saturated, It is suited to the production of ponderosa pine and Douglas avalanches of debris can occur. End hauling of the waste fir. Other species that grow on this unit include incense material minimizes damage to the vegetation downslope cedar, sugar pine, and Pacific madrone. The understory and reduces the risk of sedimentation. Skid trails and vegetation includes deerbrush, tall Oregongrape, and Idaho unsurfaced roads may be impassable during rainy periods. fescue. Logging roads require suitable surfacing for year-round use. On the basis of a 100-year site curve, the mean site A high temperature in the surface layer during summer index for ponderosa pine is 90. The yield at culmination of and the low available water capacity increase the seedling the mean annual increment is 3,400 cubic feet per acre in a mortality rate. To compensate for the expected high fully stocked, even-aged stand of trees at 40 years and mortality rate, the larger seedlings or a 37,960 board feet per acre (Scribner rule) at 130 years. On the basis of a 100-year site curve, the mean site greater number of seedlings should be planted. When the understory vegetation includes creambush oceanspray, timber is harvested, leaving some of the larger trees cascade Oregongrape, and whitevein shinleaf. unharvested provides shade for seedlings. The seedling On the basis of a 100-year site curve, the mean site mortality rate also can be reduced by providing artificial index for Douglas fir is 125. The yield at culmination of the shade for seedlings. Reforestation can be accomplished by mean annual increment is 7,320 cubic feet per acre in a planting Douglas fir and ponderosa pine seedlings. fully stocked, even-aged stand of trees at 60 years and Undesirable plants limit natural or artificial 58,200 board feet per acre (Scribner rule) at 120 years. On reforestation unless intensive site preparation and the basis of a 50-year curve, the mean site index is 90. maintenance measures are applied. Mulching around The main limitations affecting timber production are seedlings helps to maintain the moisture supply in erosion, compaction, plant competition, and seedling summer and minimizes competition from undesirable mortality. Wheeled and tracked logging equipment can be plants. used in the less sloping areas, but cable yarding generally Increased erosion, loss of plant nutrients, and water is safer in the more sloping areas and results in less repellency are likely to result from fires of moderate surface disturbance. Using standard wheeled and tracked intensity. equipment when the soil is moist causes rutting and The vegetative site is Mixed Pine-Douglas Fir-Fescue compaction. Puddling can occur when the soil is wet. Using Forest, Granitic. low-pressure ground equipment causes less damage to the soil and helps to maintain productivity. Compaction can be 190E-Tatouche gravelly loam, 12 to 35 percent north minimized by using suitable methods of harvesting, laying slopes. This very deep, well drained soil is on hillslopes. It out skid trails in advance, and harvesting timber when the formed in colluvium derived dominantly from andesite, tuff, soil is least susceptible to compaction. Ripping skid trails and breccia. Elevation is 3,600 to 5,500 feet. The mean and landings when the soil is dry can improve the growth of annual precipitation is 30 to 50 inches, the mean annual plants. temperature is 40 to 45 degrees F, and the average Properly designed road drainage systems that include frost-free period is less than 100 days. The native carefully located culverts help to control erosion Seeding, vegetation is mainly conifers and an understory of grasses, mulching, and benching areas that have been cut and filled shrubs, and forbs. also help to control erosion. Steep yarding paths, skid trails, Typically, the surface is covered with a layer of needles and firebreaks are subject to rilling and gullying unless they and twigs about 2 inches thick. The surface layer is very are protected by a plant cover or adequate water bars, or dark brown gravelly loam about 11 inches thick. The upper both. Skid trails and unsurfaced roads may be impassable 8 inches of the subsoil is dark brown gravelly clay loam. during rainy periods. Logging roads require suitable The lower 41 inches is dark brown clay. The substratum to surfacing for year-round use. a depth of 73 inches is strong brown clay loam. The depth Undesirable plants limit natural or artificial reforestation to bedrock is 60 inches or more. In some areas the surface unless intensive site preparation and maintenance layer is stony or cobbly. measures are applied. Reforestation can be accomplished Included in this unit are small areas of Pinehurst soils; by planting ponderosa pine and Douglas fir seedlings. Bybee, Kanutchan, and Sibannac soils near drainageways Mulching around seedlings helps to maintain the moisture and on concave slopes; Farva soils on convex slopes; and supply in summer and minimizes competition from soils that are similar to the Tatouche soil but have bedrock undesirable plants. within a depth of 60 inches -Also included are small areas of Severe frost can damage or kill seedlings. In the less Tatouche soils that have slopes of less than 12 or more sloping areas where air drainage may be restricted, proper than 35 percent. Included areas make up about 20 percent timber harvesting methods can reduce the effect of frost on of the total acreage. regeneration. Permeability is moderately slow in the Tatouche soil. The main limitations affecting livestock grazing are Available water capacity is about 8 inches. The effective compaction and erosion. The native vegetation suitable for rooting depth is 60 inches or more. Runoff is medium, and grazing includes western fescue, mountain brome, and the hazard of water erosion is moderate. Alaska oniongrass. If the understory is overgrazed, the This unit is used for timber production, livestock proportion of preferred forage plants decreases and the grazing, and wildlife habitat. proportion of less preferred forage plants increases. This unit is suited to the production of Douglas fir A planned grazing system that includes timely and white fir. Other species that grow on this unit deferment of grazing, rotation grazing, and proper include incense cedar and ponderosa pine. The livestock distribution helps to prevent overgrazing of the On the basis of a 100-year site curve, the mean site understory and damage to the soil. Grazing should be index for Douglas fir is 120. The yield at culmination of the delayed until the more desirable forage plants have mean annual increment is 6,900 cubic feet per acre in a achieved enough growth to withstand grazing pressure and fully stocked, even-aged stand of trees at 60 years and the soil is firm enough to withstand trampling by livestock. 52,440 board feet per acre (Scribner rule) at 120 years. On Thinning, logging, and fire reduce the density of the the basis of a 50-year curve, the mean site index is 90. overstory canopy and increase the production of The main limitations affecting timber production are the understory vegetation. Areas that support a large amount slope, erosion, compaction, plant competition, and seedling of competing vegetation can be improved by prescribed mortality. Wheeled and tracked logging equipment can be burning or by chemical or mechanical treatment. Seeding used in the less sloping areas, but cable yarding generally disturbed areas to suitable plants increases forage is safer and results in less surface disturbance. Using production and reduces the risk of erosion. standard wheeled and tracked equipment when the soil is The vegetative site is Mixed Fir-Oceanspray Forest. moist causes rutting and compaction. Puddling can occur when the soil is wet. Using low-pressure ground equipment 190G-Tatouche gravelly loam, 35 to 65 percent north causes less damage to the soil and helps to maintain slopes. This very deep, well drained soil is on hillslopes. It productivity. Compaction can be minimized by using formed in colluvium derived dominantly from andesite, tuff, suitable methods of harvesting, laying out skid trails in and breccia. Elevation is 3,600 to 5,500 feet. The mean advance, and harvesting timber when the soil is least annual precipitation is 30 to 50 inches, the mean annual susceptible to compaction. Ripping skid trails and landings temperature is 40 to 45 degrees F, and the average when the soil is dry can improve the growth of plants. frost-free period is less than 100 days. The native Properly designed road drainage systems that include vegetation is mainly conifers and an understory of grasses, carefully located culverts help to control erosion Seeding, shrubs, and forbs. mulching, and benching areas that have been cut and filled Typically, the surface is covered with a layer of needles also help to control erosion. Steep yarding paths, skid trails, and twigs about 2 inches thick. The surface layer is very and firebreaks are subject to rilling and gullying unless they dark brown gravelly loam about 11 inches thick. The upper are protected by a plant cover or adequate water bars, or 8 inches of the subsoil is dark brown gravelly clay loam. both. Cutbanks occasionally slump when the soil is The lower 41 inches is dark brown clay. The substratum to saturated. a depth of 73 inches is strong brown clay loam. The depth Constructing logging roads on the steeper slopes can to bedrock is 60 inches or more. In some areas the result in a high risk of erosion. Building the roads at surface layer is stony or cobbly. midslope requires extensive cutting and filling and removes Included in this unit are small areas of Bybee and land from production. Material that is discarded when the Pinehurst soils on concave slopes and on the less sloping roads are built can damage vegetation and is a potential parts of the landscape, Woodseye and Farva soils and source of sedimentation. If the material becomes saturated, Rock outcrop on ridges and convex slopes, and soils that avalanches of debris can occur. End hauling of the waste are similar to the Tatouche soil but have bedrock within a material minimizes damage to the vegetation downslope depth of 60 inches. Also included are small areas of and reduces the risk of sedimentation. Skid trails and Tatouche soils that have slopes of less than 35 or more unsurfaced roads may be impassable during rainy periods. than 65 percent. Included areas make up about 20 percent Logging roads require suitable surfacing for year-round use. of the total acreage. Undesirable plants limit natural or artificial reforestation Permeability is moderately slow in the Tatouche soil. unless intensive site preparation and maintenance Available water capacity is about 8 inches. The effective measures are applied. Reforestation can be accomplished rooting depth is 60 inches or more. Runoff is rapid, and the by planting ponderosa pine and Douglas fir seedlings. hazard of water erosion is high. Mulching around seedlings helps to maintain the moisture This unit is used for timber production, livestock supply in summer and minimizes competition from grazing, and wildlife habitat. undesirable plants. This unit is suited to the production of Douglas fir and Severe frost can damage or kill seedlings. Proper timber white fir. Other species that grow on this unit include harvesting methods can reduce the effect of frost on incense cedar and ponderosa pine. The understory regeneration. vegetation includes creambush oceanspray, cascade The main limitations affecting livestock grazing are Oregongrape, and whitevein shinleaf. erosion, compaction, and the slope. The native vegetation suitable for grazing includes western fescue, This unit is used for timber production, livestock mountain brome, and Alaska oniongrass. If the understory grazing, and wildlife habitat. is overgrazed, the proportion of preferred forage plants This unit is suited to the production of Douglas fir and decreases and the proportion of less preferred forage white fir. Other species that grow on this unit include plants increases. incense cedar and ponderosa pine. The understory A planned grazing system that includes timely deferment vegetation includes Pacific serviceberry, tall Oregongrape, of grazing, rotation grazing, and proper livestock distribution and common snowberry. helps to prevent overgrazing of the understory and damage On the basis of a 100-year site curve, the mean site to the soil. Grazing should be delayed until the soil is firm index for Douglas fir is 110. The yield at culmination of the and the more desirable forage plants have achieved mean annual increment is 5,880 cubic feet per acre in a enough growth to withstand grazing pressure. fully stocked, even-aged stand of trees at 60 years and Thinning, logging, and fire reduce the density of the 48,300 board feet per acre (Scribner rule) at 140 years. On overstory canopy and increase the production of the basis of a 50-year curve, the mean site index is 85. understory vegetation. Areas that support a large amount The main limitations affecting timber production are of competing vegetation can be improved by prescribed erosion, compaction, seedling mortality, and plant burning or by chemical or mechanical treatment. Seeding competition. Wheeled and tracked logging equipment can disturbed areas to suitable plants increases forage be used in the less sloping areas, but cable yarding production and reduces the risk of erosion. generally is safer in the more sloping areas and results in The vegetative site is Mixed Fir-Oceanspray Forest. less surface disturbance. Using standard wheeled and tracked equipment when the soil is moist causes rutting and 191E-Tatouche gravelly loam, 12 to 35 percent compaction. Puddling can occur when the soil is wet. Using south slopes. This very deep, well drained soil is on low-pressure ground equipment causes less damage to the hillslopes. It formed in colluvium derived dominantly from soil and helps to maintain productivity. Compaction can be andesite, tuff, and breccia. Elevation is 3,600 to 5,500 feet. minimized by using suitable methods of harvesting, laying The mean annual precipitation is 30 to 50 inches, the mean out skid trails in advance, and harvesting timber when the annual temperature is 40 to 45 degrees F, and the average soil is least susceptible to compaction. Ripping skid trails frost-free period is less than 100 days. The native and landings when the soil is dry can improve the growth of vegetation is mainly conifers and an understory of grasses, plants. shrubs, and forbs. Properly designed road drainage systems that include Typically, the surface is covered with a layer of needles carefully located culverts help to control erosion Seeding, and twigs about 2 inches thick. The surface layer is very mulching, and benching areas that have been cut and filled dark brown gravelly loam about 11 inches thick. The upper also help to control erosion. Steep yarding paths, skid trails, 8 inches of the subsoil is dark brown gravelly clay loam. and firebreaks are subject to rilling and gullying unless they The lower 41 inches is dark brown clay. The substratum to are protected by a plant cover or adequate water bars, or a depth of 73 inches is strong brown clay loam. The depth both. Skid trails and unsurfaced roads may be impassable to bedrock is 60 inches or more. In some areas the during rainy periods. Logging roads require suitable surface layer is stony or cobbly. surfacing for year-round use. Included in this unit are small areas of Pinehurst soils; A high temperature in the surface layer and an Bybee, Kanutchan, and Sibannac soils near drainageways insufficient moisture supply in summer increase the and on concave slopes; Farva soils and Rock outcrop on seedling mortality rate. To compensate for the expected ridges and convex slopes; and soils that are similar to the high mortality rate, the larger seedlings or a greater number Tatouche soil but have bedrock within a depth of 60 inches. of seedlings should be planted. When the timber is Also included are small areas of Tatouche soils that have harvested, leaving some of the larger trees unharvested slopes of less than 12 or more than 35 percent. Included provides shade for seedlings. Reforestation can be areas make up about 20 percent of the total acreage. accomplished by planting Douglas fir and ponderosa pine Permeability is moderately slow in the Tatouche soil. seedlings. Available water capacity is about 6.5 to 11 inches. The Severe frost can damage or kill seedlings. In the less effective rooting depth is 60 inches or more. Runoff is sloping areas where air drainage may be restricted, proper medium, and the hazard of water erosion is moderate. timber harvesting methods can reduce the effect of frost on regeneration. Undesirable plants limit natural or artificial reforestation unless intensive site preparation and small areas of Tatouche soils that have slopes of less than maintenance measures are applied. Mulching around 35 or more than 60 percent. Included areas make up about seedlings helps to maintain the moisture supply in 20 percent of the total acreage. summer and minimizes competition from undesirable Permeability is moderately slow in the Tatouche soil. plants. Available water capacity is about 8 inches. The effective The main limitations affecting livestock grazing are rooting depth is 60 inches or more. Runoff is rapid, and the compaction and erosion. The native vegetation suitable for hazard of water erosion is high. grazing includes western fescue, mountain brome, tall This unit is used for timber production, livestock trisetum, and Alaska oniongrass. If the understory is grazing, and wildlife habitat. overgrazed, the proportion of preferred forage plants This unit is suited to the production of Douglas fir and decreases and the proportion of less preferred forage white fir. Other species that grow on this unit include plants increases. incense cedar and ponderosa pine. The understory A planned grazing system that includes timely deferment vegetation includes Pacific serviceberry, tall Oregongrape, of grazing, rotation grazing, and proper livestock and common snowberry. distribution helps to prevent overgrazing of the understory On the basis of a 100-year site curve, the mean site and damage to the soil. Grazing should be delayed until the index for Douglas fir is 105. The yield at culmination of the more desirable forage plants have achieved enough growth mean annual increment is 5,460 cubic feet per acre in a to withstand grazing pressure and the soil is firm enough to fully stocked, even-aged stand of trees at 60 years and withstand trampling by livestock. 45,600 board feet per acre (Scribner rule) at 150 years. On Thinning, logging, and fire reduce the density of the the basis of a 50-year curve, the mean site index is 80. overstory canopy and increase the production of The main limitations affecting timber production are the understory vegetation. Areas that support a large amount slope, erosion, compaction, seedling mortality, and plant of competing vegetation can be improved by prescribed competition. Wheeled and tracked logging equipment can burning or by chemical or mechanical treatment. Seeding be used in the less sloping areas, but cable yarding disturbed areas to suitable plants increases forage generally is safer and results, in less surface disturbance. production and reduces the risk of erosion. Using standard wheeled and tracked equipment when the The vegetative site is Mixed Fir-Serviceberry Forest. soil is moist causes rutting and compaction. Puddling can occur when the soil is wet. Using low-pressure ground 191G-Tatouche gravelly loam, 35 to 60 percent equipment causes less damage to the soil and helps to south slopes. This very deep, well drained soil is on maintain productivity. Compaction can be minimized by hillslopes. It formed in colluvium derived dominantly from using suitable methods of harvesting, laying out skid trails in andesite, tuff, and breccia. Elevation is 3,600 to 5,500 feet. advance, and harvesting timber when the soil is least The mean annual precipitation is 30 to 50 inches, the susceptible to compaction. Ripping skid trails and landings mean annual temperature is 40 to 45 degrees F, and the when the soil is dry can improve the growth of plants. average frost-free period is less than 100 days. The native Properly designed road drainage systems that include vegetation is mainly conifers and an understory of grasses, carefully located culverts help to control erosion. Seeding, shrubs, and forbs. mulching, and benching areas that have been cut and filled Typically, the surface is covered with a layer of needles also help to control erosion. Steep yarding paths, skid trails, and twigs about 2 inches thick. The surface layer is very and firebreaks are subject to rilling and gullying unless they dark brown gravelly loam about 11 inches thick. The upper are protected by a plant cover or adequate water bars, or 8 inches of the subsoil is dark brown gravelly clay loam. both. Cutbanks occasionally slump when the soil is The lower 41 inches is dark brown clay. The substratum to saturated. a depth of 73 inches is strong brown clay loam. The depth Constructing logging roads on the steeper slopes can to bedrock is 60 inches or more. In some areas the result in a high risk of erosion. Building the roads at surface layer is stony or cobbly. midslope requires extensive cutting and filling and removes Included in this unit are small areas of Bybee and land from production. Material that is discarded when the Pinehurst soils on concave slopes and on the less sloping roads are built can damage vegetation and is a potential parts of the landscape, Woodseye and Farva soils and source of sedimentation. If the material becomes saturated, Rock outcrop on ridges and convex slopes, and soils that avalanches of debris can occur. End hauling of the waste are similar to the Tatouche soil but have bedrock within a material minimizes damage to the vegetation downslope depth of 60 inches. Also included are and reduces the risk of sedimentation. Skid trails and unsurfaced roads may be impassable during rainy periods. Logging roads Typically, the surface layer is very dark brown clay loam require suitable surfacing for year-round use. about 10 inches thick. The upper 18 inches of the subsoil is A high temperature in the surface layer and an dark reddish brown and dark reddish gray clay. The lower insufficient moisture supply in summer increase the 22 inches is dark brown clay. The substratum is dark seedling mortality rate. To compensate for the expected yellowish brown gravelly clay loam about 10 inches thick. high mortality rate, the larger seedlings or a greater number The depth to bedrock is 60 inches or more. In some areas of seedlings should be planted. When the timber is the surface layer is gravelly or cobbly. harvested, leaving some of the larger trees unharvested Included in this unit are small areas of Coker, Freezener, provides shade for seedlings. The seedling mortality rate and Geppert soils; very poorly drained, organic soils; and also can be reduced by providing artificial shade for soils that are similar to the Terrabella soil but have bedrock seedlings. Reforestation can be accomplished by planting within a depth of 60 inches. Also included are small areas of Douglas fir and ponderosa pine seedlings. Terrabella soils that have slopes of more than 3 percent. Severe frost can damage or kill seedlings. Proper timber Included areas make up about 15 percent of the total harvesting methods can reduce the effect of frost on acreage. regeneration. Permeability is slow in the Terrabella soil. Available water Undesirable plants limit natural or artificial capacity is about 11 inches. The effective rooting depth is reforestation unless intensive site preparation and limited by the water table, which is 0.5 foot above to 1.0 foot maintenance measures are applied. Mulching around below the surface from December through May. Runoff is seedlings helps to maintain the moisture supply in ponded, and the hazard of water erosion is slight. This soil is summer and minimizes competition from undesirable subject to rare flooding. plants. This unit is used for hay and pasture (fig. 14) and for The main limitations affecting livestock grazing are wildlife habitat. This unit is suited to hay and pasture. The erosion, compaction, and the slope. The native vegetation main limitations are the seasonal wetness, compaction, the suitable for grazing includes western fescue, mountain high content of clay, and a slow rate of water intake. The brome, tall trisetum, and Alaska oniongrass. If the wetness limits the choice of suitable forage plants and the understory is overgrazed, the proportion of preferred forage period of cutting or grazing and increases the risk of plants decreases and the proportion of less preferred forage winterkill. plants increases. If the pasture is overgrazed, the proportion of preferred A planned grazing system that includes timely deferment forage plants decreases and the proportion of less of grazing, rotation grazing, and proper livestock distribution preferred forage plants increases. The grazing system helps to prevent overgrazing of the understory and damage should maintain the desired balance of species in the plant to the soil. Grazing should be delayed until the more community. Proper stocking rates, pasture rotation, and desirable forage plants have achieved enough growth to restricted grazing during wet periods help to keep pastures withstand grazing pressure and the soil is firm enough to in good condition and protect the soil from erosion. Grazing withstand trampling by livestock. when the soil is wet results in compaction of the surface Thinning, logging, and fire reduce the density of the layer, poor tilth, and excessive runoff. Periodic mowing and overstory canopy and increase the production of clipping help to maintain uniform plant growth, discourage understory vegetation. Areas that support a large amount selective grazing, and reduce the extent of clumpy growth. of competing vegetation can be improved by prescribed Tufted hairgrass is the native plant preferred for burning or by chemical or mechanical treatment. Seeding livestock grazing; however, this unit can be renovated disturbed areas to suitable plants increases forage and forage production increased by seeding other production and reduces the risk of erosion. suitable grasses. The plants selected for seeding should The vegetative site is Mixed Fir-Serviceberry Forest. be those that are tolerant of wetness. Sprinkler irrigation is the best method of applying water. 192A-Terrabella clay loam, 0 to 3 percent slopes. Border and contour flood irrigation systems also are This very deep, poorly drained soil is in basins. It formed in suitable. Because of the slow rate of water intake and the alluvium derived dominantly from andesite, tuff, and slow permeability, water applications should be regulated breccia. Elevation is 1,500 to 3,500 feet. The mean annual so that the water does not stand on the surface and precipitation is 25 to 45 inches, the mean annual damage the crop. Land leveling helps to ensure a uniform temperature is 45 to 52 degrees F, and the average application of water. Fertilizer is needed to ensure the frost-free period is 100 to 150 days. The native vegetation optimum growth of grasses and is mainly grasses, sedges, and forbs. Figure 14.-Livestock grazing in an area of Terrabella clay loam, 0 to 3 percent slopes. Freezener-Geppert complex, 12 to 35 percent south slopes, is in the background.

legumes. Grasses respond to nitrogen, and legumes surface layer is dark grayish brown and brown sandy loam respond to sulfur and phosphorus. about 10 inches thick. The subsoil is yellowish brown and The vegetative site is Wet Meadow. very pale brown sandy loam about 39 inches thick. The substratum to a depth of 60 inches is very pale brown sandy 193G-Tethrick sandy loam, 35 to 75 percent north loam. The depth to bedrock is 60 inches or more. slopes. This very deep, well drained soil is on hillslopes. It Included in this unit are small areas of Dubakella, formed in colluvium derived from granitic rock. Elevation is Goolaway, and Musty soils; Rock outcrop; Atring and Kanid 1,200 to 4,000 feet. The mean annual precipitation is 40 to soils on the more sloping parts of the landscape; and 50 inches, the mean annual temperature is 45 to 52 Wolfpeak soils on the less sloping parts of the landscape degrees F, and the average frost-free period is 100 to 160 and on concave slopes. Also included are small areas of days. The native vegetation is mainly conifers and Siskiyou soils on ridges, soils that are similar to the Tethrick hardwoods and an understory of grasses, shrubs, and soil but have bedrock at a depth of 40 to 60 inches, and forbs. Tethrick soils that have slopes of less than 35 or more than Typically, the surface is covered with a layer of 75 percent. Included areas needles, leaves, and twigs about 1 inch thick. The make up about 20 percent of the total acreage. the material becomes saturated, avalanches of debris can Permeability is moderate in the Tethrick soil. Available occur. End hauling of the waste material minimizes damage water capacity is about 6 inches. The effective rooting depth to the vegetation downslope and reduces the risk of is 60 inches or more. Runoff is rapid, and the hazard of sedimentation. Skid trails and unsurfaced roads may be water erosion is high. impassable during rainy periods. Logging roads require This unit is used for timber production and wildlife suitable surfacing for year-round use. habitat. It is suited to the production of Douglas fir. Other Undesirable plants limit natural or artificial reforestation species that grow on this unit include incense cedar, sugar unless intensive site preparation and maintenance pine, and Pacific madrone. The understory vegetation measures are applied. Reforestation can be accomplished includes golden chinkapin, cascade Oregongrape, and by planting Douglas fir seedlings. Mulching around deerfoot vanillaleaf. seedlings helps to maintain the moisture supply in On the basis of a 100-year site curve, the mean site summer and minimizes competition from undesirable index for Douglas fir is 125. The yield at culmination of the plants. mean annual increment is 7,320 cubic feet per acre in a A high temperature in the surface layer during summer fully stocked, even-aged stand of trees at 60 years and arid the low available water capacity increase the seedling 58,200 board feet per acre (Scribner rule) at 120 years. On mortality rate. To compensate for the expected high the basis of a 50-year curve, the mean site index is 90. mortality rate, the larger seedlings or a greater number of The main limitations affecting timber production are the seedlings should be planted. When the timber is harvested, slope, erosion, compaction, plant competition, and seedling leaving some of the larger trees unharvested provides mortality. When timber is harvested, management that shade for seedlings. minimizes the risk of erosion is essential. Wheeled and Increased erosion, loss of plant nutrients, and water tracked logging equipment can be used in the less sloping repellency are likely to result from fires of moderate areas, but cable yarding generally is safer and results in intensity. less surface disturbance. Using standard wheeled and The vegetative site is Douglas Fir-Chinkapin Forest. tracked equipment when the soil is moist causes rutting and compaction. Puddling can occur when the soil is wet. Using 194G-Tethrick sandy loam, 35 to 75 percent south low-pressure ground equipment causes less damage to the slopes. This very deep, well drained soil is on hillslopes. It soil and helps to maintain productivity. Compaction can be formed in colluvium derived from granitic rock. Elevation is minimized by using suitable methods of harvesting, laying 1,200 to 4,000 feet. The mean annual precipitation is 40 to out skid trails in advance, and harvesting timber when the 50 inches, the mean annual temperature is 45 to 52 soil is least susceptible to compaction. Ripping skid trails degrees F, and the average frost-free period is 100 to 160 and landings when the soil is dry can improve the growth of days. The native vegetation is mainly conifers and plants. hardwoods and an understory of grasses, shrubs, and Properly designed road drainage systems that include forbs. carefully located culverts help to control erosion. Areas that Typically, the surface is covered with a layer of needles, have been cut and filled are easily eroded unless they are leaves, and twigs about 1 inch thick. The surface layer is treated. Seeding, mulching, and benching these areas help dark grayish brown and brown sandy loam about 10 inches to control erosion. Steep yarding paths, skid trails, and thick. The subsoil is yellowish brown and very pale brown firebreaks are subject to rilling and gullying unless they are sandy loam about 39 inches thick. The substratum to a protected by a plant cover or adequate water bars, or both. depth of 60 inches is very pale brown sandy loam. The Cutbanks occasionally slump when the soil is saturated. depth to bedrock is 60 inches or more. This unit is subject to slumping, especially in areas Included in this unit are small areas of Dubakella, adjacent to drainageways. Road failure and landslides are Goolaway, and Musty soils; Rock outcrop; Atring and Kanid likely to occur after road construction and clearcutting. soils on the more sloping parts of the landscape; and Constructing logging roads on the steeper slopes can Wolfpeak soils on the less sloping parts of the landscape result in a high risk of erosion. Building the roads at and on concave slopes. Also included are small areas of midslope requires extensive cutting and filling and removes Siskiyou soils on ridges, soils that are similar to the Tethrick land from production. Material that is discarded when the soil but have bedrock at a depth of 40 to 60 inches, and roads are built can damage vegetation and is a potential Tethrick soils that have slopes of less than 35 or more than source of sedimentation. If 75 percent. Included areas make up about 20 percent of the total acreage. Permeability is moderate in the Tethrick soil. Available water capacity is about 6 inches. The effective rooting depth is 60 inches or more. Runoff is rapid, and the risk of sedimentation. Skid trails and unsurfaced roads may hazard of water erosion is high. be impassable during rainy periods. Logging roads require This unit is used for timber production and wildlife suitable surfacing for year-round use. habitat. It is suited to the production of Douglas fir. Other A high temperature in the surface layer during summer species that grow on this unit include ponderosa pine, and the low available water capacity increase the seedling sugar pine, and California black oak. The understory mortality rate. To compensate for the expected high vegetation includes canyon live oak, deerbrush, and mortality rate, the larger seedlings or a greater number of western fescue. seedlings should be planted. When the timber is harvested, On the basis of a 100-year site curve, the mean site leaving some of the larger trees unharvested provides index for Douglas fir is 115. The yield at culmination of the shade for seedlings. The seedling mortality rate also can be mean annual increment is 6,360 cubic feet per acre in a reduced by providing artificial shade for seedlings. fully stocked, even-aged stand of trees at 60 years and Reforestation can be accomplished by planting Douglas fir 50,700 board feet per acre (Scribner rule) at 130 years. On and ponderosa pine seedlings. the basis of a 50-year curve, the mean site index is 85. Undesirable plants limit natural or artificial The main limitations affecting timber production are the reforestation unless intensive site preparation and slope, erosion, compaction, seedling mortality, and plant maintenance measures are applied. Mulching around competition. When timber is harvested, management that seedlings helps to maintain the moisture supply in minimizes the risk of erosion is essential. Wheeled and summer and minimizes competition from undesirable tracked logging equipment can be used in the less sloping plants. areas, but cable yarding generally is safer and results in Increased erosion, loss of plant nutrients, and water less surface disturbance. Using standard wheeled and repellency are likely to result from fires of moderate tracked equipment when the soil is moist causes rutting and intensity. compaction. Puddling can occur when the soil is wet. Using The vegetative site is Douglas Fir-Black Oak Forest. low-pressure ground equipment causes less damage to the soil and helps to maintain productivity. Compaction can be 195E-Vannoy silt loam, 12 to 35 percent north slopes. minimized by using suitable methods of harvesting, laying This moderately deep, well drained soil is on hillslopes. It out skid trails in ,advance, and harvesting timber when the formed in colluvium derived dominantly from metamorphic soil is least susceptible to compaction. Ripping skid trails rock. Elevation is 1,000 to 4,000 feet. The mean annual and landings when the soil is dry can improve the growth of precipitation is 20 to 40 inches, the mean annual plants. temperature is 46 to 54 degrees F, and the average Properly designed road drainage systems that include frost-free period is 100 to 160 days. The native vegetation is carefully located culverts help to control erosion. Areas that mainly conifers and hardwoods and an understory of have been cut and filled are easily eroded unless they are grasses, shrubs, and forbs. treated. Seeding, mulching, and benching these areas help Typically, the surface is covered with a layer of needles, to control erosion. Steep yarding paths, skid trails, and leaves, and twigs about 3/4 inch thick. The surface layer is firebreaks are subject to rilling and gullying unless they are dark brown silt loam about 4 inches thick. The next layer is protected by a plant cover or adequate water bars, or both. reddish brown silt loam about 7 inches thick. The subsoil is Cutbanks occasionally slump when the soil is saturated. yellowish red clay loam about 27 inches thick. Weathered This unit is subject to slumping, especially in areas bedrock is at a depth of about 38 inches. The depth to adjacent to drainageways. Road failure and landslides are bedrock ranges from 20 to 40 inches. In some areas the likely to occur after road construction and clearcutting. surface layer is gravelly or very gravelly. Constructing logging roads on the steeper slopes can Included in this unit are small areas of Rock outcrop and result in a high risk of erosion. Building the roads at McMullin soils on ridges and convex slopes; Selmac soils on midslope requires extensive cutting and filling and removes concave slopes; Caris and Offenbacher soils on the more land from production. Material that is discarded when the sloping parts of the landscape; and Manita, Ruch, and roads are built can damage vegetation and is a potential Voorhies soils. Also included are small areas of soils that source of sedimentation. If the material becomes saturated, are similar to the Vannoy soil but have bedrock at a depth of avalanches of debris can occur. End hauling of the waste more than 40 inches, poorly drained soils near material minimizes damage to the vegetation downslope drainageways, and Vannoy soils that have slopes of less and reduces the than 12 or more than 35 percent. Included areas make up about 20 percent of the total acreage. Permeability is moderately slow in the Vannoy soil. Available water capacity is about 5 inches. The effective expected high mortality rate, the larger seedlings or a rooting depth is 20 to 40 inches. Runoff is medium, and the greater number of seedlings should be planted. When the hazard of water erosion is moderate. timber is harvested, leaving some of the larger trees This unit is used mainly for timber production. It also is unharvested provides shade for seedlings. used for pasture and homesite development. The main limitations in the areas used as pasture are the This unit is suited to the production of Douglas fir. Other slope, erosion, and droughtiness. Seedbeds should be species that grow on this unit include incense cedar, prepared on the contour or across the slope where practical. ponderosa pine, and Pacific madrone. The understory Proper stocking rates, pasture rotation, and restricted vegetation includes creambush oceanspray, common grazing during wet periods help to keep pastures in good snowberry, and tall Oregongrape. condition and protect the soil from erosion. Grazing when On the basis of a 100-year site curve, the mean site the soil is wet results in compaction of the surface layer, index for Douglas fir is 110. The yield at culmination of the poor tilth, and excessive runoff. Periodic mowing and mean annual increment is 5,880 cubic feet per acre in a clipping help to maintain uniform plant growth, discourage fully stocked, even-aged stand of trees at 60 years and selective grazing, and reduce the extent of clumpy growth. 48,300 board feet per acre (Scribner rule) at 140 years. On Fertilizer is needed to ensure the optimum growth of grasses the basis of a 50-year curve, the mean site index is 80. and legumes. Grasses respond to nitrogen, and legumes The main limitations affecting timber production are respond to sulfur and phosphorus. erosion, compaction, plant competition, and seedling Because of low rainfall in summer, forage production mortality. Also, the bedrock restricts root growth. As a would be increased if this unit were irrigated. Irrigation is result, windthrow is a hazard. difficult, however, because of a limited water supply and the Wheeled and tracked logging equipment can be used in slope. the less sloping areas, but cable yarding generally is safer The main limitations affecting homesite development are in the more sloping areas and results in less surface the depth to bedrock, the slope, the moderately slow disturbance. Using standard wheeled and tracked permeability, and low strength. The moderately slow equipment when the soil is moist causes rutting and permeability is a limitation on sites for septic tank compaction. Puddling can occur when the soil is wet. Using absorption fields. It can be overcome by increasing the size low-pressure ground equipment causes less damage to the of the absorption field. Because of the slope, the absorption soil and helps to maintain productivity. Compaction can be lines should be installed on the contour. Areas where the minimized by using suitable methods of harvesting, laying soil is deeper and less sloping may be suited to septic tank out skid trails in advance, and harvesting timber when the absorption fields. Onsite investigation is needed to locate soil is least susceptible to compaction. Ripping skid trails such areas. and landings when the soil is dry can improve the growth of The slope limits the use of some areas for building site plants. development. Cuts needed to provide essentially level Properly designed road drainage systems that include building sites can expose bedrock. Properly designing carefully located culverts help to control erosion. Seeding, buildings and roads helps to offset the limited ability of the mulching, and benching areas that have been cut and filled soil to support a load. also help to control erosion. Steep yarding paths, skid trails, Erosion is a hazard on the steeper slopes. Only the and firebreaks are subject to rilling and gullying unless they part of the site that is used for construction should be are protected by a plant cover or adequate water bars, or disturbed. Revegetating as soon as possible helps to both. Skid trails and unsurfaced roads may be impassable control erosion in disturbed areas around construction during rainy periods. Logging roads require suitable sites. Topsoil can be stockpiled and used to reclaim areas surfacing for year-round use. disturbed during construction. Because of a low amount of Undesirable plants limit natural or artificial reforestation rainfall in summer, irrigation is needed in areas that unless intensive site preparation and maintenance support lawn grasses, shrubs, vines, shade trees, or measures are applied. Reforestation can be accomplished ornamental trees. by planting Douglas fir and ponderosa pine seedlings. The vegetative site is Douglas Fir Forest. Mulching around seedlings helps to maintain the moisture supply in summer and minimizes competition from 195F-Vannoy silt loam, 35 to 55 percent north undesirable plants. slopes. This moderately deep, well drained soil is on A high temperature in the surface layer during summer hillslopes. It formed in colluvium derived from metamorphic and the low available water capacity increase the seedling rock. Elevation is 1,000 to 4,000 feet. The mean annual mortality rate. To compensate for the precipitation is 20 to 40 inches, the mean annual temperature is 46 to 54 degrees F, and the average frost-free period is 100 to 160 days. The native least susceptible to compaction. When the soil is dry, vegetation is mainly conifers and hardwoods and an ripping skid trails and landings improves the growth of understory of grasses, shrubs, and forbs. plants. Typically, the surface is covered with a layer of needles, Properly designed road drainage systems that include leaves, and twigs about 3/a inch thick. The surface layer is carefully located culverts help to control erosion. Seeding, dark brown silt loam about 4 inches thick. The next layer is mulching, and benching areas that have been cut and filled reddish brown silt loam about 7 inches thick. The subsoil is also help to control erosion. Steep yarding paths, skid trails, yellowish red clay loam about 27 inches thick. Weathered and firebreaks are subject to rilling and gullying unless they bedrock is at a depth of about 38 inches. The depth to are protected by a plant cover or adequate water bars, or bedrock ranges from 20 to 40 inches. In some areas the both. Cutbanks occasionally slump when the soil is surface layer is gravelly or very gravelly loam. saturated. Included in this unit are small areas of Voorhies soils, Constructing logging roads on the steeper slopes can Caris and Offenbacher soils on the more sloping parts of the result in a high risk of erosion. Material that is discarded landscape, McMullin soils and Rock outcrop on ridges and when the roads are built can damage vegetation and is a convex slopes, Manita soils on the less sloping parts of the potential source of sedimentation. If the material becomes landscape and on concave slopes, and soils that are similar saturated, avalanches of debris can occur. End hauling of to the Vannoy soil but have bedrock at a depth of more than the waste material minimizes damage to the vegetation 40 inches. Also included are small areas of Vannoy soils downslope and reduces the risk of sedimentation. Skid trails that have slopes of less than 35 or more than 55 percent. and unsurfaced roads may be impassable during rainy Included areas make up about 20 percent of the total periods. Logging roads require suitable surfacing for acreage. year-round use. Permeability is moderately slow in the Vannoy soil. Undesirable plants limit natural or artificial reforestation Available water capacity is about 5 inches. The effective unless intensive site preparation and maintenance rooting depth is 20 to 40 inches. Runoff is rapid, and the measures are applied. Reforestation can be accomplished hazard of water erosion is high. by planting Douglas fir and ponderosa pine seedlings. This unit is used for timber production and wildlife Mulching around seedlings helps to maintain the moisture habitat. It is suited to the production of Douglas fir. Other supply in summer and minimizes competition from species that grow on this unit include incense cedar, undesirable plants. ponderosa pine, and Pacific madrone. The understory A high temperature in the surface layer and an vegetation includes creambush oceanspray, common insufficient moisture supply in summer increase the snowberry, and tall Oregongrape. seedling mortality rate. To compensate for the expected On the basis of a 100-year site curve, the mean site high mortality rate, the larger seedlings or a greater number index for Douglas fir is 110. The yield at culmination of the of seedlings should be planted. When the timber is mean annual increment is 5,880 cubic feet per acre in a harvested, leaving some of the larger trees unharvested fully stocked, even-aged stand of trees at 60 years and provides shade for seedlings. 48,300 board feet per acre (Scribner rule) at 140 years. On The vegetative site is Douglas Fir Forest. the basis of a 50-year curve, the mean site index is 80. The main limitations affecting timber production are the 196E-Vannoy silt loam, 12 to 35 percent south slope, erosion, compaction, plant competition, and slopes. This moderately deep, well drained soil is on seedling mortality. Also, the bedrock restricts root growth. hillslopes. It formed in colluvium derived dominantly from As a result, windthrow is a hazard. metamorphic rock. Elevation is 1,000 to 4,000 feet. The Wheeled and tracked logging equipment can be used in mean annual precipitation is 20 to 40 inches, the mean the less sloping areas, but cable yarding generally is safer annual temperature is 46 to 54 degrees F, and the average and results in less surface disturbance. Using standard frost-free period is 100 to 160 days. The native vegetation is wheeled and tracked equipment when the soil is moist mainly conifers and hardwoods and an understory of causes rutting and compaction. Puddling can occur when grasses, shrubs, and forbs. the soil is wet. Using low-pressure ground equipment Typically, the surface is covered with a layer of needles, causes less damage to the soil and helps to maintain leaves, and twigs about 3/a inch thick. The surface layer is productivity. Compaction can be minimized by using dark brown silt loam about 4 inches thick. The next layer is suitable methods of harvesting, laying out skid trails in reddish brown silt loam about 7 inches thick. The subsoil is advance, and harvesting timber when the soil is yellowish red clay loam about 27 inches thick. Weathered bedrock is at a depth of about 38 inches. The depth to bedrock ranges from 20 to 40 inches. In some areas the surface layer is Properly designed road drainage systems that include gravelly or very gravelly. carefully located culverts help to control erosion. Seeding, Included in this unit are small areas of Rock outcrop and mulching, and benching areas that have been cut and filled McMullin soils on ridges and convex slopes; Selmac soils on also help to control erosion. Steep yarding paths, skid trails, concave slopes; Caris and Offenbacher soils on the more and firebreaks are subject to rilling and gullying unless they sloping parts of the landscape; and Manita, Ruch, and are protected by a plant cover or adequate water bars, or Voorhies soils. Also included are small. areas of soils that both. Skid trails and unsurfaced roads may be impassable are similar to the Vannoy soil but have bedrock at a depth of during rainy periods. Logging roads require suitable more than 40 inches, poorly drained soils near surfacing for year-round use. drainageways, and Vannoy soils that have slopes of less A high temperature in the surface layer during summer than 12 or more than 35 percent. Included areas make up and the low available water capacity increase the seedling about 20 percent of the total acreage. mortality rate. To compensate for the expected high Permeability is moderately slow in the Vannoy soil. mortality rate, the larger seedlings or a greater number of Available water capacity is about 5 inches. The effective seedlings should be planted. When the timber is harvested, rooting depth is 20 to 40 inches. Runoff is medium, and the leaving some of the larger trees unharvested provides hazard of water erosion is moderate. shade for seedlings. Reforestation can be accomplished by This unit is used mainly for timber production. It also is planting Douglas fir and ponderosa pine seedlings. used for pasture and homesite development. Undesirable plants limit natural or artificial This unit is suited to the production of Douglas fir and reforestation unless intensive site preparation and ponderosa pine. Other species that grow on this unit maintenance measures are applied. Mulching around include incense cedar, California black oak, and Pacific seedlings helps to maintain the moisture supply in madrone. The understory vegetation includes Pacific summer and minimizes competition from undesirable serviceberry, tall Oregongrape, and California fescue. plants. On the basis of a 100-year site curve, the mean site The main limitations in the areas used as pasture are the index for Douglas fir is 105. The yield at culmination of the slope, erosion, and droughtiness. Seedbeds should be mean annual increment is 5,460 cubic feet per acre in a prepared on the contour or across the slope where practical. fully stocked, even-aged stand of trees at 60 years and Proper stocking rates, pasture rotation, and restricted 45,600 board feet per acre (Scribner rule) at 150 years. On grazing during wet periods help to keep pastures in good the basis of a 50-year curve, the mean site index is 75. condition and protect the soil from erosion. Grazing when On the basis of a 100-year site curve, the mean site the soil is wet results in compaction of the surface layer, index for ponderosa pine is 90. The yield at culmination of poor tilth, and excessive runoff. Periodic mowing and the mean annual increment is 3,400 cubic feet per acre in a clipping help to maintain uniform plant growth, discourage fully stocked, even-aged stand of trees at 40 years and selective grazing, and reduce the extent of clumpy growth. 37,960 board feet per acre (Scribner rule) at 130 years. Fertilizer is needed to ensure the optimum growth of grasses The main limitations affecting timber production are and legumes. Grasses respond to nitrogen, and legumes erosion, compaction, seedling mortality, and plant respond to sulfur and phosphorus. competition. Wheeled and tracked logging equipment can Because of low rainfall in summer, forage production be used in the less sloping areas, but cable yarding would be increased if this unit were irrigated. Irrigation is generally is safer in the more sloping areas and results in difficult, however, because of a limited water supply and less surface disturbance. Using standard wheeled and the slope. tracked equipment when the soil is moist causes rutting and The main limitations affecting homesite development are compaction. Puddling can occur when the soil is wet. Using the 'depth to bedrock, the slope, the moderately slow low-pressure ground equipment causes less damage to the permeability, and low strength. The moderately slow soil and helps to maintain productivity. Compaction can be permeability is a limitation on sites for septic tank minimized by using suitable methods of harvesting, laying absorption fields. It can be overcome by increasing the size out skid trails in advance, and harvesting timber when the of the absorption field. Because of the slope, the absorption soil is least susceptible to compaction. Ripping skid trails lines should be installed on the contour. Areas where the and landings when the soil is dry can improve the growth of soil is deeper and less sloping may be suited to septic tank plants. absorption fields. Onsite investigation is needed to locate such areas. The slope limits the use of some areas for building site development. Cuts needed to provide essentially level metamorphic rock. Typically, the surface is covered with a building sites can expose bedrock. Properly designing layer of needles and twigs about 1 inch thick. The surface buildings and roads helps to offset the limited ability of the layer is very dark grayish brown and dark brown very soil to support a load. gravelly loam about 8 inches thick. The upper 10 inches of Erosion is a hazard on the steeper slopes. Only the the subsoil is brown very gravelly clay loam. The lower 18 part of the site that is used for construction should be inches is brown very cobbly clay loam. Weathered bedrock disturbed. Revegetating as soon as possible helps to is at a depth of about 36 inches. The depth to bedrock control erosion in disturbed areas around construction ranges from 20 to 40 inches. sites. Topsoil can be stockpiled and used to reclaim areas Permeability is moderate in the Voorhies soil. Available disturbed during construction. Because of a low amount of water capacity is about 3 inches. The effective rooting depth rainfall in summer, irrigation is needed in areas that is 20 to 40 inches. Runoff is rapid, and the hazard of water support lawn grasses, shrubs, vines, shade trees, or erosion is high. ornamental trees. This unit is used for timber production and wildlife The vegetative site is Pine-Douglas Fir-Fescue. habitat. It is suited to the production of Douglas fir and ponderosa pine. Other species that grow on this unit 197F-Vannoy-Voorhies complex, 35 to 55 percent include incense cedar, California black oak, and Pacific south slopes. This map unit is on hillslopes. Elevation is madrone. The understory vegetation includes Pacific 1,000 to 4,000 feet. The mean annual precipitation is 20 to serviceberry, tall Oregongrape, and California fescue. 40 inches, the mean annual temperature is 46 to 54 On the basis of a 100-year site curve, the mean site degrees F, and the average frost-free period is 100 to 160 index for Douglas fir is 100 on the Vannoy soil. The yield at days. The native vegetation is mainly conifers and culmination of the mean annual increment is 5,040 cubic hardwoods and an understory of grasses, shrubs, and feet per acre in a fully stocked, even-aged stand of trees at forbs. 60 years and 39,750 board feet per acre (Scribner rule) at This unit is about 60 percent Vannoy soil and 30 150 years. On the basis of a 50-year curve, the mean site percent Voorhies soil. The components of this unit occur index is 75. as areas so intricately intermingled that mapping them On the basis of a 100-year site curve, the mean site separately was not practical at the scale used. index for ponderosa pine is 90 on the Vannoy soil. The Included in this unit are small areas of McMullin soils and yield at culmination of the mean annual increment is 3,400 Rock outcrop on ridges and convex slopes, Caris and cubic feet per acre in a fully stocked, even-aged stand of Offenbacher soils on the more sloping parts of the trees at 40 years and 37,960 board feet per acre (Scribner landscape, Manita soils on the less sloping parts of the rule) at 130 years. landscape and on concave slopes, and soils that are similar On the basis of a 100-year site curve, the mean site to the Vannoy soil but have bedrock at a depth more than index for Douglas fir is 95 on the Voorhies soil. The yield at 40 inches. Also included are small areas of Vannoy and culmination of the mean annual increment is 4,620 cubic Voorhies soils that have slopes of less than 35 or more than feet per acre in a fully stocked, even-aged stand of trees at 55 percent. Included areas make up about 10 percent of the 60 years and 37,120 board feet per acre (Scribner rule) at total acreage. 160 years. On the basis of a 50-year curve, the mean site The Vannoy soil is moderately deep and well drained. It index is 65. formed in colluvium derived dominantly from metamorphic On the basis of a 100-year site curve, the mean site index rock. Typically, the surface is covered with a layer of for ponderosa pine is 75 on the Voorhies soil. The yield at needles, leaves, and twigs about 3/4 inch thick. The surface culmination of the mean annual increment is 3,100 cubic feet layer is dark brown silt loam about 4 inches thick. The next per acre in a fully stocked, even-aged stand of trees at 50 layer is reddish brown silt loam about 7 inches thick. The years and 31,680 board feet per acre (Scribner rule) at 160 subsoil is yellowish red clay loam about 27 inches thick. years. Weathered bedrock is at a depth of about 38 inches. The The main limitations affecting timber production are the depth to bedrock ranges from 20 to 40 inches. In some slope, erosion, compaction, seedling mortality, and plant areas the surface layer is gravelly or very gravelly loam. competition. Also, the bedrock restricts root growth. As a Permeability is moderately slow in the Vannoy soil. result, windthrow is a hazard. Available water capacity is about 5 inches. The effective Wheeled and tracked logging equipment can be used in rooting depth is 20 to 40 inches. Runoff is rapid, and the the less sloping areas, but cable yarding generally is safer hazard of water erosion is high. and results in less surface disturbance. If the soils are The Voorhies soil is moderately deep and well drained. excessively disturbed when timber is harvested or logging It formed in colluvium derived dominantly from roads are built, a large number of rock fragments is left on the surface. Using standard wheeled and tracked equipment when the soils are moist degrees F, and the average frost-free period is 150 to 180 causes rutting and compaction. Puddling can occur when days. The native vegetation is mainly rushes, sedges, and the soils are wet. Using low-pressure ground equipment grasses and scattered water-tolerant hardwoods. causes less damage to the soils and helps to maintain Typically, the surface layer is very dark grayish brown productivity. Compaction can be minimized by using very gravelly clay loam about 4 inches thick. The upper 5 suitable methods of harvesting, laying out skid trails in inches of the subsoil is dark brown very gravelly clay. The advance, and harvesting timber when the soils are least lower 8 inches is a hardpan. The substratum to a depth of susceptible to compaction. Ripping skid trails and landings 60 inches is light olive brown extremely gravelly coarse when the soils are dry can improve the growth of plants. sandy loam. Depth to the hardpan is 7 to 15 inches. The Properly designed road drainage systems that include depth to bedrock is 60 inches or more. In some areas the carefully located culverts help to control erosion Seeding, surface layer is very cobbly or very gravelly clay. mulching, and benching areas that have been cut and filled Included in this unit are small areas of Agate soils, soils also help to control erosion. Steep yarding paths, skid trails, that are similar to the Winlo soil but have a hardpan at a and firebreaks are subject to rilling and gullying unless they depth of more than 15 inches, and Cove and Padigan soils are protected by a plant cover or adequate water bars, or on concave slopes and near drainageways. Also included both. Cutbanks occasionally slump when the soils are are small areas of Winlo soils that have slopes of more saturated. than 3 percent. Included areas make up about 20 percent Constructing logging roads on the steeper slopes can of the total acreage. result in a high risk of erosion. Material that is discarded Permeability is slow in the Winlo soil. Available water when the roads are built can damage vegetation and is a capacity is about 1 inch. The effective rooting depth is 7 to potential source of sedimentation. If the material becomes 15 inches. Runoff is ponded, and the hazard of water saturated, avalanches of debris can occur. End hauling of erosion is slight. The water table is 0.5 foot above to 0.5 foot the waste material minimizes damage to the vegetation below the surface from December through February. downslope and reduces the risk of sedimentation. Skid trails This unit is used mainly for pasture. It also is used for and unsurfaced roads may be impassable during rainy homesite development. periods. Logging roads require suitable surfacing for The main limitations in the areas used as pasture are year-round use. wetness in winter and spring, droughtiness in summer and A high temperature in the surface layer during summer fall, depth to the hardpan, the very gravelly surface layer, and the low available water capacity increase the seedling and compaction. If the pasture is overgrazed, the proportion mortality rate. The large number of rock fragments in the of preferred forage plants decreases and the proportion of Voorhies soil also increases the seedling mortality rate. To less preferred forage plants increases. The grazing system compensate for the expected high mortality rate, the larger should maintain the desired balance of species in the plant seedlings or a greater number of seedlings should be community. Wetness limits the choice of suitable forage planted. When the timber is harvested, leaving some of the plants and the period of grazing and increases the risk of larger trees unharvested provides shade for seedlings. The winterkill. The use of ground equipment is limited by the seedling mortality rate also can be reduced by providing gravel and cobbles on the surface. artificial shade for seedlings. Reforestation can be Proper stocking rates, pasture rotation, and restricted accomplished by planting Douglas. fir and ponderosa pine grazing during wet periods help to keep pastures in good seedlings. condition and protect the soil from erosion. Grazing when Undesirable plants limit natural or artificial the soil is wet results in compaction of the surface layer, reforestation unless intensive site preparation and poor tilth, and excessive runoff. If possible, periodic mowing maintenance measures are applied. Mulching around and clipping help to maintain uniform plant growth, seedlings helps to maintain the moisture supply in discourage selective grazing, and reduce the extent of summer and minimizes competition from undesirable clumpy growth. Fertilizer is needed to ensure the optimum plants. growth of grasses and legumes. Grasses respond to The vegetative site is Pine-Douglas Fir-Fescue. nitrogen, and legumes respond to sulfur and phosphorus. This unit is limited as a site for livestock watering 198A-Winlo very gravelly clay loam, 0 to 3 percent ponds and other water impoundments because of the slopes. This somewhat poorly drained soil is on fan depth to a hardpan. terraces. It is shallow to a hardpan. It formed in alluvium derived from mixed sources. Elevation is 1,100 to 1,500 feet. The mean annual precipitation is 18 to 30 inches, the mean annual temperature is 52 to 54 In summer, irrigation is needed for maximum forage yellowish brown and strong brown clay loam. The depth to production. Sprinkler irrigation is the best method of bedrock is 60 inches or more. In some areas the surface applying water. Contour flood irrigation also is suitable. layer is clay loam. Because of the slow permeability and the depth to a Included in this unit are small areas of Clawson soils hardpan, water applications should be regulated so that the near drainageways and on concave slopes, Josephine and water does not stand on the surface and damage the crop. Pollard soils, and soils that are similar to the Wolfpeak soil Land leveling is not practical because of the depth to a but have bedrock within a depth of 60 inches. Also included hardpan. are small areas of Wolfpeak soils that have slopes of more Tile drainage systems are not practical because of the than 12 percent. Included areas make up about 15 percent depth to a hardpan. Open ditches may be used to reduce of the total acreage. surface wetness. Permeability is moderately slow in the Wolfpeak soil. This unit is poorly suited to homesite development. Available water capacity is about 8 inches. The effective The main limitations are the wetness, depth to the rooting depth is 60 inches or more. Runoff is slow, and the hardpan, and the very gravelly surface layer. hazard of water erosion is moderate. This unit is poorly suited to standard systems of waste This unit is used mainly for timber production or wildlife disposal because of the wetness and the depth to a habitat. It also is used for hay and pasture and for hardpan. Alternative waste disposal systems may function homesite development. properly on this unit. Suitable included soils are in some This unit is suited to irrigation crops. It is limited mainly by areas of the unit. Onsite investigation is needed to locate the moderately slow permeability and the hazard of erosion. such soils. In summer, irrigation is needed for the maximum production Because the seasonal high water table is perched of most crops. Sprinkler irrigation is the best method of above the hardpan, a drainage system is needed on sites applying water. This method permits an even, controlled for buildings with basements and crawl spaces. A drainage application of water, helps to prevent excessive runoff, and system also is needed if roads or building foundations are minimizes the risk of erosion. Border and contour flood constructed. Excess water can be removed by suitably irrigation systems also are suitable. For the efficient designed drainage ditches. application and removal of surface irrigation water, land Cuts needed to provide essentially level building sites leveling is needed. To prevent overirrigation and excessive can expose the hardpan. Establishing plants is difficult in erosion, applications of irrigation water should be adjusted areas where the hardpan has been exposed. Mulching and to the available water capacity, the rate of water intake, and applying fertilizer help to establish plants in cut areas. the needs of the crop. The use of pipe, ditch lining, or drop Gravel and cobbles should be removed from disturbed structures in irrigation ditches reduces water loss and the areas, particularly areas used for lawns. In many areas it hazard of erosion. may be necessary to haul in topsoil for lawns and gardens. Returning all crop residue to the soil and using a Because of a low amount of rainfall in summer, irrigation is cropping system that includes grasses, legumes, or needed in areas that support lawn grasses, shrubs, vines, grass-legume mixtures help to maintain fertility and tilth. shade trees, or ornamental trees. Leaving crop residue on or near the surface helps to The vegetative site is Poorly Drained Bottom. conserve moisture and control erosion. A tillage pan forms easily if the soil is tilled when wet. 199C-Wolfpeak sandy loam, 3 to 12 percent slopes. Chiseling or subsoiling breaks up the pan. Surface crusting This very deep, well drained soil is on alluvial fans. It and compaction can be minimized by returning crop residue formed in residuum and alluvium derived dominantly from to the soil. granitic rock. Elevation is 1,200 to 4,000 feet. The mean Seedbeds should be prepared on the contour or across annual precipitation is 40 to 50 inches, the mean annual the slope where practical. Proper stocking rates, pasture temperature is 45 to 52 degrees F, and the average rotation, and restricted grazing during wet periods help to frost-free period is 100 to 160 days. The native vegetation keep pastures in good condition and protect the soil from is mainly conifers and hardwoods and an understory of erosion. Grazing when the soil is wet results in compaction grasses, shrubs, and forbs. of the surface layer, poor tilth, and excessive runoff. Periodic Typically, the surface is covered with a layer of mowing and clipping help to maintain uniform plant growth, needles, leaves, and twigs about 1/2 inch thick. The discourage selective grazing, and reduce the extent of surface layer is dark brown sandy loam about 4 inches clumpy growth. Fertilizer is needed to ensure the optimum thick. The next layer is brown sandy loam about 7 inches growth of grasses and legumes. Grasses respond to thick. The subsoil to a depth of 60 inches is nitrogen, and legumes respond to sulfur and phosphorus. This unit is well suited to homesite development. The reforestation unless intensive site preparation and main limitations are the moderately slow permeability and maintenance measures are applied. Reforestation can be the shrink-swell potential. The moderately slow permeability accomplished by planting Douglas fir seedlings. Mulching is a limitation on sites for septic tank absorption fields. It can around seedlings helps to maintain the moisture supply in be overcome by increasing the size of the absorption field. summer and minimizes competition from undesirable If buildings are constructed on this unit, properly plants. designing foundations and footings, diverting runoff away A high temperature in the surface layer and an from the buildings, and backfilling with material that has a insufficient moisture supply in summer increase the low shrink -swell potential help to prevent the structural seedling mortality rate. To compensate for the expected damage caused by shrinking and swelling. Properly high mortality rate, the larger seedlings or a greater number designing buildings and roads helps to offset the limited of seedlings should be planted. When the timber is ability of the soil to support a load. harvested, leaving some of the larger trees unharvested Revegetating as soon as possible helps to control provides shade for seedlings. erosion in disturbed areas around construction sites. Increased erosion, loss of plant nutrients, and water Topsoil can be stockpiled and used to reclaim areas repellency are likely to result from fires of moderate disturbed during construction. Because of a low amount of intensity. rainfall in summer, irrigation is needed in areas that support The vegetative site is Douglas Fir-Chinkapin Forest. lawn grasses, shrubs, vines, shade trees, or ornamental trees. 200E-Wolfpeak sandy loam, 12 to 35 percent north This unit is suited to the production of Douglas fir. Other slopes. This very deep, well drained soil is on hillslopes. It species that grow on this unit include ponderosa pine, formed in colluvium and residuum derived from granitic incense cedar, and sugar pine. The understory vegetation rock. Elevation is 1,200 to 4,000 feet. The mean annual includes golden chinkapin, cascade Oregongrape, and precipitation is 40 to 50 inches, the mean annual deerfoot vanillaleaf. temperature is 45 to 52 degrees F, and the average On the basis of a 100-year site curve, the mean site frost-free period is 100 to 160 days. The native vegetation is index for Douglas fir is 130. The yield at culmination of the mainly conifers and hardwoods and an understory of mean annual increment is 7,740 cubic feet per acre in a grasses, shrubs, and forbs. fully stocked, even-aged stand of trees at 60 years and Typically, the surface is covered with a layer of needles, 58,520 board feet per acre (Scribner rule) at 110 years. On leaves, and twigs about 1/2 inch thick. The surface layer is the basis of a 50-year curve, the mean site index is 95. dark brown sandy loam about 4 inches thick. The next layer The main limitations affecting timber production are is brown sandy loam about 7 inches thick. The subsoil to a compaction, erosion, plant competition, and seedling depth of 60 inches is yellowish brown and strong brown clay mortality. When timber is harvested, management that loam. The depth to bedrock is 60 inches or more. In some minimizes the risk of erosion is essential. Conventional areas the surface layer is clay loam. methods of harvesting timber generally are suitable, but the Included in this unit are small areas of Josephine, soil may be compacted if it is moist when heavy equipment Goolaway, Musty, and Pollard soils; Tethrick soils on the is used. Puddling can occur when the soil is wet. Using more sloping parts of the landscape; and Siskiyou soils on low-pressure ground equipment causes less damage to the ridges and convex slopes. Also included are small areas of soil and helps to maintain productivity. Compaction can be poorly drained soils near drainageways and on concave minimized by using suitable methods of harvesting, laying slopes, soils that are similar to the Wolfpeak soil but have out skid trails in advance, and harvesting timber when the bedrock within a depth of 60 inches, and Wolfpeak soils that soil is least susceptible to compaction. Ripping skid trails have slopes of less than 12 or more than 35 percent. and landings when the soil is dry can improve the growth of Included areas make up about 20 percent of the total plants. acreage. Erosion can be controlled by carefully planning the Permeability is moderately slow in the Wolfpeak soil. construction and maintenance of logging roads, skid trails, Available water capacity is about 8 inches. The effective and landings. Seeding, mulching, and benching areas that rooting depth is 60 inches or more. Runoff is medium, and have been cut and filled also help to control erosion. Skid the hazard of water erosion is moderate or high. trails and unsurfaced roads may be impassable during This unit is used for timber production and wildlife rainy periods. Logging roads require suitable surfacing for habitat. It is suited to the production of Douglas fir. Other year-round use. species that grow on this unit include incense cedar, sugar Undesirable plants limit natural or artificial pine, and Pacific madrone. The understory vegetation includes golden chinkapin, cascade timber is harvested, leaving some of the larger trees Oregongrape, and deerfoot vanillaleaf. unharvested provides shade for seedlings. On the basis of a 100-year site curve, the mean site Increased erosion, loss of plant nutrients, and water index for Douglas fir is 130. The yield at culmination of the repellency are likely to result from fires of moderate mean annual increment is 7,740 cubic feet per acre in a intensity. fully stocked, even-aged stand of trees at 60 years and The vegetative site is Douglas Fir-Chinkapin Forest. 58,520 board feet per acre (Scribner rule) at 110 years. On the basis of a 50-year curve, the mean site index is 95. 201E-Wolfpeak sandy loam, 12 to 35 percent south The main limitations affecting timber production are slopes. This very deep, well drained soil is on hillslopes. It erosion, compaction, plant competition, and seedling formed in colluvium and residuum derived from granitic mortality. When timber is harvested, management that rock. Elevation is 1,200 to 4,000 feet. The mean annual minimizes the risk of erosion is essential. Wheeled and precipitation is 40 to 50 inches, the mean annual tracked logging equipment can be used in the less sloping temperature is 45 to 52 degrees F, and the average areas, but cable yarding generally is safer in the more frost-free period is 100 to 160 days. The native vegetation is sloping areas and results in less surface disturbance. Using mainly conifers and hardwoods and an understory of standard wheeled and tracked equipment when the soil is grasses, shrubs, and forbs. moist causes rutting and compaction. Puddling can occur Typically, the surface is covered with a layer of needles, when the soil is wet. Using low-pressure ground equipment leaves, and twigs about 1/2 inch thick. The surface layer is causes less damage to the soil and helps to maintain dark brown sandy loam about 4 inches thick. The next layer productivity. Compaction can be minimized by using suitable is brown sandy loam about 7 inches thick. The subsoil to a methods of harvesting, laying out skid trails in advance, and depth of 60 inches is yellowish brown and strong brown harvesting timber when the soil is least susceptible to clay loam. The depth to bedrock is 60 inches or more. In compaction. Ripping skid trails and landings when the soil is some areas the surface layer is clay loam. dry can improve the growth of plants. Included in this unit are small areas of Josephine, Properly designed road drainage systems that include Goolaway, Musty, and Pollard soils; Tethrick soils on the carefully located culverts help to control erosion. Areas that more sloping parts of the landscape; and Siskiyou soils on have been cut and filled are easily eroded unless they are ridges and convex slopes. Also included are small areas of treated. Seeding, mulching, and benching these areas help poorly drained soils near drainageways and on concave to control erosion. Steep yarding paths, skid trails, and slopes, soils that are similar to the Wolfpeak soil but have firebreaks are subject to rilling and gullying unless they are bedrock within a depth of 60 inches, and Wolfpeak soils that protected by a plant cover or adequate water bars, or both. have slopes of less than 12 or more than 35 percent. Cutbanks occasionally slump when the soil is saturated. Included areas make up about 20 percent of the total This unit is subject to slumping, especially in areas acreage. adjacent to drainageways. Road failure and landslides are Permeability is moderately slow in the Wolfpeak soil. likely to occur after road construction and clearcutting. Skid Available water capacity is about 8 inches. The effective trails and unsurfaced roads may be impassable during rooting depth is 60 inches or more. Runoff is medium, and rainy periods. Logging roads require suitable surfacing for the hazard of water erosion is moderate or high. year-round use. This unit is used for timber production and wildlife Undesirable plants limit natural or artificial reforestation habitat. It is suited to the production of Douglas fir. Other unless intensive site preparation and maintenance species that grow on this unit include ponderosa pine, measures are applied. Reforestation can be sugar pine, and California black oak. The understory accomplished by planting Douglas fir seedlings. Mulching vegetation includes canyon live oak, deerbrush, and around seedlings helps to maintain the moisture supply in western fescue. summer and minimizes competition from undesirable On the basis of a 100-year site curve, the mean site plants. index for Douglas fir is 120. The yield at culmination of the A high temperature in the surface layer and an mean annual increment is 6,900 cubic feet per acre in a insufficient moisture supply in summer increase the fully stocked, even-aged stand of trees at 60 years and seedling mortality rate. To compensate for the expected 31,840 board feet per acre (Scribner rule) at 160 years. On high mortality rate, the larger seedlings or a greater number the basis of a 50-year curve, the mean site index is 85. of seedlings should be planted. When the The main limitations affecting timber production are erosion, compaction, seedling mortality, and plant when the soil is wet. Using low-pressure ground equipment increases forage production and reduces the risk of causes less damage to the soil and helps to maintain erosion. productivity. Compaction can be minimized by using The vegetative site is Mixed Conifer-Chinkapin- suitable methods of harvesting, laying out skid trails in Sedge Forest. advance, and harvesting timber when the soil is least susceptible to compaction. Ripping skid trails and landings 203F-Woodcock stony loam, 35 to 55 percent south when the soil is dry can improve the growth of plants. slopes. This very deep, well drained soil is on hillslopes. It Properly designed road drainage systems that include formed in colluvium derived from andesite. Elevation is carefully located culverts help to control erosion. Seeding, 3,800 to 6,500 feet. The mean annual precipitation is 25 to mulching, and benching areas that have been cut and filled 35 inches, the mean annual temperature is 40 to 43 also help to control erosion. Steep yarding paths, skid trails, degrees F, and the average frost-free period is less than and firebreaks are subject to rilling and gullying unless they 100 days. The native vegetation is mainly conifers and an are protected by a plant cover or adequate water bars, or understory of grasses, shrubs, and forbs. both. Cutbanks occasionally slump when the soil is Typically, the surface is covered with a layer of needles saturated. and twigs about 1 inch thick. The surface layer is dark Constructing logging roads on the steeper slopes can reddish brown stony loam about 4 inches thick. The next result in a high risk of erosion. Material that is discarded layer is dark reddish brown very gravelly loam about 12 when the roads are built can damage vegetation and is a inches thick. The subsoil is dark reddish brown very potential source of sedimentation. If the material becomes gravelly clay loam about 23 inches thick: The substratum to saturated, avalanches of debris can occur. End hauling of a depth of 62 inches is dark reddish brown gravelly clay the waste material minimizes damage to the vegetation loam. The depth to bedrock is 60 inches or more. downslope and reduces the risk of sedimentation. Skid trails Included in this unit are small areas of Merlin soils and and unsurfaced roads may be impassable during rainy Rock outcrop on ridges and convex slopes, Pokegema periods. Logging roads require suitable surfacing for soils on the less sloping parts of the landscape, and soils year-round use. that are similar to the Woodcock soil but have bedrock Undesirable plants limit natural or artificial reforestation within a depth of 60 inches. Also included are small areas unless intensive site preparation and maintenance of Woodcock soils that have slopes of less than 35 or more measures are applied. Reforestation can be accomplished than 55 percent. Included areas make up about 15 percent by planting ponderosa pine and Douglas fir seedlings. of the total acreage. Mulching around seedlings helps to maintain the moisture Permeability is moderate in the Woodcock soil. Available supply in summer and minimizes competition from water capacity is about 4 inches. The effective rooting depth undesirable plants. is 60 inches or more. Runoff is rapid, and the hazard of The main limitations affecting livestock grazing are water erosion is high. erosion, compaction, and the slope. The native vegetation This unit is used for timber production, livestock suitable for grazing includes western fescue, sedge, grazing, and wildlife habitat. mountain brome, and tall trisetum. If the understory is This unit is suited to the production of Douglas fir and overgrazed, the proportion of preferred forage plants ponderosa pine. Other species that grow on this unit include decreases and the proportion of less preferred forage white fir, incense cedar, and sugar pine. The understory plants increases. vegetation includes sierra chinkapin, tall Oregongrape, and A planned grazing system that includes timely deferment western fescue. of grazing, rotation grazing, and proper livestock distribution On the basis of a 100-year site curve, the mean site helps to prevent overgrazing of the understory and damage index is 105 for Douglas fir and 95 for ponderosa pine. The to the soil. Grazing should be delayed until the more yield of ponderosa pine at culmination of the mean annual desirable forage plants have achieved enough growth to increment is 3,760 cubic feet per acre in a fully stocked, withstand grazing pressure and the soil is firm enough to even-aged stand of trees at 40 years and 43,160 board feet withstand trampling by livestock. per acre (Scribner rule) at 130 years. Thinning, logging, and fire reduce the density of the The main limitations affecting timber production are the overstory canopy and increase the production of slope, erosion, compaction, seedling mortality, and plant understory vegetation. Areas that support a large amount competition. Wheeled and tracked logging equipment can of competing vegetation can be improved by prescribed be used in the less sloping areas, but cable yarding burning or by chemical or mechanical treatment. Seeding generally is safer and results in less disturbed areas to suitable plants surface disturbance. If the soil is excessively disturbed forage plants decreases and the proportion of less when timber is harvested or logging roads are built, a larger preferred forage plants increases. number of rock fragments is left on the surface. Using A planned grazing system that includes timely deferment standard wheeled and tracked equipment when the soil is of grazing, rotation grazing, and proper livestock distribution moist causes rutting and compaction. Puddling can occur helps to prevent overgrazing of the understory and damage when the soil is wet. Using low-pressure ground equipment to the soil. Grazing should be delayed until the more causes less damage to the soil and helps to maintain desirable forage plants have achieved enough growth to productivity. Compaction can be minimized by using withstand grazing pressure and the soil is firm enough to suitable methods of harvesting, laying out skid trails in withstand trampling by livestock. advance, and harvesting timber when the soil is least Thinning, logging, and fire reduce the density of the susceptible to compaction. Ripping skid trails and landings overstory canopy and increase the production of when the soil is dry can improve the growth of plants. understory vegetation. Areas that support a large amount Properly designed road drainage systems that include of competing vegetation can be improved by prescribed carefully located culverts help to control erosion. Seeding, burning or by chemical or mechanical treatment. Seeding mulching, and benching areas that have been cut and filled disturbed areas to suitable plants increases forage also help to control erosion. Steep yarding paths, skid trails, production and reduces the risk of erosion. and firebreaks are subject to rilling and gullying unless they The vegetative site is Mixed Conifer-Chinkapin- are protected by a plant cover or adequate water bars, or Sedge Forest. both. Cutbanks occasionally slump when the soil is saturated. 204E-Woodcock-Pokegema complex, 12 to 35 Constructing logging roads on the steeper slopes can percent north slopes. This map unit is on hillslopes. result in a high risk of erosion. Material that is discarded Elevation is 3,800 to 6,500 feet. The mean annual when the roads are built can damage vegetation and is a precipitation is 25 to 35 inches, the mean annual potential source of sedimentation. If the material becomes temperature is 40 to 43 degrees F, and the average saturated, avalanches of debris can occur. End hauling of frost-free period is less than 100 days. The native the waste material minimizes damage to the vegetation vegetation is mainly conifers and an understory of downslope and reduces the risk of sedimentation. Skid trails grasses, shrubs, and forbs. and unsurfaced roads may be impassable during rainy This unit is about 60 percent Woodcock soil and 25 periods. Logging roads require suitable surfacing for percent Pokegema soil. The components of this unit occur year-round use. as areas so intricately intermingled that mapping them A high temperature in the surface layer during summer separately was not practical at the scale used. and the low available water capacity increase the seedling Included in this unit are small areas of Merlin soils and mortality rate. The large number of rock fragments in the Rock outcrop on ridges and convex slopes, Klamath soils soil also increases the seedling mortality rate. To near drainageways and on concave slopes, soils that are compensate for the expected high mortality rate, the larger similar to the Woodcock soil but have bedrock within a seedlings or a greater number of seedlings should be depth of 60 inches, and soils that are similar to the planted. When the timber is harvested, leaving some of the Pokegema soil but have bedrock at a depth of less than 40 larger trees unharvested provides shade for seedlings. The or more than 60 inches. Also included are small areas of seedling mortality rate also can be reduced by providing Woodcock and Pokegema soils that have slopes of less artificial shade for seedlings. Reforestation can be than 12 or more than 35 percent. Included areas make up accomplished by planting ponderosa pine and Douglas fir about 15 percent of the total acreage. seedlings. The Woodcock soil is very deep and well drained. It Undesirable plants limit natural or artificial formed in colluvium derived dominantly from andesite. reforestation unless intensive site preparation and Typically, the surface is covered with a layer of needles and maintenance measures are applied. Mulching around twigs about 1 inch thick. The surface layer is dark reddish seedlings helps to maintain the moisture supply in brown stony loam about 4 inches thick. The next layer is summer and minimizes competition from undesirable dark reddish brown very gravelly loam about 12 inches plants. thick. The subsoil is dark reddish brown very gravelly clay The main limitations affecting livestock grazing are loam about 23 inches thick. The substratum to a depth of 62 erosion, compaction, and the slope. The native vegetation inches is dark reddish suitable for grazing includes western fescue, sedge, mountain brome, and tall trisetum. If the understory is overgrazed, the proportion of preferred brown gravelly clay loam. The depth to bedrock is 60 Ripping skid trails and landings when the soils are dry can inches or more. improve the growth of plants. Permeability is moderate in the Woodcock soil. Available Properly designed road drainage systems that include water capacity is about 4 inches. The effective rooting depth carefully located culverts help to control erosion. Seeding, is 60 inches or more. Runoff is medium, and the hazard of mulching, and benching areas that have been cut and filled water erosion is moderate. also help to control erosion. Steep yarding paths, skid trails, The Pokegema soil is deep and well drained. It formed in and firebreaks are subject to rilling and gullying unless they colluvium derived dominantly from andesite. Typically, the are protected by a plant cover or adequate water bars, or surface is covered with a layer of needles and twigs about both. Skid trails and unsurfaced roads may be impassable 1/2 inch thick. The surface layer is dark reddish brown loam during rainy periods. Logging roads require suitable about 8 inches thick. The upper 8 inches of the subsoil is surfacing for year-round use. dark reddish brown clay loam. The lower 22 inches is dark Undesirable plants limit natural or artificial reforestation reddish brown gravelly clay. The substratum is dark reddish unless intensive site preparation and maintenance brown and reddish brown gravelly clay about 14 inches measures are applied. Reforestation can be accomplished thick. Weathered bedrock is at a depth of about 52 inches. by planting ponderosa pine and Douglas fir seedlings. The depth to bedrock ranges from 40 to 60 inches. In some Mulching around seedlings helps to maintain the moisture areas the surface layer is stony. supply in summer and minimizes competition from Permeability is moderately slow in the Pokegema soil. undesirable plants. Available water capacity is about 6 inches. The effective Severe frost can damage or kill seedlings. In the less rooting depth is 40 to 60 inches. Runoff is medium, and sloping areas where air drainage may be restricted, proper the hazard of water erosion is moderate. timber harvesting methods can reduce the effect of frost on This unit is used for timber production, livestock regeneration. grazing, and wildlife habitat. The main limitations affecting livestock grazing are This unit is suited to the production of Douglas fir and compaction and erosion. The native vegetation suitable for ponderosa pine. Other species that grow on this unit include grazing includes western fescue, sedge, mountain brome, white fir, incense cedar, and sugar pine. The understory and tall trisetum. If the understory is overgrazed, the vegetation includes sierra chinkapin, tall Oregongrape, and proportion of preferred forage plants decreases and the western fescue. proportion of less preferred forage plants increases. On the basis of a 100-year site curve, the mean site A planned grazing system that includes timely deferment index for Douglas fir is 110 on the Woodcock soil and 120 of grazing, rotation grazing, and proper livestock distribution on the Pokegema soil. helps to prevent overgrazing of the understory and damage On the basis of a 100-year site curve, the mean site to the soils. Grazing should be delayed until the more index for ponderosa pine is 105 on both the Woodcock and desirable forage plants have achieved enough growth to Pokegema soils. The yield at culmination of the mean withstand grazing pressure and the soils are firm enough to annual increment is 4,480 cubic feet per acre in a fully withstand trampling by livestock. stocked, even-aged stand of trees at 40 years and 50,040 Thinning, logging, and fire reduce the density of the board feet per acre (Scribner rule) at 120 years. overstory canopy and increase the production of The main limitations affecting timber production are understory vegetation. Areas that support a large amount erosion, compaction, and plant competition. Wheeled and of competing vegetation can be improved by prescribed tracked logging equipment can be used in the less sloping burning or by chemical or mechanical treatment. Seeding areas, but cable yarding generally is safer in the more disturbed areas to suitable plants increases forage sloping areas and results in less surface disturbance. If the production and reduces the risk of erosion. soils are excessively disturbed when timber is harvested or The vegetative site is Mixed Conifer-Chinkapin- logging roads are built, a larger number of rock fragments is Sedge Forest. left on the surface. Using standard wheeled and tracked equipment when the soils are moist causes rutting and 205E-Woodcock-Pokegema complex, 12 to 35 compaction. Puddling can occur when the soils are wet. percent south slopes. This map unit is on hillslopes. Using low-pressure ground equipment causes less damage Elevation is 3,800 to 6,500 feet. The mean annual to the soils and helps to maintain productivity. Compaction precipitation is 25 to 35 inches, the mean annual can be minimized by using suitable methods of harvesting, temperature is 40 to 43 degrees F, and the average laying out skid trails in advance, and harvesting timber when frost-free period is less than 100 days. The native the soils are least susceptible to compaction. vegetation is mainly conifers and an understory of The understory vegetation includes sierra chinkapin, tall grasses, shrubs, and forbs. Oregongrape, and western fescue. This unit is about 60 percent Woodcock soil and 25 On the basis of a 100-year site curve, the mean site percent Pokegema soil. The components of this unit occur index for Douglas fir is 105 on the Woodcock soil and 120 as areas so intricately intermingled that mapping them on the Pokegema soil. separately was not practical at the scale used. On the basis of a 100-year site curve, the mean site Included in this unit are small areas of Merlin soils and index for ponderosa pine is 95 on the Woodcock soil. The Rock outcrop on ridges and convex slopes, Klamath soils yield at culmination of the mean annual increment is 3,760 near drainageways and on concave slopes, soils that are cubic feet per acre in a fully stocked, even-aged stand of similar to the Woodcock soil but have bedrock within a trees at 40 years and 43,160 board feet per acre (Scribner depth of 60 inches, and soils that are similar to the rule) at 130 years. Pokegema soil but have bedrock at a depth of less than 40 On the basis of a 100-year site curve, the mean site or more than 60 inches. Also included are small areas of index for ponderosa pine is 105 on the Pokegema soil. The Woodcock and Pokegema soils that have slopes of less yield at culmination of the mean annual increment is 4,480 than 12 or more than 35 percent. Included areas make up cubic feet per acre in a fully stocked, even-aged stand of about 15 percent of the total acreage. trees at 40 years and 50,040 board feet per acre (Scribner The Woodcock soil is very deep and well drained. It rule) at 120 years. formed in colluvium derived dominantly from andesite. The main limitations affecting timber production are Typically, the surface is covered with a layer of needles and erosion, compaction, plant competition, and seedling twigs about 1 inch thick. The surface layer is dark reddish mortality. Wheeled and tracked logging equipment can be brown stony loam about 4 inches thick. The next layer is used in the less sloping areas, but cable yarding generally is dark reddish brown very gravelly loam about 12 inches safer in the more sloping areas and results in less surface thick. The subsoil is dark reddish brown very gravelly clay disturbance. If the soils are excessively disturbed when loam about 23 inches thick. The substratum to a depth of timber is harvested or logging roads are built, a larger 62 inches is dark reddish brown gravelly clay loam. The number of rock fragments is left on the surface. Using depth to bedrock is 60 inches or more. standard wheeled and tracked equipment when the soils are Permeability is moderate in the Woodcock soil. Available moist causes rutting and compaction. Puddling can occur water capacity is about 4 inches. The effective rooting depth when the soils are wet. Using low-pressure ground is 60 inches or more. Runoff is medium, and the hazard of equipment causes less damage to the soils and helps to water erosion is moderate. maintain productivity. Compaction can be minimized by The Pokegema soil is deep and well drained. It formed in using suitable methods of harvesting, laying out skid trails in colluvium derived dominantly from andesite. Typically, the advance, and harvesting timber when the soils are least surface is covered with a layer of needles and twigs about susceptible to compaction. Ripping skid trails and landings 1/2 inch thick. The surface layer is dark reddish brown loam when the soils are dry can improve the growth of plants. about 8 inches thick. The upper 8 inches of the subsoil is Properly designed road drainage systems that include dark reddish brown clay loam. The lower 22 inches is dark carefully located culverts help to control erosion. Seeding, reddish brown gravelly clay. The substratum is dark reddish mulching, and benching areas that have been cut and filled brown and reddish brown gravelly clay about 14 inches also help to control erosion. Steep yarding paths, skid trails, thick. Weathered bedrock is at a depth of about 52 inches. and firebreaks are subject to rilling and gullying unless they The depth to bedrock ranges from 40 to 60 inches. In some are protected by a plant cover or adequate water bars, or areas the surface layer is stony. both. Skid trails and unsurfaced roads may be impassable Permeability is moderately slow in the Pokegema soil. during rainy periods. Logging roads require suitable Available water capacity is about 6 inches. The effective surfacing for year-round use. rooting depth is 40 to 60 inches. Runoff is medium, and Undesirable plants limit natural or artificial reforestation the hazard of water erosion is moderate. unless intensive site preparation and maintenance This unit is used for timber production, livestock measures are applied. Reforestation can be accomplished grazing, and wildlife habitat. by planting ponderosa pine and Douglas fir seedlings. This unit is suited to the production of Douglas fir and Mulching around seedlings helps to maintain the moisture ponderosa pine. Other species that grow on this unit supply in summer and minimizes competition from include white fir, incense cedar, and sugar pine. undesirable plants. A high temperature in the surface layer and an insufficient moisture supply in summer increase the are similar to the Pokegema soil but have bedrock at a seedling mortality rate. The large number of rock fragments depth of less than 40 or more than 60 inches. Also in the Woodcock soil also increases the seedling mortality included are small areas of Woodcock and Pokegema soils rate. To compensate for the expected high mortality rate, that have slopes of less than 12 or more than 35 percent. the larger seedlings or a greater number of seedlings Included areas make up about 15 percent of the total should be planted. When the timber is harvested, leaving acreage. some of the larger trees unharvested provides shade for The Woodcock soil is very deep and well drained. It seedlings. formed in colluvium derived dominantly from andesite. Severe frost can damage or kill seedlings. In the less Typically, the surface is covered with a layer of needles and sloping areas where air drainage may be restricted, proper twigs about 1 inch thick. The surface layer is dark reddish timber harvesting methods can reduce the effect of frost on brown stony loam about 4 inches thick. The next layer is regeneration. dark reddish brown very gravelly loam about 12 inches The main limitations affecting livestock grazing are thick. The subsoil is dark reddish brown very gravelly clay compaction and erosion. The native vegetation suitable for loam about 23 inches thick. The substratum to a depth of grazing includes western fescue, sedge, mountain brome, 62 inches is dark reddish brown gravelly clay loam. The and tall trisetum. If the understory is overgrazed, the depth to bedrock is 60 inches or more. proportion of preferred forage plants decreases and the Permeability is moderate in the Woodcock soil. Available proportion of less preferred forage plants increases. water capacity is about 4 inches. The effective rooting depth A planned grazing system that includes timely deferment is 60 inches or more. Runoff is medium, and the hazard of of grazing, rotation grazing, and proper livestock distribution water erosion is moderate. helps to prevent overgrazing of the understory and damage The Pokegema soil is deep and well drained. It formed in to the soils. Grazing should be delayed until the more colluvium derived dominantly from andesite. Typically, the desirable forage plants have achieved enough growth to surface is covered with a layer of needles and twigs about withstand grazing pressure and the soils are firm enough to 1/2 inch thick. The surface layer is dark reddish brown loam withstand trampling by livestock. about 8 inches thick. The upper 8 inches of the subsoil is Thinning, logging, and fire reduce the density of the dark reddish brown clay loam. The lower 22 inches is dark overstory canopy and increase the production of reddish brown gravelly clay. The substratum is dark reddish understory vegetation. Areas that support a large amount brown and reddish brown gravelly clay about 14 inches of competing vegetation can be improved by prescribed thick. Weathered bedrock is at a depth of about 52 inches. burning or by chemical or mechanical treatment. Seeding The depth to bedrock ranges from 40 to 60 inches. In some disturbed areas to suitable plants increases forage areas the surface layer is stony. production and reduces the risk of erosion. Permeability is moderately slow in the Pokegema soil. The vegetative site is Mixed Conifer-Chinkapin- Available water capacity is about 6 inches. The effective Sedge Forest. rooting depth is 40 to 60 inches. Runoff is medium, and the hazard of water erosion is moderate. 206E-Woodcock-Pokegema complex, warm, 12 to 35 This unit is used for timber production, livestock percent slopes. This map unit is on hillslopes. It is mainly grazing, and wildlife habitat. on south-facing slopes. Elevation is 4,300 to 5,400 feet. The This unit is suited to the production of Douglas fir and mean annual precipitation is 25 to 35 inches, the mean ponderosa pine. Other species that grow on this unit annual temperature is 43 to 45 degrees F, and the average include white fir, incense cedar, and sugar pine. The frost-free period is less than 100 days. The native understory vegetation includes sierra chinkapin, vegetation is mainly conifers and an understory of grasses, antelope bitterbrush, and western fescue. shrubs, and forbs. On the basis of a 100-year site curve, the mean site This unit is about 60 percent Woodcock soil and 25 index for Douglas fir is 105 on the Woodcock soil and 120 percent Pokegema soil. The components of this unit occur on the Pokegema soil. as areas so intricately intermingled that mapping them On the basis of a 100-year site curve, the mean site separately was not practical at the scale used. index for ponderosa pine is 95 on the Woodcock soil. The Included in this unit are small areas of Merlin soils and yield at culmination of the mean annual increment is 3,760 Rock outcrop on ridges and convex slopes, Klamath soils cubic feet per acre in a fully stocked, even-aged stand of near drainageways and on concave slopes, soils that are trees at 40 years and 43,160 board feet per acre (Scribner similar to the Woodcock soil but have bedrock within a rule) at 130 years. depth of 60 inches, and soils that On the basis of a 100-year site curve, the mean site index for ponderosa pine is 105 on the Pokegema soil. The main limitations affecting livestock grazing are The yield at culmination of the mean annual increment is compaction and erosion. The native vegetation suitable for 4,480 cubic feet per acre in a fully stocked, even-aged grazing includes western fescue, sedge, mountain brome, stand of trees at 40 years and 50,040 board feet per acre and tall trisetum. If the understory is overgrazed, the (Scribner rule) at 120 years. proportion of preferred forage plants decreases and the The main limitations affecting timber production are proportion of less preferred forage plants increases. erosion, compaction, plant competition, and seedling A planned grazing system that includes timely deferment mortality. Wheeled and tracked logging equipment can be of grazing, rotation grazing, and proper livestock distribution used in the less sloping areas, but cable yarding generally is helps to prevent overgrazing of the understory and damage safer in the more sloping areas and results in less surface to the soils. Grazing should be delayed until the more disturbance. If the soils are excessively disturbed when desirable forage plants have achieved enough growth to timber is harvested or logging roads are built, a larger withstand grazing pressure and the soils are firm enough to number of rock fragments is left on the surface. Using withstand trampling by livestock. standard wheeled and tracked equipment when the soils are Thinning, logging, and fire reduce the density of the moist causes rutting and compaction. Puddling can occur overstory canopy and increase the production of when the soils are wet. Using low-pressure ground understory vegetation. Areas that support a large amount equipment causes less damage to the soils and helps to of competing vegetation can be improved by prescribed maintain productivity. Compaction can be minimized by burning or by chemical or mechanical treatment. Seeding using suitable methods of harvesting, laying out skid trails in disturbed areas to suitable plants increases forage advance, and harvesting timber when the soils are least production and reduces the risk of erosion, susceptible to compaction. Ripping skid trails and landings The vegetative site is Mixed Conifer-Bitterbrush- when the soils are dry can improve the growth of plants. Sedge Forest. Properly designed road drainage systems that include carefully located culverts help to control erosion. Seeding, 207E-Woodseye -Rock outcrop complex, 3 to 35 mulching, and benching areas that have been cut and filled percent slopes. This map unit is on hillslopes. Elevation also help to control erosion. Steep yarding paths, skid trails, is 4,000 to 6,000 feet. The mean annual precipitation is and firebreaks are subject to rilling and gullying unless they 30 to 55 inches, the mean annual, temperature is 40 to 45 are protected by a plant cover or adequate water bars, or degrees F, and the average frost-free period is less than both. Skid trails and unsurfaced roads may be impassable 100 days. The native vegetation is mainly grasses, during rainy periods. Logging roads require suitable shrubs, and forbs. surfacing for year-round use. This unit is about 65 percent Woodseye soil and 25 Undesirable plants limit natural or artificial reforestation percent Rock outcrop. The components of this unit occur unless intensive site preparation and maintenance as areas so intricately intermingled that mapping them measures are applied. Reforestation can be accomplished separately was not practical at the scale used. by planting ponderosa pine and Douglas fir seedlings. Included in this unit are small areas of Farva, Pinehurst, Mulching around seedlings helps to maintain the moisture Rustlerpeak, Snowlin, and Tatouche soils; poorly drained supply in summer and minimizes competition from soils near drainageways and on concave slopes; and soils undesirable plants. that are similar to the Woodseye soil but have bedrock at a A high temperature in the surface layer and an depth of less than 10 or more than 20 inches. Also included insufficient moisture supply in summer increase the are small areas of Woodseye soils that have slopes of more seedling mortality rate. The large number of rock fragments than 35 percent. Included areas make up about 10 percent in the Woodcock soil also increases the seedling mortality of the total acreage. rate. To compensate for the expected high mortality rate, The Woodseye soil is shallow and somewhat excessively the larger seedlings or a greater number of seedlings drained. It formed in colluvium derived dominantly from should be planted. When the timber is harvested, leaving andesite. Typically, the surface layer is dark brown very some of the larger trees unharvested provides shade for stony loam about 2 inches thick. The next layer is dark seedlings. brown very cobbly loam about 6 inches thick. The subsoil Severe frost can damage or kill seedlings. In the less also is dark brown very cobbly loam. It is about 10 inches sloping areas where air drainage may be restricted, proper thick. Bedrock is at a depth of about 18 inches. The depth to timber harvesting methods can reduce the effect of frost on bedrock ranges from 10 to 20 inches. regeneration. Permeability is moderate in the Woodseye soil. but have bedrock at a depth of less than 10 or more than Available water capacity is about 1 inch. The effective 20 inches. Also included are small areas of Woodseye rooting depth is 10 to 20 inches. Runoff is slow or soils that have slopes of less than 35 or more than 80 medium, and the hazard of water erosion is slight or percent. Included areas make up about 10 percent of the moderate. total acreage. Rock outcrop consists of areas of exposed bedrock. The Woodseye soil is shallow and somewhat excessively Runoff is very rapid in these areas. drained. It formed in colluvium derived dominantly from This unit is used for livestock grazing and wildlife andesite. Typically, the surface layer is dark brown very habitat. The main limitations affecting livestock grazing are stony loam about 2 inches thick. The next layer is dark compaction, erosion, the Rock outcrop, stones on the brown very cobbly loam about 6 inches thick. The subsoil surface, droughtiness, and the depth to bedrock. The also is dark brown very cobbly loam. It is about 10 inches vegetation suitable for grazing includes Idaho fescue, pine thick. Bedrock is at a depth of about 18 inches. The depth bluegrass, and bluebunch wheatgrass. If the range is to bedrock ranges from 10 to 20 inches. overgrazed, the proportion of preferred forage plants Permeability is moderate in the Woodseye soil. decreases and the proportion of less preferred forage Available water capacity is about 1 inch. The effective plants increases. Grazing should be delayed until the more rooting depth is 10 to 20 inches. Runoff is rapid, and the desirable forage plants have achieved enough growth to hazard of water erosion is high. withstand grazing pressure and the soil is firm enough to Rock outcrop consists of areas of exposed bedrock. withstand trampling by livestock. Runoff is very rapid in these areas. Suitable management practices on this unit include This unit is used for livestock grazing and wildlife habitat. proper grazing use, deferred grazing, rotation grazing, and The main limitations affecting livestock grazing are the brush control. Areas that support a large amount of slope, erosion, compaction, the Rock outcrop, stones on competing vegetation can be improved by chemical or the surface, droughtiness, and the depth to bedrock. The mechanical treatment. The use of ground equipment is not vegetation suitable for grazing includes Idaho fescue, pine practical because of the stones on the surface and the Rock bluegrass, and bluebunch wheatgrass. If the range is outcrop. overgrazed, the proportion of preferred forage plants This unit is poorly suited to range seeding. The main decreases and the proportion of less preferred forage limitations are the depth to bedrock, droughtiness, the Rock plants increases. Grazing should be delayed until the more outcrop, and the stones on the surface. The plants selected desirable forage plants have achieved enough growth to for seeding should be those that meet the seasonal withstand grazing pressure and the soil is firm enough to requirements of livestock or wildlife, or both. withstand trampling by livestock. This unit is limited as a site for livestock watering Suitable management practices on this unit include ponds and other water impoundments because of the proper grazing use, deferred grazing, rotation grazing, and slope and the depth to bedrock. brush control. Areas that support a large amount of The vegetative site is Loamy Juniper Scabland, 20-to competing vegetation can be improved by chemical or 30-inch precipitation zone. mechanical treatment. The use of ground equipment is not practical because of the stones on the surface, the Rock 207G-Woodseye -Rock outcrop complex, 35 to 80 outcrop, and the slope. percent slopes. This map unit is on hillslopes. Elevation is This unit is poorly suited to range seeding. The main 4,000 to 6,000 feet. The mean annual precipitation is 30 to limitations are the slope, droughtiness, the depth to 55 inches, the mean annual temperature is 40 to 45 bedrock, the Rock outcrop, and the stones on the surface. degrees F, and the average frost-free period is less than The plants selected for seeding should be those that meet 100 days. The native vegetation is mainly grasses, shrubs, the seasonal requirements of livestock or wildlife, or both. and forbs. The slope and the Rock outcrop limit access by This unit is about 60 percent Woodseye soil and 30 livestock. As a result, the less sloping areas tend to be percent Rock outcrop. The components of this unit occur overgrazed. Constructing trails or walkways allows as areas so intricately intermingled that mapping them livestock to graze in areas where access is limited. separately was not practical at the scale used. This unit is limited as a site for livestock watering Included in this unit are small areas of Farva, Pinehurst, ponds and other water impoundments because of the Rustlerpeak, Snowlin, and Tatouche soils; poorly drained slope and the depth to bedrock. soils near drainageways and on concave slopes; and soils that are similar to the Woodseye soil The vegetative site is Loamy Juniper Scabland, 20- to Included in this unit are small areas of Camas, Evans, 30-inch precipitation zone. and Newberg soils on flood plains; Central Point, Foehlin, Medford, and Takilma soils on terraces; and Abegg, 208C-Xerorthents-Dumps complex, 0 to 15 percent Josephine, Ruch, Shefflein, and Dumont soils on alluvial slopes. This map unit is in areas on flood plains, stream fans. Included areas make up about 35 percent of the total terraces, and alluvial fans where excavated material was acreage. deposited during mining operations. The material in this The Xerorthents vary too considerably to be classified at unit commonly is referred to as mine tailings. Slopes the series level. They are cobbly clay loam to extremely range from nearly level to hummocky. Elevation is 1,000 cobbly sandy loam and have as much as 90 percent gravel, to 4,100 feet. The mean annual precipitation is 20 to 50 cobbles, and stones. inches, the mean annual temperature is 43 to 54 degrees The Dumps consist mostly of gravel, cobbles, and F, and the average frost-free period is 100 to 180 days. stones and include little, if any, material of finer texture. The vegetation on the Xerorthents is mainly scattered Permeability, available water capacity, and the effective conifers and hardwoods and a sparse understory of rooting depth vary considerably in areas of this unit. There is grasses, shrubs, and forbs. The Dumps support very a seasonal high water table in winter and spring, particularly little, if any, vegetation. in areas on flood plains. This unit is about 35 percent Xerorthents and 30 This unit is a potential source of gravel. Most areas are percent Dumps. limited as sites for other uses. This unit is not assigned to a vegetative site. Prime Farmland

In this section, prime farmland is defined and the growing season. The slope ranges mainly from 0 to 6 soils in the survey area that are considered prime percent. farmland are listed. Soils that have a high water table, are subject to Prime farmland is of major importance in meeting the flooding, or are droughty may qualify as prime farmland Nation's short- and long-range needs for food and fiber. The soils if these limitations are overcome by drainage systems, acreage of high-quality farmland is limited, and the U.S. flood control, or irrigation. Onsite evaluation is necessary to Department of Agriculture recognizes that government at determine the effectiveness of corrective measures. More local, state, and federal levels, as well as individuals, must information about the criteria for prime farmland can be encourage and facilitate the wise use of our Nation's prime obtained at the local office of the Soil Conservation Service. farmland. A recent trend in land use has been the conversion of Prime farmland soils, as defined by the U.S. Department prime farmland to urban and industrial uses. The loss of of Agriculture,-are soils that are best suited to food, seed, prime farmland to other uses puts pressure on lands that forage, fiber, and oilseed crops. Such soils have properties are less productive than prime farmland. that favor the economic production of sustained high yields About 123,000 acres, or nearly 8.percent of the of crops. The soils need only to be treated and managed by survey area, would meet the requirements for prime acceptable farming methods. An adequate moisture supply farmland if an adequate and dependable supply of and a sufficiently long growing season are required. Prime irrigation water were available. farmland soils produce the highest yields with minimal The following map units meet the requirements for prime expenditure of energy and economic resources, and farming farmland. On some soils included in the list, measures that these soils results in the least damage to the environment. overcome a hazard or limitation, such as flooding, wetness, Prime farmland soils may presently be used as and droughtiness, are needed. The location of each map cropland, pasture, or woodland or for other purposes. They unit is shown on the detailed soil maps at the back of this either are used for food and fiber or are available for these publication. The soil qualities that affect use and uses. Urban or built-up land, public land, and water areas management are described in the section "Detailed Soil cannot be considered prime farmland. Urban or built-up Map Units." This list does not constitute a recommendation land is any contiguous unit of land 10 acres or more in size for a particular land use. that is used for such purposes as housing, industrial, and commercial sites and as sites for institutions or public 1B Abegg gravelly loam, 2 to 7 percent slopes buildings, small parks, golf courses, cemeteries, railroad (where irrigated) yards, airports, sanitary landfills, sewage treatment plants, 1C Abegg gravelly loam, 7 to 12 percent slopes and water-control structures. Public land is land not (where irrigated) available for farming in national forests, national parks, and 2A Abin silty clay loam, 0 to 3 percent slopes state parks and on military reservations. 8A Barhiskey gravelly loamy sand, 0 to 3 percent Prime farmland soils commonly receive an adequate and slopes (where irrigated) dependable supply of moisture from precipitation or 9A Barhiskey Variant gravelly loamy sand, 0 to 3 irrigation. The temperature and length of growing season percent slopes (where irrigated and drained) are favorable, and the level of acidity or alkalinity is 10B Barron coarse sandy loam, 0 to 7 percent acceptable. The soils have few, if any, rocks and are slopes (where irrigated) permeable to water and air. They are not excessively 31A Central Point sandy loam, 0 to 3 percent erodible or saturated with water for long periods and are not slopes frequently flooded during the 32B Clawson sandy loam, 2 to 5 percent slopes (where drained) 34B Coleman loam, 0 to 7 percent slopes (where 106C Lobert sandy loam, 0 to 12 percent slopes drained) (where irrigated) 43B Darow silty clay loam, 1 to 5 percent slopes 108B Manita loam, 2 to 7 percent slopes 51C Dumont gravelly clay loam, 1 to 12 percent 127A Medford silty clay loam, 0 to 3 percent slopes slopes 128B Medford clay loam, gravelly substratum, 0 to 7 55A Evans loam, 0 to 3 percent slopes percent slopes 61A Foehlin gravelly loam, 0 to 3 percent slopes 133A Newberg fine sandy loam, 0 to 3 percent 62C Freezener gravelly loam, 1 to 12 percent slopes (where irrigated) slopes 149B Pollard loam, 2 to 7 percent slopes 76A Gregory silty clay loam, 0 to 3 percent slopes 157B Ruch silt loam, 2 to 7 percent slopes (where drained) 158B Ruch gravelly silt loam, 2 to 7 percent slopes 86C Hukill gravelly loam, 1 to 12 percent slopes 162B Selmac loam, 2 to 7 percent slopes (where 97A Kerby loam, 0 to 3 percent slopes drained) 98A Kerby loam, wet, 0 to 3 percent slopes (where 163A Sevenoaks loamy sand, 0 to 3 percent slopes drained) (where irrigated) 100A Kubli loam, 0 to 3 percent slopes (where 164B Shefflein loam, 2 to 7 percent slopes drained) 192A Terrabella clay loam, 0 to 3 percent slopes 100B Kubli loam, 3 to 7 percent slopes (where (where drained) drained) 199C Wolfpeak sandy loam, 3 to 12 percent slopes Use and Management of the Soils

This soil survey is an inventory and evaluation of the land capability classification used by the Soil Conservation soils in the survey area. It can be used to adjust land uses Service is explained, and the estimated yields of the main to the limitations and potentials of natural resources and crops and hay and pasture plants are listed for each soil. the environment. Also, it can help avoid soil-related failures Planners of management systems for individual fields or in land uses. farms should consider the detailed information given in the In preparing a soil survey, soil scientists, description of each soil under "Detailed Soil Map Units." conservationists, engineers, and others collect extensive Specific information can be obtained from the local office of field data about the nature and behavioral characteristics of the Soil Conservation Service or the Cooperative Extension the soils. They collect data on erosion, droughtiness, Service. flooding, and other factors that affect various soil uses and In this survey area about 301,870 acres is in areas of management. Field experience and collected data on soil farms and ranches. About 59,782 acres of the farmland is properties and performance are used as a basis in irrigated. Among the crops grown in 1987 were 7,700 acres predicting soil behavior. of Bartlett and winter pears, 560 acres of other fruit and Information in this section can be used to plan the use nuts, 150 acres of grapes, 360 acres of vegetable and and management of soils for crops and pasture; as grazing nursery crops, 26,550 acres of hay and silage crops, 3,700 land and woodland; as sites for buildings, sanitary facilities, acres of grain, 460 acres of seed crops, and 20,300 acres of highways and other transportation systems, and parks and irrigated pasture. The cropland is mainly in the valleys of the other recreation facilities; and for wildlife habitat. It can be Rogue and Applegate Rivers and of Bear, Evans, and Butte used to identify the potentials and limitations of each soil Creeks. for specific land uses and to help prevent construction The soils in the surrey area have many characteristics failures caused by unfavorable soil properties. that affect their behavior and response to management for Planners and others using soil survey information can various uses. The productivity of each soil under given evaluate the effect of specific land uses on productivity and management practices can be maintained or improved only on the environment in all or part of the survey area. The if the unique characteristics of the soils are understood and survey can help planners to maintain or create a land use the best management practices are applied. pattern in harmony with the natural soil. One such characteristic is the tendency of the soils to Contractors can use this survey to locate sources of become compacted as a result of tillage, machinery traffic, sand and gravel, roadfill, and topsoil. They can use it to or livestock use during wet periods. Compaction commonly identify areas where bedrock, wetness, or very firm soil restricts permeability and root development, reduces the layers can cause difficulty in excavation. rate of water intake, and increases the runoff rate and the Health officials, highway officials, engineers, and others hazard of erosion. Under these conditions, the productivity may also find this survey useful. The survey can help them of the soils is reduced and the loss of soil and water is plan the safe disposal of wastes and locate sites for increased. Proper management practices can prevent pavements, sidewalks, campgrounds, playgrounds, lawns, compaction, maintain productivity, and protect the soils and trees and shrubs. from further degradation. The effects of erosion are most critical on the steeper Crops and Pasture slopes and on the soils that formed in granitic material. These effects include the loss of organic matter, the By Ron Mobley, Oregon State University Extension Service, and breakdown of the natural structure of the soils, and Nicola Giardina, soil conservationist, Soil Conservation Service. General management needed for crops and for hay and pasture is suggested in this section. The system of alteration of the texture of the soils through the loss of clay restrict the movement of water. As a result, the soils and silt, all of which result in deterioration of the tilth, have a seasonal high water table. workability, and productivity of the soils. Drainage can be improved in most areas by installing The productivity of the soils is reduced through the loss surface or subsurface drainage systems. Surface systems of nutrients and soil particles. The soil resource is not include diversions, open drainage ditches, grassed renewed through natural processes within a short period. waterways, and land shaping, which eliminates Many hundreds of years is required to replace part of an depressions. Subsurface systems consist of either pattern eroded surface layer, although appropriate cultural or interceptor tile drains. practices and soil amendments can hasten the The problems associated with installing drainage systems redevelopment of the soil. Soil particles, nutrients, and are poor outlets, limited soil depth, and fine soil texture. If chemicals transported by water into streams and ponds outlets are not available, the site cannot be drained unless degrade the quality of the water. Erosion can increase the excess water is pumped away from the site. A shallow soil turbidity of streams and rivers and contaminate domestic depth increases installation costs and limits the water supplies. The deposition of eroding soil material can effectiveness of drainage systems. Drainage lines in fine destroy spawning beds for fish. Removing this material textured soils should -be closely spaced because these soils from irrigation and drainage ditches and from ponds is are slowly permeable. costly. Where the soils have been drained, a wider variety of The soils in the survey area that formed in granitic crops can be grown because of the improved movement of material, such as those of the Shefflein and Tallowbox water and better root aeration, which promotes the growth series, are highly susceptible to erosion. Special emphasis and penetration of roots. Drainage systems allow for better should be placed on practices that control erosion and water management, earlier warming of the soils, and better thus help to prevent the degradation of water quality. accessibility to the fields. Many management practices can control erosion. They Although there are many advantages to draining soils for include returning crop residue to the soil and growing agricultural purposes, natural swamps and marshes provide grasses and shrubs as cover crops. Such cover crops important habitat for many kinds of wildlife. Draining these protect the surface from the impact of raindrops or sprinkler areas destroys this habitat. The environmental impact of irrigation water and reduce the loss of both soil material and installing a drainage system should be carefully considered. water. The steeper soils are more susceptible to erosion Because of insufficient rainfall during the growing because the velocity of the runoff on such soils is greater. season, irrigation is necessary for high crop yields. The The problem is compounded on the longer slopes, which most important considerations in irrigated areas are the have greater concentrations of runoff. available water capacity and rate of water intake in the If farmed, loamy soils in areas on foothills where slopes soils, the needs of the crop, and the availability of irrigation are more than 10 percent are highly susceptible to erosion. water. The available water capacity is the amount of water Examples are Brader, Debenger, Ruch, and Shefflein soils. that soils can store for use by plants. The factors that affect Suitable management practices on these soils include this capacity are depth, texture, the content of rock minimizing tillage, farming on the contour, returning crop fragments, and the content of organic matter. residue to the soils, and terracing. For each kind of soil and The rate of water intake is determined by the texture, crop, specific management practices are needed to structure, and content of organic matter in the soils and by minimize erosion. the kind of land use. Sandy soils absorb water rapidly and Soil drainage is a concern in many areas. In some soils have a low available water capacity. Clayey soils absorb the seasonal high water table limits the choice of crops and water slowly and have a comparatively high available water management practices. The soils in the survey area that capacity. Water moves through soils that have good have a seasonal high water table are those of the Coker, structure at a more desirable rate than it does through soils Cove, Gregory, and Padigan series. The high water is that have poor structure. primarily a result of the topography and the internal Crops require water at critical periods if maximum quality characteristics of the soils. Drainage problems may be and production are to be achieved. To maintain a desirable compounded by the inefficient application of irrigation water. growth rate, enough soil moisture must be available to the As water flows along the natural contours of the landscape, crops. The number of acres that can be irrigated in a given it can become concentrated, thus saturating the soils. year is determined by the properties of the snowpack, the Layers of dense clay and other impervious layers restrict amount of water stored in the soils, and the streamflow. the rooting depth in Winlo, Langellain, and Kubli soils. They also The availability of irrigation water depends on the although the content of phosphorus and sulfur is low in competitive demands of agriculture, recreation, wildlife, some areas. industry, and municipalities. Irrigation systems should be Management of these clayey soils is difficult. designed for the greatest efficiency. Runoff or drainage Establishing fall-seeded crops in nonirrigated areas of the water can be filtered, collected, and then reused or soils is difficult because soil moisture conditions are returned to streams. unpredictable and frost heaving of seedlings occurs unless Sprinkler, furrow, border, flooding, and trickle irrigation the plants are well established before frost conditions systems commonly are used in the survey area. The system prevail in winter. used depends on the characteristics of the soils, the Because tilling is difficult, these clayey soils are better cropping system, the crops to be grown, the availability of suited to such crops as pears, apples, and perennial forage labor, and the cost. The water should not be applied at a crops than to annual crops. They are well suited to rate that exceeds the intake rate of the soils. permanent forage crops, which provide excellent ground Sprinkler irrigation is suitable on soils that have various cover in the steeper areas, where erosion is a hazard. slope ranges and rates of water intake and that are used for Some of the improved perennial grasses that can be grown various crops. Sprinkler irrigation systems are used to in the survey area are fescues and ryegrasses. The suitable control frost in spring and delay blossoming of fruit trees improved legumes grown for permanent forage include and grapevines. Few of the soils in the survey area are white clover and trefoil. Alfalfa generally grows best on soils suited to flood irrigation systems that include borders and that are characterized by good internal drainage; therefore, furrows because the soils so irrigated should be those that its production may be limited on these clayey soils because are nearly level and have uniform slopes. Such systems of their poor drainage in winter. Such crops as new pear require that the soils be leveled and graded. They may be plantings, vegetables, and berries may benefit from raised the best systems for certain row crops. Trickle irrigation beds or seedbeds established on prepared ridges 5 to 6 systems are very efficient because they apply water only to inches high. Subsoiling or ripping does not provide the root zone. They are used mainly in areas of vine and long-term benefits in areas of these soils because only two tree crops. or three irrigations or winter rains are needed to reseal the Fertilizer is needed to provide the nutrients required by profile. plants. For high yields. and the efficient use of fertilizer, a The management practices needed for the soils in the planned application program is needed. On all the soils in survey area to produce high yields of crops vary, the survey area, the amount of fertilizer and other depending on the kind of soil and the kind of crop. The amendments to be applied should be based on the results local office of the Cooperative Extension Service or of the of soil tests, on the needs of the crop, and on the Soil Conservation Service can provide information about expected level of yields. the management practices that are suitable on the various Organic farming has become popular in the survey area soils in the survey area. during recent years. Applications of organic matter, such as animal manure, green manure, plant refuse, and compost, Yields Per Acre maintain or improve soil productivity and are beneficial in draining and warming the soils. Adding organic matter helps The average yields per acre that can be expected of the coarse textured soils to retain moisture and plant nutrients principal crops grown under a high level of management and improves the workability, rate of water intake, structure, are shown in table 5. In any given year, yields may be and aeration of fine textured soils. higher or lower than those indicated in the table because of Many soils in the survey area have a high content of clay. variations in rainfall and other climatic factors. The Carney and Coker soils are examples. They have wide capability classification of each map unit also is shown in cracks when dry and are sticky and slick when wet. Other the table. characteristics of these soils are a slow rate of water The yields are based mainly on the experience and infiltration; the tenacious adherence of water to the clay records of farmers, conservationists, and extension particles, which makes it difficult for plants to extract water agents. Available yield data from nearby counties and from the soils and thus causes wilting of plants when the results of field trials and demonstrations also are soil moisture content is only 25 to 35 percent; a high considered. buffering capacity, which tends to tie up or hold fertilizer and The management needed to obtain the indicated yields the chemicals used for weed control and thus may require of the various crops depends on the kind of soil farmed that the application rate be increased; and a scarcity of and the crop grown. Management can include drainage, unusual fertility problems, erosion control, and protection from flooding; the proper planting and seeding rates; suitable high-yielding crop varieties; appropriate and timely tillage; control of weeds, plant diseases, and harmful insects; choice of plants or that require special conservation favorable soil reaction and optimum levels of nitrogen, practices, or both. phosphorus, potassium, and trace elements for each Class IV soils have very severe limitations that , reduce crop; effective use of crop residue, barnyard manure, and the choice of plants or that require very careful green manure crops; and harvesting that ensures the management, or both. smallest possible loss. Class V soils are not likely to erode but have other For yields of irrigated crops, it is assumed that the limitations, impractical to remove, that limit their use. irrigation system is adapted to the soils and to the crops Class VI soils have severe limitations that make them grown, that good-quality irrigation water is uniformly applied generally unsuitable for cultivation. as needed, and that tillage is kept to a minimum. Class VII soils have very severe limitations that make The estimated yields reflect the productive capacity of them unsuitable for cultivation. each soil for each of the principal crops. Yields are likely to Class VIII soils and miscellaneous areas have limitations increase as new production technology is developed. The that nearly preclude their use for commercial crop productivity of a given soil compared with that of other soils, production. however, is not likely to change. Capability subclasses are soil groups within one class. Crops other than those shown in table 5 are grown in the They are designated by adding a small letter, e, w, s, or c, to survey area, but estimated yields are not listed because the the class numeral, for example, Ile. The letter e shows that acreage of such crops presently is small. The local office of the main hazard is the risk of erosion unless close-growing the Soil Conservation Service or of the Cooperative plant cover is maintained; w shows that water in or on the Extension Service can provide information about the soil interferes with plant growth or cultivation (in some soils management and productivity of the soils for those crops. the wetness can be partly corrected by artificial drainage); s shows that the soil is limited mainly because it is shallow, Land Capability Classification droughty, or stony; and c, used in only some parts of the United States, shows that the chief limitation is climate that Land capability classification shows, in a general way, is very cold or very dry. the suitability of soils for most kinds of field crops. Crops that In class I there are no subclasses because the soils of require special management are excluded. The soils are this class have few limitations. Class V contains only the grouped according to their limitations for field crops, the risk subclasses indicated by w, s, or c because the soils in class of damage if they are used for crops, and the way they V are subject to little or no erosion. They have other respond to management. The criteria used in grouping the limitations that restrict their use to pasture, rangeland, soils do not take into account major and generally expensive woodland, wildlife habitat, or recreation. landforming that would change slope, depth, or other The capability classification of each map unit is given in characteristics of the soils, nor do they include possible but table 5. unlikely major reclamation projects. Capability classification is not a substitute for interpretations designed to show Livestock Grazing suitability and limitations of groups of soils for rangeland, for woodland, and for engineering purposes. By Gene Hickman, range conservationist, Soil Conservation In the capability system, soils generally are grouped at Service. three levels-capability class, subclass, and unit (24). Only In areas that have similar climate and topography, class and subclass are used in this survey. differences in the kind and amount of vegetation produced Capability classes, the broadest groups, are are closely related to the kind of soil. Effective management designated by Roman numerals I through VIII. The is based on the relationship between the soils and numerals indicate progressively greater limitations and vegetation and water. narrower choices for practical use. The classes are Table 6 shows, for each soil, the vegetative site; the defined as follows: total annual production of vegetation in favorable, normal, Class I soils have few limitations that restrict their and unfavorable years; the characteristic vegetation; and use. the average percentage of each species. Explanation of Class II soils have moderate limitations that reduce the the column headings in table 6 follows. choice of plants or that require moderate conservation A vegetative site is a distinctive kind of site that practices. produces a characteristic natural plant community that Class III soils have severe limitations that reduce the differs from natural plant communities on other vegetative sites in kind, amount, and proportion of forage plants. The relationship between the soils and does not have a specific meaning that pertains to the vegetation in the survey area was ascertained during this present plant community in a given use. survey; thus, vegetative sites generally can be determined The objective in managing vegetative sites is to control directly from the soil map. Soil properties that affect grazing so that the plants growing on a site are about the moisture supply and plant nutrients have the greatest same in kind and amount as the potential natural plant influence on the productivity of plants. Soil reaction, soil community for that site. Such management generally results temperature, and a seasonal water table are also in the optimal production of vegetation, control of important. undesirable brush species, conservation of water, and Total production is the amount of vegetation that can be control of erosion. Sometimes, however, a site condition expected to grow annually in a well managed area that somewhat below the potential meets grazing needs, supports the potential natural plant community. It includes provides wildlife habitat, and protects soil and water all vegetation, whether or not it is palatable to grazing resources. animals. It includes the current year's growth of leaves, Historically, raising livestock, both sheep and cattle, has twigs, and the fruit of woody plants up to 4.5 feet high. It been vital to the economy of this survey area. Although the does not include the increase in stem diameter of trees and number of livestock has declined in recent years, livestock shrubs. It is expressed in pounds per acre of air-dry raising is still vital to the local economy and to the vegetation for favorable, normal, and unfavorable years. In a numerous ranch owners in the southern and eastern parts favorable year, the amount and distribution of precipitation of the survey area. and the temperatures make growing conditions substantially Sheep ranching has changed from range-type operations better than average. In a normal year, growing conditions to farm-type operations. Limited grazing of sheep in forest are about average. In an unfavorable year, growing plantations as an alternative to applications of herbicide is conditions are well below average, generally because of low being studied. These studies are providing very available soil moisture. encouraging results. Dry weight is the total annual yield per acre of air-dry Some of the considerations that are pertinent to grazing vegetation. Yields are adjusted to a common percent of management in this survey area are the season of use, air-dry moisture content. The relationship of green weight to forage production, proper grazing use, water availability, air-dry weight varies according to such factors as exposure, grazing systems, fencing, deferred grazing, and rest amount of shade, recent rains, and unseasonable dry periods. periods. Season of use.-This is the time of the year when a site Characteristic vegetation-the grasses , forbs, shrubs, and is suitable for livestock grazing. It is determined by such trees that make up most of the potential natural plant factors as the length of the growing season, the kinds of community on each soil-is listed by common name. Under soil on the site, and the effects of snow and other climatic composition, the expected percentage of the total annual considerations. The season of use varies considerably, production is given for each species making up the depending on aspect, elevation, and climatic zones. characteristic vegetation. The percent composition value is Sites that are characterized by medium textured, well determined by air-dry weight or by the occurrence of drained soils and are dominated by white oak, juniper, and individual species. If dry weight entries are given in the total wedgeleaf ceanothus or are open grassland can be grazed production column, the percent composition is by air-dry from early in spring to late in fall. Sites in poor condition may weight. If there are no entries in the total production column, have palatable available forage only in spring. Wet, clayey the percent composition entries were determined by the soils are subject to soil displacement and structural damage occurrence of individual species. The amount of vegetation if they are grazed. Grazing on these soils should be delayed that can be used as forage depends on the kinds of grazing until late in spring, after most of the rainy season has animals and on the grazing season. passed. Because the growing season is short and the soils Management of vegetative sites requires a knowledge of are wet much of the time, meadows should be grazed from the kinds of soil and of the potential natural plant summer until early in fall. Forested sites at the lower community. It also requires an evaluation of the present elevations can be grazed from late in spring through fall, condition of the site. Site condition is determined by and those at the higher elevations can be grazed from comparing the present plant community with the potential summer to early in fall. natural plant community for a particular site. The more Forage production. -Forage production varies greatly closely the existing community resembles the potential from site to site and under different conditions on the same community, the better the site condition. Site condition is an site. The palatable or preferred grazing species are not ecological rating only. It always known, especially in forested areas, unless the diet or use patterns of livestock are closely grazing sites in the survey area, although increased monitored. Fine- or soft-leaved grasses and edible forbs are production may not be economically feasible. Among the the main forage plants grazed by cattle, although a number practices that can increase production are applying of palatable shrubs can provide forage from late in summer fertilizer, spreading water, thinning dense forests, seeding through fall. grasses and legumes, and converting forest sites to Under normal conditions, meadows in good condition permanent dryland pasture. provide the highest forage yields. Deterioration of the Applications of fertilizer generally are limited to special meadows to poor condition results in changes in plant seeded areas and to some meadows. An economic composition and less palatable and less usable forage. response is not always ensured, and test plots may be Open grassland and sites that support oak and pine are needed to determine the response. Applying fertilizer is not next highest in natural productivity. As with meadow sites, likely to be economical in most other areas of native deterioration of these sites to poor condition reduces forage forage. yields because of the invasion of unpalatable, weedy Spreading water on meadows can increase forage species. The grazing sites in areas of scabland are the production in some areas. On meadows that dry out early, lowest in natural productivity. On these sites there is little this practice can prolong the growing season and improve potential for improvement of forage production under any the quality of the forage. known management or improvement practices. Heavy thinning of dense forest increases the amount of Forested sites provide a wide range of forage yields, light that reaches the understory. It improves the growth of even on the same vegetative site. During the successional understory plants, especially native grasses, and permits stages of a stand, the availability of forage changes stagnated timber stands to increase their growth rate. The considerably in response to shading and competition among response of forage to thinning is temporary if the canopy is species. As timber stands become more mature, especially allowed to close. It varies, depending on the site, and the those of true fir and Douglas fir, most grazable areas economic advantage of applying this practice should be gradually develop into brush fields, which provide less considered on a site-by-site basis. Thinning mixed stands forage for livestock. As these sites pass from the dense of Douglas fir and ponderosa pine or of ponderosa pine and brush stage through the sapling and young pole stages, little oak results in the greatest natural increase in forage forage is produced or used by livestock. As the canopy production. begins to open in those stands that are in the older pole On some recently burned sites, seeding suitable species stage and in mature stands, forage again becomes of grasses and legumes results in the establishment of good available. Forage production on forested sites is influenced stands of forage. In forested areas these stands may to a great extent by the timber harvesting methods used. deteriorate after several years if brush fields develop and Harvesting practices that maintain an open canopy tend to take over the sites; however, at some study locations in the promote long-term production of a higher amount of forage. survey area, such seedings have retarded the return of Cattle prefer to graze in areas that are open or only brush following a fire. Care is advised in the seeding of very lightly shaded. Livestock generally avoid or make only burned areas that were formerly oak-savanna areas, limited use of forage on steep, timbered slopes. Heavily grassland, or idle fields. If these areas supported weedy shaded sites are grazed very little under any conditions, stands of annual forbs and grasses before burning, weed but they may be used as bedding areas on warm days or control probably is needed if seeding is to be successful. cold nights. Consequently, most grazing in forested areas Forage species are seeded in some areas of oak, pine, or takes place in natural openings, in very lightly shaded grassland after the sites have been prepared by methods areas, in clearings, in newly logged areas, in recently other than burning. Clearing brush, farming, applying burned areas, on landings, and in roadside areas. herbicides, and using a range drill are techniques that are Because of all these factors, predicting the total amount employed at times to improve the site. The economical value of usable forage for a given site is difficult even when the of seeding forage species has a great bearing on the history of the site is available. Generally, however, it can be feasibility of seeding a particular site. The species seeded assumed that the forage yield will be 50 to 300 pounds per and the seeding methods used should be restricted to those acre for most forested communities in the optimum stages of that local experience has shown to be successful on the forage production during the development of the stand. soils and sites involved. Forage production could be increased on most After forested areas are logged, seeding along forest roads, on landings, and in other critical areas is nearly always successful if proper seeding methods are used. In some areas the purpose of seeding is both erosion control and forage production. Care is needed to ensure that some sites where access is poor or the topography is the species selected for seeding and the seeding rates are rough. Many areas near water sources are overgrazed. those that achieve the management objective and that are Where overgrazing is a concern, adjustments in the adapted to the local environment. Seedings in grazing program should be considered. tree-regeneration areas generally should be light. Seeding Grazing systems. -A grazing system is the planned nonaggressive species that do not form sod helps to control sequence and timing of grazing in an area. The sequence competition with tree seedlings. Roadways and other areas commonly is planned for as long as 5 years. Yearly that have been cut and filled should be stabilized by seeding modifications in the plan can be made in response to aggressive species at heavy rates. changes in the growing season, economic conditions, or Most forested sites that are steeply sloping or are other management considerations. Planned grazing characterized by soils that formed in material derived from systems are important in accomplishing management granitic rock, except those at the highest elevations, can be objectives and are applicable to all kinds of grazing land. If converted to permanent dryland pasture if forest the system is to work well, some flexibility is needed in management is not the long-term objective. Land that is making the adjustments required because of changes in removed from forest production can produce a wide variety livestock needs, weather, the availability of water, and the of improved forage species. Yields of forage on these sites amount or kind of available forage. may be 3 to 5 times greater than those in the former A grazing system is used to achieve proper use of the natural stands. key forage species and proper timing of the grazing. It Proper grazing use.-A proper degree of grazing use is promotes more efficient use of the entire area being grazed. achieved when the percentage, on a dry -weight basis, of the It also allows grazing and rest periods to be scheduled over total annual production of the key species planned for a period of years, or only for a year, in response to changes grazing is not excessive. The percentage of forage removed in forage quality, variations in the season of use on different in any one season is limited to that which is consistent with sites, and the long-term physiological requirements of the the physiological limitations of the plants. Proper grazing plants. A special function of grazing systems is to allow use is related to the objectives of specific land users. Other coordination of grazing periods with other management factors to be considered are the amount of residual growth activities, such as logging, seeding, breeding, and calf needed to provide habitat for wildlife and the amount of weaning. stubble and litter needed to protect the soils. Fencing.-Proper control of cattle is not feasible unless When the degree of use is planned, the grazing pressure grazing units or pastures are correctly designed. It is that plants can withstand and still make adequate recovery achieved by selecting a pasture size according to such should be considered. The degree of use can be greater in factors as the size of the herd, the type of forage available, the dormant season, when forage species are more tolerant the topography, and the boundaries of the vegetative site. In of grazing, than during the growing season. some areas natural barriers reduce the amount of fencing Management objectives may further restrict the degree required. Fencing can separate highly contrasting areas. of use. For example, grazing plans for riparian areas may For example, they can separate areas of wet, clayey soils allow very limited use of willow or aspen when these from areas of well drained soils. Sites that differ species are critical to site improvement. Grazing considerably in their season of use should be divided if objectives in a forest plantation may require heavy use of feasible. For example, moist, north-facing slopes should be the key forage grasses to reduce their competition with divided from dry, south-facing slopes, and areas at low tree seedlings for moisture or to reduce the risk of fire. elevations should be divided from areas at high elevations. Water availability.-Because the distribution of grazing is Cross-fencing is useful in separating seeded areas or closely associated with the location of livestock watering meadows from other areas and in reducing the size of large facilities, the availability of water is an important pastures. management concern. The distribution of livestock and the Fences should be located along routes that permit use of forage can be controlled by improving the water construction and maintenance costs to be minimized and supply through the development of springs, ponds, wells, or allow management objectives to be met. Careful pipelines. The watering facilities can be 1.5 to 2.0 miles planning is needed to avoid conflicts with other uses, apart on some grazing sites that are gently sloping and such as timber production and recreation. readily accessible. The facilities should be more closely Deferred grazing.-This is the practice of delaying spaced, however, on grazing either until the dormant season or until the growth cycle and seed production of the key species are completed. It allows the plants enough time to recover from the previous years of grazing and to develop Vegetative zone 1. This zone includes general soil ripe seed, which is needed if new seedlings are to be map units 1, 2, 3, and 4. The soils in this zone are in the established. Deferred grazing can be scheduled periodically driest and warmest parts of the survey area. The over several years. When incorporated into a grazing temperature varies considerably from one season to system, it can be applied on a set of pastures over several another. The mean annual precipitation ranges from years so that some or all of the pastures receive this about 18 inches to 24 inches. treatment. Although farming and urban development have Rest periods .-Resting pastures, either for a full season permanently changed much of the former plant cover in this or for a longer period, is sometimes necessary. The grazing zone, sizable stands of native vegetation remain. The system may provide for the total rest of some pastures for native plant cover grows in areas of open grassland or special purposes. Examples of these purposes are allowing slowly growing Oregon white oak-ponderosa pine savanna. protective litter to build up, reserving forage to meet wildlife The soils in most of these areas are shallow, droughty, or needs, permitting seedlings to become established, clayey. In some areas, however, they are deep, well allowing riparian habitat to recover, allowing recovery drained, and loamy and support dense stands of rapidly following a fire, and providing short-term protection of growing ponderosa pine, mixed oak, and Pacific madrone. plantations. Livestock should be excluded for long periods The climate generally is too dry for Douglas fir, although in some areas, such as those where erosion is an important minor amounts grow in favorable locations. The soils on concern. flood plains and the very poorly drained soils on terraces are very productive. They support meadow vegetation or Vegetative Zones and Sites dense mixtures of cottonwood and other deciduous trees and shrubs. By Gene Hickman, range conservationist, Soil Conservation Service. Vegetative zone 2. This zone includes general soil This survey area is in the center of a region of great map units 5, 11, 13, and 20. It is on mountains at low environmental diversity. The unique broad patterns of elevations and in areas adjacent to valley terraces and vegetation in the area are characterized as vegetative flood plains. Elevation typically is less than 4,000 feet, and zones (5). This region has a greater diversity of forest plant the mean annual precipitation is about 24 to 35 inches. communities that grow in a more complex pattern than any The vegetation in this zone is mainly Douglas fir and comparable area in the western part of the United States ponderosa pine. Pacific madrone and California black oak (31). are common. Interspersed throughout the zone are shallow, The major regional climatic variations within the survey droughty, or clayey soils that support grasses, shrubs, or area extend both from north to south and from east to mixed stands of oak and ponderosa pine. Hot, dry west. These variations, as influenced by the geologic and summers, which are typical in this zone, contribute to long topographic variations typical of the area, result in unique periods of high moisture stress and to the mortality of tree soil-vegetation relationships. The characteristics of the seedlings (28). vegetative sites identified in this survey area reflect variations in climate, geology, and topography. Vegetative zone 3. This zone includes general soil The vegetative sites occur on the landscape in map units 6, 19, and 21. It is at low elevations on combinations and positions that are predictable and are mountains. Elevation typically is less than 4,000 feet, and repeated throughout a given area of similar soils and the mean annual precipitation is about 35 to 50 inches. macroclimate. Geographic areas that have a significantly The vegetation in this zone is dominated by Douglas fir different macroclimate represent different vegetative zones and a complex, diverse understory. California black oak, that are made up of different vegetative sites or different Pacific madrone, canyon live oak, and sugar pine are combinations of sites. Consequently, soil-vegetation common in much of the zone. White fir is of minor extent or relationships within the survey area are much better does not occur in most stands. It is more common on understood if they are related to the major geographic north-facing slopes at elevations of about 3,000 feet than in areas. other areas. Vegetative Zones Vegetative zone 4. This zone includes general soil This section describes the vegetative zones in the map units 7, 9, and 18. It is in the most moist geographic survey area and identifies the general soil map units that area. Such species as Pacific are included in each zone. rhododendron, salal, red huckleberry, red alder, and dominated by pure stands of white fir on north-facing slopes western hemlock are characteristic of this zone. The and in nearly level areas. White fir, Douglas fir, and incense mean annual precipitation is about 40 to 60 inches. cedar grow on south-facing slopes. Understory species are The vegetation in this zone is dominated by Douglas fir. few and are sparsely distributed. White pine and Shasta red The understory is characterized by a dense cover of salal fir, which commonly grow on cold sites at high elevations, and western swordfern. Areas on north-facing slopes and are not evident. along drainageways support a small amount of western The second climatic area includes general soil map units hemlock. 14 and 17. The vegetative sites in this area are dominated by stands of white fir and Douglas fir. The sites are Vegetative zone 5. This zone includes general soil map interspersed with meadows and stands of lodgepole pine in units 8, 10, 22, and 23. It is at low elevations in the cold depressions. Also, they support an abundance of Cascade Mountains. The mean annual precipitation is Pacific yew and stunted chinkapin and sporadic white pine about 35 to 50 inches. and Shasta red fir. This area has gained attention in recent The vegetation in this zone is dominated by white fir decades as a major problem area for tree regeneration and and Douglas fir. Ponderosa pine, sugar pine, California forest management (12). black oak, and Pacific madrone are important species. The third climatic area in this zone includes general soil Small meadows in areas of poorly drained soils are map unit 15. The vegetative sites in this area are interspersed throughout this zone. dominated by white fir or Shasta red fir, or both, and varying amounts of white pine. Douglas fir is common only Vegetative zone 6. This zone includes general soil map on south-facing slopes, and the growth of ponderosa pine units 24 and 25. It supports plants that are transitional is sporadic. The area is interspersed with meadows and between those of the forest communities on the western lodgepole pine in cold depressions. Understory species flank of the Cascade Mountains and those of the plant are numerous and are abundant. communities in the central part of Oregon. The mean annual precipitation is about 25 to 35 inches. Winters are Vegetative Sites cold. This section describes the vegetative sites in the The main vegetation in this zone is a mixed conifer forest survey area. The descriptions specify the potential natural characterized by ponderosa pine, sugar pine, incense plant community for each site, the variations in plant cedar, Douglas fir, and white fir interspersed with small growth and species on the site, associated sites, and ponderosa pine forests, juniper scabland, sagebrush flats, management of the site and its response to disturbance. and meadows. The plant communities associated with this zone include fewer understory species than those on the Biscuit-Scabland (intermound), 18- to 26-inch western flank of the Cascade Mountains. precipitation zone. The potential plant community on this site is dominated by forbs and grasses, such as annual Vegetative zone 7. This zone includes general soil hairgrass, Canada bluegrass, spikerush, mouse barley, map units 12 and 26. It is along the watershed of the and Pacific foxtail. Forbs include bicolor lupine, dowingia, Klamath River, near the California-Oregon State line. This poverty clover, tomcat clover, nakedstem broomrape, zone is on the low-elevation edge of the Cascade wooly meadowfoam, and brodiaea. Mountains. The climate and plant communities are Site variation.-Plant growth and the kind of species vary transitional to those east of those mountains. considerably from place to place, depending on the degree The species that commonly grow farther east in Oregon, of wetness and the soil depth. such as antelope bitterbrush, rabbitbrush, and western Associated sites.-The site Biscuit-Scabland (mound), juniper, are abundant in this zone. Noticeably absent from 18- to 26-inch precipitation zone, is on mounds in areas of the plant communities are plants that are common to the patterned ground. Areas of the deeper soils include the western part of Oregon, such as Pacific madrone, whiteleaf sites Loamy Shrub Scabland, 18- to 35-inch precipitation manzanita, and poison oak. zone; Loamy Hills, 20- to 35-inch precipitation zone; and Droughty Slopes, 20- to 30-inch precipitation zone. Vegetative zone 8. This zone is in the summit area of Management and response to disturbance.-The the southern extension of the Cascade Mountains. It more palatable forage plants include Canada bluegrass, consists of three distinct climatic areas that are typical of annual hairgrass, and mouse barley, but these plants cold, high-elevation snow zones. commonly are sparse or do not grow in all areas of the The first of these climatic areas includes general soil map unit 16. The vegetative sites in this area are site. The annual grasses and forbs that invade the site bluegrass, pine bluegrass, prairie junegrass, California include soft chess, medusahead wildrye, hedgehog dogtail, brome, and blue wildrye. Forbs include western buttercup, and tarweed. Livestock grazing is minimal on this site. carrotleaved horkelia, western yarrow, brodiaea, yampa, Grazing management decisions normally are the same as and fawnlily. those for the adjacent mound areas, which are the primary Site variation.-Concave areas and areas near grazing areas. drainageways support more Canada bluegrass and may support less Oregon white oak. Areas on north-facing Biscuit-Scabland (mound), 18- to 26-inch slopes and areas that receive a greater amount of precipitation zone. The potential plant community on this precipitation commonly support much more ponderosa pine site is dominated by bluebunch wheatgrass. Other and California black oak and less Oregon white oak. grasses include Lemmon needlegrass, pine bluegrass, Associated sites.-The site Loamy Shrub Scabland, 18- Idaho fescue, and California brome. Wedgeleaf ceanothus to 35-inch precipitation zone, is in areas where soil depth is is the only shrub that is potentially of significant extent. It limited. The sites Douglas Fir Forest and Pine-Douglas may be included on the site in response to fires in the Fir-Fescue are in areas where the Clayey Hills site is past. Forbs include lomatium, wooly eriophyllum, bicolor adjacent to timbered areas. The sites Loamy Hills, 20- to lupine, western buttercup, western yarrow, woodlandstar, 35-inch precipitation zone, and Droughty North, 18- to and purplehead brodioea. 35-inch precipitation zone, are in some areas. Site variation.-Western juniper occasionally grows in the Management and response to disturbance.-The more drainage area of the Klamath River. palatable forage plants include California oatgrass, Idaho Associated sites.-The site Biscuit-Scabland fescue, Canada bluegrass, and pine bluegrass. Overgrazing (intermound), 18- to 26-inch precipitation zone, is in areas results in a decrease in the abundance of the more where soil depth is limited. The site Loamy Hills, 20- to preferred forage species, which gradually are replaced by 35-inch precipitation zone, is in some areas. The site native forbs and invader grasses and forbs. The dominant Poorly Drained Bottom is in basins, in drainageways, and invader grasses include medusahead wildrye, ripgut brome, between mounds in areas of patterned ground in the valley sterile brome, hedgehog dogtail, and wild oat. The forbs that of Bear Creek. The site Droughty Fan, 18- to 26-inch invade include starthistle, prickly lettuce, Klamath weed, precipitation zone, is in areas where the soils are clayey. fiddleneck, and tarweed. Poison oak moderately increases The sites Droughty Slopes, 20- to 30-inch precipitation in abundance following a disturbance or decline in the zone, and Loamy Shrub Scabland, 18- to 35-inch ecological condition. If the oak is cut or burned, it will sprout precipitation zone, are in the drainage areas of the Klamath and become reestablished on the site. River where the soils are clayey or soil depth is limited. Management and response to disturbance.-The more Claypan, 14- to 18-inch precipitation zone. The palatable forage plants include bluebunch wheatgrass, potential plant community of this site is dominated by Lemmon needlegrass, pine bluegrass, and Idaho fescue. Idaho fescue and low sagebrush. Sandberg bluegrass Overgrazing results in a decrease in the abundance of the and bluebunch wheatgrass and minor amounts of prairie more palatable forage plants and an increase in the junegrass, Thurber needlegrass, bottlebrush squirreltail, abundance of annual grasses and forbs. Annual grasses and sedge also grow on the site. Forbs include wooly include annual fescue, soft chess, medusahead wildrye, eriophyllum, shrubby buckwheat, snow eriogonum, clover, ripgut brome, and cheatgrass. Common forbs that increase phlox, and yampa. Shrubs include not only low sagebrush in abundance or invade are filaree, bicolor lupine, but also antelope bitterbrush. popcornflower, lomatium, and cornsalad. Range seeding is Site variation.-In some areas scattered western impractical in most places because of the many intermound juniper or ponderosa pine grow on this site. areas, which restrict the movement of ground equipment. Associated sites. The sites Intermittent Swale and Loamy Juniper Scabland, 20- to 30-inch precipitation Clayey Hills, 20- to 35-inch precipitation zone. The zone, are in some areas. The sites Douglas Fir-Mixed potential plant community of this site is dominated by Pine-Sedge Forest and Ponderosa Pine-Fescue are in Oregon white oak and scattered ponderosa pine and areas adjacent to forest land. California black oak. Shrubs include Pacific serviceberry, Management and response to disturbance.-The poison oak, and hairy honeysuckle. The understory is more palatable forage plants include Idaho fescue, dominated by a dense stand of California oatgrass. Other grasses include Idaho fescue, Canada bluebunch wheatgrass, and Sandberg bluegrass. Deep Loamy Terrace, 18- to 28-inch precipitation Overgrazing results in a decrease in the abundance of zone. The potential plant community on this site is Idaho fescue and bluebunch wheatgrass and an increase dominated by ponderosa pine, California black oak, Oregon in the abundance of Sandberg bluegrass and bottlebrush white oak, and Pacific madrone. Small amounts of incense squirreltail. Annual grasses and forbs, such as cheatgrass, cedar and Douglas fir are in some areas. Understory annual brome, knotweed, birdbeak, and hemizonia, invade shrubs include an abundance of common snowberry. They areas where the site has deteriorated. also include Pacific serviceberry, tall Oregongrape, poison oak, creambush oceanspray, and hairy honeysuckle. Deep Loamy, 16- to 20-inch precipitation zone. The Grasses are sparse. They include Idaho fescue, California potential plant community on this site is dominated by brome, blue wildrye, and pine bluegrass. Forbs include ponderosa pine, which commonly regenerates in clumps giant fawnlily, beauty cinquefoil, mountain sweetroot, and under openings in the canopy. The dominant understory horsetail, and lupine. shrub is antelope bitterbrush, but the site supports minor Site variation.-Some nearly level areas near amounts of Pacific serviceberry, big sagebrush, desert drainageways support Oregon ash and black hawthorn. gooseberry, green rabbitbrush, and Klamath plum. Grasses Associated sites. The site Loamy Flood Plain, 18- to and grasslike plants are dominated by Idaho fescue but 30-inch precipitation zone, is in areas near drainageways include bluebunch wheatgrass, Sandberg bluegrass, Ross that are subject to flooding. The site Poorly Drained Bottom sedge, prairie junegrass, and western needlegrass. Forbs also is in areas near drainageways. The site Pine-Douglas include western yarrow, pearly everlasting, wooly Fir-Fescue is on alluvial fans and in upland areas where the eriophyllum, lomatium, lupine, and arrowleaf balsamroot. soils are well drained. The sites Loamy Hills, 20- to 35-inch Associated sites.-The sites Mixed Conifer- precipitation zone, and Loamy Slopes, 18- to 24-inch Chinkapin-Sedge Forest and Mixed Conifer-Bitterbrush- precipitation zone, are in upland areas where the soils are Sedge Forest are in areas that are colder and receive a well drained and soil depth is limited. greater amount of precipitation. The site Ponderosa Management and response to disturbance.-The Pine-Fescue is in areas that receive a greater amount of more palatable forage grasses include Idaho fescue, pine precipitation. The site Wet Meadow is in basins and near bluegrass, and California brome. Many areas have been drainageways. cleared and are used for crop production. Overgrazing Management and response to disturbance. The more results in a decrease in the abundance of the more palatable forage plants include Idaho fescue, Ross sedge, palatable forage plants but has little effect on the total plant bluebunch wheatgrass, and western needlegrass. If the site composition. Competition for light is the dominant factor is grazed in the fall, they also include antelope bitterbrush. affecting adjustments in the understory cover in areas that Overgrazing for prolonged periods results in a decrease in are grazed. the abundance of Idaho fescue, bluebunch wheatgrass, and Light removal of ponderosa pine permits the hardwood antelope bitterbrush and can hinder tree reproduction. overstory to expand and the understory grasses Needlegrass, squirreltail, big sagebrush, and green temporarily to increase in abundance. Complete removal of rabbitbrush may increase in abundance where lighting is the overstory results in expansion of the herbaceous cover adequate. Changes in plant composition generally are and vigorous sprouting of oak and madrone. Ponderosa influenced by surface disturbance, canopy removal, and pine may regenerate, particularly in areas where there has competition among species for moisture and light. been some burning or surface disturbance. Severe Ground fires or logging can increase the potential for disturbance of the surface or burning results in the invasion grass production, temporarily reduce the abundance of of whiteleaf manzanita and Kentucky bluegrass and the antelope bitterbrush, and thin out young stands of pine. If vigorous sprouting of hardwood trees. Blackberry also may openings are created in the canopy, grasses and antelope invade the site. bitterbrush can become more abundant in response to the increased amount of light. Pine regenerates in new Douglas Fir Forest. The potential plant community on openings after burning and in some areas forms dense, this site is dominated by Douglas fir. Some areas support stagnated stands that require thinning. As the overstory small amounts of other coniferous trees, including incense closes, the increased shade thins out light -dependent cedar, ponderosa pine, and sugar pine. Hardwoods are grasses and greatly reduces the abundance of antelope common in the overstory. They include Pacific madrone bitterbrush. and California black oak. The midstory is dominated by trees and tall shrubs, such as creambush oceanspray, Pacific serviceberry, California hazel, and deerbrush. Understory shrubs include common Jeffrey pine. In a few areas, they also include Pacific yew. snowberry, poison oak, tall Oregongrape, trailing Pacific madrone is the most common overstory hardwood; blackberry, baldhip rose, thimbleberry, and hairy however, golden chinkapin is in some stands. The honeysuckle. Important species in the grass cover, which is understory commonly includes shrub-sized canyon live oak sparse, include western fescue, mountain brome, tall and shrubs, such as creambush oceanspray, woodland trisetum, and blue wildrye. Forbs include starflower, phlox, baldhip rose, cascade Oregongrape, Whipplevine, strawberry, western swordfern, Hooker fairybells, California and pinemat manzanita. Grasses and grasslike plants vetch, white hawkweed, and tarweed. include California fescue , western fescue, Alaska Site variation.-Canyon live oak commonly grows in areas oniongrass, crinkleawn fescue: and common beargrass. of this site in the western part of the survey area. Sugar pine Forbs include Henderson fawnlily, Nuttal peavine, white commonly grows in areas where the soils formed in material hawkweed, spring queen, hillside reinorchid, western derived from granitic rock. In the Siskiyou Mountains, onsite swordfern, and Indian dream fern. investigation may be needed to distinguish this site from the Site variation.-Areas on south-facing slopes support a sites Loamy Hills, 20- to 35-inch precipitation zone, and more open overstory and a greater abundance of Droughty North, 18- to 35-inch prec ipitation zone. understory species, such as common beargrass, California Associated sites.-The site Droughty North, 18- to 35-inch fescue, and canyon live oak. Jeffrey pine grows mainly on precipitation zone, is in some areas. The site Pine-Douglas south-facing slopes. Fir-Fescue is in nearly level areas and on south-facing Associated sites.-The site Mixed Fir-Salal slopes. The site Mixed Pine-Douglas Fir-Fescue Forest, (rhododendron) Forest is in areas on north-facing slopes Granitic, is in areas of soils that formed in material derived where the soils are not influenced by serpentine. The site from granite. It is in nearly level areas and on south-facing Douglas Fir-Madrone-Chinkapin Forest is in areas on slopes. south-facing slopes where the soils are not influenced by Management and response to disturbance.-The more serpentine. palatable forage plants include western fescue, mountain Management and response to disturbance.-The more brome, tall trisetum, creambush oceanspray, deerbrush, palatable forage plants include western fescue, Alaska and Pacific serviceberry. oniongrass, crinkleawn fescue, and creambush Clearcutting or severe burning results in the oceanspray. Logging or burning generally results in an development of dense stands of brush that are dominated increase in the abundance of low-value, unpalatable by deer brush and whiteleaf manzanita and by sprouted species, such as California fescue, common beargrass, Pacific madrone and California black oak. Other aggressive Whipplevine, canyon live oak, and greenleaf manzanita. shrubs include Pacific serviceberry, tall Oregongrape, Brush fields may be dense enough to restrict access by common snowberry, poison oak, and hairy honeysuckle. livestock. Where there is no Douglas fir overstory, most of the Heavy logging or burning results in an increase in the grasses and forbs that require much light increase abundance of sprouting shrubs and trees, such as Pacific considerably in abundance and ponderosa pine is most madrone and canyon live oak, and in some regeneration of likely to regenerate. incense cedar and Jeffrey pine. Other species that rapidly The hardwoods eventually form a canopy that dominates increase in abundance under such conditions include the brush fields. As new stands develop, however, the common beargrass, western fescue, creambush hardwoods and the brush fields are suppressed and then oceanspray, Whipplevine, greenleaf manzanita, and white are overtopped by the conifers. A dense overstory of hawkweed. pole-sized Douglas fir commonly develops. The dense overstory reduces the abundance of Pacific madrone and Douglas Fir-Black Oak Forest. The potential plant oak and drastically reduces the abundance of understory community on this site is dominated by Douglas fir. species. As the stand matures or after selective logging, the Ponderosa pine and sugar pine are common in the understory increases in abundance in response to the overstory. Incense cedar grows only in some areas. The increased penetration of light through the canopy. prominent overstory hardwood trees include California black oak and Pacific madrone. The understory includes scattered Douglas Fir-Beargrass Forest, Serpentine. The canyon live oak and a few stunted white fir and golden potential plant community on this site is dominated by chinkapin. Understory shrubs include deerbrush, creambush Douglas fir and lesser amounts of incense cedar. Other oceanspray, California hazel, common snowberry, tall less common coniferous trees include sugar pine, and Oregongrape, and western princes pine. Grasses include western fescue, mountain brome, California fescue, and crinkleawn fescue. Forbs include iris, strawberry, brackenfern, white hawkweed, at an elevation of more than 3,000 feet or that receive a and tarweed. greater amount of precipitation. Site variation.-Tanoak and evergreen huckleberry Associated sites. -The site Douglas Fir-Black Oak grow in some areas of this site in the western part of the Forest is on south-facing slopes. The site Douglas Fir-Pine survey area. Canyon live oak generally does not grow in Forest, Serpentine, is in areas that are influenced by the eastern part of this site's range. serpentine. Associated sites.-The site Douglas Fir-Chinkapin Forest Management and response to disturbance.-The is on north-facing slopes. The site Douglas Fir-Pine more palatable forage plants include western fescue, Forest, Serpentine, is in areas that are influenced by mountain brome, Alaska oniongrass, crinkleawn fescue, serpentine. and deerbrush. Forage production in typical middle-aged or Management and response to disturbance.-The old-growth stands is moderate or low in all areas, except for more palatable forage plants include western fescue, openings that receive much light. mountain brome, crinkleawn fescue, and deerbrush. Clearcutting or burning generally is followed by the Grazing pressure is greatest in the open areas, where development of dense stands of shrubs, such as these plants are most common. deerbrush, California hazel, creambush oceanspray, Clearcutting or burning usually is followed by the common snowberry, Whipplevine, hairy manzanita, and development of dense stands of shrubs, such as deerbrush, poison oak. Sprouting hardwood trees recover rapidly. As a creambush oceanspray, common snowberry, Whipplevine, result, Pacific madrone, California black oak, and golden California hazel, hairy honeysuckle, poison oak, tall chinkapin can dominate new stands. Ponderosa pine Oregongrape, and hoary manzanita. Sprouting hardwood generally regenerates only in minor amounts, but trees recover rapidly. As a result, Pacific madrone and regeneration is most likely at this early stage, when the California black oak can dominate new stands. Ponderosa maximum amount of light is available. Douglas fir pine regenerates most readily at this early stage of regenerates slowly, but it eventually emerges through the succession, when more light is available. Douglas fir canopy of shrubs and hardwood trees and regains regenerates slowly, but it eventually emerges through the dominance of the site. canopy of shrubs and hardwood trees and regains Selective logging or local disturbances in normal stands dominance of the site. permit suppressed species to grow as more light becomes Selective logging, the less severe burns, or local available. The species that have low tolerance to light, such disturbances result in varied plant responses, depending as deerfoot vanillaleaf, may decrease in abundance. on the species removed, the degree of cutting or burning, and the extent of surface disturbance. As more light Douglas Fir-Dogwood Forest, Granitic. The potential becomes available, suppressed understory plants begin plant community on this site is dominated by Douglas fir and to grow and such species as ponderosa pine, deerbrush, some sugar pine. Other coniferous trees, which occur in common snowberry, and most grasses increase in small amounts, include incense cedar and ponderosa pine. abundance. Common overstory hardwoods include Pacific madrone and California black oak. The midstory includes regenerated Douglas Fir-Chinkapin Forest. The potential plant conifers and Pacific dogwood. Understory shrubs include community on this site is dominated by Douglas fir and creambush oceanspray, California hazel, common minor amounts of other conifers, such as sugar pine, snowberry, poison oak, baldhip rose, deerbrush, and hairy ponderosa pine, and incense cedar. In addition to golden honeysuckle. Grasses include western fescue, mountain chinkapin, the hardwood trees on this site include Pacific brome, and California fescue. Forbs, which are sparse, madrone, California black oak, Pacific dogwood, and include tarweed, starflower, California bellflower, canyon live oak. Understory shrubs include cascade brackenfern, white hawkweed, western swordfern, and Oregongrape, Whipplevine, western princes pine, American mountain sweetroot. twinflower, California hazel, and creambush oceanspray. Site variation.-Some areas at the higher elevations and The grass cover, which is sparse, includes western fescue, areas where more moisture is available support scattered mountain brome, Alaska oniongrass, and crinkleawn white fir, golden chinkapin, cascade Oregongrape, fescue. Common forbs include deerfoot vanillaleaf, deerfoot vanillaleaf, common beargrass, arnica, and insideout flower, brackenfern, and white hawkweed. American twinflower. Site variation.-Canyon live oak commonly does not Associated sites.-The site Douglas Fir-Black Oak grow in most areas in the eastern part of this site's range. Forest is on south-facing slopes at elevations of less White fir and salai grow in some areas that are than 3,000 feet. The site Douglas Fir-Madrone- Chinkapin Forest is on south-facing slopes at elevations of that have been opened by disturbances, such as logging more than about 3,000 feet. The site Douglas Fir-Chinkapin and burning; however, some areas that have been heavily Forest is in areas on north-facing slopes where the soils did thinned or clearcut support an abundance of unpalatable not form in material derived from granite. . evergreen species, such as Pacific madrone, cascade Management and response to disturbance.-The Oregongrape, snowbrush, manzanita, and golden more palatable forage plants include mountain brome, chinkapin. These brush fields may be dense enough to western fescue, and deerbrush. Because of a high hazard restrict access by livestock. Because of a high hazard of of erosion on the soils in areas of this site, the steeper erosion on the soils in areas of this site, which formed in slopes should not be grazed. material derived from granitic rock or schist, the steeper Clearcutting or burning results in the development of slopes should not be grazed. dense stands of brush, such as sprouted Pacific madrone Clearcutting or burning results in the development of and California black oak, and shrubs, such as deerbrush, dense stands of brush that include native shrubs, such as creambush oceanspray, whiteleaf manzanita, common creambush oceanspray, California hazel, common snowberry, thimbleberry, and poison oak. Grasses and snowberry, baldhip rose, trailing blackberry, and forbs that require much light become more abundant in Whipplevine. Invaders, such as snowbrush, hoary open areas created by logging and burning. Ponderosa manzanita, and greenleaf manzanita, are common in some pine is most likely to regenerate when there is less conifer areas. Pacific madrone and golden chinkapin sprout rapidly overstory and more available light. Later, as the new stand and compete well with the shrubs. In addition to shrubs, develops, hardwood trees and shrubs are overtopped and some grasses and light -tolerant forbs become more suppressed by Douglas fir. As the stand matures or after abundant in open areas. selective logging, the understory composition gradually changes in response to significant changes in light Douglas Fir-Mixed Pine -Fescue Forest. The potential intensity. plant community on this site is dominated by Douglas fir. Sugar pine is abundant, and some ponderosa pine and Douglas Fir-Madrone-Chinkapin Forest. The potential incense cedar are in the stands. Common hardwood trees plant community on this site is dominated by Douglas fir and in the overstory are Pacific madrone and California black some white fir and incense cedar. Small amounts of sugar oak. The midstory is characterized by regenerated trees pine and western hemlock are in some areas. The main and tall shrubs, such as deerbrush, creambush hardwood trees in the overstory are Pacific madrone and oceanspray, Pacific serviceberry, and California hazel. minor amounts of golden chinkapin and Pacific dogwood. Understory shrubs include common snowberry, poison Common understory shrubs are cascade Oregongrape, oak, wild rose, tall Oregongrape, Whipplevine, western common snowberry, baldhip rose, California hazel, princes pine, and hairy honeysuckle. Grasses include creambush oceanspray, western princes pine, trailing western fescue, blue wildrye, mountain brome, tall blackberry, Whipplevine, and American twinflower. The trisetum, and California fescue. Forbs include California grass cover, which is sparse, includes western fescue, vetch, brackenfern, Henderson fawnlily, California tea, mountain brome; and crinkleawn fescue. The prominent strawberry, California bellflower, white hawkweed, and forbs include brackenfern, strawberry, deerfoot vanillaleaf, Hooker fairybells. starflower, mountain sweetroot, western swordfern, and Site variation.-Canyon live oak grows in some areas of white hawkweed. this site in the western part of the survey area. Areas where Associated sites.-The site Mixed Fir-Salal the amount of precipitation is lowest, such as those along (rhododendron) Forest is on north-facing slopes and in the Applegate River and its tributaries, support stands that concave areas. The site Douglas Fir-Black Oak Forest is in are dominated by ponderosa pine or Oregon white oak. areas that receive a smaller amount of precipitation and at Associated sites. The site Pine-Douglas Fir-Fescue is on elevations of more than about 3,000 feet. The sites Douglas south-facing slopes. The site Douglas Fir Forest is on Fir-Beargrass Forest, Serpentine, and Douglas Fir-Pine north-facing slopes. The site Droughty North, 18- to 35-inch Forest, Serpentine, are in areas where the soils are precipitation zone, is in some areas. influenced by serpentine. Management and response to disturbance.-The Management and response to disturbance.-The more palatable forage plants include mountain brome, tall more palatable forage plants include western fescue, trisetum, western fescue, and deerbrush. Because of a high mountain brome, Alaska oniongrass, and creambush hazard of erosion on the soils in areas of this site, which oceanspray. The amount of forage is greater in areas formed in material derived from granitic rock, the steeper slopes should not be grazed. Management and response to disturbance. The more Clearcutting or burning results in the development of palatable forage plants include western fescue, dense stands of brush dominated by deerbrush, whiteleaf mountain brome, Orcutt brome, and tall trisetum and manzanita and by Pacific madrone and California black shrubs, such as deerbrush and Pacific serviceberry. oak. Other shrubs include Pacific serviceberry, Clearcutting or burning of the overstory results in the Whipplevine, tall Oregongrape, common snowberry, poison development of dense stands of brush, such as deerbrush, oak, and hairy honeysuckle. Most of the native grasses common snowberry, and Pacific serviceberry. Invading and forbs that require much light increase considerably in shrubs, such as greenleaf manzanita, snowbrush, and abundance. Ponderosa pine is most likely to regenerate wedgeleaf ceanothus, also grow in these brush fields. during periods when there is no Douglas fir overstory. Snowbrush is likely to grow only in the colder areas and Eventually, hardwoods form a canopy that dominates wedgeleaf ceanothus only in the warmer areas. the brush fields. As the new stand develops, however, the Regeneration of ponderosa pine and incense cedar results hardwoods and brush fields are suppressed and then are from logging or other disturbances that open the canopy. overtopped by conifers. A dense overstory of pole-sized California black oak regenerates by sprouting soon after Douglas fir generally develops. The dense overstory logging or burning. reduces the abundance of the Pacific madrone and oak Few herbaceous species invade the site following cover and drastically reduces the abundance of understory minor disturbances. After major surface disturbances, species. Later, as the stand matures or after selective such species as cheatgrass, bottlebrush squirreltail, logging, the understory expands in response to the tarweed, and thistle may invade the site. increased amount of light penetrating the canopy. Douglas Fir-Pine Forest, Serpentine. The potential Douglas Fir-Mixed Pine -Sedge Forest. The potential plant community on this site is dominated by Douglas fir and plant community on this site is dominated by Douglas fir. some incense cedar, Jeffrey pine, and sugar pine. The Other conifers, such as ponderosa pine, sugar pine, and hardwoods on the site include Pacific madrone in the incense cedar, are less common but grow in nearly all overstory and canyon live oak in the midstory. Understory areas. California black oak is the most common hardwood, shrubs, which are of minor extent, include creambush but it does not grow in all stands. White fir, Oregon white oceanspray, California hazel, common snowberry, oak, and western juniper grow only in a few stands. Whipplevine, tall Oregongrape, and hairy honeysuckle. Understory shrubs include deerbrush, common snowberry, Grasses include California fescue, western fescue, Pacific serviceberry, tall Oregongrape, wild rose, California brome, and prairie junegrass. Forbs include pachystima, squawcarpet, and western princes pine. western swordfern, Indian dream fern, iris, starflower, Nuttal Grasses include western fescue, tall trisetum, mountain peavine, and Henderson fawnlily. brome, Orcutt brome, and Ross sedge. Forbs include white Associated sites.-This site is adjacent to the sites hawkweed, starflower, spreading dogbane, and California Douglas Fir-Chinkapin Forest; Douglas Fir-Black Oak vetch. Forest; Mixed Fir-Salal (rhododendron) Forest; Douglas Site variation.-Such species as California black oak, Fir-Beargrass Forest, Serpentine; and Douglas Fir- Oregon white oak, western juniper, ponderosa pine, and Madrone-Chinkapin Forest. The site Shallow Serpentine, 30- incense cedar are more abundant in areas that receive a to 40-inch precipitation zone, is in areas where the soils are smaller amount of precipitation and are warmer. influenced by serpentine and soil depth is limited. Associated sites.-The sites Loamy Slopes, 18- to 24-inch Management and response to disturbance.-The precipitation zone, and Loamy Juniper Scabland, 20- to more palatable forage plants include western fescue, 30-inch precipitation zone, are in areas where soil depth is California brome, and prairie junegrass. Logging or burning limited. The site Mixed Conifer-Chinkapin-Sedge Forest is in generally results in stands of brush that include areas that receive a greater amount of precipitation and are Whipplevine, creambush oceanspray, California hazel, and colder. The sites Droughty Slopes, 20- to 30-inch common snowberry. The shrubs that invade the site include precipitation zone, and Loamy Shrub Scabland, 18- to hairy manzanita, greenleaf manzanita, and whiteleaf 35-inch precipitation zone, are in areas of soils that receive manzanita. They also include wedgeleaf ceanothus. a smaller amount of precipitation, are warmer, and have a Burning is followed by the sprouting of Pacific madrone and limited depth. The site Wet Meadow is in basins and near canyon live oak. drainageways. Droughty Fan, 18- to 26-inch precipitation zone. The potential plant community on this site is dominated by stands of Oregon white oak. California black oak grows in some areas. In places it is nearly codominant with and California goldpoppy. Oregon white oak grows only in a white oak. Ponderosa pine grows in some areas. Shrubs, few areas. which are sparse, include poison oak, Pacific serviceberry, Associated sites.-The site Droughty North, 18- to 35-inch and hairy honeysuckle. Idaho fescue may be codominant precipitation zone, is on north-facing slopes. The site Droughty with bluebunch wheatgrass and California brome in the Fan, 18- to 26-inch precipitation zone, is in the less sloping understory. Other grasses include blue wildrye, prairie areas. The sites Loamy Slopes, 18- to 24-inch precipitation junegrass, pine- bluegrass, and Lemmon needlegrass. zone, and Loamy Hills, 20- to 35-inch precipitation zone, are in Forbs include lomatium, wooly eriophyllum, carrotleaved areas where the soils have a limited depth and are not clayey. horkelia, western buttercup, and yampa. The site Clayey Hills, 20- to 35-inc h precipitation zone, is in Site variation. The abundance of California black oak is concave areas and in areas that receive a greater amount of greater in areas that receive a greater amount of precipitation. precipitation or where the soils are deeper. Management and response to disturbance. The more Associated sites. The site Droughty Foothill Slopes, 18- palatable forage plants include bluebunch wheatgrass, to 22-inch precipitation zone, is on the steeper slopes. The Lemmon needlegrass, California brome, pine bluegrass, and site Semi-Wet Meadow is in areas of poorly drained soils. Idaho fescue. Grazing by livestock in summer is limited The site Poorly Drained Bottom is in areas of poorly drained because the temperatures usually are very warm. Most areas soils near drainageways. The sites Clayey Hills, 20- to are dominated by annual grasses and forbs. Overgrazing 35-inch precipitation zone, and Droughty North, 18- to results in a decrease in the abundance of the more palatable 35-inch precipitation zone, are in the areas that receive-the perennial grasses and an increase in the abundance of poison most precipitation. The sites Loamy Hills, 20- to 35-inch oak and annual grasses, such as medusahead wildrye, soft precipitation zone, and Loamy Slopes, 18- to 24-inch brome, cheatgrass, and hedgehog dogtail. Forbs, such as star precipitation zone, are in areas of well drained soils that are thistle, filaree, willowweed, moth mullein, and tarweed, invade not clayey. areas where the site is in poor condition. Success in reseeding Management and response to disturbance. The more these areas is limited by the hot, dry summers and severe palatable forage plants on this site include Idaho fescue, competition from annual weeds. bluebunch wheatgrass, California brome, and pine bluegrass; however, most areas are dominated by annual Droughty North, 18- to 35-inch precipitation zone. grasses and forbs. Overgrazing results in a decrease in the The potential plant community on this site is dominated by abundance of Idaho fescue and bluebunch wheatgrass. Oregon white oak and birchleaf mountainmahogany. Small California brome, Lemmon needlegrass, and blue wildrye amounts of California black oak, ponderosa pine, and Douglas are native perennial grasses that increase in abundance fir are in some areas. Shrubs, which are of minor extent, include when competition from other perennials is reduced. The Pacific serviceberry, tall Oregongrape, hairy honeysuckle, and annual grasses that invade deteriorated stands include poison oak. The understory is dominated by a dense stand of medusahead wildrye, hedgehog dogtail, soft brome, sterile grasses, mainly Idaho fescue. Other grasses include prairie brome, ripgut brome, wild oat, and foxtail fescue. Forbs that junegrass, California brome, pine bluegrass, and blue wildrye. invade deteriorated sites include star thistle, field Forbs include wooly eriophyllum, western yarrow, agoseris, hedge-parsley, tarweed, and willowweed. Poison oak brodiaea, and lomatium. invades under these conditions and in some areas Site variation.-Birch leaf mountainmahogany is more develops into dense brush fields. abundant than oak at the higher elevations. At elevations of Cutting or burning results in the sprouting of Oregon more than 3,500 feet, Oregon white oak is sparse or does not white oak and California black oak and the eventual return occur and the site is more commonly on south-facing slopes. of a deciduous tree canopy. Some areas along the Klamath River support western juniper. Poison oak does not grow in these areas, and whiteleaf Droughty Foothill Slopes, 18- to 22-inch manzanita does not invade or form brush fields following major precipitation zone. The potential plant community on this disturbances. In the Siskiyou Mountains, onsite investigation site is dominated by bluebunch wheatgrass and Lemmon may be needed to distinguish areas of this site from areas of needlegrass. Other grasses include California brome, pine the Douglas Fir Forest or Pine-Douglas Fir-Fescue sites. bluegrass, Idaho fescue, and prairie junegrass. Shrubs include Brewer lupine, northern buckwheat, and poison oak. Forbs include wooly eriophyllum, lomatium, woolyhead clover, hawksbeard, Associated sites.-The site Douglas Fir Forest is in areas areas where this site is east of the Klamath River. that receive a greater amount of precipitation or that are on Associated sites.-The site Douglas Fir-Mixed Pine-Sedge north-facing slopes. The sites Loamy Hills, 20- to 35-inch Forest is in areas where the soils are deeper or are lower in precipitation zone, and Pine-Douglas Fir-Fescue are on content of rock fragments. The sites Loamy Shrub south-facing slopes. The site Shallow Mountain Slopes, 22- Scabland, 18- to 35-inch precipitation zone, and to 30-inch precipitation zone, is on south-facing slopes Biscuit-Scabland (intermound), 18- to 26-inch precipitation where soil depth is limited. The site Droughty Foothill zone, are in areas where soil depth is limited. The sites Slopes, 18- to 22-inch precipitation zone, is in some areas. Biscuit-Scabland (mound), 18- to 26inch precipitation zone, Management and response to disturbance.-The more and Loamy Slopes, 18- to 24inch precipitation zone, are in palatable forage plants include Idaho fescue, pine some areas. bluegrass, prairie junegrass, and California brome. Management and response to disturbance. -The more Overgrazing results in a decrease in the abundance of palatable forage plants include Idaho fescue, bluebunch Idaho fescue and an increase in the abundance of blue wheatgrass, pine bluegrass, and prairie junegrass. If the wildrye, California brome, and Lemmon needlegrass. The site is grazed in the fall, they also include antelope annual grasses that invade the site include soft brome, bitterbrush. Overgrazing results in a decrease in the cheatgrass, sterile brome, ripgut brome, and Pacific fescue. abundance of Idaho fescue, bluebunch wheatgrass, and The native forbs that increase in abundance include wooly antelope bitterbrush. In some areas, Lemmon needlegrass, eriophyllum, western yarrow, and lomatium. The annual pine bluegrass, and bottlebrush squirreltail increase in forbs that readily invade the site include tarweed, western abundance and annual grasses and forbs, such as snake-root, and filaree. medusahead wildrye, cheatgrass, soft chess, tarweed, corn After severe burns, dense brush fields of whiteleaf salad, Knotweed, and willowweed, invade. manzanita, wedgeleaf ceanothus, and poison oak Fire normally stimulates the growth of perennial commonly develop. These brush fields suppress the bunchgrasses but results in a temporary decrease in the understory vegetation and limit access by livestock. abundance of antelope bitterbrush and western juniper Burning or cutting of the white oak overstory initiates and a probable increase in the abundance of wedgeleaf sprouting, which causes the oak to reoccupy the canopy. ceanothus. Oregon white oak sprouts and rapidly Birchleaf mountain mahogany does not sprout, and fire reoccupies the site. eliminates it from the site for many years. The potential for converting this site from brush to Intermittent Swale. The potential plant community on suitable forage species is high, but conversion commonly is this site is dominated by Nevada bluegrass. Other grasses limited by the slope. The slope interferes with the use of and grasslike plants include slender wheatgrass, meadow ground equipment for site preparation and seeding; barley, Canby bluegrass, and sedge. Except for an however, aerial broadcast seeding after burning or brush occasional rose, rabbitbrush, or low sagebrush, the primary removal commonly is feasible, even on the steep slopes. shrub is silver sagebrush. The site supports a variety of forbs, including mat muhly, penstemon, western yarrow, Droughty Slopes, 20- to 30-inch precipitation zone. yampa, cinquefoil, brodiaea, and pearly everlasting, but The potential plant community on this site is dominated by these are only a minor part of the total composition. Oregon white oak and scattered western juniper. Other Associated sites. The site Claypan, 14- to 18-inch trees, which occur in small amounts, include ponderosa precipitation zone, is in some areas. The site Loamy pine and California black oak. Shrubs include Pacific Juniper Scabland, 20- to 30-inch precipitation zone, is in serviceberry, wedgeleaf ceanothus, antelope bitterbrush, areas where soil depth is limited. The sites Douglas Klamath plum, shrubby buckwheat, and birchleaf Fir-Mixed Pine-Sedge Forest and Ponderosa Pine-Fescue mountainmahogany. Idaho fescue, bluebunch wheatgrass, are in areas adjacent to forested sites. and pine bluegrass are the most common grasses; Management and response to disturbance.-The however, small amounts of Lemmon needlegrass, prairie more palatable forage plants include Nevada bluegrass, junegrass, and bottlebrush squirreltail also are on the site. slender wheatgrass, meadow barley, and Canby bluegrass. Forbs include lomatium, wooly eriophyllum, western yarrow, Overgrazing results in a decrease in the abundance of the filaree, yampa, brodiaea, and collomia. more palatable perennial grasses and an increase in the Site variation.-Some of the less sloping areas and abundance of silver sagebrush. Annual forbs and grasses, some concave areas support California oatgrass and such as willowweed, tarweed, brome, medusahead wildrye, ponderosa pine. California black oak rarely grows in and squirreltail, invade the site under these conditions. When the site is in poor condition, much of the surface that was Lemmon needlegrass. Forbs include western buttercup, protected by a bluegrass cover becomes bare. wooly eriophyllum, Parry hawkweed, western yarrow, lomatium, and lupine. Loamy Flood Plain, 18- to 30-inch precipitation zone. Site variation.-California black oak and ponderosa pine The potential plant community on this site is dominated by are more abundant where this site is in the Cascade black cottonwood. Other trees in the overstory include Mountains than where it is in the Siskiyou Mountains. Oregon ash, bigleaf maple, white alder, willow, and Oregon Bluebunch wheatgrass becomes prominent in the more white oak. California black oak and ponderosa pine are droughty or exposed areas. In the Siskiyou Mountains, included in some areas. The understory consists of dense onsite investigation may be needed to distinguish areas of stands of wild grape, blackberry, creambush oceanspray, this site from areas of the Douglas Fir Forest or common snowberry, skunkbush sumac, Pacific Pine-Douglas Fir-Fescue site. serviceberry, mockorange, Klamath plum, and poison oak. Associated sites.-The site Loamy Shrub Scabland, 18- Various forbs, such as Spanish clover, mountain sweetroot, to 35-inch precipitation zone, is in areas where soil depth is curly dock, cinquefoil, nettle, and cowparsnip, grow in a few limited. The site Clayey Hills, 20- to 35-inch precipitation areas. They are most common beneath openings in the zone, is in concave areas in the Cascade Mountains. The canopy. site Douglas Fir Forest is on north-facing slopes in areas Site variation.-Black cottonwood and bigleaf maple are adjacent to timbered sites. The site Pine-Douglas less prominent in areas where the soils are more Fir-Fescue is in areas adjacent to timbered sites. The site droughty. Low areas in flood channels are likely to support Droughty North, 18- to 35-inch precipitation zone, is on an understory of grasses and water-tolerant species, such north-facing slopes. The site Biscuit-Scabland (mound), as rushes and sedges. 18- to 26-inch precipitation zone, is in areas of patterned Associated sites.-The site Deep Loamy Terrace, 18- to ground. 28-inch precipitation zone, is in areas that are not subject to Management and response to disturbance.-The flooding. more palatable forage plants include Idaho fescue, Management and response to disturbance.-The bluebunch wheatgrass, pine bluegrass, and California more palatable forage plants include oniongrass, sedge, and brome. Overgrazing results in a decrease in the abundance forbs, such as dandelion and clover. Willow, elderberry, and of the more palatable forage plants and an increase in the other shrubs provide some browse. Grazing is limited to the abundance of annual forbs and grasses. The prominent more open areas of this site because of the density of the grasses that invade include soft brome, ripgut brome, sterile understory. Excessive grazing pressure results in an brome, hedgehog dogtail, and medusahead wildrye. The increase in the abundance of the less palatable shrubs and forbs that invade include cleavers bedstraw, tarweed, herbaceous species, such as Nootka rose, Kentucky western snake-root, Klamath weed, and willowweed. bluegrass, sumac, and blackberry. Fire commonly is followed by an initial invasion of Areas where the hardwoods have been uprooted by wedgeleaf ceanothus, through which whiteleaf manzanita flooding or have deteriorated and have died may become emerges and eventually dominates the site. The result is a very dense with brush before trees are reestablished. dense stand of brush in which nearly all of the understory Flood-scoured areas and new deposits of sand and gravel grasses and forbs are eliminated. In many areas the stand become revegetated with shrubs, such as willow, of brush becomes a barrier to livestock movement. The blackberry, and sumac, or with herbaceous species if there site can be improved if the brush is removed and forage is adequate soil material and some protection from continual species are seeded. scouring is provided. Loamy Juniper Scabland, 20- to 30-inch precipitation Loamy Hills, 20- to 35-inch precipitation zone. The zone. The potential plant community on this site is potential plant community on this site is dominated by dominated by scattered western juniper, but an occasional Oregon white oak and varying amounts of California black Oregon white oak or ponderosa pine is included in some oak and ponderosa pine. Pacific madrone is included in areas. Shrubs include antelope bitterbrush, shrubby minor amounts. Shrubs, which are of minor extent, include buckwheat, and wedgeleaf ceanothus. Grasses include Pacific serviceberry, Klamath plum, birchleaf bluebunch wheatgrass, Sandberg bluegrass, pine mountainmahogany, and hairy honeysuckle. The bluegrass, Idaho fescue, Thurber needlegrass, and Lemmon understory is dominated by Idaho fescue. Other grasses needlegrass. Forbs include wooly eriophyllum, hawksbeard, include prairie junegrass, bluebunch wheatgrass, pine western yarrow, lomatium, and yampa. bluegrass, California brome, and Site variation.-Some areas of this site in the eastern part Management and response to disturbance.-The more of the survey area support low sagebrush and do not palatable forage plants include bluebunch wheatgrass, pine support Oregon white oak or wedgeleaf ceanothus. Areas bluegrass, Lemmon needlegrass, and Harford's melica. of this site commonly are adjacent to forested sites. They Some areas of this site are the first to be grazed in spring, support an occasional ponderosa pine or other conifer. but the forage can be grazed for only a short period. Associated sites.-Areas where the soils are deeper Overgrazing eventually depletes the perennial grass cover include the sites Droughty Slopes, 20- to 30-inch and increases the abundance of annual grasses and forbs. precipitation zone; Loamy Slopes, 18- to 24-inch precipitation zone; Douglas Fir-Mixed Pine-Sedge Forest; Loamy Slopes, 18- to 24-inch precipitation zone. and Ponderosa Pine-Fescue. The potential plant community on this site is dominated by Management and response to disturbance.-The more ponderosa pine. Oregon white oak, California black oak, palatable forage plants include bluebunch wheatgrass, and Pacific madrone also are common in the overstory. Idaho fescue, pine bluegrass, Sandberg bluegrass, and Shrubs include Pacific serviceberry, birchleaf antelope bitterbrush. Overgrazing for prolonged periods mountainmahogany, Klamath plum, deerbrush, common results in a decrease in the abundance of Idaho fescue and snowberry, tall Oregongrape, poison oak, and hairy bluebunch wheatgrass and an increase in the abundance of honeysuckle. Grasses include Idaho fescue, California native plants, such as bluegrass, bottlebrush squirreltail, brome, blue wildrye, and pine bluegrass. Forbs, which grow Lemmon needlegrass, and shrubby buckwheat. The plants only in small amounts, include wooly eriophyllum, Pacific that invade the site include cheatgrass, annual hairgrass, houndstongue, Parry hawkweed, mountain sweetroot, soft chess, medusahead wildrye, filaree, prickly lettuce, deltoid balsamroot, climbing bedstraw, and western fiddleneck, and knotweed. buttercup. Site variation.-Poison oak, hairy honeysuckle, Pacific Loamy Shrub Scabland, 18- to 35-inch precipitation madrone, and whiteleaf manzanita do not grow in the zone. The potential plant community on this site is drainage area of the Klamath River. dominated by an open stand of wedgeleaf ceanothus. Associated sites.-The site Douglas Fir-Mixed Pine-Sedge Other shrubs include poison oak and hairy honeysuckle. Forest is in the areas in the eastern part of the survey area An occasional Oregon white oak is included in some where the amount of precipitation is greater or the soils are areas. Grasses include bluebunch wheatgrass, pine deeper. The site Biscuit-Scabland (intermound), 18- to bluegrass, Lemmon needlegrass, squirreltail, and 26-inch precipitation zone, is in areas of the eastern part of Harford's melica. Forbs include coyote mint, wooly the survey area where soil depth is limited. The site eriophyllum, agoseris, and climbing bedstraw. Biscuit-Scabland (mound), 18to 26-inch precipitation zone, Site variation.-Areas of this site at an elevation of more is in some areas. The site Droughty Slopes, 20- to 30-inch than 3,500 feet in the Siskiyou Mountains support birchleaf precipitation zone, is in areas of range in the eastern part of mountainmahogany mixed with tall Oregongrape, bitter the survey area. The sites Droughty Fan, 18- to 26-inch cherry, and Klamath plum. They support little, if any, precipitation zone, and Droughty Foothill Slopes, 18- to wedgeleaf ceanothus; Harford's melica is much more 22-inch precipitation zone, are in areas where the soils are prominent. Areas of this site in the western part of the clayey. The site Loamy Hills, 20- to 35-inch precipitation survey area support canyon live oak and Fremont zone, is in some areas. silktassel. Some areas along the Klamath River support Management and response to disturbance.-The more antelope bitterbrush and western juniper and do not palatable forage plants include Idaho fescue, California support poison oak. brome, and pine bluegrass. Overgrazing results in a Associated sites.-The site Clayey Hills, 20- to 35inch decrease in the abundance of Idaho fescue and an precipitation zone, is in concave areas in the Cascade increase in the abundance of squirreltail, blue wildrye, and Mountains. The site Droughty Slopes, 20- to 30-inch other aggressive plants that increase in abundance in precipitation zone, is in the drainage area of the Klamath areas where they receive partial shade. River. The site Pine-Douglas Fir-Fescue is in areas Crown fire or overstory removal accompanied by adjacent to timbered sites. The site Douglas Fir Forest is on severe surface disturbance stimulates the growth of north-facing slopes adjacent to timbered sites. The site poison oak and causes the invasion of brush species, Loamy Hills, 20- to 35-inch precipitation zone, is in the such as whiteleaf manzanita and possibly wedgeleaf drainage area of the Rogue River. ceanothus. Oak and Pacific madrone sprout, thus creating brush stands that may persist for years. Ponderosa pine regenerates in some areas after the burning of the overstory or after logging, and it develops Douglas fir and white fir, but ponderosa pine, sugar pine, along with the brush. Where logging is not followed by the and incense cedar are important components of the natural regeneration of pine, the site may remain a brush overstory. In some areas California black oak also is field for many years. important. Various trees regenerate. Douglas fir and white fir are the most common regenerated species in highly Mixed Conifer-Bitterbrush-Sedge Forest. The shaded areas, especially on north-facing slopes. Understory potential plant community on this site is dominated by shrubs include common snowberry, baldhip rose, sierra Douglas fir and white fir, but ponderosa pine, sugar pine, chinkapin, tall Oregongrape, pachystima, squawcarpet, and and incense cedar also are important components of the western princes pine. Grasses, which are sparse, include overstory. Understory shrubs include common snowberry, western fescue, mountain brome, tall trisetum, Ross sedge, baldhip rose, sierra chinkapin, tall Oregongrape, and blue wildrye. Forbs include starflower, spreading pachystima, squawcarpet, western princes pine, and dogbane, western white anemone, western houndstongue, scattered antelope bitterbrush in openings that receive whitevein shinleaf, white hawkweed, and strawberry. more light. The grass cover, which is sparse, includes Site variation.-In areas where restricted air drainage western fescue, mountain brome, tall trisetum, Ross sedge, creates cold pockets, such as those in the basin of Johnson and blue wildrye. Forbs include starflower, spreading Prairie, this site supports lodgepole pine and does not dogbane, western white anemone, whitevein shinleaf, white support sugar pine or incense cedar. California black oak, hawkweed, and strawberry. deerbrush, thimbleberry, and a few other species common Site variation.-Lodgepole pine grows in areas where to the western slope of the Cascade Mountains grow only in restricted air drainage creates cold pockets. Sugar pine and the Lincoln area and on the west side of the Parker incense cedar do not grow in these areas. Mountain-Grizzly Mountain ridge. Whitethorn ceanothus is Associated sites.-The site Douglas Fir-Mixed Pine-Sedge an important component in areas of this site that are at the Forest, is on south-facing slopes and in areas that are northern end of Copco Road. At elevations of more than warmer and receive a smaller amount of precipitation. The 5,600 feet on Chase Mountain, this site supports a plant site Mixed Conifer-Chinkapin-Sedge Forest is in the eastern community adapted to drier conditions. part of the survey area, south and east of Aspen Lake. The Associated sites. The site Douglas Fir-Mixed Pine-Sedge site Wet Loamy Terrace is in areas near Aspen Lake where Forest is in areas that are warmer and receive a smaller the water table is higher. The site Ponderosa Pine-Fescue is amount of precipitation. The site Mixed Conifer- in areas that are warmer and drier, such as areas at low Bitterbrush-Sedge Forest is in the eastern part of the survey elevations in basins or bordering meadows. The site Wet area, south and east of Aspen Lake. The site Mixed Fir-Yew Meadow is in basins and near drainageways. The site Forest is north of Little Chinkapin Mountain. The site Wet Loamy Juniper Scabland, 20- to 30-inch precipitation zone, Meadow is in basins and near drainageways. The site is in areas where soil depth is limited. Loamy Juniper Scabland, 20- to 30-inch precipitation zone, Management and response to disturbance. -The more is in areas where soil depth is limited. palatable forage plants include western fescue, mountain Management and response to disturbance.-The more brome, Orcutt brome, tall trisetum, Ross sedge, Pacific palatable forage plants include western fescue, mountain serviceberry, willow, and antelope bitterbrush. The brome, Orcutt brome, tall trisetum, Ross sedge, willow, and understory includes many aggressive species that increase Pacific serviceberry. The understory includes many in abundance where selective logging allows additional light aggressive species that increase in abundance where to penetrate the canopy. In the more heavily logged areas, selective logging allows additional light to penetrate the including those that have been clearcut or burned, brush canopy. In the more heavily logged areas, including those fields can develop and greenleaf manzanita or snowbrush, that have been clearcut or burned, brush fields can develop or both, can invade. Also, the abundance of native shrubs, and snowbrush or greenleaf manzanita, or both, can such as antelope bitterbrush, tall Oregongrape, common invade. Also, the abundance of native shrubs, such as tall snowberry, squawcarpet, and sierra chinkapin, increases Oregongrape, willow, Pacific serviceberry, common considerably. Logging or burning creates open areas that snowberry, squawcarpet, and sierra chinkapin, support a greater abundance of shrubs, ponderosa pine, considerably increases. Logging or burning creates open incense cedar, sedge, mountain brome, Orcutt brome, and areas that support a greater abundance of shrubs, brackenfern and a few forbs. ponderosa pine, incense cedar, sedge, mountain brome, Orcutt brome, and brackenfern and a few forbs. Mixed Conifer-Chinkapin-Sedge Forest. The potential plant community on this site is dominated by Mixed Fir-Dogwood Forest. The potential plant Oregongrape, American twinflower, common snowberry, community on this site is dominated by white fir and and numerous light-sensitive species, such as deerfoot Douglas fir. Other conifers, which occur in small amounts, vanillaleaf and other forbs, thrive under the shade and thus include incense cedar, sugar pine, and an occasional increase in abundance. Later, as the stand matures or after Pacific yew. Common hardwoods in the overstory include selective logging, the understory composition can shift to a Pacific madrone, California black oak, golden chinkapin, new balance that favors the more light tolerant species, and an occasional bigleaf maple. The midstory is dominated depending on the amount of light penetrating the canopy. by Pacific dogwood. Understory shrubs include cascade Oregongrape, Pacific serviceberry, California hazel, Mixed Fir-Mixed Pine Forest. The potential plant creambush oceanspray, common snowberry, and wild rose. community on this site is dominated by Douglas fir, but Creeping vines, which are common, include yerba buena, sugar pine and white fir also are common in the overstory. American twinflower, Whipplevine, and hairy honeysuckle. Other coniferous trees include incense cedar and ponderosa Grasses, which are sparse, include western fescue, pine. Hardwood trees, including California black oak and crinkleawn fescue, mountain brome, Alaska oniongrass, Pacific madrone, are in the overstory. Pacific dogwood and and tall trisetum. Forbs, which are abundant, include golden chinkapin are common in the midstory. Understory deerfoot vanillaleaf, western white anemone, pathfinder, shrubs include deerbrush, Pacific serviceberry, California western swordfern, insideout flower, Pacific peavine, spring hazel, and common snowberry. Tall Oregongrape is the queen, and Pacific trillium. most abundant evergreen shrub, but smaller amounts of Site variation.-Some areas of this site that are at cascade Oregongrape, western princes pine, and American elevations of more than 4,000 feet or that are cold because twinflower also are evident. Grasses include western fescue, of restricted air drainage do not support Pacific madrone mountain brome, tall trisetum, blue wildrye, California and California black oak. The north-facing slopes between fescue, and Alaska oniongrass. Forbs include starflower, Little Chinkapin Mountain and the northeastern side of Soda spring queen, pathfinder, iris, and strawberry. Mountain support a plant community that is adapted to drier Associated sites.-The site Wet Meadow is in basins and conditions. Such species as Pacific madrone, deerfoot near drainageways. The sites Mixed Fir-Dogwood Forest vanillaleaf, and Whipplevine do not grow in these areas. and Mixed Fir-Western Hemlock Forest are on north-facing Associated sites. -The site Mixed Fir-Mixed Pine slopes. The site Mixed Fir-Serviceberry Forest is in areas Forest is on south-facing slopes. The sites Semi-Wet that are colder and are at the higher elevations. The site Meadow and Wet Meadow are in basins and near Pine-Douglas Fir-Fescue is in some areas. drainageways. Management and response to disturbance.-The more Management and response to disturbance.-The more palatable forage plants include western fescue, mountain palatable forage plants include western fescue, mountain brome, Alaska oniongrass, tall trisetum, and deerbrush. brome, crinkleawn fescue, Alaska oniongrass, tall trisetum, Because major disturbances in some areas result in the deerbrush, and creambush oceanspray. development of dense stands of brush, forage production Clearcutting or burning results in the development of is low and access by livestock is limited. dense stands of brush dominated by deerbrush, redstem Burning or clearcutting initiates sprouting of Pacific ceanothus, California hazel, creambush oceanspray, Pacific madrone and California black oak, which rapidly return to madrone, and California black oak. Other low shrubs the canopy. Brush fields readily form from a mixture of include common snowberry, American twinflower, shrubs, such as Pacific serviceberry, California hazel, Whipplevine, baldhip rose, and trailing blackberry. Where deerbrush, common snowberry, and tall Oregongrape. there is no Douglas fir or White fir overstory, most of the Pacific madrone and California black oak gradually become native grasses and forbs that require much light increase dominant on the site as they successfully compete with the considerably in abundance and ponderosa pine is likely to shrubs. regenerate. Ponderosa pine becomes prominent in the early stages Hardwoods eventually form a canopy that dominates of succession, but it thins out as competition for light begins the brush fields. As the new stand develops, however, the to limit reproduction. Douglas fir and white fir increase in hardwoods and brush fields are suppressed and then are abundance during the later stages of succession, as the overtopped by conifers. A dense overstory of Douglas fir density of the overstory increases. and white fir normally develops. The dense overstory Logging systems other than clearcutting have varied reduces the abundance of Pacific madrone and oak and the abundance of many understory species. Under these conditions, however, cascade effects on regeneration, depending upon the species incense cedar and scattered sugar pine, ponderosa pine, harvested, the amount of timber cut, and the extent of California black oak, and bigleaf maple. The midstory is surface disturbance. When the stand is opened up, the dominated by regenerated trees and tall shrubs, such as dominant species that regenerates is ponderosa pine. creambush oceanspray, Pacific serviceberry, and Also, the growth rate and degree of crown cover of any California hazel. Understory shrubs include cascade suppressed white fir in the stand increase. Oregongrape, common snowberry, baldhip rose, trailing blackberry, thimbleberry, and American twinflower. The Mixed Fir-Mixed Pine Forest, Wet. The potential plant grass cover, which is sparse, includes western fescue, community on this site is dominated by Douglas fir and mountain brome, crinkleawn fescue, and Alaska white fir. Other coniferous plants, which occur in smaller oniongrass. Forbs include starflower, western swordfern, amounts, include ponderosa pine, sugar pine, and incense pathfinder, Pacific peavine, western white anemone, cedar. Minor amounts of Pacific dogwood and western whitevein shinleaf, and scouler harebell. hemlock are in the midstory or understory. Understory Site variation. -Areas of this site at elevations of less than shrubs include common snowberry, Pacific serviceberry, 4,000 feet support Pacific madrone, California black oak, willow, Douglas spirea, American twinflower, cascade and scattered poison oak. Areas near King Mountain and Oregongrape, tall Oregongrape, and California hazel. Skeleton Mountain in the northwestern part of the survey Grasses and grasslike plants include sedge, mannagrass, area support many plants that are the same as those on the tall trisetum, mountain brome, western fescue, and blue Mixed Fir-Salal (rhododendron) Forest site, particularly wildrye. Forbs, which are abundant, include brackenfern, those that require a greater amount of precipitation. spring queen, strawberry, deerfoot vanillaleaf, fragrant Associated sites. The site Mixed Fir-Serviceberry Forest bedstraw, and insideout flower. In the wettest areas, they is on south-facing slopes. The sites Wet Meadow and also include horsetail. Semi-Wet Meadow are in basins and near drainageways. Site variation.-Areas where the water table is nearest Management and response to disturbance.-The more the surface or is high for extended periods support a palatable forage plants include mountain brome, western greater abundance of water-tolerant species, such as fescue, Alaska oniongrass, crinkleawn fescue, creambush mannagrass, horsetail, willow, Douglas spirea, and oceanspray, and Pacific serviceberry. Because of the ponderosa pine. hazard of erosion on the soils that formed in material Associated sites. -The site Mixed Fir-Mixed Pine derived from granitic rock, the more sloping areas should Forest is in areas where the soils do not have a water not be grazed. table. The site Wet Meadow is in basins and near Clearcutting or burning of the overstory results in the drainageways. development of dense stands of brush that include Management and response to disturbance.-The creambush oceanspray, Pacific serviceberry, California more palatable forage plants include sedge, mannagrass, hazel, common snowberry, baldhip rose, currant, tall trisetum, mountain brome, western fescue, willow, and thimbleberry, and gooseberry. In addition to shrubs, Pacific serviceberry. Clearcutting or burning of the overstory ponderosa pine and Douglas fir regenerate mainly during results in an increase in the abundance of herbaceous this stage of succession. Grasses and some forbs also species and the development of stands of brush that include become abundant in open areas created by logging or the willow, Douglas spirea, Pacific serviceberry, wild rose, less severe burns or as a result of the damage caused by California hazel, common snowberry, and tall Oregongrape. insects or disease. Selective logging of Douglas fir allows for Natural regeneration of ponderosa pine, incense cedar, and the growth of suppressed white fir, which rapidly closes the Douglas fir occurs after a disturbance. The amount of shade canopy. provided by the developing canopy and the tolerance of the plants to wetness influence plant succession. Mixed Fir-Salal (rhododendron) Forest. The potential plant community on this site is dominated by Douglas fir. Mixed Fir-Oceanspray Forest. The potential plant Other coniferous trees, which occur in small amounts, community on this site is dominated by white fir. Douglas fir include white fir, western hemlock, incense cedar, and sugar is a codominant species. Many stands are dominated by pine. Hardwoods in the overstory, which are of minor extent, Douglas fir and are characterized by much regenerated include golden chinkapin, Pacific madrone, and an white fir. As these stands mature, the white fir eventually occasional bigleaf maple. The midstory includes dominates the overstory. Other coniferous trees, which regenerated conifers, Pacific dogwood, and an occasional occur in small amounts, include Pacific yew. Understory shrubs include salal, Pacific rhododendron, cascade such as vanillaleaf, Pacific trillium, wild ginger, and Oregongrape, American twinflower, western princes pine, Pacific yew, decrease in abundance. creambush oceanspray, California hazel, Whipplevine, common snowberry, and red huckleberry. The grass Mixed Fir-Serviceberry Forest. The potential plant cover, which is sparse, includes western fescue, mountain community on this site is dominated by Douglas fir and brome, Alaska oniongrass, and crinkleawn fescue. Small white fir. Other coniferous trees, which occur in small amounts of sedge and common beargrass also are amounts, include ponderosa pine, incense cedar, and an evident. Forbs include deerfoot vanillaleaf, western occasional sugar pine. Hardwoods in the overstory, such as swordfern, starflower, insideout flower, small false Pacific madrone and California black oak, grow sporadically Solomons seal, trillium, calypso, and wild ginger. in the Siskiyou Mountains and on the western flank of the Site variation.-Some areas of this site, mainly those on Cascade Mountains. The midstory is dominated by the southern edge of the site's range and where elevation is regenerated conifers, Pacific serviceberry, and an less than 3,000 feet, do not support rhododendron. Areas at occasional creambush oceanspray, California hazel, willow, elevations of more than about 4,000 feet support or sierra chinkapin. Understory shrubs include common cold-tolerant plants, such as snow bramble, onesided snowberry, baldhip rose, gooseberry, currant, tall wintergreen, and big huckleberry. Because of a greater Oregongrape, cascade Oregongrape, western princes pine, amount of precipitation, these areas support a greater and pachystima. The grass cover, which is sparse, includes abundance of western hemlock. western fescue, mountain brome, tall trisetum, Alaska Associated sites.-The site Douglas Fir-Madrone- oniongrass, sedge, and blue wildrye. The prominent forbs Chinkapin Forest is on south-facing slopes. The sites include strawberry, spring queen, starflower, California Douglas Fir-Beargrass Forest, Serpentine, and Douglas vetch, mountain sweetroot, western white anemone, small Fir-Pine Forest, Serpentine, are in areas that are influenced false Solomons seal, and scouler harebell. by serpentine. Site variation.-Some areas where air drainage is Management and response to disturbance.-The more restricted support cold-tolerant species, such as Shasta fir, palatable forage plants include western fescue, mountain Pacific yew, and lodgepole pine. These areas are mainly on brome, Alaska oniongrass, and creambush oceanspray. the Dead Indian Plateau. Some areas at the lower The amount of forage is greater in areas that have been elevations on the western flank of the Cascade Mountains recently opened by disturbances, such as logging and fire, support California fescue and an abundance of California and as a result of the damage caused by disease or insects; black oak. In slump areas and in areas where the soils are however, these openings may eventually become clayey, ponderosa pine is more common and there are dominated by unpalatable evergreen species, such as salal, fewer species. The species in these areas include cascade Pacific rhododendron, manzanita, and golden chinkapin. As Oregongrape, western princes pine, and pachystima. a result, brush fields that may be dense enough to restrict Associated sites.-The site Mixed Fir-Oceanspray Forest access by livestock develop. The normal grazing periods for is on north-facing slopes in the Siskiyou Mountains and on livestock grazing are in summer or fall. Because of the west-facing slopes in the Cascade Mountains. The site hazard of erosion on the soils in areas of this site, which Mixed Fir-Yew Forest is on north-facing slopes on the Dead formed in material derived from granitic rock or schist, the Indian Plateau. The site Wet Meadow is in basins and near more sloping areas should not be grazed. drainageways. Clearcutting or burning of the overstory results in the Management and response to disturbance. -The more development of dense stands of brush that include shrubs, palatable forage plants include western fescue, mountain such as salal, Pacific rhododendron, creambush brome, tall trisetum, and Pacific serviceberry. oceanspray, American twinflower, Whipplevine, common Clearcutting or burning results in stands of brush that snowberry, rose, and trailing blackberry. Other shrubs, such include Pacific serviceberry, creambush oceanspray, willow, as snowbrush, hoary manzanita, and greenleaf manzanita, common snowberry, baldhip rose, sierra chinkapin, and invade some areas. Pacific madrone and golden chinkapin currant. These stands also include snowbrush and sprout rapidly. These species compete well and overtop the greenleaf manzanita, which invade the site. Where Pacific shrubs. In small openings created by selective logging or madrone and California black oak are included, sprouting is other disturbances in normal stands, the abundance of extensive in the stands of brush. aggressive shrubs and herbaceous species increases and Ponderosa pine regenerates most commonly in openings natural regeneration occurs. In the larger open areas, and during stages of succession when there is however, shade-tolerant plants that are sensitive, full exposure to light. Douglas fir and white fir regenerate depending on the species involved, the degree of cutting later in the succession under partial shade provided by or burning, and the extent of surface disturbance. brush and regenerated pine. Mountain brome, brackenfern, trailing blackberry, and strawberry become more abundant in open areas, where Mixed Fir-Western Hemlock Forest. The potential plant there is less competition for light and moisture. community on this site is dominated by white fir and Douglas fir. Other coniferous trees include western Mixed Fir-Yew Forest. The potential plant community on hemlock, sugar pine, incense cedar, and Pacific yew. this site is dominated by white fir. Douglas fir is a Hardwood trees are limited to golden chinkapin, Pacific codominant species. Minor amounts of western white pine dogwood, and Pacific madrone. The prominent tall shrubs and Shasta red fir are included in some stands. The are vine maple, California hazel, creambush oceanspray, midstory is dominated by an abundance of regenerated and Pacific serviceberry. The prominent low deciduous Pacific yew, sierra chinkapin, and conifers. Understory shrubs include thimbleberry, baldhip rose, common shrubs include cascade Oregongrape, common snowberry, snowberry, Whipplevine, and trailing blackberry. Cascade western princes pine, big huckleberry, pachystima, Oregongrape, American twinflower, and western princes gooseberry, American twinflower, and baldhip rose. pine are the most common evergreen shrubs, but smaller Grasses, which are of minor extent, include western fescue, amounts of tall Oregongrape also are evident. The grass mountain brome, Alaska oniongrass, and tall trisetum. cover, which is sparse because of the shade provided by Forbs, which are abundant, include insideout flower, the canopy, commonly includes western fescue, mountain starflower, western white anemone, wild ginger, onesided brome, Alaska oniongrass, and crinkleawn fescue. The site wintergreen, beadlily, and pathfinder. supports many forbs, such as deerfoot vanillaleaf, Site variation.-Areas of this site south of Oregon State starflower, insideout flower, western swordfern, and Highway 66 and on Grizzly Mountain, along the pathfinder. Jackson-Klamath County line, show the effects of less Site variation.-Nearly level areas that are not subject to precipitation and warmer temperatures. These areas pooling of cold air support less western hemlock, vine support hardwoods, such as California black oak and maple, and deerfoot vanillaleaf and more sugar pine, Pacific Pacific dogwood, and have a smaller amount of Pacific madrone, and ponderosa pine. In some areas vine maple yew. Some low areas on the Dead Indian Plateau where dominates the understory. Western hemlock dominates the air drainage is restricted support stands of lodgepole pine. overstory in some areas that are especially moist. Associated sites.-The site Wet Meadow is in basins and Associated sites.-The site Mixed Fir-Mixed Pine near drainageways. The site Mixed Fir-Serviceberry Forest Forest is on south-facing slopes and in areas that is on south-facing slopes. The site Mixed Fir-Oceanspray is receive a smaller amount of precipitation. on the western slopes of the Cascade Mountains. The site Management and response to disturbance.-The more Mixed Conifer-Chinkapin-Sedge Forest is in the upper part palatable forage plants include western fescue, mountain of the basin of Jenny Creek. brome, Alaska oniongrass, several forbs, and shrubs, such Management and response to disturbance.-The more as Pacific serviceberry and creambush oceanspray. palatable forage plants include mountain brome, western Clearcutting or burning generally results in the fescue, Alaska oniongrass, tall trisetum, and shrubs, such development of dense brush fields that include vine as Pacific serviceberry. maple, dewberry, chinkapin, California hazel, common Regenerating clearcut or burned areas that are not snowberry, and creambush oceanspray. Redstem replanted is difficult. Pacific yew slowly dies out when most ceanothus, deerbrush, snowbrush, and greenleaf of the protective conifer overstory is removed. Removal of manzanita invade the site. Because of cold temperatures the overstory or burning, or both, commonly is followed in some areas, conifers may be slow to regain dominance either by the growth of a cover of grasses and sedge or by of the site. Coniferous trees that emerge through the the development of brush fields. The stands of brush brush commonly have a better growth form and a better include gooseberry, blue elderberry, Pacific serviceberry, survival rate than those that are more exposed to the mountain ash, and common snowberry and invaders, such cold. In the absence of a brush cover, some grasses and as snowbrush and greenleaf manzanita. Stands of grasses sedge become very competitive and thus threaten the and sedge commonly provide habitat for large populations survival of tree seedlings. of rodents, especially gophers, which damage a large The response of plants to logging or burning varies, number of seedlings. Selective logging and thinning result in the rapid growth of suppressed white fir, Douglas Associated sites. -The site Douglas Fir-Beargrass fir, and incense cedar. These practices allow natural Forest, Serpentine, is in areas that are influenced by regeneration. Also, underplanting is somewhat successful serpentinite. The site Mixed Fir-Oceanspray Forest is on where these practices have been applied. north-facing slopes at the lower elevations. The site Mixed Fir-Serviceberry Forest is on south-facing slopes at the Mixed Pine -Douglas Fir-Fescue Forest, Granitic. lower elevations. The potential plant community on this site is dominated by Management and response to disturbance.-The more ponderosa pine and Douglas fir. Sugar pine, although palatable forage plants include sedge, mountain brome, important, is less common on the site, and incense cedar and western fescue. Disturbances, such as clearcutting grows only sporadically. Common hardwood trees in the and burning of the overstory, result in the development of overstory include Pacific madrone and California black oak. dense stands of brush that include invaders, such as Understory shrubs include deerbrush, Brewers lupine, greenleaf manzanita and snowbrush, and native shrubs, poison oak, common snowberry, tall Oregongrape, whiteleaf such as pinemat manzanita and sierra chinkapin. manzanita, and hairy honeysuckle. Grasses include Idaho Herbaceous species, such as sedge, white hawkweed, and fescue, western fescue, blue wildrye, mountain brome, common beargrass, increase in abundance in the prairie junegrass, tall trisetum, and California fescue. Forbs, disturbed areas. which are of minor extent, include white hawkweed, lupine, tarweed, iris, brackenfern, mountain sweetroot, and Pine -Douglas Fir-Fescue. The potential plant California bellflower. community on this site is dominated by ponderosa pine and Associated sites.-The site Douglas Fir-Mixed Pine- Douglas fir. Hardwood trees include California black oak Fescue Forest is in areas of deep soils that formed in and Pacific madrone. Other trees, which occur in minor material derived from granitic rock and have slopes of less amounts, include incense cedar, Oregon white oak, and than about 20 percent. The site Douglas Fir Forest is on canyon live oak. Understory shrubs include Pacific north-facing slopes. The site Pine-Douglas Fir-Fescue is on serviceberry, tall Oregongrape, common snowberry, the less sloping soils that are on south-facing slopes and deerbrush, birchleaf mountainmahogany, and poison oak. are not influenced by granitic rock. Grasses are abundant, particularly in areas where the Management and response to disturbance.-The more canopy is open. California fescue and Idaho fescue are the palatable forage plants include Idaho fescue, western dominant grasses. Other grasses include California brome, fescue, tall trisetum, prairie junegrass, and deerbrush. mountain brome, tall trisetum, prairie junegrass, and Because major disturbances result in the development of western fescue. Forbs include wooly eriophyllum, iris, dense stands of brush, forage production is low in some strawberry, hawkweed, and mountain sweetroot. areas and access by livestock is limited. Logging or burning Site variation.-In the older stands on this site, Douglas fir results in the development of dense stands of brush commonly is more abundant than ponderosa pine. Canyon dominated by whiteleaf manzanita and deerbrush. Poison live oak generally does not grow in the areas of this site in oak and sprouted Pacific madrone and California black oak the Cascade Mountains. Areas at elevations of more than also are abundant. Clearcutting or heavy partial cutting that 4,000 feet generally support small amounts of white fir, more removes many of the overstory plants can result in slow Douglas fir, and less Pacific madrone and poison oak. In regeneration of timber species. Very light partial cutting is some areas Oregon white oak and California black oak are less detrimental to the site and should promote the dominant. In the Siskiyou Mountains, onsite investigation regeneration of conifers. may be needed to distinguish areas of this site from areas of the sites Loamy Hills, 20- to 35-inch precipitation zone, and Noble Fir-Bush Chinkapin Forest. The potential plant Droughty North, 18- to 35-inch precipitation zone. community on this site is dominated by noble fir and white Associated sites.-The site Douglas Fir Forest is on fir. Other coniferous trees, which occur in small amounts, north-facing slopes. The site Douglas Fir-Mixed Pine- include Douglas fir and incense cedar. Understory shrubs Fescue Forest is in some areas. include sierra chinkapin, pinemat manzanita, currant, Management and response to disturbance.-The western princes pine, dwarf bramble, and big huckleberry. more palatable forage plants include Idaho fescue, Harford's Grasses and grasslike plants include sedge, mountain melica, tall trisetum, western fescue, and deerbrush. brome, and western fescue. Forbs include onesided Because major disturbances can result in the development wintergreen, small false Solomons seal, beadlily, whitevein of dense stands of brush, forage production is low in some shinleaf, western white anemone, and common beargrass. areas and access by livestock is limited. Figure 15.-The vegetative site Ponderosa Pine -Fescue in an area of Bly-Royst complex, 12 to 35 percent slopes. The shrubs In the understory are antelope bitterbrush.

Severe burning or clearcutting of the overstory can result commonly results in an increase in the abundance of the in the development of dense stands of deerbrush, poison hardwood overstory and shrubs, particularly in areas oak, whiteleaf manzanita, and hardwoods. Pacific madrone, where the surface has been disturbed. California black oak, and small amounts of Oregon white oak gradually become dominant on the site as they outgrow Ponderosa Pine -Fescue. The potential plant community the shrubs. Regeneration of ponderosa pine is evident in on this site is dominated by ponderosa pine (fig. 15). The the openings; however, Douglas fir is slow to return and site has no other trees, except for very small amounts of commonly grows only in the protective shade of the white fir, incense cedar, Douglas fir, and western juniper. hardwood canopy. Selective logging of conifers The midstory includes regenerated curlleaf or birchleaf mountainmahogany and ponderosa pine. Understory shrubs include antelope bitterbrush, zone, is in areas of patterned ground where the soils are common snowberry, squawcarpet, Pacific serviceberry, well drained. greenleaf manzanita, and Klamath plum. Grasses and Management and response to disturbance. -The grasslike plants include sedge, Idaho fescue, western more palatable forage plants include sedges and grasses, fescue, mountain brome, western needlegrass, and such as timothy and mannagrass. In many areas this site is wheeler bluegrass. Forbs include wooly wyethia, white too wet to be used for livestock grazing. Overgrazing results hawkweed, groundsel, American vetch, and strawberry. in a decrease in the abundance of the more palatable plants Associated sites. -The sites Douglas Fir-Mixed Pine- and an increase in the abundance of the less palatable Sedge Forest and Mixed Conifer-Bitterbrush-Sedge Forest herbaceous species. In a few areas, it also, results in an are in some areas. The site Deep Loamy, 16- to 20-inch increase in the abundance of blackberry. precipitation zone, is in areas that receive a smaller amount of precipitation. The sites Loamy Juniper Scabland, 20- to Semi-Wet Meadow.-The potential native plant 30-inch precipitation zone, and Droughty Slopes, 20- to community on this site is dominated by California 30-inch precipitation zone, are in areas where soil depth is oatgrass. The site supports sedge and minor amounts of limited. The site Wet Meadow is in basins and near Canada bluegrass, Kentucky bluegrass, timothy, slender drainageways. wheatgrass, and other grasses. Forbs, which are Management and response to disturbance. The abundant, include swamp buttercup, clover, cinquefoil, more palatable forage plants include Idaho fescue, sedge, Douglas aster, and brodiaea. Trees and shrubs are not Wheeler bluegrass, mountain brome, and western fescue. If common on this site; however, willow, birch, and spirea the site is grazed in the fall, they also include antelope grow in some areas. bitterbrush. Overgrazing for prolonged periods results in a Site variation.-Numerous areas of this site support an decrease in the abundance of the preferred forage plants occasional ponderosa pine, and some support a full and possible damage to tree reproduction. It also can result overstory of ponderosa pine. in minor increases in the abundance of bottlebrush Associated sites.-The site Droughty Fan, 18- to 26inch squirreltail, needlegrass, and pine bluegrass, although precipitation zone, is in areas of the better drained soils. changes in plant composition are more significantly The site Poorly Drained Bottom is in areas of the more influenced by surface disturbance, canopy removal, and poorly drained soils. The sites Clayey Hills, 20- to 35-inch competition among species for moisture and light. precipitation zone, and Loamy Hills, 20- to 35inch Ground fires tend to increase the potential for perennial precipitation zone, are in some areas. bunchgrasses, temporarily reduce the abundance of Management and response to disturbance.-The more bitterbrush, and reduce the density of young ponderosa palatable forage plants include California oatgrass, timothy, pine. Logging and burning can result in increases in the slender wheatgrass, redtop, and Kentucky bluegrass. abundance of greenleaf manzanita and squawcarpet. Minor Overgrazing for prolonged periods results in a decrease in invasions or increases in the abundance of big sagebrush, the abundance of California oatgrass and an increase in the green rabbitbrush, western juniper, cheatgrass, and thistle abundance of bluegrass and sedge. If overgrazing also are likely. Dense stands of stagnated regenerated continues, most of the oatgrass is removed and the stand is ponderosa pine develop in some areas following dominated by bluegrass, sedge, annual grasses, and disturbances. In such stands the abundance of grasses and numerous forbs, such as plantain, owlclover, western antelope bitterbrush is reduced. yarrow, brodiaea, aster, and cinquefoil. Although renovating is difficult, the site can produce high forage yields if it is Poorly Drained Bottom. The potential plant seeded to suitable species. community on this site includes rushes, sedges, mannagrass, cattails, willows, and timothy. Scattered Shallow Mountain Slopes, 22- to 30-inch California white oak or Oregon ash and clumps of precipitation zone. The potential plant community on this willows make up the overstory in some areas. site is dominated by Idaho fescue. Pine bluegrass, prairie Associated sites. Areas where the soils are better junegrass, and bluebunch wheatgrass also are prominent. drained include the sites Droughty Fan, 18- to 26-inch Forbs include wooly eriophyllum, lomatium, agoseris, precipitation zone; Deep Loamy Terrace, 18- to 28-inch Brewer lupine, hawkweed, brown peony, and balsamroot. precipitation zone; Loamy Hills, 20- to 35-inch precipitation Shrubs, which are sparse, include northern buckwheat, zone; and Semi-Wet Meadow. The site Biscuit-Scabland Klamath plum, tall Oregongrape, bitter cherry, and birchleaf (mound), 18- to 26-inch precipitation mountainmahogany. The site supports minor amounts of western juniper, ponderosa Chinkapin Forest are adjacent to this site. They are less pine, and Oregon white oak. influenced by serpentinite. The sites Douglas Fir-Beargrass Site variation.-Western juniper grows in the areas of this Forest, Serpentine, and Douglas Fir-Pine Forest, site in the eastern part of the survey area. Oregon white Serpentine, are in areas of the deeper soils that formed in oak generally grows at the low or intermediate elevations. material derived from serpentine. Birchleaf mountain mahogany and bitter cherry commonly Management and response to disturbance.-The more grow on the margins of the site, mainly at the higher palatable forage plants include sheep fescue and pine elevations. bluegrass. California brome, bottlebrush squirreltail, and Associated sites.-The site Loamy Shrub Scabland, 18- Lemmon needlegrass are important forage plants in areas to 35-inch precipitation zone, is in areas where the soils are where the site is in poor condition. A decrease in the less sloping. The sites Pine-Douglas Fir-Fescue and abundance of sheep fescue permits an increase in the Douglas Fir Forest are in areas adjacent to forested sites. abundance of such species as bottlebrush squirreltail, The site Droughty North, 18- to 35-inch precipitation zone, Lemmon needlegrass, pine bluegrass, deathcamas, field is on north-facing slopes. The site Loamy Hills, 20- to buttercup, and hawkweed. Fire is followed by sporadic 35-inch precipitation zone, is in some areas. regeneration of Jeffrey pine, knobcone pine, and incense Management and response to disturbance.-The more cedar in some areas. Whiteleaf manzanita and wedgeleaf palatable forage plants include Idaho fescue, bluebunch ceanothus can become prominent after a fire. wheatgrass, and pine bluegrass. Overgrazing eventually reduces the abundance of Idaho fescue and bluebunch Shasta Fir-White Pine -Princes Pine Forest. The wheatgrass. Lemmon needlegrass, which replaces these potential plant community on this site is dominated by perennial grasses, effectively protects the soils but is less Shasta red fir and white fir. Western white pine also is palatable as forage. If overgrazing continues, the site is common. Douglas fir and ponderosa pine occur only in converted to gray rabbitbrush, annual grasses, and annual small amounts. The midstory includes mainly regenerated forbs, such as medusahead wildrye, cheatgrass, soft chess, conifers. Understory shrubs, which are abundant, include hedgehog dogtail, Klamath weed, knotweed, and filaree. western princes pine, sierra chinkapin, gooseberry, The effects of burning vary on this site. Wildfire may pachystima, big huckleberry, dwarf bramble, common temporarily injure fire-sensitive Idaho fescue while snowberry, and wild rose. Grasses and grasslike plants stimulating the growth of bluebunch wheatgrass and gray include sedge, mountain brome, Alaska oniongrass, tall rabbitbrush, depending on the nature of the fire. Burns that trisetum, and western fescue. Forbs include scouler are not too severe invigorate the cover of perennial harebell, western white anemone, onesided wintergreen, bunchgrasses. wild ginger, fragrant bedstraw, and whitevein shinleaf. Associated sites.-The sites White Fir-White Pine Shallow Serpentine, 30- to 40-inch precipitation zone. Forest and Wet Meadow are in basins and near The potential plant community on this site is dominated by drainageways. The site White Fir-Shasta Fir Forest is on an open stand of Jeffrey pine. Some Douglas fir, incense south-facing slopes. cedar, and Pacific madrone grow in places, especially in the Management and response to disturbance. -The more understory. Shrubs, which are of minor extent, include palatable forage plants include sedge, mountain brome, tall shrubby buckwheat, wedgeleaf ceanothus, and whiteleaf trisetum, Alaska oniongrass, and western fescue. Forage manzanita in some areas. The understory is dominated by production in typical middle-aged or old-growth stands is grasses and forbs. Sheep fescue is the main grass, but the low in all areas, except for well lighted openings. Access by site supports minor amounts of Lemmon needlegrass, livestock is limited in some areas where major disturbances California fescue, pine bluegrass, California brome, and result in the development of dense stands of brush. bottlebrush squirreltail. Forbs include wooly eriophyllum, Clearcutting or burning of the overstory results in the lomatium, field buttercup, Indian dream fern, deathcamas, development of dense stands of brush that include sierra and western yarrow. chinkapin and invading shrubs, such as greenleaf Site variation.-Areas where the soils are deeper or manzanita and snowbrush. Sedge and grasses significantly receive a greater amount of precipitation support more increase in abundance and then interfere with the Pacific madrone, Douglas fir, and California fescue. regeneration of trees. White fir and Shasta red fir may be Associated sites. -The sites Douglas Fir-Chinkapin slow to reoccupy the site after the overstory is removed. Forest, Douglas Fir-Black Oak Forest, Mixed Fir-Salal These species depend on the shade and (rhododendron) Forest, and Douglas Fir-Madrone- protection from frost that are provided by stands of brush hairgrass and an increase in the abundance of the less and the more aggressive lodgepole pine that invades some palatable species, such as sedge. If overgrazing continues, disturbed areas. Partial cutting and the less severe burns tufted hairgrass is removed from the stand, which then promote regeneration and the growth of new seedlings of becomes dominated by sedge, meadow barley, redtop, white fir, Shasta red fir, and possibly Douglas fir. and native forbs, such as swamp buttercup, clover, false hellebore, and cinquefoil. Invaders, such as Kentucky Wet Loamy Terrace. The potential plant community on bluegrass, redtop, rush, and velvetgrass, are in some this site is dominated by ponderosa pine. Small amounts of overgrazed areas. lodgepole pine, incense cedar, white fir, and Douglas fir are in some areas. Stands of shrubs are dominated by Douglas White Fir Forest.-The potential native plant community spirea, but they also include common snowberry, Pacific on this site is dominated by white fir and has only traces of serviceberry, willow, squawcarpet, tall Oregongrape, and other conifers, Douglas fir, and incense cedar. The midstory trailing blackberry. Grasses include Idaho fescue, western is limited to scattered white fir and minor amounts of Rocky fescue, prairie junegrass, and Orcutt brome. Forbs include Mountain maple, Pacific serviceberry, and gooseberry. The wooly eriophyllum, mountain sweetroot, western yarrow, understory, which is sparse, includes shrubs, such as sticky cinquefoil, and strawberry. common snowberry, western princes pine, little princes pine, Site variation.-The wetter areas of this site support a cascade Oregongrape, and baldhip rose. Grasses include greater abundance of lodgepole pine and water-tolerant Canada bluegrass, Alaska oniongrass, western fescue, and species. Areas of the better drained soils support more mountain brome. Sedge also grows on the site. Forbs Douglas fir, white fir, and incense cedar and less Douglas include mountain sweetroot, scouler harebell, western white spirea. anemone, western baneberry, sandwort, candyflower, Associated sites.-The site Wet Meadow is in basins and starflower, fragrant bedstraw, small false Solomons seal, near drainageways. The sites Ponderosa Pine-Fescue and insideout flower, and trillium. Mixed Conifer-Bitterbrush-Sedge Forest are in some areas. Site variation.-In the northern part of the survey area, Management and response to disturbance.-The more areas of this site where the amount of precipitation is palatable forage plants include Idaho fescue, western greater support more cascade Oregongrape or support fescue, and Orcutt brome. Removal of the overstory or such plants as thimbleberry, brackenfern, wild ginger, and burning is likely to initiate regeneration of ponderosa pine deerfoot vanillaleaf. At elevations of more than 5,600 feet and increase the abundance of such plants as tall on Chase Mountain, areas of this site support a plant Oregongrape, trailing blackberry, Pacific serviceberry, community that is adapted to drier conditions. Sierra willow, and common snowberry. chinkapin is the most prominent understory species in these areas. Wet Meadow. The potential plant community on this site Associated sites.-The site Mixed Fir-Serviceberry is dominated by tufted hairgrass. Sedge and meadow barley Forest is on south-facing slopes. are important secondary species. Small amounts of mat Management and response to disturbance.-The muhly also are on the site. The most common forb is swamp production of palatable forage on this site is low, even in buttercup. Other prominent forbs include cinquefoil, Douglas areas that have been opened. Livestock graze such aster, and bigleaf lupine. Trees and shrubs are not species as Canada bluegrass, Alaska oniongrass, characteristic on this site, but quaking aspen, birch, spirea, mountain broom, sedge, and blue elderberry. or willow grows in some areas. Regeneration is extremely difficult in areas that have been Site variation.-Some areas adjacent to forested sites clearcut or burned. These disturbed areas have remained support an overstory of ponderosa pine. The proportion of open for long periods, and there has been some increase tufted hairgrass and sedge varies, depending on the degree in the abundance of forbs and gooseberry. Blue of wetness on the site. Some very wet areas are dominated elderberry has invaded these areas. by sedge. Lodgepole pine grows in some cold areas in the Cascade Mountains. White Fir-Shasta Fir Forest. The potential plant Management and response to disturbance.-The more community on this site is dominated by white fir and Shasta palatable forage plants include tufted hairgrass and red fir. Other conifers, which occur in small amounts, meadow barley. Overgrazing for prolonged periods results include ponderosa pine, western white pine, and Douglas in a decrease in the abundance of tufted fir. Understory plants, which are sparse, include shrubs, such as gooseberry, sierra chinkapin, common snowberry, western princes pine, and pachystima. The main grasses and grasslike plants are sedge and mountain brome, but the site supports some brome, tall trisetum, and western fescue. In heavily logged Alaska oniongrass and western fescue. Forbs include areas that are burned, there is a significant increase in the onesided wintergreen, scouler harebell, whitevein shinleaf, abundance of sedge, some shrubs, and ~` lodgepole pine. In wild ginger, and small false Solomons seal. some areas lodgepole pine is codominant in the stand during Associated sites.-The site Shasta Fir-White Pine- periods when white fir is becoming reestablished. Ponderosa Princes Pine Forest is on north-facing slopes. The site pine is most likely to regenerate following partial cutting, White Fir-White Pine Forest is in cold-air drainage basins. when it is under a lodgepole pine canopy, or following the The site Wet Meadow is in basins and near less severe burns. Since ponderosa pine is more sensitive to drainageways. frost than lodgepole pine, it does not readily become Management and response to disturbance. -The more established in large clearings that are not protected from cold palatable forage plants include sedge, mountain brome, temperatures. Alaska oniongrass, and western fescue. Forage production in typical middle-aged or old-growth stands is low in all Woodland Management and Productivity areas, except for well lighted openings and recently logged areas. Gary Kuhn, forester, Soil Conservation Service, helped prepare Clearcutting or burning of the overstory results in the this section. development of dense stands of brush that include invading This surrey area is one of the most productive shrubs, such as greenleaf manzanita and snowbrush, and timber-growing regions of North America. Favorable native shrubs, such as sierra chinkapin, gooseberry, and climate, fertile soils, and well adapted timber species common snowberry. Sedge and grasses increase account for the high productivity. The most productive significantly in abundance and can interfere with the timber sites are those at intermediate elevations, and the regeneration of trees. White fir and Shasta red fir may be least productive ones are those at the higher elevations. slow to reoccupy the site after the overstory has been About 64 percent of the survey area is classified as removed. These species depend on the shade and frost commercial forest land. About 42 percent of this land is protection provided by stands of brush and the more privately owned, and the rest is publicly owned. Most of the aggressive conifers, such as ponderosa pine and Douglas publicly owned forest land is managed by the Federal fir. Government. The rest is managed by the state and the Partial cutting and the less severe burns promote counties. The Forest Service, the Oregon State Department regeneration and the growth of new seedlings of white fir of Forestry, and local fire districts provide fire protection. and Shasta red fir. In some areas heavy partial cutting Jackson County produces 8 percent of the lumber promotes regeneration of Douglas fir and ponderosa pine. produced annually in the western part of Oregon. In 1986, it produced a total of about 525 million board feet. Of this White Fir-White Pine Forest. The potential plant total, 39 percent was produced from pine, mainly ponderosa community on this site is dominated by white fir. Western pine and sugar pine; 33 percent from Douglas fir; 27 percent white pine and ponderosa pine commonly are included in from white fir; and 2 percent from incense cedar. Forest the overstory. Small amounts of Douglas fir also are industry land provided 46 percent of the harvest; national included. The midstory includes scattered white fir, western forests, 35 percent; land administered by the Bureau of white pine, and lodgepole pine. Understory shrubs include Land Management, 18 percent; nonindustrial private land, 1 gooseberry, western princes pine, squawcarpet, pachystima, percent; and state land, 0.2 percent (15). The lumber mills in and wild rose. Grasses and grasslike plants include an Jackson County have the daily capacity to produce 3.5 to abundance of sedge. They also include mountain brome, 4.0 million board feet of lumber and 5.5 to 6.0 million square western fescue, tall trisetum, and blue wildrye. Forbs include feet of plywood. scouler harebell, onesided wintergreen, whitevein shinleaf, A substantial amount of firewood for wood stoves is western white anemone, small false Solomons seal, and produced from slash, as a by-product of thinning, and from fragrant bedstraw. woodland dominated by hardwoods. All species are used Associated sites. -The site Wet Meadow is near for firewood. Pacific madrone and Douglas fir are the most drainageways. The site Shasta Fir-White Pine-Princes Pine valuable ones for this use. Forest is in nearly level areas and on north-facing slopes. Some small ponderosa pine logs are used for the The site White Fir-Shasta Fir Forest is on south-facing construction of log homes. Other products include slopes. laminated beams, particle board, hardwood plywood, Management and response to disturbance. -The more palatable forage plants include sedge, mountain and wood chips for export and for domestic use. Ratings of seedling mortality indicate the degree to Soils vary in their ability to produce trees. Their depth, which soil or topographic conditions affect the mortality of fertility, texture, and available water capacity influence tree tree seedlings. Plant competition is not considered in the growth. Elevation, aspect, the kinds of soil, and climate ratings. The ratings apply to healthy, dormant seedlings determine the kinds of trees that can be expected to grow from good stock that are properly planted during a period on any given site. Available water capacity and the when sufficient moisture is received. Slight indicates that no thickness of the root zone are of major importance. problem is expected under normal conditions; moderate Elevation and aspect, or the direction that a slope faces, are indicates that some problems of mortality can be expected of particular importance in mountainous areas. The forested and that extra precautions are advisable; and severe soils in the survey area range from shallow to very deep, indicates that mortality will be high and that extra from nongravelly to extremely gravelly, and from fine precautions are essential for successful reforestation. textured to coarse textured. Because of the differences Wetness, droughtiness, and topographic conditions among the soils, as well as differences in climate, account for seedling mortality problems. To offset these topography, and geology, the forests vary in composition concerns, larger than usual planting stock, special site and productivity. preparation, a surface drainage system, or reinforcement Soil surveys are important to woodland managers planting may be needed. seeking ways to increase the productivity of woodland. Ratings of windthrow hazard are based on soil Some soils respond better to applications of fertilizer than characteristics that affect the development of tree roots and others, some are more susceptible to landslides and the ability of the soil to hold trees firmly. A rating of slight erosion after roads are built and timber is harvested, and indicates that trees are not normally blown down during wet some require special harvesting and reforestation efforts. periods when winds are moderate or strong; moderate Table 7 summarizes the forestry information given in the indicates that an occasional tree may be blown down during detailed soil map unit descriptions and provides a means of these periods; and severe indicates that many trees may be quickly finding woodland interpretations. Map unit symbols blown down during these periods. are listed in the table, and the site index for each unit is A restricted rooting depth in a soil that has a high water given. The major management concerns also are given. table, bedrock, or an impervious layer and poor anchoring In table 7, the soils are rated for a number of factors to of roots in a loose soil are responsible for windthrow. be considered in woodland management. Slight, moderate, Moderate and severe ratings indicate the need for care in and severe indicate the degree of the major soil limitation. thinning forest stands, the periodic removal of windblown For each moderate or severe rating, a sentence in the trees, and an adequate road and trail system that allows for applicable detailed soil map unit addresses that rating. the removal of those trees. Ratings of equipment limitation reflect soil characteristics Ratings of plant competition refer to the likelihood of the that limit the use of equipment. A rating of slight indicates invasion of undesirable plants when openings are made in that equipment use is not normally ' restricted because of the tree canopy. A rating of slight indicates that unwanted soil factors; moderate indicates that there is a short plants are not likely to delay the development of natural or seasonal limitation because of soil wetness, a fluctuating planted seedlings; moderate indicates that competition will water table, or some other factor; and severe indicates that delay reforestation; and severe indicates that competition there is a seasonal limitation, a need for special equipment, can be expected to prevent reforestation. or a hazard affecting the use of equipment. Favorable climate and soil characteristics result in plant Slope, wetness, and the susceptibility of the soil to competition. Generally, the key to predicting plant compaction are the main factors that cause an equipment competition problems is the quantity of and proximity to limitation. As the gradient and length of slopes increase, seed sources of undesirable plants or the quantity of operating wheeled equipment becomes more difficult. On unwanted brush rootstock that will resprout after the steeper slopes, tracked equipment must be used. On the harvesting. Moderate and severe ratings indicate the need steepest slopes, cable yarding systems may be needed. for careful and thorough site preparation and the potential Wetness, especially in areas where the soil is fine textured, need for mechanical or chemical treatment to delay the can severely limit the use of equipment and make growth of competing vegetation. harvesting practical only during the dry period in summer. The potential productivity of common trees on a soil is Compaction is always a concern where silvicultural activities expressed as a site index and a productivity class. The site are performed. index is determined by measuring the height and age of selected trees in stands of a given species. The procedure for calculating the site index is described in that natural reforestation can take place. The methods that publications cited at the back of this survey for the following can be used to prepare a site include prescribed burning, species: Douglas fir (3, 7, 9); ponderosa pine and Jeffrey mulching, mechanical treatment, and chemical treatment. pine (11); Shasta red fir (19); and white fir (20). The site The actual methods used depend on such factors as the index applies to fully stocked, even-aged stands of trees slope, the kind of soil, and federal and state regulations. growing on a particular detailed soil map unit. The highest Prescribed burning reduces the quantity of logging timber yields can be expected on those map units that have debris, exposes mineral soil material suitable for natural the highest site indexes. Site index values can be converted seeding, and reduces the amount of competing vegetation. into estimated yields at various ages by carefully using the Severe burns, however, can reduce productivity by appropriate yield tables. destroying the duff layer, can reduce the amount of nitrogen The productivity class is based on a uniform system used in the soil, and can increase the hazard of erosion. The to indicate the potential productivity of an individual soil. The severity of prescribed burns should be kept low. Burning in productivity class is a number that denotes the potential winter and spring, when the moisture content of the fuel productivity in terms of cubic meters of wood per hectare usually is high, reduces the intensity of burns. per year for the indicator tree species (the species that is Mulch consisting of such material as paper and listed first in the detailed soil map units and in table 7 for a polyester fiber can be placed around the base of particular map unit). Potential productivity is based on the seedlings to control competition from other vegetation site index and the corresponding culmination of mean and minimize the loss of soil moisture through annual increment. For example, the number 1 indicates a transpiration and evaporation. potential production of 1 cubic meter of wood per hectare Mechanical treatment can consist of such practices as per year (14.3 cubic feet per acre per year) and 10 indicates the manual cutting of brush, the use of hand tools to scalp a potential production of 10 cubic meters of wood per the vegetation around seedlings, or land treatment involving hectare per year (143 cubic feet per acre per year). the use of heavy equipment. Manual cutting removes brush Trees to plant are those that are suited to the soils and sprouted hardwoods from the more sloping soils. Heavy and to commercial wood production. equipment commonly is used to distribute logging debris This survey area is characterized by a wide variety of and brush over areas of gently sloping soils. geologic, climatic, and topographic conditions and thus a Chemical treatment is effective in controlling the invasion variety of vegetative sites. The main kind of site is one on of brush and the sprouting of hardwoods, particularly in which Douglas fir is the primary tree species, but the sites in areas where the use of ground equipment is limited. the area range from those on which Oregon white oak is the Seedling mortality results from several site factors, sole tree species to mixed stands of Shasta fir, white fir, and including climate, aspect, topography, and kind of soil. western white pine. A more detailed description of Other factors to be considered are the damage caused by vegetative sites is given under the heading "Vegetative animals, the quality of the planting stock, and the species to Zones and Sites." Because of the variety of vegetative sites be planted. Seedling mortality generally is more severe on in the survey area, forest management is complex and sites that are hot and dry, particularly from late in spring includes many factors. through summer, and on sites that are cold. On hot, dry The major concern in managing the forested areas in the sites, seedling mortality commonly results from moisture survey area is reforestation, which is influenced by plant stress and from tissue damage near the soil-stem boundary. competition, site preparation, seedling mortality, erosion, In cold areas frost in summer kills exposed seedlings, and compaction. Plant competition depends on the nature particularly those of Douglas fir and true firs. Ponderosa of the native plants on a given site or on adjacent sites and pine is less susceptible to summer frost. If the seedlings are the ability of the plants to increase in abundance or to not killed, terminal bud damage results in poor growth form invade after a stand has been opened. These plants and may reduce productivity until the crown of the tree commonly are hardwood trees, shrubs, grasses, and forbs, reaches a height above the layer of cold air. depending on the characteristics of the soil and the nature Such timber management practices as clearcutting may of the geographic area. Invaders compete with the influence the seedling mortality rate in cold areas. desirable tree species primarily for moisture but also for Depending on the size of the clearcut area and its sunlight and nutrients. topographic position, an artificial pocket of cold air can be Site preparation involves reducing the amount of created. The cold air can increase the seedling logging debris and understory vegetation on the site so mortality rate. Management practices that leave a certain Erosion generally is not a problem in undisturbed areas. number of overstory trees on the site reduce the potential It is a hazard, however, in areas that have been logged, for seedling mortality because the trees tend to disrupt the burned, or otherwise disturbed. The severity of the hazard flow of the layer of cold air. depends on several factors, including the kind of soil, the Because seedlings receive more direct sunlight on slope, and the extent of surface disturbance. south-facing slopes, seedling mortality generally is more Access roads are the most important source of runoff severe on these slopes than on north-facing slopes. Various and stream sedimentation. Appropriate erosion-control devices that provide artificial shade, such as shade cards, practices and road maintenance procedures are needed to, wood shingles, styrofoam cups, and rocks and debris, are maintain the integrity of the roads and to prevent severe effective in reducing the seedling mortality rate in some erosion and the resulting sedimentation of streams. areas. The seedling survival rate generally is higher on north-facing slopes, which receive less direct sunlight and Recreation are cooler and more moist than south-facing slopes. Topography is important in determining the degree of Recreation is of major importance to the economy of the seedling mortality. In general, the seedling mortality rate is survey area. Outdoor activities, such as water sports, are higher on the steeper south-facing slopes than on other growing in popularity. The Rogue, Applegate, and Klamath slopes. It also commonly is higher in basins and nearly level Rivers provide opportunities for rafting or kayaking on white areas where cold air can pool than in areas where air water rapids. Fishing for salmon, steelhead, and trout is a drainage is good. major activity on the rivers and their tributaries. The The soil characteristics that influence seedling mortality mountain lakes and reservoirs in the area are popular sites include the content of rock fragments, depth, and texture. for boating, waterskiing, and swimming. The reservoirs and Coarse textured soils and soils that have a high content of other small water impoundments at the lower elevations rock fragments and a dark surface layer tend to reach support a warmwater sport fishery of bass and crappie. higher temperatures, which result in a higher potential for Winter sports have grown in popularity in recent years. seedling mortality. The characteristics that result in a higher Mt. Ashland, which is a popular area for downhill and available water capacity, such as a greater depth, a lower cross-country skiing, offers such facilities as lifts and a content of rock fragments, and medium texture, reduce the lodge. The Dead Indian Plateau is popular with seedling mortality rate. cross-country skiers and snowmobilers. The damage to seedlings caused by insects, deer, elk, Several areas that are noted for their scenic qualities and rodents can be significant in some areas. The quality attract many campers, hikers, and other nature enthusiasts. of the seedling stock and the experience of the planting Visitors also have access to Crater Lake National Park and crew also are important in determining the survival rate of to the Sky Lakes and Mountain Lakes Wilderness Areas. seedlings. The Pacific Crest Trail, a national scenic trail, traverses the Species vary in their susceptibility to the injury or death High Cascades and the Klamath Mountains in the Mt. caused environmental factors. Ponderosa pine seedlings Ashland area. The Table Rocks area also is popular with generally are more successful than Douglas fir seedlings hikers. The Bear Creek Greenway offers a greenbelt if they are planted in areas where the seedling mortality recreation site that is close to urban centers. Many public rate is high as a result of a high temperature in the and private campgrounds are beside the various mountain surface layer, moisture stress, or cold temperatures. lakes and streams in the survey area. Many wildlife species Compaction caused ground equipment used in in the area are available for observing, photographing, and harvesting and site preparation can reduce forest hunting. productivity and increase the hazards of erosion and The soils of the survey area are rated in table 8 sedimentation. Most soils are susceptible to compaction. according to limitations that affect their suitability for The degree of compaction depends on such soil recreation. The ratings are based on restrictive soil characteristics as the moisture content, the content of features, such as wetness, slope, and texture of the organic matter, the content of rock fragments, structure, surface layer. Susceptibility to flooding is considered. Not and texture. It also depends on the load applied to the considered in the ratings, but important in evaluating a site, soils. Because only a few trips over the same area can are the location and accessibility of the area, the size and cause significant compaction, machine traffic should be shape of the area and its scenic quality, vegetation, access restricted to designated skid trails. to water, potential water impoundment sites, and access to public sewer lines. The moderate slopes and few or no stones or boulders on the capacity of the soil to absorb septic tank effluent and the surface. ability of the soil to support vegetation are also important. Golf fairways are subject to heavy foot traffic and some Soils subject to flooding are limited for recreational uses by light vehicular traffic. Cutting or filling may be required. The the duration and intensity of flooding and the season when best soils for use as golf fairways are firm when wet, are not flooding occurs. In planning recreational facilities, onsite dusty when dry, and are not subject to prolonged flooding assessment of the height, duration, intensity, and frequency during the period of use. They have moderate slopes and no of flooding is essential. stones or boulders on the surface. The suitability of the soil In table 8, the degree of soil limitation is expressed as for tees or greens is not considered in rating the soils. slight, moderate, or severe. Slight means that soil properties generally are favorable and that limitations are Wildlife Habitat minor and easily overcome. Moderate means that limitations can be overcome or alleviated by planning, By Duane Setness, soil scientist, Soil Conservation Service. design, or special maintenance. Severe means that soil The kinds and numbers of wildlife species in the survey properties are unfavorable and that limitations can be offset area generally are related to the kinds of soil in the area. This only by costly soil reclamation, special design, intensive relationship is indirect and is influenced mainly by the kinds maintenance, or limited use, or by a combination of these of plant communities, climate, topography, and land use. measures. Natural plant communities consist of a variety of vegetation, The information in table 8 can be supplemented by other most of which is valuable to wildlife. Wildlife habitat can be information in this survey, for example, interpretations for created or improved by planting appropriate vegetation, by dwellings without basements and for local roads and maintaining the existing plant cover, or by promoting the streets in table 9 and interpretations for septic tank natural establishment of desirable plants. absorption fields in table 10. The survey area is characterized by diverse Camp areas require site preparation, such as shaping environmental conditions that provide many types of wildlife and leveling the tent and parking areas, stabilizing roads habitat and therefore an abundance of wildlife species. The and other intensively used areas, and installing sanitary conditions in the area range from those of the warm, facilities and utility lines. Camp areas are subject to heavy low-elevation flood plains and terraces in the central part of foot traffic and some vehicular traffic. The best soils are the area to those of the cold, high mountainous areas in the gently sloping and are not wet or subject to flooding during eastern part. the period of use. The surface has few, if any, stones or Water resources in the survey area include abundant boulders, absorbs rainfall readily but remains firm, and is not ponds, lakes, and rivers, which provide high-quality habitat dusty when dry. Strong slopes and stones or boulders can for many kinds of animals and fish. They also provide food greatly increase the cost of constructing campsites. and cover for many kinds of birds, including pheasant, Picnic areas are subject to heavy foot traffic. Most valley quail, and migratory ducks and geese. Such animals vehicular traffic is confined to access roads and parking as beaver and muskrat inhabit the streams and other water areas. The best soils for picnic areas are firm when wet, are areas. not dusty when dry, are not subject to flooding during the The Rogue River and its tributaries are used extensively period of use, and do not have slopes or stones or boulders by anadromous fish, such as coho salmon, chinook that increase the cost of shaping sites or of building access salmon, and steelhead trout. The number of anadromous roads and parking areas. fish in this river and its tributaries ranks second only to that Playgrounds require soils that can withstand intensive in the Columbia River. Other fish include rainbow trout, foot traffic. The best soils are almost level and are not wet or cutthroat trout, warmwater game, and nongame fish, such subject to flooding during the season of use. The surface is as crappie, bass, catfish, and carp. Some areas are free of stones and boulders, is firm after rains, and is not suitable for the construction of small fish ponds and other dusty when dry. If grading is needed, the depth of the soil water impoundments. over bedrock or a hardpan should be considered. Other wildlife that commonly inhabit this survey area Paths and trails for hiking and horseback riding include blacktail deer; mule deer, black bear, elk, bobcat, should require little or no cutting and filling. The best mountain lion, coyote, beaver, muskrat, mink, otter, soils are not wet, are firm after rains, are not dusty when weasel, skunk, raccoon, rabbit, rattlesnake, several kinds dry, and are not subject to flooding more than once a of squirrels, wood rats, mountain beaver, mice, moles, and year during the period of use. They have gophers. The survey area has many kinds of resident and migrant birds, including hawks, owls, quail, band-tailed pigeon, grouse, wild turkeys, ducks, shrink-swell potential, available water capacity, and geese, mourning dove, crows, jays, herons, bald eagle, other behavioral characteristics affecting engineering osprey, and many kinds of woodpeckers, flycatchers, and uses. songbirds. Several kinds of snakes, lizards, and This information can be used to evaluate the potential of salamanders also are common. areas for residential, commercial, industrial, and Much of the acreage in the survey area is used for recreational uses; make preliminary estimates of cultivated crops, hay and pasture, or livestock grazing. The construction conditions; evaluate alternative routes for crops and the vegetation along fences and irrigation ditches roads, streets, highways, pipelines, and underground provide some food and cover for wildlife. Urbanization, cables; evaluate alternative sites for sanitary landfills, industrial development, and intensive agriculture have septic tank absorption fields, and sewage lagoons; plan influenced wildlife populations in the central part of the detailed onsite investigations of soils and geology; locate survey area. potential sources of gravel, sand, earthfill, and topsoil; plan drainage systems, irrigation systems, ponds, terraces, and Engineering other structures for soil and water conservation; and predict performance of proposed small structures and pavements This section provides information for planning land uses by comparing the performance of existing similar structures related to urban development and to water management. on the same or similar soils. Soils are rated for various uses, and the most limiting The information in the tables, along with the soil maps, features are identified. The ratings are given in the following the soil descriptions, and other data provided in this tables: Building Site Development, Sanitary Facilities, survey, can be used to make additional interpretations. Construction Materials, and Water Management. The Some of the terms used in this soil survey have a ratings are based on observed performance of the soils and special meaning in soil science and are defined in the on the estimated data and test data in the "Soil Properties" "Glossary." section. Information in this section is intended for land use Building Site Development planning, for evaluating land use alternatives, and for Table 9 shows the degree and kind of soil limitations that planning site investigations prior to design and affect shallow excavations, dwellings with and without construction. The information, however, has limitations. basements, small commercial buildings, local roads and For example, estimates and other data generally apply streets, and lawns and landscaping. The limitations are only to that part of the soil within a depth of 5 or 6 feet. considered slight if soil properties and site features Because of the map scale, small areas of different soils generally are favorable for the indicated use and limitations may be included within the mapped areas of a specific are minor and easily overcome; moderate if soil properties soil. or site features are not favorable for the indicated use and The information is not site specific and does not special planning, design, or maintenance is needed to eliminate the need for onsite investigation of the soils or for overcome or minimize the limitations; and severe if soil testing and analysis by personnel experienced in the properties or site features are so unfavorable or so difficult design and construction of engineering works. to overcome that special design, significant increases in Government ordinances and regulations that restrict construction costs, and possibly increased maintenance are certain land uses or impose specific design criteria were not required. Special feasibility studies may be required where considered in preparing the information in this section. Local the soil limitations are severe. ordinances and regulations should be considered in Shallow excavations are trenches or holes dug to a planning, in site selection, and in design. maximum depth of 5 or 6 feet for basements, graves, utility Soil properties, site features, and observed performance lines, open ditches, and other purposes. The ratings are were considered in determining the ratings in this section. based on soil properties, site features, and observed During the fieldwork for this soil survey, determinations were performance of the soils. The ease of digging, filling, and made about grain-size distribution, liquid limit, plasticity compacting is affected by the depth to bedrock, a cemented index, soil reaction, depth to bedrock, hardness of bedrock pan, or a very firm dense layer; stone content; soil texture; within 5 or 6 feet of the surface, soil wetness, depth to a and slope. The time of the year that excavations can be seasonal high water table, slope, likelihood of flooding, made is affected by the depth to a seasonal high water natural soil structure aggregation, and soil density. Data table and the susceptibility of the soil to flooding: The were collected about kinds of clay minerals, mineralogy of resistance of the sand and silt fractions, and the kind of adsorbed cations. Estimates were made for erodibility, permeability, corrosivity, the excavation walls or banks to sloughing or caving is are so unfavorable or so difficult to overcome that affected by soil texture and depth to the water table. special design, significant increases in construction Dwellings and small commercial buildings are structures costs, and possibly increased maintenance are built on shallow foundations on undisturbed soil. The load required. limit is the same as that for single-family dwellings no higher Table 10 also shows the suitability of the soils for use than three stories. Ratings are made for small commercial as daily cover for landfills. A rating of good indicates that buildings without basements, for dwellings with basements, soil properties and site features are favorable for the use and for dwellings without basements. The ratings are based and good performance and low maintenance can be on soil properties, site features, and observed performance expected; fair indicates that soil properties and site of the soils. A high water table, flooding, shrink -swell features are moderately favorable for the use and one or potential, and organic layers can cause the movement of more soil properties or site features make the soil less footings. A high water table, depth to bedrock or to a desirable than the soils rated good; and poor indicates cemented pan, large stones, and flooding affect the ease of that one or more soil properties or site features are excavation and construction. Landscaping and grading that unfavorable for the use and overcoming the unfavorable require cuts and fills of more than 5 or 6 feet are not properties requires special design, extra maintenance, or considered. costly alteration. Local roads and streets have an all-weather surface and Septic tank absorption fields are areas in which effluent carry automobile and light truck traffic all year. They have a from a septic tank is distributed into the soil through subgrade of cut or fill soil material; a base of gravel, crushed subsurface tiles or perforated pipe. Only that part of the soil rock, or stabilized soil material; and a flexible or rigid between depths of 24 and 72 inches is evaluated. The surface. Cuts and fills generally are limited to less than 6 ratings are based on soil properties, site features, and feet. The ratings are based on soil properties, site features, observed performance of the soils. Permeability, a high and observed performance of the soils. Depth to bedrock or water table, depth to bedrock or to a cemented pan, and to a cemented pan, a high water table, flooding, large flooding affect absorption of the effluent. Large stones and stones, and slope affect the ease of excavating and grading. bedrock or a cemented pan interfere with installation. Soil strength (as inferred from the engineering classification Unsatisfactory performance of septic tank absorption of the soil), shrink -swell potential, frost action potential, and fields, including excessively slow absorption of effluent, depth to a high water table affect the traffic-supporting surfacing of effluent, and hillside seepage, can affect public capacity. health. Ground water can be polluted if highly permeable Lawns and landscaping require soils on which turf and sand and gravel or fractured bedrock is less than 4 feet ornamental trees and shrubs can be established and below the base of the absorption field, if slope is excessive, maintained. The ratings are based on soil properties, site or if the water table is near the surface. There must be features, and observed performance of the soils. Soil unsaturated soil material beneath the absorption field to reaction, a high water table, depth to bedrock or to a filter the effluent effectively. Many local ordinances require cemented pan, the available water capacity in the upper 40 that this material be of a certain thickness. inches, and the content of salts, sodium, and sulfidic Sewage lagoons are shallow ponds constructed to hold materials affect plant growth. Flooding, wetness, slope, sewage while aerobic bacteria decompose the solid and stoniness, arid the amount of sand, clay, or organic matter liquid wastes. Lagoons should have a nearly level floor in the surface layer affect trafficability after vegetation is surrounded by cut slopes or embankments of compacted established. soil. Lagoons generally are designed to hold the sewage within a depth of 2 to 5 feet. Nearly impervious soil material Sanitary Facilities for the lagoon floor and sides is required to minimize Table 10 shows the degree and the kind of soil seepage and contamination of ground water. limitations that affect septic tank absorption fields, sewage Table 10 gives ratings for the natural soil that makes up lagoons, and sanitary landfills. The limitations are the lagoon floor. The surface layer and, generally, 1 or 2 considered slight if soil properties and site features feet of soil material below the surface layer are excavated generally are favorable for the indicated use and limitations to provide material for the embankments. The ratings are are minor and easily overcome; moderate if soil properties based on soil properties, site features, and observed or site features are not favorable for the indicated use and performance of the soils. Considered in the ratings are special planning, design, or maintenance is needed to slope, permeability, a high water table, overcome or minimize the limitations; and severe if soil properties or site features depth to bedrock or to a cemented pan, flooding, large Material from the surface layer should be stockpiled for use stones, and content of organic matter. as the final cover. Excessive seepage resulting from rapid permeability in the soil or a water table that is high enough to raise the Construction Materials level of sewage in the lagoon causes a lagoon to function Table 11 gives information about the soils as a source unsatisfactorily. Pollution results if seepage is excessive or of roadfill, sand, gravel, and topsoil. The soils are rated if floodwater overtops the lagoon. A high content of organic good, fair, or poor as a source of roadfill and topsoil. They matter is detrimental to proper functioning of the lagoon are rated as a probable or improbable source of sand and because it inhibits aerobic activity. Slope, bedrock, and gravel. The ratings are based on soil properties and site cemented pans can cause construction problems, and features that affect the removal of the soil and its use as large stones can hinder compaction of the lagoon floor. construction material. Normal compaction, minor Sanitary landfills are areas where solid waste is processing, and other standard construction practices are disposed of by burying it in soil. There are two types of assumed. Each soil is evaluated to a depth of 5 or 6 feet. landfill-trench and area. In a trench landfill, the waste is Roadfill is soil material that is excavated in one place placed in a trench. It is spread, compacted, and covered and used in road embankments in another place. In this daily with a thin layer of soil excavated at the site. In an table, the soils are rated as a source of roadfill for low area landfill, the waste is placed in successive layers on embankments, generally less than 6 feet high and less the surface of the soil. The waste is spread, compacted, exacting in design than higher embankments. and covered daily with a thin layer of soil from a source The ratings are for the soil material below the surface away from the site. layer to a depth of 5 or 6 feet. It is assumed that soil layers Both types of landfill must be able to bear heavy will be mixed during excavating and spreading. Many soils vehicular traffic. Both types involve a risk of ground- have layers of contrasting suitability within their profile. The water pollution. Ease of excavation and revegetation table showing engineering index properties provides should be considered. detailed information about each soil layer. This information The ratings in table 10 are based on soil properties, site can help to determine the suitability of each layer for use as features, and observed performance of the soils. roadfill. The performance of soil after it is stabilized with lime Permeability, depth to bedrock or to a cemented pan, a high or cement is not considered in the ratings. water table, slope, and flooding affect both types of landfill. The ratings are based on soil properties, site features, Texture, stones and boulders, highly organic layers, soil and observed performance of the soils. The thickness of reaction, and content of salts and sodium affect trench type suitable material is a major consideration. The ease of landfills. Unless otherwise stated, the ratings apply only to excavation is affected by large stones, a high water table, that part of the soil within a depth of about 6 feet. For and slope. How well the soil performs in place after it has deeper trenches, a limitation rated slight or moderate may been compacted and drained is determined by its strength not be valid. Onsite investigation is needed. (as inferred from the engineering classification of the soil) Daily cover for landfill is the soil material that is used to and shrink -swell potential. cover compacted solid waste in an area sanitary landfill. Soils rated good contain significant amounts of sand or The soil material is obtained offsite, transported to the gravel, or both. They have at least 5 feet of suitable landfill, and spread over the waste. material, a low shrink -swell potential, few cobbles and Soil texture, wetness, coarse fragments, and slope affect stones, and slopes of 15 percent or less. Depth to the water the ease of removing and spreading the material during wet table is more than 3 feet. Soils rated fair are more than 35 and dry periods. Loamy or silty soils that are free of large percent silt- and clay -sized particles and have a plasticity stones or excess gravel are the best cover for a landfill. index of less than 10. They have a moderate shrink -swell Clayey soils are sticky or cloddy and are difficult to spread; potential, slopes of 15 to 25 percent, or many stones. Depth sandy soils are subject to soil blowing. to the water table is 1 to 3 feet. Soils rated poor have a After soil material has been removed, the soil material plasticity index of more than 10, a high shrink-swell remaining in the borrow area must be thick enough over potential; many stones, or slopes of more than 25 percent. bedrock, a cemented pan, or the water table to permit They are wet, and depth to the water table is less than 1 revegetation. The soil material used as final cover for a foot. These soils may have layers of suitable material, but landfill should be suitable for plants. The surface layer the material is less than 3 feet thick. generally has the best workability, more organic matter, Sand and gravel are natural aggregates suitable for and the best potential for plants. commercial use with a minimum of processing. They are Organic matter greatly increases the absorption and used in many kinds of construction. Specifications for retention of moisture and nutrients for plant growth. each use vary widely. In table 11, only the probability of finding material in suitable quantity is evaluated. The Water Management suitability of the material for specific purposes is not Table 12 gives information on the soil properties and site evaluated, nor are factors that affect excavation of the features that affect water management. The degree and material. kind of soil limitations are given for pond reservoir areas The properties used to evaluate the soil as a source of and for embankments, dikes, and levees. The limitations sand or gravel are gradation of grain sizes (as indicated by are considered slight if soil properties and site features the engineering classification of the soil), the thickness of generally are favorable for the indicated use and limitations suitable material, and the content of rock fragments. Kinds are minor and are easily overcome; moderate if soil of rock, acidity, and stratification are given in the taxonomic properties or site features are not favorable for the indicated unit descriptions. Gradation of grain sizes is given in the use and special planning, design, or maintenance is table on engineering index properties. needed to overcome or minimize the limitations; and severe A soil rated as a probable source has a layer of clean if soil properties or site features are so unfavorable or so sand or gravel or a layer of sand or gravel that is as much difficult to overcome that special design, significant increase as 12 percent silty fines. This material must be at least 3 in construction costs, and possibly increased maintenance feet thick and less than 50 percent, by weight, large stones. are required. All other soils are rated as an improbable source. Coarse This table also gives for each soil the restrictive fragments of soft bedrock, such as shale and siltstone, are features that affect drainage, irrigation, terraces and not considered to be sand and gravel. diversions, and grassed waterways. Topsoil is used to cover an area so that vegetation Pond reservoir areas hold water behind a dam or can be established and maintained. The upper 40 inches embankment. Soils best suited to this use have low of a soil is evaluated for use as topsoil. Also evaluated is seepage potential in the upper 60 inches. The seepage the reclamation potential of the borrow area. potential is determined by the permeability of the soil and Plant growth is affected by toxic material and by such the depth to fractured bedrock or other permeable material. properties as soil reaction, available water capacity, and Excessive slope can affect the storage capacity of the fertility. The ease of excavating, loading, and spreading is reservoir area. affected by rock fragments, slope, a water table, soil texture, Embankments, dikes, and levees are raised structures of and thickness of suitable material. Reclamation of the soil material, generally less than 20 feet high, constructed to borrow area is affected by the slope, a water table, rock impound water or to protect land against overflow. In this fragments, bedrock, and toxic material. table, the soils are rated as a source of material for Soils rated good have friable, loamy material to a depth embankment fill. The ratings apply to the soil material below of at least 40 inches. They are free of stones and cobbles, the surface layer to a depth of about 5 feet. It is assumed have little or no gravel, and have slopes of less than 8 that soil layers will be uniformly mixed and compacted percent. They are low in content of soluble salts, are during construction. naturally fertile or respond well to fertilizer, and are not so The ratings do not indicate the ability of the natural soil wet that excavation is difficult. to support an embankment. Soil properties to a depth even Soils rated fair are sandy soils, loamy soils that have a more than the height of the embankment can affect relatively high content of clay, soils that have only 20 to 40 performance and safety of the embankment. Generally, inches of suitable material, soils that have an appreciable deeper onsite investigation is needed to determine these amount of gravel, stones, or soluble salts, or soils that have properties. slopes of 8 to 15 percent. The soils are not so wet that Soil material in embankments must be resistant to excavation is difficult. seepage, piping, and erosion and have favorable Soils rated poor are very sandy or clayey, have less than compaction characteristics. Unfavorable features include 20 inches of suitable material, have a large amount of less than 5 feet of suitable material and a high content of gravel, stones, or soluble salts, have slopes of more than 15 stones or boulders, organic matter, or salts or sodium. A percent, or have a seasonal high water table at or near the high water table affects the amount of usable material. It surface. also affects trafficability. The surface layer of most soils generally is preferred for Drainage is the removal of excess surface and topsoil because of its organic matter content. subsurface water from the soil. How easily and effectively the soil is drained depends on the depth to bedrock, to a cemented pan, or to other layers that affect the rate of water movement; permeability; depth to a the root zone, the amount of salts or sodium, and soil high water table or depth of standing water if the soil is reaction. subject to ponding; slope; susceptibility to flooding; Terraces and diversions are embankments or a subsidence of organic layers; and potential frost action. combination of channels and ridges constructed across a Excavating and grading and the stability of ditchbanks are slope to control erosion and conserve moisture by affected by depth to bedrock or to a cemented pan, large intercepting runoff. Slope, wetness, large stones, and stones, slope, and the hazard of cutbanks caving. The depth to bedrock or to a cemented pan affect the productivity of the soil after drainage is adversely affected construction of terraces and diversions. A restricted rooting by extreme acidity or by toxic substances in the root zone, depth, a severe hazard of soil blowing or water erosion, an such as salts, sodium, or sulfur. Availability of drainage excessively coarse texture, and restricted permeability outlets is not considered in the ratings. adversely affect maintenance. Irrigation is the controlled application of water to Grassed waterways are natural or constructed supplement rainfall and support plant growth. The design channels, generally broad and shallow, that conduct and management of an irrigation system are affected by surface water to outlets at a nonerosive velocity. Large depth to the water table, the need for drainage, flooding, stones, wetness, slope, and depth to bedrock or t9 a available water capacity, the rate of water intake, cemented pan affect the construction of grassed permeability, erosion hazard, and slope. The construction of waterways. A hazard of soil blowing, low available water a system is affected by large stones and depth to bedrock capacity, restricted rooting depth, toxic substances such as or to a cemented pan. The performance of a system is salts or sodium, and restricted permeability adversely affected by the thickness of affect the growth and maintenance of the grass after construction. Soil Properties

Data relating to soil properties are collected during the percent sand. If the content of particles coarser than sand course of the soil surrey. The data and the estimates of is as much as 15 percent, an appropriate modifier is added, soil and water features listed in tables are explained on the for example, "gravelly." Textural terms are defined in the following pages. "Glossary." Soil properties are determined by field examination of the Classification of the soils is determined according to soils and by laboratory index testing of some benchmark the system adopted by the American Association of State soils. Established standard procedures are followed. During Highway and Transportation Officials (1, 18) and the the survey, many shallow borings are made and examined Unified soil classification system (2, 18). to identify and classify the soils and to delineate them on the The Unified system classifies soils according to soil maps. Samples are taken from some typical profiles and properties that affect their use as construction material. tested in the laboratory to determine grain-size distribution, Soils are classified according to grain-size distribution of plasticity, and compaction characteristics. the fraction less than 3 inches in diameter and according to Estimates of soil properties are based on field plasticity index, liquid limit, and organic matter content. examinations, on laboratory tests of samples from the Sandy and gravelly soils are identified as GW, GP, GM, survey area, and on laboratory tests of samples of similar GC, SW, SP, SM, and SC; silty and clayey soils as ML, CL, soils in nearby areas. Tests verify field observations, verify OL, MH, CH, and OH; and highly organic soils as PT. Soils properties that cannot be estimated accurately by field exhibiting engineering properties of two groups can have a observation, and help to characterize key soils. dual classification, for example, SP-SM. The estimates of soil properties shown in the tables The AASHTO system classifies soils according to those include the range of grain-size distribution and Atterberg properties that affect roadway construction and limits, the engineering classification, and the physical and maintenance. In this system, the fraction of a mineral soil chemical properties of the major layers of each soil. that is less than 3 inches in diameter is classified in one of Pertinent soil and water features also are given. seven groups from A-1 through A-7 on the basis of grain-size distribution, liquid limit, and plasticity index. Soils Engineering Index Properties in group A-1 are coarse grained and low in content of fines (silt and clay). At the other extreme, soils in group A-7 are Table 13 gives estimates of the engineering fine grained. Highly organic soils are classified in group A-8 classification and of the range of index properties for the on the basis of visual inspection. major layers of each soil in the survey area. Most soils Rock fragments larger than 3 inches in diameter are have layers of contrasting properties within the upper 5 indicated as a percentage of the total soil on a dry-weight or 6 feet. basis. The percentages are estimates determined mainly Depth to the upper and lower boundaries of each layer by converting volume percentage in the field to weight is indicated. The range in depth and information on other percentage. properties of each layer are given for each taxonomic Percentage (of soil particles) passing designated sieves unit under "Taxonomic Units and Their Morphology." is the percentage of the soil fraction less than 3 inches in Texture is given in the standard terms used by the U.S. diameter based on an ovendry weight. The sieves, Department of Agriculture. These terms are defined numbers 4, 10, 40, and 200 (USA Standard Series), have according to percentages of sand, silt, and clay in the openings of 4.76, 2.00, 0.420, and 0.074 millimeters, fraction of the soil that is less than 2 millimeters in respectively. Estimates are based on laboratory tests of diameter. "Loam," for example, is soil that is 7 to 27 soils sampled in the survey area and in nearby areas and percent clay., 28 to 50 percent silt, and less than 52 on estimates made in the field. Liquid limit and plasticity index (Atterberg limits) indicate the plasticity characteristics of a soil. The saturated. They are based on soil characteristics observed estimates are based on test data from the survey area or in the field, particularly structure, porosity, and texture. from nearby areas and on field examination. Permeability is considered in the design of soil drainage The estimates of grain-size distribution, liquid limit, and systems, septic tank absorption fields, and construction plasticity index are rounded to the nearest 5 percent. where the rate of water movement under saturated Thus, if the ranges of gradation and Atterberg limits conditions affects behavior. extend a marginal amount (1 or 2 percentage points) Available water capacity refers to the quantity of water across classification boundaries, the classification in the that the soil is capable of storing for use by plants. The marginal zone is omitted in the table. capacity for water storage is given in inches of water per inch of soil for each major soil layer. The capacity varies, Physical and Chemical Properties depending on soil properties that affect the retention of water and the thickness of the root zone. The most Table 14 shows estimates of some characteristics and important properties are the content of organic matter, soil features that affect soil behavior. These estimates are texture, bulk density, and soil structure. Available water given for the major layers of each soil in the survey area. capacity is an important factor in the choice of plants or The estimates are based on field observations and on test crops to be grown and in the design and management of data for these and similar soils. irrigation systems. Available water capacity is not an Depth to the upper and lower boundaries of each estimate of the quantity of water actually available to plants layer is indicated. The range in depth and information on at any given time. other properties of each layer are given for each Soil reaction is a measure of acidity or alkalinity and is taxonomic unit under "Taxonomic Units and Their expressed as a range in pH values. The range in pH of Morphology." each major horizon is based on many field tests. For many Clay as a soil separate consists of mineral soil particles soils, values have been verified by laboratory analyses. Soil that are less than 0.002 millimeter in diameter. In this table, reaction is important in selecting crops and other plants, in the estimated clay content of each major soil layer is given evaluating soil amendments for fertility and stabilization, as a percentage, by weight, of the soil material that is less and in determining the risk of corrosion. than 2 millimeters in diameter. Shrink -swell potential is the potential for volume change The amount and kind of clay greatly affect the fertility in a soil with a loss or gain in moisture. Volume change and physical condition of the soil. They determine the ability occurs mainly because of the interaction of clay minerals of the soil to adsorb cations and to retain moisture. They with water and varies with the amount and type of clay influence shrink -swell potential, permeability, plasticity, the minerals in the soil. The size of the load on the soil and the ease of soil dispersion, and other soil properties. The magnitude of the change in soil moisture content influence amount and kind of clay in a soil also affect tillage and the amount of swelling of soils in place. Laboratory earth-moving operations. measurements of swelling of undisturbed clods were made Moist bulk density is the weight of soil (ovendry) per unit for many soils. For others, swelling was estimated on the volume. Volume is measured when the soil is at field basis of the kind and amount of clay minerals in the soil and moisture capacity; that is, the moisture content is at 1/s bar on measurements of similar soils. moisture tension. Weight is determined after drying the soil If the shrink-swell potential is rated moderate to very at 105 degrees C. In this table, the estimated moist bulk high, shrinking and swelling can cause damage to density of each major soil horizon is expressed in grams per buildings, roads, and other structures. Special design cubic centimeter of soil material that is less than 2 commonly is needed. millimeters in diameter. Bulk density data are used to Shrink-swell potential classes are based on the change compute shrink-swell potential, available water capacity, in length of an unconfined clod as moisture content is total pore space, and other soil properties. The moist bulk increased from air-dry to field capacity. The change is density of a soil indicates the pore space available for water based on the soil fraction less than 2 millimeters in and roots. A bulk density of more than 1.6 can restrict water diameter. The classes are low, a change of less than 3 storage and root penetration. Moist bulk density is percent; moderate, 3 to 6 percent; and high, more than 6 influenced by texture, kind of clay, content of organic matter, percent. Very high, more than 9 percent, is sometimes and soil structure. used. Permeability refers to the ability of a soil to transmit Erosion factor K indicates the susceptibility of a soil to water or air. The estimates indicate the rate of downward sheet and rill erosion. Factor K is one of six factors used movement of water when the soil is in the Universal Soil Loss Equation (USLE) to predict the average rate of soil loss by sheet and rill potential, soils that have a permanent high water table, erosion in tons per acre per year. The estimates are soils that have a claypan or clay layer at or near the based primarily on percentage of silt, very fine sand, surface, and soils that are shallow over nearly impervious sand, and organic matter (as much as 4 percent) and on material. These soils have a very slow rate of water soil structure and permeability. The estimates are transmission. modified by the presence of rock fragments. Values of K Flooding, the temporary covering of the soil surface by range from 0.02 to 0.69. The higher the value, the more flowing water, is caused by overflow from streams, by susceptible the soil is to sheet and rill erosion. runoff from adjacent slopes, or by inflow from high tides. Erosion factor T is an estimate of the maximum Shallow water standing or flowing for short periods after average rate of soil erosion by wind or water that can rainfall or snowmelt is not considered to be flooding. occur without affecting crop productivity over a sustained Standing water in swamps and marshes or in closed period. The rate is in tons per acre per year. depressional areas is considered to be ponding. Organic matter is the plant and animal residue in the soil Table 15 gives the frequency and duration of flooding at various stages of decomposition. In table 14, the and the time of year when flooding is most likely to occur. estimated content of organic matter is expressed as a Frequency, duration, and probable dates of occurrence percentage, by weight, of the soil material that is less than are estimated. Frequency is expressed as none, rare, 2 millimeters in diameter. occasional, and frequent. None means that flooding is not The content of organic matter in a soil can be maintained probable, rare that it is unlikely but is possible under unusual or increased by returning crop residue to the soil. Organic weather conditions (the chance of flooding in any year is 0 to matter affects the available water capacity, infiltration rate, 5 percent), occasional that it occurs infrequently under and tilth. It is a source of nitrogen and other nutrients for normal weather conditions (the chance of flooding in any crops. year is 5 to 50 percent), and frequent that it occurs often under normal weather conditions (the chance of flooding in Water Features any year is more than 50 percent). Duration is expressed as very brief (less than 2 days), Table 15 gives estimates of various water features. brief (2 to 7 days), long (7 days to 1 month), and very long The estimates are used in land use planning that involves (more than 1 month). The time of year that flooding is most engineering considerations. likely to occur is expressed in months. About two-thirds to Hydrologic soil groups are used to estimate runoff from three-fourths of all flooding occurs during the stated period. precipitation. Soils not protected by vegetation are The information on flooding is based on evidence in the assigned to one of four groups. They are grouped soil profile, namely thin strata of gravel, sand, silt, or clay according to the infiltration of water when the soils are deposited by floodwater; irregular decrease in organic matter thoroughly wet and receive precipitation from long-duration content with increasing depth; and absence of distinctive storms. horizons that form in soils that are not subject to flooding. The four hydrologic soil groups are: Also considered are local information about the extent Group A. Soils having a high infiltration rate (low runoff and level of flooding and the relation of each soil on the potential) when thoroughly wet. These consist mainly of landscape to historic floods. Information on the extent of deep, well drained to excessively drained sands or gravelly flooding based on soil data is less specific than that sands. These soils have a high rate of water transmission. provided by detailed engineering surveys that delineate Group B. Soils having a moderate infiltration rate flood-prone areas at specific flood frequency levels. when thoroughly wet. These consist chiefly of moderately High water table (seasonal) is the highest level of a deep or deep, moderately well drained or well drained saturated zone in the soil in most years. The depth to a soils that have moderately fine texture to moderately seasonal high water table applies to undrained soils. The coarse texture. These soils have a moderate rate of estimates are based mainly on the evidence of a saturated water transmission. zone, namely grayish colors or mottles in the soil. Indicated Group C. Soils having a slow infiltration rate when in table 15 are the depth to the seasonal high water table; thoroughly wet. These consist chiefly of soils having a layer the kind of water table-that is, perched or apparent; and the that impedes the downward movement of water or soils of months of the year that moderately fine texture or fine texture. These soils have a slow rate of water transmission. Group D. Soils having a very slow infiltration rate (high runoff potential) when thoroughly wet. These consist chiefly of clays that have a high shrink -swell the water table usually is highest. A water table that is inches thick if it is discontinuous or fractured. Such a seasonally high for less than 1 month is not indicated in the pan is so thick or massive that blasting or special table. equipment is needed in excavation. An apparent water table is a thick zone of free water in Potential frost action is the likelihood of upward or lateral the soil. It is indicated by the level at which water stands in expansion of the soil caused by the formation of segregated an uncased borehole after adequate time is allowed for ice lenses (frost heave) and the subsequent collapse of the adjustment in the surrounding soil. A perched water table is soil and loss of strength on thawing. Frost action occurs water standing above an unsaturated zone. In places an when moisture moves into the freezing zone of the soil. upper, or perched, water table is separated from a lower Temperature, texture, density, permeability, content of water table by a dry zone. organic matter, and depth to the water table are the most Two numbers in the column showing depth to the water important factors considered in evaluating the potential for table indicate the normal range in depth to a saturated zone. frost action. It is assumed that the soil is not insulated by Depth is given to the nearest half foot. The first numeral in vegetation or snow and is not artificially drained. Silty and the range indicates the highest water level. A plus sign highly structured, clayey soils that have a high water table in preceding the range in depth indicates that the water table winter are the most susceptible to frost action. Well drained, is above the surface of the soil. "More than 6.0" indicates very gravelly, or very sandy soils are the least susceptible. that the water table is below a depth of 6 feet or that it is Frost heave and low soil strength during thawing cause within a depth of 6 feet for less than a month. damage mainly to pavements and other rigid structures. Risk of corrosion pertains to potential soil-induced Soil Features electrochemical or chemical action that dissolves or weakens uncoated steel or concrete. The rate of corrosion Table 16 gives estimates of various soil features. The of uncoated steel is related to such factors as soil moisture, estimates are used in land use planning that involves particle-size distribution, acidity, and electrical conductivity engineering considerations. of the soil. The rate of corrosion of concrete is based mainly Depth to bedrock is given if bedrock is within a depth of 5 on the sulfate and sodium content, texture, moisture feet. The depth is based on many soil borings and on content, and acidity of the soil. Special site examination and observations during soil mapping. The rock is specified as design may be needed if the combination of factors creates either soft or hard. If the rock is soft or fractured, a severe corrosion environment. The steel in installations excavations can be made with trenching machines, that intersect soil boundaries or soil layers is more backhoes, or small rippers. If the rock is hard or massive, susceptible to corrosion than steel in installations that are blasting or special equipment generally is needed for entirely within one kind of soil or within one soil layer. excavation. For uncoated steel, the risk of corrosion., expressed as A cemented pan is a cemented or indurated subsurface low, moderate, or high, is based on soil drainage class, layer at a depth of 5 feet or less. Such a pan causes total acidity, electrical resistivity near field capacity, and difficulty in excavation. Pans are classified as thin or thick. electrical conductivity of the saturation extract. A thin pan is one that is less than 3 inches thick if For concrete, the risk of corrosion also is expressed as continuously indurated or less than 18 inches thick if low, moderate, or high. It is based on soil texture, acidity, discontinuous or fractured. Excavations can be made by and amount of sulfates in the saturation extract. trenching machines, backhoes, or small rippers. A thick pan is one that is more than 3 inches thick if continuously indurated or more than 18 Classification of the Soils

The system of soil classification used by the National on the basis of physical and chemical properties and other Cooperative Soil Survey has six categories (26). Beginning characteristics that affect management. Generally, the with the broadest, these categories are the order, suborder, properties are those of horizons below plow depth where great group, subgroup, family, and series. Classification is there is much biological activity. Among the properties and based on soil properties observed in the field or inferred characteristics considered are particle-size class, mineral from those observations or from laboratory measurements. content, temperature regime, thickness of the root zone, Table 17 shows the classification of the soils in the survey consistence, moisture equivalent, slope, and permanent area. The categories are defined in the following cracks. A family name consists of the name of a subgroup paragraphs. preceded by terms that indicate soil properties. An example ORDER. Ten soil orders are recognized. The is fine-silty, mixed, nonacid, Typic Cryaquepts. differences among orders reflect the dominant soil- SERIES. The series consists of soils that have similar forming processes and the degree of soil formation. horizons in their profile. The horizons are similar in color, Each order is identified by a word ending in sol. An texture, structure, reaction, consistence, mineral and example is Inceptisol. chemical composition, and arrangement in the profile. The SUBORDER. Each order is divided into suborders texture of the surface layer or of the substratum can differ primarily on the basis of properties that influence soil within a series. genesis and are important to plant growth or properties that reflect the most important variables within the orders. Taxonomic Units and Their Morphology The last syllable in the name of a suborder indicates the order. An example is Aquept (Aqu, meaning water, plus In this section, each taxonomic unit recognized in the ept, from Inceptisol). survey area is described. The descriptions are arranged in GREAT GROUP. Each suborder is divided into great alphabetic order. groups on the basis of close similarities in kind, Characteristics of the soil and the material in which it arrangement, and degree of development of pedogenic formed are identified for each unit. A pedon, a small horizons; soil moisture and temperature regimes; and base three-dimensional area of soil, that is typical of the unit in status. Each great group is identified by the name of a the survey area is described. The detailed description of suborder and by a prefix that indicates a property of the each soil horizon follows standards in the "Soil Survey soil. An example is Cryaquepts (Cry, meaning cold Manual" (23). Many of the technical terms used in the temperatures, plus aquept, the suborder of the Inceptisols descriptions are defined in "Soil Taxonomy" (26). Unless that has an aquic moisture regime). otherwise stated, colors in the descriptions are for moist soil. SUBGROUP. Each great group has a typic subgroup. Following the pedon description is the range of important Other subgroups are intergrades or extragrades. The typic is characteristics of the soils in the unit. the central concept of the great group; it is not necessarily The map units of each taxonomic unit are described in the most extensive. Intergrades are transitions to other the section "Detailed Soil Map Units." orders, suborders, or great groups. Extragrades have some properties that are not representative of the great group but Abegg Series do not indicate transitions to any other known kind of soil. Each subgroup is identified by one or more adjectives The Abegg series consists of very deep, well drained preceding the name of the great group. The adjective Typic soils on alluvial fans. These soils formed in alluvium and identifies the subgroup that typifies the great group. An colluvium derived from altered sedimentary and volcanic example is Typic Cryaquepts. rock. Slopes are 2 to 12 percent. The mean FAMILY. Families are established within a subgroup annual precipitation is about 35 inches, and the mean plastic; few fine, medium, and coarse roots; common annual temperature is about 50 degrees F. fine and very fine irregular pores; continuous distinct Typical pedon of Abegg gravelly loam, 7 to 12 brown (7.5YR 5/4) clay films; 50 percent gravel and percent slopes, about 5 miles southwest of Applegate 20 percent cobbles; moderately acid (pH 5.8); clear Store on the east side of Thompson Creek Road; about wavy boundary. 2,700 feet north and 1,160 feet west of the southeast Bt3-52 to 66 inches; yellowish brown (10YR 5/4) extremely corner of sec. 7, T. 39 S., R. 4 W. gravelly clay loam, very pale brown (10YR 7/3, 7/4) dry; moderate medium and fine subangular blocky Oi-1/2 inch to 0; twigs, needles, and leaves. structure; hard, friable, slightly sticky and slightly A1-0 to 5 inches; very dark grayish brown (10YR 3/2) plastic; few fine and medium roots; common fine and gravelly, loam, light brownish gray (10YR 6/2) dry; very fine irregular pores; continuous distinct strong strong medium and fine granular structure; soft, brown (7.5YR 5/6) clay films; 50 percent gravel and friable, nonsticky and nonplastic; common fine and 20 percent cobbles; moderately acid (pH 5.8). very fine roots; many very fine, fine, and medium irregular pores; 25 percent gravel and 5 percent The depth to bedrock is 60 inches or more. The cobbles; slightly acid (pH 6.4); abrupt smooth particle-size control section contains 40 to 70 percent boundary. rock fragments and 25 to 35 percent clay. A2-5 to 13 inches; very dark grayish brown (10YR 3/2) very The A horizon has hue of 10YR or 7.5YR; value of 3 or 4 gravelly loam, light brownish gray (10YR 6/2) dry; moist, 3 to 7 dry; and chroma of 2 to 4 moist and dry. The Bt moderate fine and very fine subangular blocky horizon has hue of 10YR or 7.5YR; value of 3 to 5 moist, 4 structure; soft, friable, nonsticky and nonplastic; to 7 dry; and chroma of 3 to 6 moist and dry. It is very common fine and very fine roots; many medium, fine, gravelly clay loam, very gravelly loam, extremely gravelly and very fine irregular pores; 45 percent gravel and 10 clay loam, extremely gravelly loam, or extremely cobbly clay percent cobbles; slightly acid (pH 6.4); abrupt smooth loam. Some pedons have a C horizon below a depth of 40 boundary. inches. This horizon is very gravelly sandy loam, extremely AB-13 to 22 inches; brown (10YR 4/3) very gravelly loam, gravelly loamy sand, or extremely cobbly sandy loam. very pale brown (10YR 7/3) dry; moderate fine and very fine subangular blocky structure; slightly hard, Abin Series friable, nonsticky and nonplastic; few fine and medium roots; many fine and very fine irregular The Abin series consists of very deep, moderately well pores; 45 percent gravel and 10 percent cobbles; drained soils on flood plains. These soils formed in moderately acid (pH 6.0); clear smooth boundary. alluvium. Slopes are 0 to 3 percent. The mean annual BA-22 to 31 inches; dark yellowish brown (10YR 4/4) precipitation is about 24 inches, and the mean annual extremely gravelly loam, very pale brown (10YR 7/3) temperature is about 53 degrees F. dry; moderate fine and very fine subangular blocky Typical pedon of Abin silty clay loam, 0 to 3 percent structure; slightly hard, friable, nonsticky and slopes, about 2 miles southwest of Eagle Point; about 150 nonplastic; few fine and medium roots; common fine feet east and 50 feet south of the northwest corner of sec. and very fine irregular pores; few faint patchy clay films; 9, T. 36 S., R. 1 W. 60 percent gravel and 10 percent cobbles; moderately acid (pH 5.8); clear wavy boundary. Ap-0 to 10 inches; very dark grayish brown (10YR 3/2) silty Bt1-31 to 38 inches; dark yellowish brown (10YR 4/6) clay loam, dark grayish brown (10YR 4/2) dry; weak extremely gravelly loam, very pale brown (10YR 7/3, very fine subangular blocky structure; hard, friable, 7/4) dry; moderate medium and fine subangular blocky sticky and plastic; common very fine and fine roots; structure; hard, friable; nonsticky and nonplastic; few many very fine irregular pores; neutral (pH 6.6); abrupt fine, medium, and coarse roots; common fine and very smooth boundary. fine irregular pores; common faint patchy clay films; 60 A1-10 to 18 inches; very dark grayish brown (10YR 3/2) silty percent gravel and 10 percent cobbles; moderately acid clay loam, dark grayish brown (10YR 4/2) dry; moderate (pH 5.8); clear wavy boundary. fine granular structure; hard, friable, sticky and plastic; Bt2-38 to 52 inches; brown (7.5YR 4/4) extremely gravelly common very fine and fine roots; many irregular pores; clay loam, very pale brown (10YR 7/3, 7/4) dry; neutral (pH 6.8); clear smooth boundary. moderate medium and fine subangular blocky A2-18 to 34 inches; very dark brown (10YR 2/2) silty clay structure; hard, friable, slightly sticky and slightly loam, very dark grayish brown (10YR 3/2) dry; weak medium subangular blocky structure parting to pores; 30 percent gravel and 4 percent cobbles; moderate fine granular; hard, friable, sticky and plastic; strongly acid (pH 5.2); clear smooth boundary. common very fine and fine roots; many very fine BA-8 to 17 inches; yellowish brown (10YR 5/4) gravelly clay irregular pores; neutral (pH 6.8); clear wavy boundary. loam, brownish yellow (10YR 6/6) dry; strong very fine AC-34 to 44 inches; very dark grayish brown (10YR 3/2) and fine subangular blocky structure; slightly hard, silty clay loam, dark grayish brown (10YR 4/2) dry; friable, sticky and plastic; common very fine, fine, weak fine subangular blocky structure parting to medium, and coarse roots; many very fine tubular moderate fine granular; hard, friable, sticky and plastic; pores; 15 percent gravel; strongly acid (pH 5.2); clear common very fine and fine roots; many very fine wavy boundary. irregular pores; neutral (pH 7.0); clear wavy boundary. Bt1-17 to 28 inches; yellowish red (5YR 5/6) gravelly clay C-44 to 65 inches; very dark grayish brown (10YR 3/2) silty loam, strong brown (7.5YR 5/6) dry; strong very fine clay loam, dark grayish brown (10YR 4/2) dry; common and fine subangular blocky structure; hard, firm, sticky fine distinct strong brown (7.5YR 4/6) and yellowish red and plastic; common very fine and fine and few medium (5YR 4/6) mottles; weak fine subangular blocky and coarse roots; many very fine tubular pores; structure; hard, friable, very sticky and plastic; few fine common distinct clay films on -faces of peds and in roots; many very fine tubular pores; neutral (pH 7.0). pores; 15 percent gravel; strongly acid (pH 5.2); gradual wavy boundary. The depth to bedrock is 60 inches or more. The Bt2-28 to 60 inches; strong brown (7.5YR 5/6, 5/8) gravelly particle-size control section contains 35 to 45 percent clay loam, reddish yellow (7.5YR 6/8) dry; moderate clay. The mollic epipedon is 20 to 40 inches thick. The fine and medium subangular blocky structure; slightly soils are characterized by an irregular decrease in content hard, friable, sticky and plastic; few very fine and fine of organic carbon to a depth of 50 inches. roots; common very fine tubular pores; common distinct The upper part of the A horizon has value of 2 or 3 clay films on faces of peds and in pores; 20 percent moist, 3 to 5 dry, and chroma of 1 or 2 moist and dry. The gravel and 5 percent cobbles; strongly acid (pH 5.2). lower part of the A horizon and the AC horizon have value of 2 or 3 moist, 3 to 5 dry, and chroma of 1 to 3 moist and The depth to bedrock is 60 inches or more. The dry. They are silty clay loam, clay, or silty clay. The C particle-size control section contains 20 to 35 percent horizon has value of 3 or 4 moist, 4 or 5 dry, and chroma of clay and 5 to 35 percent rock fragments. 2 or 3 moist and dry. The A horizon has hue of 10YR or 7.5YR; value of 2 to 4 moist, 4 to 6 dry; and chroma of 2 to 4 moist, 3 or 4 dry. Acker Series The Bt horizon has hue of 10YR, 7.5YR, 5YR, or 2.5Y; value of 3 to 5 moist, 4 to 6 dry; and chroma of 3 to 8 moist The Acker series consists of very deep, well drained and dry. It is gravelly clay loam or clay loam. soils on ridges and hillslopes. These soils formed in colluvium and residuum derived from altered sedimentary Agate Series and volcanic rock. Slopes are 12 to 55 percent. The mean annual precipitation is about 50 inches, and the mean The Agate series consists of well drained soils on fan annual temperature is about 48 degrees F. terraces. These soils are moderately deep to a duripan. Typical pedon of Acker gravelly loam, in an area of They formed in stratified alluvium. Slopes are 0 to 15 Norling-Acker complex, 35 to 55 percent south slopes, percent. The mean annual precipitation is about 24 inches, near Waggoner Gap; about 900 feet east and 300 feet and the mean annual temperature is about 53 degrees F. south of the northwest corner of sec. 3, T. 33 S., R. 4 W. Typical pedon of Agate loam, in an area of Agate- Winlo complex, 0 to 5 percent slopes, about 500 feet west Oi-4 inches to 0; bark, leaves, needles, roots, and twigs. and 200 feet south of the intersection of Table Rock Road A-0 to 8 inches; brown (10YR 4/3) gravelly loam, brown and Kirtland Road; about 1,150 feet east and 400 feet (10YR 5/3) dry; strong very fine granular structure; north of the southwest corner of sec. 13, T. 36 S., R. 2 W. soft, very friable, nonsticky and nonplastic; many very fine and common fine, medium, and coarse roots; A-0 to 6 inches; dark brown (10YR 3/3) loam, brown many very fine irregular (10YR 5/3) dry; moderate medium and fine subangular blocky and strong very fine granular structure; hard, friable, slightly sticky and slightly plastic; many very fine and fine roots; 10 percent gravel; slightly acid (pH 6.2); clear smooth boundary. has strata of loam or silt loam. The duripan is indurated in BA-6 to 12 inches; dark yellowish brown (10YR 3/4) clay some parts and is weakly cemented or strongly cemented loam, dark yellowish brown (10YR 4/4) dry; weak in the remaining parts. Cementation is discontinuous and medium subangular blocky structure; hard, friable, weak below the duripan. sticky and plastic; many very fine and fine roots; many very fine irregular pores; 10 percent gravel; slightly acid Alcot Series (pH 6.2); clear smooth boundary. Bw1-12 to 20 inches; dark brown (7.5YR 3/4) clay loam, The Alcot series consists of very deep, somewhat brown (7.5YR 4/4) dry; moderate fine subangular blocky excessively drained soils on plateaus and hillslopes. These structure; hard, friable, sticky and plastic; many fine and soils formed in volcanic ash and pumice. Slopes are 1 to very fine roots; common very fine tubular pores; 10 35 percent. The mean annual precipitation is about -45 percent gravel; moderately acid (pH 6.0); clear smooth inches, and the mean annual temperature is about 48 boundary. degrees F. Bw2-20 to 25 inches; dark brown (7.5YR 3/4) clay loam, Typical pedon of Alcot gravelly sandy loam, in an area of brown (7.5YR 4/4) dry; moderate fine subangular blocky Crater Lake-Alcot complex, 1 to 12 percent slopes, within 1 structure; hard, friable, sticky and plastic; few fine roots; mile of Prospect; about 1,500 feet east and 1,100 feet south common very fine tubular pores; 10 percent gravel; of the northwest corner of sec. 32, T. 32 S., R. 3 E. moderately acid (pH 5.8); abrupt smooth boundary. 2Bqm-25 to 30 inches; yellowish red (5YR 4/6) and red Oi-2 inches to 0; needles, twigs, and moss. (2.5YR 4/6) duripan, yellowish red (5YR 5/6) and A-0 to 4 inches; brown (10YR 4/3) gravelly sandy loam, pale reddish yellow (5YR 6/6) dry; massive; nearly brown (10YR 6/3) dry; weak fine granular structure; soft, continuous, cemented silica laminae; common fine very friable, nonsticky and nonplastic; common very black stains; 40 percent gravel and 20 percent cobbles; fine, fine, medium, and coarse roots; many very fine clear smooth boundary. irregular pores; 20 percent gravel and 5 percent 2C1-30 to 49 inches; light olive brown (2.5YR 5/4) extremely cobbles; slightly acid (pH 6.4); abrupt smooth boundary. gravelly coarse sandy loam, very pale brown (10YR 7/4) Bw-4 to 11 inches; brown (7.5YR 4/4) gravelly sandy loam, and yellow (10YR 7/6) dry; massive; slightly hard, very light yellowish brown (10YR 6/4) dry; weak fine friable, nonsticky and nonplastic; discontinuous, weakly subangular blocky structure; soft, very friable, nonsticky cemented laminae or rock fragments; 55 percent gravel and nonplastic; common very fine, fine, medium, and and 25 percent cobbles; neutral (pH 6.6); gradual coarse roots; many very fine irregular pores; 20 percent smooth boundary. gravel and 10 percent cobbles; moderately acid (pH 2C2-49 to 62 inches; light olive brown (2.5YR 5/4) extremely 5.6); abrupt wavy boundary. gravelly coarse sandy loam, pale yellow (2.5YR 7/4) C1-11 to 44 inches; dark yellowish brown (10YR 4/6) very dry; massive; slightly hard, very friable, nonsticky and cobbly sandy loam, light yellowish brown (10YR 6/4) nonplastic; 55 percent gravel and 25 percent cobbles; dry; massive; soft, very friable, nonsticky and neutral (pH 6.6). nonplastic; common very fine, fine, medium, and coarse roots; many very fine irregular pores; 25 percent gravel The depth to a duripan is 20 to 30 inches. The depth to and 30 percent cobbles; moderately acid (pH 5.6); bedrock is 60 inches or more. The particle-size control abrupt wavy boundary. section contains 10 to 30 percent rock fragments and 18 to C2-44 to 60 inches; olive brown (2.5Y 4/4) very cobbly 35 percent clay. sandy loam, light gray (2.5Y 7/2) dry; massive; slightly The A horizon has hue of 10YR or 7.5YR; value of 3 or 4 hard, friable, nonsticky and nonplastic; few very fine, moist, 4 or 5 dry; and chroma of 2 to 4 moist and dry. The fine, and medium roots; common very fine irregular Bw horizon has hue of 7.5YR or 5YR and value of 3 or 4 pores; 25 percent gravel and 30 percent cobbles; moist, 4 to 6 dry. It generally is clay loam, loam, or gravelly moderately acid (pH 5.6). loam. The 2C horizon has hue of 2.5YR to 5YR; value of 4 to 6 moist, 6 or 7 dry; and chroma of 4 or 5 moist, 4 to 6 The depth to bedrock is 60 inches or more. The solum is dry. It generally is extremely gravelly coarse sandy loam or 10 to 25 inches thick. The profile consists of volcanic ash extremely gravelly loamy sand and contains 40 to 60 and gravel- and cobble-sized pumice fragments. The percent gravel and 10 to 30 percent cobbles. In some particle-size control section contains 15 to 35 percent pedons it gravel-sized pumice fragments and 20 to 35 percent cobble-sized pumice fragments. It has a bulk density of 0.75 to 0.90 gram per cubic centimeter. particle-size control section contains 12 to 18 percent The A horizon has hue of 7.5YR or 10YR; value of 3 or 4 clay and 15 to 35 percent rock fragments. moist, 5 or 6 dry; and chroma of 2 to 4 moist and dry. The The A horizon has hue of 10YR or 7.5YR; value of 2 or Bw horizon has hue of 7.5YR or 10YR; value of 3 to 5 3 moist, 4 or 5 dry; and chroma of 2 or 3 moist and dry. moist, 6 or 7 dry; and chroma of 3 or 4 moist and dry. The C The Bw horizon has hue of 10YR or 7.5YR; value of 3 or 4 horizon has hue of 7.5YR, 10YR, or 2.5Y; value of 4 or 5 moist, 4 to 6 dry; and chroma of 2 or 3 moist and dry. moist, 6 or 7 dry; and chroma of 3 to 6 moist, 2 to 4 dry. It is very cobbly sandy loam, very cobbly loamy sand, or Atring Series extremely cobbly loamy sand. Stratification is common below a depth of 40 inches. The Atring series consists of moderately deep, well drained soils on hillslopes. These soils formed in colluvium Aspenlake Series derived from altered sedimentary and volcanic rock. Slopes are 50 to 80 percent. The mean annual precipitation is about The Aspenlake series consists of well drained soils on 50 inches, and the mean annual temperature is about 48 alluvial fans. These soils are moderately deep to a duripan. degrees F. They formed in alluvium derived from andesite and basalt. Typical pedon of Atring very gravelly loam, in an area of Slopes are 1 to 12 percent. The mean annual precipitation Kanid-Atring very gravelly loams, 50 to 80 percent north is about 30 inches, and the mean annual temperature is slopes, about 13.5 miles north of Wimer; about 1,400 feet about 42 degrees F. west and 2,450 feet south of the northeast corner of sec. 2, Typical pedon of Aspenlake stony loam, in an area of T. 33 S., R. 4 W. Aspen lake-Whiteface complex, 1 to 12 percent slopes, north of Aspen Lake; about 2,200 feet west and 1,600 feet Oi-1 inch to 0; needles, leaves, twigs, and roots. south of the northeast corner of sec. 17, T. 37 S., R. 7 E. A-0 to 7 inches; very dark brown (10YR 2/2) very gravelly loam, dark grayish brown (10YR 4/2) dry; moderate A1-0 to 4 inches; dark brown (7.5YR 3/2) stony loam, brown very fine granular structure; slightly hard, very friable, (10YR 5/3) dry; moderate fine granular structure; soft, nonsticky and nonplastic; many very fine, fine, and friable, slightly sticky and slightly plastic; many very medium and common coarse roots; many very fine and fine, common fine and medium, and few coarse roots; fine irregular pores; 45 percent gravel and 5 percent many very fine irregular pores; 10 percent gravel, 5 cobbles; moderately acid (pH 5.6); abrupt smooth percent cobbles, and 5 percent stones; moderately acid boundary. (pH 5.6); clear smooth boundary. Bw1-7 to 24 inches; brown (10YR 4/3) very gravelly loam, A2-4 to 10 inches; dark brown (7.5YR 3/3) gravelly loam, yellowish brown (10YR 5/4) dry; moderate very fine and brown (10YR 5/3) dry; moderate very fine subangular fine subangular blocky structure; slightly hard, very blocky structure; slightly hard, friable, slightly sticky and friable, slightly sticky and slightly plastic; common very slightly plastic; many very fine, common fine and fine, fine, medium, and coarse roots; many fine irregular medium, and few coarse roots; many very fine irregular pores; 30 percent gravel and 5 percent cobbles; pores; 10 percent gravel and 5 percent cobbles; moderately acid (pH 5.6); gradual wavy boundary. moderately acid (pH 5.6); abrupt wavy boundary. Bw2-24 to 40 inches; yellowish brown (10YR 5/4) very Bw-10 to 26 inches; dark brown (7.5YR 3/3) gravelly loam, gravelly loam, light yellowish brown (10YR 6/4) dry; pale brown (10YR 6/3) dry; moderate very fine and fine moderate very fine and fine subangular blocky angular blocky structure; slightly hard, firm, slightly structure; slightly hard, very friable, slightly sticky and sticky and slightly plastic; common very fine and few slightly plastic; common very fine, fine, medium, and fine, medium, and coarse roots; many very fine irregular coarse roots; many very fine irregular pores; 35 percent pores; 15 percent gravel and 5 percent cobbles; gravel and 10 percent cobbles; strongly acid (pH 5.4); moderately acid (pH 5.8); abrupt wavy boundary. gradual wavy boundary. 2Bqm-26 to 60 inches; .strongly cemented, gravelly duripan. Cr-40 inches; highly fractured, metavolcanic bedrock.

The depth to a strongly cemented duripan is 20 to 40 The depth to bedrock is 20 to 40 inches. The inches. The depth to bedrock is 60 inches or more. The particle-size control section contains 35 to 60 percent rock fragments and 15 to 30 percent clay. The A horizon has hue of 10YR or 7.5YR; value of 2 to 5 moist, 4 to 7 dry; and chroma of 2 to 4 moist and dry. The Bw horizon has hue of 10YR or 7.5YR; value of Barhiskey Variant 3 to 5 moist, 5 to 7 dry; and chroma of 3 to 6 moist and dry. It is very gravelly loam, very gravelly clay loam, or The Barhiskey Variant consists of very deep, somewhat very gravelly silt loam. poorly drained soils on outwash plains. These soils formed in sandy alluvium mixed with pumice and volcanic ash. Barhiskey Series Slopes are 0 to 3 percent. The mean annual precipitation is about 45 inches, and the mean annual temperature is The Barhiskey series consists of very deep, about 49 degrees F. excessively drained soils on outwash plains. These soils Typical pedon of Barhiskey Variant gravelly loamy sand, formed in sandy alluvium mixed with pumice and volcanic 0 to 3 percent slopes, about 1.5 miles northeast of ash. Slopes are 0 to 3 percent. The mean annual Prospect; about 2,600 feet east and 250 feet north of the precipitation is about 45 inches, and the mean annual southwest corner of sec. 22, T. 32 S., R. 3 E. temperature is about 49 degrees F. Typical pedon of Barhiskey gravelly loamy sand, 0 to 3 Oi-1 inch to 0; needles and twigs. percent slopes, about 4 miles northeast of Prospect; about A1-0 to 3 inches; black (10YR 2/1) gravelly loamy sand, 2,200 feet west and 1,575 feet north of the southeast dark grayish brown (10YR 4/2) dry; moderate fine corner of sec. 14, T. 32 S., R. 3 E. granular structure; loose, very friable, nonsticky and nonplastic; common very fine, fine, and medium roots; Oi-1 inch to 0; needles and twigs. many very fine irregular pores; 20 percent gravel; A-0 to 4 inches; black (10YR 2/1) gravelly loamy sand, dark moderately acid (pH 5.8); abrupt smooth boundary. grayish brown (10YR 4/2) dry; weak fine granular A2-3 to 8 inches; black (10YR 2/1) gravelly loamy sand, structure; soft, very friable, nonsticky and nonplastic; dark grayish brown (10YR 4/2) dry; moderate fine and many very fine and fine and common medium and medium subangular blocky structure; loose, nonsticky coarse roots; many very fine irregular pores; 20 percent and nonplastic; common very fine, fine, and medium gravel; moderately acid (pH 5.6); abrupt smooth roots; common very fine and fine irregular pores; 20 boundary. percent gravel; moderately acid (pH 5.6); abrupt wavy AC-4 to 19 inches; dark brown (10YR 3/3) gravelly sand, boundary. brown (10YR 5/3) dry; single grain; loose, nonsticky and AC-8 to 29 inches; very dark grayish brown (10YR 3/2) nonplastic; common very fine, fine, medium, and coarse gravelly sand, grayish brown (10YR 5/2) dry; common roots; common very fine and fine irregular pores; 25 large prominent strong brown (7.5YR 4/6, 5/6) mottles; percent gravel and 5 percent cobbles; moderately acid weak very fine and fine subangular blocky structure; (pH 6.0); abrupt wavy boundary. loose, nonsticky and nonplastic; few very fine and fine C1-19 to 39 inches; very dark gray (10YR 3/1) gravelly roots; common very fine and fine irregular pores; 25 sand, dark grayish brown (10YR 4/2) dry; single grain; percent gravel; moderately acid (pH 5.8); gradual wavy loose, nonsticky and nonplastic; few roots; common boundary. very fine and fine irregular pores; 20 percent gravel; C-29 to 60 inches; very dark gray (10YR 3/1) gravelly sand, slightly acid (pH 6.4); gradual wavy boundary. grayish brown (10YR 5/2) dry; common large prominent C2-39 to 60 inches; very dark gray (10YR 3/1) gravelly strong brown (7.5YR 4/6, 5/6) mottles; single grain; sand, dark grayish brown (10YR 4/2) dry; single grain; loose, nonsticky and nonplastic; few very fine and fine loose, nonsticky and nonplastic; few roots; common roots; common very fine and fine irregular pores; 30 very fine and fine irregular pores; 30 percent gravel; percent gravel; moderately acid (pH 5.8). moderately acid (pH 5.6). The depth to bedrock is 60 inches or more. The The depth to bedrock is 60 inches or more. The particle-size control section is sand and contains 20 to 35 particle-size control section is sand and contains 20 to 35 percent rock fragments. percent rock fragments. The umbric epipedon is 10 to 20 The A and AC horizons have value of 2 or 3 moist, 4 or 5 inches thick. dry, and chroma of 1 or 2 moist and dry. The C horizon has The A horizon has value of 2 or 3 moist, 4 or 5 dry, and value of 2 to 4 moist, 4 to 6 dry, and chroma of 1 or 2 moist chroma of 1 or 2 moist, 2 or 3 dry. The AC horizon has and dry. value of 4 or 5 dry and chroma of 2 or 3 dry. The C horizon has value of 4 or 5 dry and chroma of 1 or 2 moist. Barron Series

The Barron series consists of very deep, somewhat excessively drained soils on alluvial fans. These soils formed in alluvium derived from granitic rock. Slopes are precipitation is about 45 inches, and the mean annual 0 to 12 percent. The mean annual precipitation is about temperature is about 49 degrees F. 25 inches, and the mean annual temperature is about 52 Typical pedon of Beekman gravelly loam, in an area of degrees F. Beekman-Colestine gravelly loams, 50 to 80 percent north Typical pedon of Barron coarse sandy loam, 0 to 7 slopes, about 3 miles southeast of Wimer; about 1,000 feet percent slopes, about 1.5 miles southwest of Wimer; north and 2,400 feet west of the southeast corner of sec. about 1,650 feet east and 950 feet north of the southwest 25, T. 35 S., R. 4 W. corner of sec. 15, T. 35 S., R. 4 W. A-0 to 5 inches; dark brown (10YR 3/3) gravelly loam, brown A-0 to 6 inches; dark brown (10YR 3/3) sandy loam, brown (10YR 4/3) dry; weak fine and medium granular (10YR 5/3) dry; moderate fine granular structure; soft, structure; soft, friable, slightly sticky and slightly plastic; very friable, nonsticky and nonplastic; many very fine common very fine and fine roots; many very fine and and fine roots; many very fine irregular pores; 2 percent fine irregular pores; 25 percent gravel; slightly acid (pH gravel; strongly acid (pH 5.4); abrupt smooth boundary. 6.5); clear smooth boundary. Bw-6 to 23 inches; brown (10YR 4/3) sandy loam, light AB-5 to 14 inches; dark brown (10YR 3/3) gravelly loam, yellowish brown (10YR 6/4) dry; weak coarse brown (10YR 5/3) dry; weak fine and very fine subangular blocky structure; slightly hard, friable, subangular blocky structure; slightly hard, friable, nonsticky and nonplastic; common very fine and fine slightly sticky and slightly plastic; common medium and roots; many very fine tubular pores; 2 percent gravel; coarse and few fine and very fine roots; many fine moderately acid (pH 5.6); clear wavy boundary. irregular pores; 25 percent gravel; slightly acid (pH 6.2); C1-23 to 37 inches; dark yellowish brown (10YR 4/4) sandy clear wavy boundary. loam, light yellowish brown (10YR 6/4) dry; weak coarse Bw-14 to 28 inches; grayish brown (2.5Y 5/2) extremely prismatic structure parting to weak medium and coarse gravelly loam, light brownish gray (2.5Y 6/2) dry; weak subangular blocky; hard, friable, nonsticky and fine and very fine subangular blocky structure; soft, very nonplastic; few very fine roots; common very fine tubular friable, slightly sticky and slightly plastic; few fine and pores; 2 percent gravel; moderately acid (pH 5.8); very fine roots; many very fine irregular pores;. 70 gradual wavy boundary. percent gravel; slightly acid (pH -6.4); clear wavy C2-37 to 60 inches; brown (10YR 4/3) sandy loam, pale boundary. brown (10YR 6/3) dry; massive; hard, friable, slightly R-28 inches; fractured, metamorphosed sedimentary sticky and nonplastic; few very fine roots; common very bedrock. fine tubular pores; 2 percent gravel; moderately acid (pH 5.6). The depth to bedrock is 20 to 40 inches. The particle-size control section contains 35 to 70 percent The depth to bedrock is 60 inches or more. The rock fragments and 18 to 30 percent clay. particle-size control section contains 8 to 18 percent The A horizon has hue of 10YR or 7.5YR; value of 3 or clay. 4 moist, 4 to 6 dry; and chroma of 2 to 4 moist, 3 or 4 dry. The A horizon has hue of 10YR or 2.5Y; value of 3 or 4 The Bw horizon has hue of 2.5Y, 10YR, or 7.5YR; value of moist, 5 to 7 dry; and chroma of 2 or 3 moist and dry. The 4 or 5 moist, 5 to 7 dry; and chroma of 2 to 4 moist and dry. Bw horizon has hue of 10YR or 2.5Y; value of 4 or 5 moist, It is very gravelly loam, very gravelly clay loam, or 6 or 7 dry; and chroma of 3 to 6 moist, 3 to 5 dry. It is extremely gravelly loam. coarse sandy loam or sandy loam. The C horizon has hue of 10YR or 2.5Y; value of 4 or 5 moist, 6 or 7 dry; and Bly Series chroma of 2 to 6 moist and dry. It is coarse sandy loam or sandy loam. The Bly series consists of very deep, well drained soils on plateaus and hillslopes. These soils formed in sediment Beekman Series weathered from andesite and containing small amounts of volcanic ash. Slopes are 1 to 35 percent. The mean annual The Beekman series consists of moderately deep, well precipitation is about 20 inches, and the mean annual drained soils on hillslopes. These soils formed in colluvium temperature is about 44 degrees F. derived from altered sedimentary and volcanic rock. Slopes Typical pedon of Bly loam, in an area of Bly-Royst are 50 to 80 percent. The mean annual complex, 12 to 35 percent slopes, about 5.5 miles west of Keno; about 1,550 feet south and 2,200 feet east of the northwest corner of sec. 31, T. 39 S., R. 7 E. Oi-3 inches to 0; needles, twigs, and roots. very dark grayish brown (10YR 3/2) dry; weak fine A-0 to 17 inches; very dark brown (10YR 2/2) loam, brown granular structure; soft, very friable, slightly sticky and (10YR 4/3) dry; moderate very fine and fine subangular slightly plastic; many very fine and fine roots; many very blocky structure; soft, very friable, slightly sticky and fine irregular pores; 35 percent gravel; slightly acid (pH slightly plastic; common very fine, fine, medium, and 6.5); clear smooth boundary. coarse roots; common very fine tubular pores; slightly A3-7 to 15 inches; very dark grayish brown (10YR 3/2) very acid (pH 6.2); clear wavy boundary. gravelly loam, dark grayish brown (10YR 4/2) dry; weak Bt1-17 to 36 inches; dark brown (7.5YR 3/3) clay loam, fine granular structure; soft, very friable, slightly sticky yellowish brown (10YR 5/4) dry; moderate very fine and and slightly plastic; many very fine and fine roots; many fine angular blocky structure; hard, friable, sticky and very fine irregular pores; 35 percent gravel; slightly acid plastic; common very fine and few fine, medium, and (pH 6.5); clear smooth boundary. coarse roots; many very fine tubular pores; common BA-15 to 21 inches; dark brown (10YR 3/3) gravelly clay faint clay films on faces of peds and in pores; slightly loam, brown (10YR 4/3) dry; weak fine subangular acid (pH 6.2); clear wavy boundary. blocky structure; slightly hard, friable, sticky and plastic; Bt2-36 to 60 inches; dark yellowish brown (10YR 3/4) clay common fine roots; many very fine irregular and few loam, yellowish brown (10YR 5/4) dry; weak medium very fine tubular pores; 20 percent gravel; slightly acid subangular blocky structure; hard, friable, sticky and (pH 6.5); clear smooth boundary. plastic; few very fine, fine, and medium roots; many very Bt1-21 to 48 inches; dark yellowish brown (10YR 3/4) clay fine tubular pores; few faint clay films on faces of peds loam, dark yellowish brown (10YR 4/4) dry; moderate and in pores; 13 percent gravel; slightly acid (pH 6.2). fine and medium subangular blocky structure; hard, firm, very sticky and very plastic; common fine and The depth to bedrock is 60 inches or more. The medium roots; common very fine tubular pores; particle-size control section contains 27 to 35 percent common distinct clay films on faces of peds and in clay and 10 to 35 percent rock fragments. The mollic pores; 10 percent gravel; slightly acid (pH 6.5); gradual epipedon is 20 to 30 inches thick. wavy boundary. The A horizon has value of 2 or 3 moist, 4 or 5 dry, and Bt2-48 to 65 inches; dark brown (7.5YR 3/4) clay loam, chroma of 2 or 3 moist and dry. The Bt horizon has hue of brown (7.5YR 4/4) dry; moderate fine and medium 10YR or 7.5YR; value of 3 to 5 moist, 5 or 6 dry; and subangular blocky structure; hard, firm, very sticky and chroma of 3 or 4 moist, 2 to 4 dry. It is clay loam or gravelly plastic; few medium roots; common very fine and fine clay loam. tubular pores; few distinct clay films on faces of peds and in pores; 5 percent gravel; slightly acid (pH 6.5). Bogus Series The depth to bedrock is 60 inches or more. The The Bogus series consists of very deep, well drained particle-size control section contains 35 to 45 percent soils on hillslopes. These soils formed in colluvium and clay and 5 to 15 percent rock fragments. The mollic residuum derived from igneous rock. Slopes are 1 to 65 epipedon is 20 to 25 inches thick. percent. The mean annual precipitation is about 25 inches, The A horizon has hue of 10YR or 7.5YR; value of 2 or 3 and the mean annual temperature is about 48 degrees F. moist, 3 or 4 dry; and chroma of 1 to 3 moist and dry. The Typical pedon of Bogus very gravelly loam, 35 to 65 Bt horizon has hue of 10YR or 7.5YR; value of 3 to 5 moist, percent north slopes, about 1 mile southeast of Pilot Rock; 3 to 6 dry; and chroma of 3 to 6 moist and dry. It is clay about 650 feet south and 550 feet west of the northeast loam or clay. corner of sec. 12, T. 41 S., R. 2 E. Booth Series Oi-1 inch to 0; needles, leaves, and twigs. A1-0 to 2 inches; black (10YR 2/1) very gravelly loam, very The Booth series consists of moderately deep, well dark grayish brown (10YR 3/2) dry; weak very fine drained soils on plateaus. These soils formed in colluvium granular structure; soft, very friable, nonsticky and derived from igneous rock. Slopes are 0 to 3 percent. The nonplastic; many very fine and fine roots; many very mean annual precipitation is about 18 inches, and the fine irregular pores; 45 percent gravel; slightly acid (pH mean annual temperature is about 44 degrees F. 6.4); abrupt smooth boundary. Typical pedon of Booth loam, in an area of Booth- A2-2 to 7 inches; black (10YR 2/1) very gravelly loam, Kanutchan Variant complex, 0 to 3 percent slopes; about 150 feet east and 1,850 feet north of the Debenger loams, 1 to 15 percent slopes, about 1.5 miles southwest corner of sec. 11, T. 41 S., R. 6 E. northeast of the community of Sams Valley; about 250 feet south of a logging road; 1,575 feet east and 785 feet south A1-0 to 5 inches; dark brown (7.5YR 3/2) loam, grayish of the northwest corner of sec. 28, T. 35 S., R. 2 W. brown (10YR 5/2) dry; moderate thin to very thick platy structure; slightly hard, very friable, slightly sticky and A-0 to 6 inches; dark brown (7.5YR 3/2) loam, light brown slightly plastic; common very fine and fine roots; (7.5YR 6/4) dry; weak fine subangular blocky structure common fine and medium tubular pores; 5 percent parting to moderate very fine granular; slightly hard, gravel; slightly acid (pH 6.2); abrupt smooth boundary. friable, slightly sticky and slightly plastic; many very fine A2-5 to 15 inches; dark brown (7.5YR 3/2) loam, brown and few medium roots; many irregular pores; neutral (10YR 5/3) dry; moderate fine and medium subangular (pH 6.8); clear smooth boundary. blocky structure; slightly hard, very friable, slightly sticky Bw-6 to 13 inches; dark reddish brown (5YR 3/4) loam, light and slightly plastic; few very fine, fine, and medium brown (7.5YR 6/4) dry; moderate fine subangular blocky roots; common very fine, fine, and medium tubular structure; hard, friable, slightly sticky and slightly plastic; pores; 5 percent gravel; slightly acid (pH 6.4); abrupt common fine and medium roots; many very fine tubular wavy boundary. pores; neutral (pH 6.7); abrupt smooth boundary. 2Bt1-15 to 26 inches; brown (10YR 4/3) clay, brown (10YR Cr-13 inches; saprolitic sandstone; few black (10YR 2/1) 5/3) dry; strong medium prismatic structure; very hard, stains in fractures. very firm, very sticky and very plastic; few very fine roots; common very fine tubular pores; continuous The depth to bedrock and the thickness of the solum are prominent clay films on faces of peds and in pores; 12 to 20 inches. The particle-size control section contains neutral (pH 6.7); clear smooth boundary. 20 to 35 percent clay and 5 to 25 percent rock fragments. 2Bt2-26 to 35 inches; dark yellowish brown (10YR 4/4) clay, The A horizon has hue of 7.5YR or 10YR; value of 3 or 4 light yellowish brown (10YR 6/4) dry; moderate medium moist, 4 to 6 dry; and chroma of 2 to 4 moist. The Bw prismatic structure parting to moderate fine and medium horizon has hue of 5YR, 7.5YR, or 10YR and value of 3 or subangular blocky; hard, very firm, sticky and plastic; 4 moist, 4 to 6 dry. It is loam, clay loam, or gravelly loam. few very fine roots; common very fine tubular pores; continuous prominent clay films on faces of peds and in Bybee Series pores; neutral (pH 6.7); clear smooth boundary. 3Cr-35 to 37 inches; decomposed tuff. 3R-37 inches; tuff. The Bybee series consists of very deep, somewhat poorly drained soils on plateaus and hillslopes. These The depth to bedrock is 20 to 40 inches. The soils formed in colluvium derived from igneous rock. particle-size control section contains 45 to 60 percent Slopes are 1 to 35 percent. The mean annual clay. The content of clay increases by at least 20 percent precipitation is about 40 inches, and the mean annual at the upper boundary of the argillic horizon. The mollic temperature is about 43 degrees F. epipedon is 7 to 15 inches thick. Typical pedon of Bybee loam, in an area of Bybee- The A horizon has hue of 10YR or 7.5YR; value of 2 or Tatouche complex, 12 to 35 percent south slopes, about 3 moist, 3 to 5 dry; and chroma of 1 to 3 moist and dry. The 0.25 mile northeast of Shale City; about 1,525 feet north 2Bt horizon has hue of 7.5YR, 10YR, or 2.5Y; value of 2 to and 450 feet west of the southeast corner of sec. 9, T. 38 4 moist, 3 to 6 dry; and chroma of 2 to 4 moist and dry. It is S., R. 2 E. clay or silty clay. Oi-1/2 inch to 0; needles, leaves, twigs, and roots. Brader Series A1-0 to 4 inches; very dark grayish brown (10YR 3/2) loam, dark brown (10YR 5/2) dry; moderate fine and medium The Brader series consists of shallow, well drained granular structure; slightly hard, friable, slightly sticky soils on knolls and ridges. These soils formed in and slightly plastic; many fine and common medium colluvium derived from sandstone. Slopes are 1 to 40 roots; many irregular pores; 5 percent gravel and 5 percent. The mean annual precipitation is about 24 percent cobbles; slightly acid (pH 6.5); abrupt smooth inches, and the mean annual temperature is about 53 boundary. degrees F. A2-4 to 10 inches; very dark grayish brown (10YR 3/2) Typical pedon of Brader loam, in an area of Brader- clay loam, brown (10YR 5/3) dry; moderate medium pores; slightly acid (pH 6.5); abrupt smooth boundary. subangular blocky structure; slightly hard, friable, sticky C1-10 to 19 inches; very dark grayish brown (10YR 3/2) and plastic; many fine and common medium roots; very gravelly loamy sand, brown (10YR 5/3) dry; single many very fine tubular pores; 5 percent gravel and 5 grain; soft, very friable, nonsticky and nonplastic; many percent cobbles; slightly acid (pH 6.4); abrupt smooth fine irregular pores; 35 percent gravel; slightly acid (pH boundary. 6.5); clear smooth boundary. 2Bw1-10 to 14 inches; brown (10YR 4/3) clay, brown (10YR C2-19 to 60 inches; very dark grayish brown (10YR 3/2) 4/3) dry; weak medium and coarse subangular blocky extremely gravelly coarse sand, dark grayish brown structure; extremely hard, extremely firm, very sticky (10YR 4/2) dry; single grain; loose, nonsticky and and very plastic; few medium and coarse roots; many nonplastic; many fine irregular pores; 50 percent gravel very fine tubular pores; 5 percent gravel and 5 percent and 20 percent cobbles; slightly acid (pH 6.5). cobbles; moderately acid (pH 6.0); gradual wavy boundary. The depth to bedrock is 60 inches or more. The 2Bw2-14 to 38 inches; light yellowish brown (2.5Y 6/4) clay, particle-size control section contains 35 to 80 percent rock variegated light gray (2.5Y 7/2) and light yellowish fragments. It is coarse sand, sand, or loamy sand. The brown (2.5Y 6/4) dry; weak medium and coarse angular mollic epipedon is 10 to 14 inches thick. blocky structure; massive when wet; extremely hard, The A horizon has hue of 10YR or 7.5YR; value of 2 or 3 extremely firm, very sticky and very plastic; few medium moist, 4 or 5 dry; and chroma of 2 or 3 moist and dry. It is and coarse roots; many very fine tubular pores; 5 gravelly sandy loam or sandy loam. The C horizon has hue percent cobbles; moderately acid (pH 6.0); gradual of 10YR or 7.5YR; value of 3 or 4 moist, 4 to 6 dry; and wavy boundary. chroma of 2 to 4 moist and dry. It is extremely gravelly 2C-38 to 60 inches; variegated light yellowish brown (2.5Y coarse sand, very gravelly sand, or very gravelly loamy 6/4) clay, variegated light gray (2.5Y 7/2) and light sand. yellowish brown (2.5Y 6/4) dry; massive; extremely hard, extremely firm, very sticky and very plastic; 5 Campfour Series percent gravel and cobbles; moderately acid (pH 5.6). The Campfour series consists of very deep, well drained The depth to bedrock is 60 inches or more. The soils on plateaus and hillslopes. These soils formed in particle-size control section contains 40 to 55 percent residuum and colluvium derived from igneous rock. Slopes clay and 5 to 25 percent rock fragments. are 1 to 35 percent. The mean annual precipitation is about The A horizon has hue of 10YR or 7.5YR; value of 2 or 23 inches, and the mean annual temperature is about 48 3 moist, 4 or 5 dry; and chroma of 2 or 3 moist and dry. In degrees F. many pedons a stone line is at the lower boundary of this Typical pedon of Campfour loam, in an area of horizon. The 2Bw and 2C horizons have hue of 2.5Y or Campfour-Paragon complex, 1 to 12 percent slopes; 10YR, value of 4 to 7 moist and dry, and chroma of 2 to 4 about 800 feet south and 1,500 feet east of the moist and dry. They are clay or gravelly clay. northwest corner of sec. 1, T. 41 S., R. 5 E.

Camas Series Oi-1 inch to 0; needles and twigs. A-0 to 5 inches; dark reddish brown (5YR 3/2) loam, reddish The Camas series consists of very deep, excessively brown (5YR 4/3) dry; strong very fine granular structure; drained soils on flood plains, These soils formed in gravelly slightly hard, friable, slightly sticky and slightly plastic; alluvium. Slopes are 0 to 3 percent. The mean annual many very fine and common fine, medium, and coarse precipitation is about 30 inches, and the mean annual roots; many very fine irregular pores; 9 percent gravel temperature is about 52 degrees F. and 5 percent cobbles; moderately acid (pH 5.8); clear Typical pedon of Camas sandy loam, 0 to 3 percent smooth boundary. slopes, about 1.5 miles southeast of Lower Table Rock; AB-5 to 21 inches; dark reddish brown (5YR 3/3) loam, about 1,610 feet south and 1,320 feet west of the northeast reddish brown (5YR 4/4) dry; moderate very fine corner of sec. 15, T. 36 S., R. 2 W. subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; many very fine and Ap-0 to 10 inches; dark brown (10YR 3/3) sandy loam, common fine, medium, and coarse roots; many very brown (10YR 5/3) dry; single grain; soft, very friable, fine tubular pores; 9 percent gravel and nonsticky and nonplastic; many fine irregular 5 percent cobbles; moderately acid (pH 5.6); clear wavy irregular pores; 30 percent gravel and 15 percent boundary. cobbles; neutral (pH 6.6); clear smooth boundary. Bt1-21 to 50 inches; dark reddish brown (5YR 3/3) clay Bw1-12 to 20 inches; dark yellowish brown (10YR 4/4) very loam, reddish brown (5YR 4/4) dry; moderate very fine gravelly clay loam, light yellowish brown (10YR 6/4) dry; and fine angular blocky structure; hard, firm, sticky and moderate fine and medium subangular blocky structure; plastic; common very fine and few fine, medium, and hard, friable, slightly sticky and plastic; many very fine coarse roots; common very fine tubular pores; common and fine roots; many irregular pores; 40 percent gravel faint clay films on faces of peds and in pores; 10 and 15 percent cobbles; neutral (pH 6.6); clear wavy percent gravel; moderately acid (pH 5.6); gradual wavy boundary. boundary. Bw2-20 to 31 inches; dark yellowish brown (10YR 4/4) Bt2-50 to 60 inches; dark reddish brown (5YR 3/4) gravelly extremely gravelly loam, light yellowish brown (10YR clay loam, reddish brown (5YR 4/4) dry; moderate very 6/4) dry; moderate fine and medium subangular blocky fine and fine angular blocky structure; hard, firm, sticky structure; hard, friable; slightly sticky and plastic; and plastic; few very fine, fine, and medium roots; common fine roots; many irregular pores; 50 percent common very fine tubular pores; common faint clay gravel and 20 percent cobbles; neutral (pH 6.6); abrupt films on faces of peds and in pores; 15 percent gravel; wavy boundary. moderately . acid (pH 5.6). R-31 inches; fractured, metamorphosed volcanic bedrock.

The depth to bedrock is 60 inches or more. The The depth to bedrock is 20 to 40 inches. The particle-size control section contains 27 to 35 percent particle-size control section contains 35 to 70 percent clay and 5 to 35 percent rock fragments. The mollic rock fragments and 18 to 30 percent clay. epipedon is 20 to 40 inches thick. The A horizon has value of 3 or 4 moist, 4 to 6 dry, and The A horizon has hue of 7.5YR, 5YR, or 2.5YR; value chroma of 2 to 4 moist and dry. The Bw horizon has hue of of 2 or 3 moist; and chroma of 2 or 3 moist, 3 or 4 dry. The 10YR or 7.5YR; value of 4 or 5 moist, 5 or 6 dry; and Bt horizon has hue of 5YR or 2.5YR and chroma of 3 or 4 chroma of 3 or 4 moist and dry. It is very gravelly loam, very moist and dry. It is clay loam, gravelly clay loam, or cobbly gravelly clay loam, or extremely gravelly loam. clay loam. Carney Series Caris Series The Carney series consists of moderately deep, The Caris series consists of moderately deep, well moderately well drained soils on alluvial fans and hillslopes. drained soils on hillslopes. These soils formed in colluvium These soils formed in alluvium and colluvium derived from derived from altered sedimentary and volcanic rock. Slopes igneous rock. Slopes are 1 to 35 percent. The mean annual are 50 to 80 percent. The mean annual precipitation is about precipitation is about 24 inches, and the mean annual 32 inches, and the mean annual temperature is about 50 temperature is about 53 degrees F. degrees F. Typical pedon of Carney clay, 1 to 5 percent slopes, Typical pedon of Caris gravelly loam, in an area of about 10 miles north of Medford; about 300 feet south and Caris-Offenbacher gravelly loams, 50 to 80 percent north 1,320 feet east of the northwest corner of sec. 5, T. 36 S., slopes, about 3 miles southeast of Ruch; about 380 feet R. 1 W. west and 500 feet south of the northeast corner of sec. 31, T. 38 S., R. 2 W. A1-0 to 1 1/2 inches; dark brown (10YR 3/3) clay, dark grayish brown (10YR 4/2) dry; strong fine granular Oi-1 inch to 0; needles and twigs. structure; very hard, very firm, very sticky and very A-0 to 7 inches; very dark grayish brown (10YR 3/2) gravelly plastic; many fine roots; many fine irregular pores; loam, light brownish gray (10YR 6/2) dry; strong neutral (pH 7.2); clear smooth boundary. medium and fine granular structure; soft, friable, slightly A2-1 1/2 to 6 inches; dark brown (10YR 3/3) clay, dark sticky and slightly plastic; many very fine and fine roots; grayish brown (10YR 4/2) dry; strong fine and medium many irregular pores; 30 percent gravel; neutral (pH subangular blocky structure; very hard, very firm, very 6.8); abrupt smooth boundary. sticky and very plastic; many fine roots; many fine BA-7 to 12 inches; dark yellowish brown (10YR 3/4) very irregular pores; neutral (pH 7.2); clear smooth gravelly clay loam, pale brown (10YR 6/3) dry; boundary. moderate very fine and fine subangular blocky AB-6 to 12 inches; dark brown (10YR 3/3) clay, dark structure; slightly hard, friable, slightly sticky and slightly grayish brown (10YR 4/2) dry; moderate coarse plastic; many very fine and fine roots; many prismatic structure parting to strong coarse and medium fine subangular blocky structure; hard, friable, slightly angular blocky; appears massive when wet; extremely sticky and slightly plastic; many roots; many very fine hard, extremely firm, very sticky and very plastic; few and fine tubular pores; common wormholes and fine roots; common very fine tubular pores; neutral (pH wormcasts; slightly acid (pH 6.4); clear wavy boundary. 7.0); clear smooth boundary. Bw1-30 to 42 inches; very dark grayish brown (10YR 3/2) Bw-12 to 35 inches; dark brown (10YR 3/3) clay, dark sandy loam, dark grayish brown (10YR 4/2) dry; weak grayish brown (10YR 4/2) dry; massive with vertical medium prismatic structure parting to weak medium cracks 6 to 18 inches apart; extremely hard, very firm, subangular blocky; very hard, friable, slightly sticky and very sticky and very plastic; intersecting slickensides; slightly plastic; common fine roots; many very fine and few fine roots; common fine tubular pores; neutral (pH fine tubular pores; common wormholes and wormcasts; 7.0); abrupt smooth boundary. krotovina of material from the A horizon at a depth of 2Crk-35 inches; weathered sandstone that is calcareous in 34 inches; neutral (pH 6.6); gradual wavy boundary. the fractures. Bw2-42 to 49 inches; dark brown (10YR 3/3) sandy loam, brown (10YR 5/3) dry; common fine distinct yellowish The depth to bedrock is 20 to 40 inches. The red mottles; weak medium prismatic structure parting to particle-size control section contains 50 to 60 percent clay. weak coarse subangular blocky; very hard, friable, In most years the soils have cracks that are open to the sticky and plastic; few fine roots; many fine tubular surface or to the base of the plow layer. The cracks are at pores; neutral (pH 6.6); clear wavy boundary. least 1 centimeter wide at a depth of 20 inches. The soils C1-49 to 59 inches; dark brown (10YR 3/3) gravelly sandy have intersecting slickensides. loam, brown (10YR 5/3) dry; common fine distinct The A horizon has value of 2 or 3 moist, 3 or 4 dry, and yellowish red mottles; massive; very hard, friable, sticky chroma of 1.5 to 3 moist and dry. It is clay or cobbly clay. and plastic; few fine roots; many fine tubular pores; 25 The AB and Bw horizons have hue of 7.5YR and 10YR; percent angular fragments of quartz 2 to 4 millimeters value of 2 to 4 moist, 3 or 4 dry; and chroma of 2 or 3 in diameter; neutral (pH 6.6); abrupt wavy boundary. moist, 1 to 4 dry. In some pedons the Bw horizon is 2C2-59 to 67 inches; dark brown (10YR 3/3) gravelly loamy calcareous. sand, brown (10YR 4/3) dry; massive; loose, nonsticky and nonplastic; few roots; many tubular pores; 30 Central Point Series percent angular and rounded gravel; neutral (pH 6.7).

The Central Point series consists of very deep, well The depth to bedrock is 60 inches or more. The drained soils on stream terraces. These soils formed in particle-size control section contains 12 to 18 percent alluvium. Slopes are 0 to 3 percent. The mean annual clay. The mollic epipedon is 20 to 50 inches thick. precipitation is about 24 inches, and the mean annual The A horizon has value of 2 or 3 moist, 4 or 5 dry, and temperature is about 53 degrees F. chroma of 1 to 3 moist and dry. The Bw horizon has value of Typical pedon of Central Point sandy loam, 0 to 3 4 or 5 dry and chroma of 2 or 3 moist and dry. The C and percent slopes, on the Southern Oregon Branch 2C horizons, if they occur, are gravelly sandy loam or Experiment Station, about 35 feet north and 90 feet west gravelly loamy sand and in some pedons are stratified. of the southeast corner of a plot south of an irrigation sump; about 1,240 feet north and 890 feet west of the Clawson Series southeast corner of sec. 21, T. 37 S., R. 2 W. The Clawson series consists of very deep, poorly Ap-0 to 6 inches; black (10YR 2/1) sandy loam, dark gray drained soils on alluvial fans. These soils formed in (10YR 4/1) dry; weak medium granular structure; hard, alluvium derived from granitic rock. Slopes are 2 to 5 friable, nonsticky and slightly plastic; many very fine percent. The mean annual precipitation is about 35 roots; slightly acid (pH 6.4); clear smooth boundary. inches, and the mean annual temperature is about 52 A1-6 to 17 inches; black (10YR 2/1) sandy loam, dark gray degrees F. (10YR 4/1) dry; massive (compaction pan); hard, friable, Typical pedon of Clawson sandy loam, 2 to 5 percent nonsticky and slightly plastic; many very fine roots; slopes, about 1.5 miles northwest of Wimer; about 500 common fine and very fine pores; few wormcasts; slightly acid (pH 6.2); clear smooth boundary. A2-17 to 30 inches; very dark brown (10YR 2/2) sandy loam, dark gray (10YR 4/1) dry; weak medium and feet east and 1,000 feet north of the southwest corner of sandy loam to a depth of 40 inches. Below this depth, it is sec. 3, T. 35 S., R. 4 W. stratified with lenses of loamy coarse sand or loam in some pedons. A1-0 to 5 inches; very dark grayish brown (2.5Y 3/2) sandy loam, light brownish gray (2.5Y 6/2) dry; strong fine and Coker Series medium granular structure; slightly hard, very friable, slightly sticky and nonplastic; common very fine and fine The Coker series consists of very deep, somewhat roots; many irregular pores; 5 percent gravel; poorly drained soils on alluvial fans. These soils formed in moderately acid (pH 5.6); clear wavy boundary. clayey alluvium derived from igneous rock. Slopes are 0 to A2-5 to 10 inches; very dark grayish brown (2.5Y 3/2) sandy 12 percent. The mean annual precipitation is about 24 loam, light brownish gray (2.5Y 6/2) dry; moderate very inches, and the mean annual temperature is about 53 fine and fine subangular blocky structure; slightly hard, degrees F. friable, slightly sticky and nonplastic; few very fine roots; Typical pedon of Coker clay, 0 to 3 percent slopes, many very fine tubular pores; moderately acid (pH 5.6); about 1.5 miles west of Agate Reservoir; about 1,390 feet abrupt smooth boundary. south and 2,050 feet east of the northwest corner of sec. Bw-10 to 20 inches; dark grayish brown (2.5Y 4/2) sandy 27, T. 36 S., R. 1 W. loam, light brownish gray (2.5Y 6/2) dry; weak medium subangular blocky structure; slightly hard, friable, Ap-0 to 4 inches; very dark gray (10YR 3/1) clay, dark gray slightly sticky and nonplastic; few very fine roots; many (10YR 4/1) dry; strong fine and very fine granular very fine tubular pores; 5 percent gravel; slightly acid structure; extremely hard, extremely firm, very sticky (pH 6.1); gradual wavy boundary. and very plastic; many fine and very fine roots; many BC-20 to 45 inches; dark grayish brown (2.5Y 4/2) and irregular pores; neutral (pH 7.0); abrupt smooth grayish brown (2.5Y 5/2) sandy loam, light yellowish boundary. brown (2.5Y 6/4) dry; many large distinct and prominent A1-4 to 10 inches; very dark gray (10YR 3/1) clay, dark gray dark brown (7.5YR 3/4, 4/4) and strong brown (7.5YR (10YR 4/1) dry; weak medium and coarse angular 4/6) mottles; weak medium and coarse subangular blocky structure; extremely hard, extremely firm, very blocky structure; hard, friable, slightly sticky and slightly sticky and very plastic; few pressure faces; many very plastic; few very fine roots; common very fine tubular fine and fine roots; common very fine tubular pores; pores; 5 percent gravel; slightly acid (pH 6.4); gradual neutral (pH 7.2); clear smooth boundary. wavy boundary. A2-10 to 20 inches; very dark gray (10YR 3/1) clay, dark C-45 to 60 inches; dark grayish brown (2.5Y 4/2) and gray (10YR 4/1) dry; moderate coarse and medium grayish brown (2.5Y 5/2) sandy loam, light yellowish prismatic structure; extremely hard, extremely firm, very brown (2.5Y 6/4) dry; many large distinct and prominent sticky and very plastic; common slickensides; common dark brown (7.5YR 3/4, 4/4) and strong brown (7.5YR fine and very fine roots; common very fine tubular 4/6) mottles; massive; hard, friable, slightly sticky and pores; neutral (pH 7.2); gradual smooth boundary. slightly plastic; few very fine roots; few very fine tubular Ak-20 to 33 inches; very dark gray (10YR 3/1) clay, dark pores; 5 percent gravel; slightly acid (pH 6.4). gray (10YR 4/1) dry; moderate coarse and medium prismatic structure; extremely hard, extremely firm, very The depth to bedrock is 60 inches or more. The sticky and very plastic; common slickensides; common particle-size control section contains 8 to 18 percent fine roots; common very fine tubular pores; slightly clay. effervescent; few fine segregated soft masses of lime; The A horizon has hue of 10YR or 2.5Y; value of 2 to 4 mildly alkaline (pH 7.8); clear wavy boundary. moist, 5 or 6 dry; and chroma of 2 or less moist and dry. The ABk-33 to 46 inches; dark grayish brown (10YR 4/2) clay, Bw horizon has hue of 10YR or 2.5Y; value of 4 or 5 moist, grayish brown (10YR 5/2) dry; common tongues of 6 or 7 dry; and chroma of 2 or less moist, 2 to 4 dry. It has material that is very dark gray (10YR 3/1) and dark gray distinct or prominent mottles. The C horizon has hue of (10YR 4/1) dry; weak coarse prismatic structure; 10YR or 2.5Y; value of 4 to 6 moist, 6 to 8 dry; and chroma extremely hard, extremely firm, very sticky and very of 2 to 4 moist and dry. It has faint to prominent mottles. It is plastic; many intersecting slickensides; common fine sandy loam or coarse roots; few very fine tubular pores; strongly effervescent; few fine segregated soft masses of lime; moderately alkaline (pH 8.0); gradual wavy boundary. Bk1-46 to 59 inches; dark grayish brown (10YR 4/2) clay, dark brown (7.5YR 4/4) dry; common medium distinct grayish brown (10YR 5/2) dry; massive; extremely hard, strong brown (7.5YR 5/6) mottles; strong medium extremely firm, very sticky and very plastic; many prismatic structure; very hard, very firm, very sticky and intersecting slickensides; common fine roots; few very very plastic; few fine roots; few very fine and fine fine tubular pores; strongly effervescent; common fine tubular pores; common distinct and faint clay films on segregated soft masses of lime; moderately alkaline (pH faces of peds; slightly acid (pH 6.4); abrupt smooth 8.4); gradual wavy boundary. boundary. Bk2-59 to 70 inches; dark grayish brown (10YR 4/2) clay, 2Bt2-31 to 40 inches; dark brown (7.5YR 4/4) clay, dark grayish brown (10YR 5/2) dry; massive, extremely hard, brown (7.5YR 4/4) dry; few medium distinct strong extremely firm, very sticky and very plastic; few fine brown (7.5YR 5/6) mottles; weak coarse prismatic roots; few very fine tubular pores; strongly effervescent; structure parting to weak coarse subangular blocky; common medium segregated soft masses of lime; very hard, very firm, very sticky and very plastic; few moderately alkaline (pH 8.4). fine roots; common very fine pores; few distinct clay films on faces of peds and in pores; 5 percent gravel; The depth to bedrock is 60 inches or more. The neutral (pH 6.6); clear wavy boundary. particle-size control section contains 60 to 70 percent clay. 2C1-40 to 58 inches; dark brown (7.5YR 4/4) clay loam, In most years the soils have cracks that are open to the yellowish red (5YR 4/8) dry; massive; hard, firm, sticky surface or to the base of a plow layer. These cracks are at and plastic; many very fine pores; 10 percent gravel; least 1 centimeter wide at a depth of 20 inches. The soils neutral (pH 6.8); abrupt smooth boundary. have intersecting slickensides. 2C2-58 to 65 inches; yellowish red (5YR 4/6) clay loam, The A horizon has hue of 10YR or 2.5Y; value of 2 or 3 strong brown (7.5YR 5/8) dry; massive; hard, firm, moist, 3 to 5 dry; and chroma of 1.5 or less moist and dry. sticky and plastic; neutral (pH 7.0). The ABk and Bk horizons have hue of 10YR or 2.5Y, value of 4 or 5 moist and dry, and chroma of 2 to 4 moist and dry. The depth to bedrock is 60 inches or more. The A horizon has hue of 10YR, 7.5YR, or 5YR; value of 3 moist, Coleman Series 4 or 5 dry; and chroma of 2 or 3 moist, 3 or 4 dry. The Bt horizon has hue of 7.5YR or 5YR; value of 4 moist, 4 or 5 The Coleman series consists of very deep, moderately dry; and chroma of 3 or 4 moist and dry. It is clay or well drained soils on stream terraces. These soils formed in gravelly clay and contains 45 to 55 percent clay and 0 to 35 alluvium derived from sedimentary rock. Slopes are 0 to 7 percent rock fragments. The 2C horizon has hue of 10YR, percent. The mean annual precipitation is about 22 inches, 7.5YR, or 5YR; value of 4 moist, 4 to 6 dry; and chroma of and the mean annual temperature is about 52 degrees F. 3 to 8 moist and dry. It is clay loam, gravelly clay loam, or Typical pedon of Coleman loam, 0 to 7 percent slopes, very gravelly clay loam and contains 5 to 60 percent rock about 1,100 feet south of Dark Hollow Road and 325 feet fragments. west of Colver Road; about 840 feet west and 540 feet south of the northeast corner of sec. 21, T. 38 S., R. 1 W. Colestine Series

Ap-0 to 8 inches; dark brown (10YR 3/3) loam, yellowish The Colestine series consists of moderately deep, well brown (10YR 5/4) dry; weak fine granular structure; drained soils on hillslopes. These soils formed in colluvium slightly hard, friable, slightly sticky and slightly plastic; derived from altered sedimentary and volcanic rock. Slopes many roots; many very fine irregular pores; moderately are 50 to 80 percent. The mean annual precipitation is about acid (pH 5.8); abrupt smooth boundary. 45 inches, and the mean annual temperature is about 49 BA-8 to 20 inches; dark brown (7.5YR 3/3) clay loam, dark degrees F. yellowish brown (10YR 4/4) dry; weak coarse prismatic Typical pedon of Colestine gravelly loam, in an area of structure parting to weak coarse to fine subangular Beekman -Colestine gravelly loams, 50 to 80 percent north blocky; slightly hard, friable, sticky and plastic; many slopes, about 5.5 miles northwest of Gold Hill; about 1,885 roots; common very fine tubular pores; slightly acid (pH feet west and 1,760 feet north of the southeast corner of 6.4); abrupt smooth boundary. sec. 18, T. 35 S., R. 3 W. 2Bt1-20 to 31 inches; dark brown (7.5YR 4/4) clay, Oi-1 inch to 0; needles, leaves, and twigs. A-0 to 5 inches; very dark grayish brown (10YR 3/2) gravelly loam, brown (10YR 4/3) dry; weak fine granular structure; soft, friable, slightly sticky and gray (10YR 3/1) dry; weak medium prismatic structure slightly plastic; many fine and medium roots; many fine parting to weak medium subangular blocky; very hard, irregular pores; 20 percent gravel; neutral (pH 6.6); very firm, very sticky and very plastic; many very fine clear smooth boundary. and fine roots; many fine irregular pores; slightly acid AB-5 to 9 inches; dark brown (10YR 3/3) gravelly loam, (pH 6.5); clear wavy boundary. brown (10YR 5/3) dry; weak fine subangular blocky Bw1-16 to 32 inches; very dark gray (N 3/0) clay, dark gray structure; slightly hard, friable, slightly sticky and slightly (N 4/0) dry; common fine distinct mottles; weak coarse plastic; many fine and medium roots; common very fine prismatic structure parting to moderate fine subangular tubular pores; 15 percent gravel; neutral (pH 6.6); blocky; very hard, very firm, very sticky and very plastic; gradual smooth boundary. common fine roots; many fine tubular pores; neutral (pH Bw1-9 to 19 inches; dark yellowish brown (10YR 4/4) 6.6); gradual wavy boundary. gravelly loam, yellowish brown (10YR 5/4) dry; Bw2-32 to 50 inches; very dark gray (N 3/0) clay, dark gray moderate medium subangular blocky structure; slightly (N 4/0) dry; common fine distinct mottles; weak coarse hard, friable, slightly sticky and slightly plastic; common prismatic structure parting to moderate fine subangular medium and few large roots; many very fine tubular blocky; very hard, very firm, very sticky and very plastic; pores; 25 percent gravel; slightly acid (pH 6.4); clear common fine roots; many fine tubular pores; neutral (pH smooth boundary. 6.8); clear wavy boundary. Bw2-19 to 34 inches; brown (7.5YR 4/4) gravelly loam, C-50 to 60 inches; dark grayish brown (2.5Y 4/2) silty clay, yellowish brown (10YR 5/4) dry; moderate medium grayish brown (2.5Y 5/2) dry; common fine distinct subangular blocky structure; slightly hard, friable, mottles; massive; very hard, firm, sticky and plastic; slightly sticky and slightly plastic; common medium and common fine roots; many fine and medium tubular few large roots; many fine and very fine tubular pores; pores; neutral (pH 7.2). 20 percent gravel and 10 percent cobbles; neutral (pH 6.6); clear smooth boundary. The soils are saturated to the surface for at least 1 month R-34 inches; highly fractured, metamorphosed bedrock. in most years. The depth to bedrock is 60 inches or more. In most years the soils have cracks that are open to the The depth to bedrock is 20 to 40 inches. The surface or to the base of a plow layer. These cracks are at particle-size control section contains 22 to 30 percent least 1 centimeter wide at a depth of 20 inches. The soils do clay and 15 to 35 percent rock fragments. not have intersecting slickensides. The particle-size control The A horizon has value of 3 or 4 moist, 4 to 6 dry, and section contains 50 to 60 percent clay. chroma of 2 to 4 moist, 3 or 4 dry. The Bw horizon has hue The A horizon has hue of 10YR or 2.5Y or is neutral in of 2.5Y, 10YR, or 7.5YR; value of 4 or 5 moist, 5 to 7 dry; hue. It has value of 2 or 3 moist, 3 to 5 dry, and chroma of and chroma of 3 to 6 moist and dry. It is gravelly loam or 0 or 1. The Bw and C horizons have hue of 2.5Y, 5Y, or gravelly clay loam. 10YR or are neutral in hue. They have value of 2 to 4 moist, 4 or 5 dry, and chroma of 0 to 2 moist and dry. They Cove Series are clay or silty clay. The Cove series consists of very deep, poorly drained soils on flood plains. These soils formed in clayey alluvium Coyata Series derived from igneous rock. Slopes are 0 to 3 percent. The The Coyata series consists of moderately deep, well mean annual precipitation is about 24 inches, and the mean drained soils on plateaus and hillslopes. These soils formed annual temperature is about 53 degrees F. in colluvium and residuum derived from igneous rock. Typical pedon of Cove clay, 0 to 3 percent slopes, about Slopes are 0 to 80 percent. The mean annual precipitation 0.5 mile north of Tou Velle State Park; about 125 feet west is about 45 inches, and the mean annual temperature is and 125 feet north of the southeast corner of sec. 11, T. 36 about 48 degrees F. S., R. 2 W. Typical pedon of Coyata gravelly loam, in an area of A-0 to 7 inches; black (10YR 2/1) clay, very dark gray Dumont-Coyata gravelly loams, 12 to 35 percent north (10YR 3/1) dry; moderate medium and fine granular slopes, about 3 miles west of Medco Pond; about 200 feet structure; very hard, very firm, very sticky and very north and 750 feet east of the southwest corner of sec. 32, plastic; many very fine roots; many fine irregular pores; T. 33 S., R. 3 E. slightly acid (pH 6.5); abrupt smooth boundary. AB-7 to 16 inches; black (10YR 2/1) clay, very dark Oi-1 1/2 inches to 0; needles, leaves and twigs. and fine granular structure; soft, very friable, nonsticky A-0 to 11 inches; dark reddish brown (5YR 3/2) gravelly and nonplastic; many very fine and fine and common loam, brown (7.5YR 4/2) dry; weak fine granular medium and coarse roots; common fine and very fine structure; soft, very friable, nonsticky and nonplastic; pores; 5 percent gravel and 5 percent cobbles; slightly many very fine and fine roots; many fine irregular pores; acid (pH 6.4); clear smooth boundary. 20 percent gravel and 10 percent cobbles; moderately Bw-5 to 22 inches; dark yellowish brown (10YR 4/4) sandy acid (pH 6.4); clear wavy boundary. loam, light yellowish brown (10YR 6/4) dry; weak very BA-11 to 21 inches; dark brown (7.5YR 3/4) very cobbly fine and fine subangular blocky structure; soft, very clay loam, dark brown (7.5YR 4/4) dry; weak fine friable, nonsticky and nonplastic; common very fine, subangular blocky structure; soft, very friable, slightly fine, medium, and coarse roots; common fine and very sticky and nonplastic; many very fine, fine, and medium fine pores; 5 percent gravel and 5 percent cobbles; and common coarse roots; many very fine irregular slightly acid (pH 6.4); gradual wavy boundary. pores; 20 percent gravel, 15 percent cobbles, and 10 C1-22 to 50 inches; strong brown (7.5YR 5/6) sandy loam, percent stones; moderately acid (pH 5.8); clear wavy pink (7.5YR 7/4) dry; massive; slightly hard, friable, boundary. nonsticky and nonplastic; common very fine, fine, Bw-21 to 31 inches; dark brown (7.5YR 4/4) extremely medium, and coarse roots; many very fine and fine cobbly clay loam, strong brown (7.5YR 4/6) dry; tubular pores; 5 percent gravel and 5 percent cobbles; moderate fine subangular blocky structure; slightly hard, moderately acid (pH 5.6); gradual wavy boundary. friable, slightly sticky and slightly plastic; many fine and C2-50 to 60 inches; brown (7.5YR 5/4) sandy loam, pink common very fine and medium roots; few fine tubular (7.5YR 7/4) dry; massive; slightly hard, friable, pores; 35 percent gravel, 20 percent cobbles, and 10 nonsticky and nonplastic; few very fine, fine, and percent stones; strongly acid (pH 5.2); abrupt wavy medium roots; many tubular pores; 5 percent gravel; boundary. moderately acid (pH 5.6). R-31 inches; fractured andesite. The depth to bedrock is 60 inches or more. The The depth to bedrock is 20 to 40 inches. The particle-size control section contains 60 or more percent particle-size control section contains 35 to 70 percent volcanic ash and pumice. It has a bulk density of 0.75 to rock fragments and 25 to 35 percent clay. The umbric 0.90 gram per cubic centimeter. epipedon is 10 to 20 inches thick. The A horizon has hue of 10YR or 7.5YR; value of 2 to 4 The A horizon has hue of 5YR or 7.5YR; value of 2 or 3 moist, 4 to 6 dry; and chroma of 2 to 4 moist and dry. The moist, 4 or 5 dry; and chroma of 2 or 3 moist and dry. It is Bw horizon has hue of 10YR or 7.5YR; value of 3 to 5 gravelly loam or very stony loam. The Bw horizon has hue moist, 5 to 7 dry; and chroma of 4 to 6 moist, 3 or 4 dry. It is of 5YR or 7.5YR; value of 3 or 4 moist, 4 to 6 dry; and sandy loam, fine sandy loam, or very fine sandy loam. The chroma of 3 to 6 moist and dry. It is very cobbly clay loam, C horizon has hue of 10YR, 7.5YR, or 2.5Y; value of 4 to 6 extremely cobbly clay loam, or very cobbly loam. moist, 6 to 8 dry; and chroma of 3 to 6 moist, 2 to 4 dry. It is sandy loam, fine sandy loam, or gravelly sandy loam and Crater Lake Series contains 0 to 25 percent rock fragments.

The Crater Lake series consists of very deep, well Darow Series drained soils on plateaus and hillslopes. These soils formed in volcanic ash and pumice. Slopes are 1 to 70 The Darow series consists of moderately deep, percent. The mean annual precipitation is about 45 inches, moderately well drained soils on hillslopes. These soils and the mean annual temperature is about 48 degrees F. formed in colluvium derived from sedimentary rock. Slopes Typical pedon of Crater Lake sandy loam, in an area of are 1 to 35 percent. The mean annual precipitation is about Crater Lake-Alcot complex, 1 to 12 percent slopes, about 1 24 inches, and the mean annual temperature is about 53 mile northwest of Prospect; about 400 feet west and 1,350 degrees F. feet south of the northeast corner of sec. 31, T. 32 S., R. 3 Typical pedon of Darow silty clay loam, 20 to 35 E. percent slopes, about 4 miles south of Medford; about 1,750 feet west and 850 feet south of the northeast corner Oi-3 inches to 0; needles and twigs. of sec. 13, T. 38 S., R. 2 W. A-0 to 5 inches; dark yellowish brown (10YR 3/4) sandy loam, brown (10YR 4/3) dry; weak very fine A1-0 to 5 inches; dark brown (10YR 3/3) silty clay loam, brown (10YR 5/3) dry; strong medium granular structure; hard, friable, slightly sticky and plastic; many fine roots; many irregular pores; neutral (pH 6.8); abrupt smooth boundary. A2-5 to 12 inches; dark brown (10YR 3/3) silty clay loam, brown (10YR 5/3) dry; moderate fine subangular blocky structure; hard, friable, sticky and plastic; common fine and few medium roots; many very fine tubular pores; neutral (pH 6.6); clear smooth boundary. BA-12 to 21 inches; dark brown (10YR 4/3) silty clay, yellowish brown (10YR 5/4) dry; weak coarse subangular blocky structure; very hard, firm, very sticky and plastic; few fine and medium roots; common very fine tubular pores; slightly acid (pH 6.4); clear smooth boundary. Bt-21 to 32 inches; dark yellowish brown (10YR 4/4) silty clay, yellowish brown (10YR 5/4) dry; weak coarse prismatic structure; very hard, very firm, very sticky and very plastic; common fine roots; common very fine tubular pores; few distinct clay films on faces of peds and in pores; slightly acid (pH 6.4); clear wavy boundary. Crt-32 inches; weathered siltstone; prominent dark brown (7.5YR 4/4) clay films in fractures.

The depth to bedrock is 20 to 40 inches (fig. 16). The particle-size control section contains 45 to 60 percent clay. In most years the soils have cracks that are open to the surface or to the base of a plow layer. These cracks are at least 1 centimeter wide at a depth of 20 inches. The soils do not have intersecting slickensides. The A horizon has hue of 10YR or 7.5YR and chroma of 2 or 3 moist, 3 or 4 dry. The Bt horizon has hue of 10YR, 7.5YR, or 2.5Y; value of 4 or 5 moist, 5 or 6 dry; and Figure 16.-Profile of a Darow silty clay loam. Siltstone is at a depth of about 2 feet. chroma of 3 or 4 moist and dry. It is silty clay or clay.

Debenger Series friable, slightly sticky and slightly plastic; many very The Debenger series consists of moderately deep, well fine and fine roots; many irregular pores; slightly acid drained soils on knolls and ridges. These soils formed in (pH 6.2); clear smooth boundary. colluvium derived from sandstone. Slopes are 1 to 40 A2-5 to 9 inches; reddish brown (5YR 4/4) loam, reddish percent. The mean annual precipitation is about 24 inches, brown (5YR 5/4) dry; moderate thick platy and and the mean annual temperature is about 53 degrees F. moderate medium subangular blocky structure; friable, Typical pedon of Debenger loam, in an area of slightly sticky and slightly plastic; many fine roots; Debenger-Brader loams, 1 to 15 percent slopes, about 6 many fine irregular pores; slightly acid (pH 6.2); clear miles north of Tou Velle State Park; about 2,400 feet west smooth boundary. and 1,600 feet south of the northeast corner of sec. 14, T. Bw1-9 to 18 inches; reddish brown (5YR 4/4) clay loam, 35 S., R. 2 W. yellowish red (5YR 4/6) dry; moderate medium subangular blocky structure; firm, sticky and plastic; few A1-0 to 5 inches; dark brown (7.5YR 3/4) loam, brown fine roots; common very fine tubular pores; moderately (7.5YR 5/4) dry; moderate medium platy structure; acid (pH 6.0); clear smooth boundary. Bw2-18 to 27 inches; yellowish red (5YR 4/6) clay loam, yellowish red (5YR 4/6) dry; moderate medium The depth to bedrock is 20 to 40 inches. The subangular blocky structure; hard, firm, sticky and particle-size control section contains 35 to 75 percent plastic; few fine roots; common very fine tubular pores; rock fragments and 20 to 35 percent clay. The umbric moderately acid (pH 5.9); abrupt smooth boundary. epipedon is 20 to 40 inches thick. 2Cr-27 inches; partially decomposed sandstone. The A horizon has hue of 5YR or 7.5YR; value of 2 or 3 moist, 3 to 5 dry; and chroma of 2 or 3 moist and dry. The The depth to bedrock is 20 to 40 inches. The Bw horizon has hue of 5YR or 7.5YR; value of 3 or 4 moist, particle-size control section contains 20 to 35 percent 4 or 5 dry; and chroma of 2 or 3 moist, 3 or 4 dry. It is very clay. cobbly loam, extremely gravelly loam, extremely gravelly The A horizon has hue of 5YR, 7.5YR, or 10YR; value of clay loam, or very gravelly clay loam.. 3 or 4 moist, 5 or 6 dry; and chroma of 2 to 4 moist and dry. The Bw horizon has hue of 5YR, 7.5YR, or 10YR; value of 4 Dubakella Series to 6 dry; and chroma of 3 to 6 moist and dry. It is clay loam or loam. The Dubakella series consists of moderately deep, well drained soils on hillslopes. These soils formed in colluvium Donegan Series derived from serpentinitic rock. Slopes are 12 to 70 percent. The mean annual precipitation is about 50 inches, The Donegan series consists of moderately deep, well and the mean annual temperature is about 49 degrees F. drained soils on plateaus and hillslopes. These soils formed Typical pedon of Dubakella very stony clay loam, rocky, in colluvium derived from igneous rock and volcanic ash. 35 to 70 percent slopes, about 5.5 miles northeast of Wimer; Slopes are 3 to 65 percent. The mean annual precipitation about 250 feet south and 1,500 feet west of the northeast is about 45 inches, and the mean annual temperature is corner of sec. 18, T. 34 S., R. 2 W. about 43 degrees F. Typical pedon of Donegan gravelly loam, in an area of A1-0 to 3 inches; dark reddish brown (5YR 3/4) very stony Donegan-Killet gravelly loams, 12 to 35 percent south clay loam, reddish brown (5YR 4/4) dry; moderate very slopes; about 200 feet north and 600 feet east of the fine and fine granular structure; soft, friable, slightly southwest corner of sec. 35, T. 33 S., R. 2 E. sticky and plastic; many very fine and fine roots; many very fine and fine irregular pores; stones covering 10 Oi-3 inches to 0; leaves, needles, and twigs. percent of the surface; slightly acid (pH 6.4); abrupt A-0 to 10 inches; dark brown (7.5YR 3/2) gravelly loam, smooth boundary. brown (7.5YR 4/2) dry; strong fine and medium A2-3 to 11 inches; dark reddish brown (2.5YR 3/4) very granular structure; soft, very friable, nonsticky and stony clay loam, reddish brown (5YR 4/4) dry; weak nonplastic; common very fine and fine roots; many very very fine subangular blocky structure; slightly hard, fine irregular pores; 25 percent gravel and 5 percent friable, sticky and plastic; common fine and medium cobbles; slightly acid (pH 6.4); abrupt smooth roots; many very fine and fine pores; 15 percent gravel, boundary. 15 percent cobbles, and 15 percent stones; slightly acid BA-10 to 22 inches; dark brown (7.5YR 3/2) gravelly loam, (pH 6.4); clear wavy boundary. brown (7.5YR 4/2) dry; moderate very fine and fine Bt1-11 to 19 inches; dark reddish brown (2.5YR 3/4) very subangular blocky structure; slightly hard, friable, cobbly clay, reddish brown (2.5YR 4/4) dry; weak very slightly sticky and slightly plastic; common very fine, fine and fine subangular blocky structure; hard, friable, fine, medium, and coarse roots; common very fine and sticky and plastic; common coarse and medium roots; fine tubular pores; 25 percent gravel and 9 percent many very fine and fine pores; common distinct clay cobbles; slightly acid (pH 6.4); clear wavy boundary. films on faces of peds and in pores; 15 percent gravel Bw-22 to 32 inches; dark brown (7.5YR 3/2) extremely and 35 percent cobbles; slightly acid (pH 6.4); clear gravelly loam, brown (7.5YR 4/2) dry; moderate very wavy boundary. fine and fine subangular blocky structure; hard, friable, Bt2-19 to 31 inches; dark reddish brown (5YR 3/4) very slightly sticky and slightly plastic; common very fine, cobbly clay, dark reddish brown (2.5YR 3/4) dry; weak fine, medium, and coarse roots; common very fine and fine and medium subangular blocky structure; hard, fine tubular pores; 45 percent gravel and 20 percent firm, sticky and very plastic; few very fine, fine, and cobbles; slightly acid (pH 6.2); abrupt irregular medium roots; many very fine and fine pores; many boundary. distinct clay films on faces of peds and in pores; 15 Cr-32 inches; weathered basalt. percent gravel and 40 percent cobbles; slightly acid (pH 6.4); abrupt common faint clay films on faces of peds; strongly acid irregular boundary. R-31 inches; fractured (pH 5.4); clear smooth boundary. serpentinite. Bt2-26 to 37 inches; dark reddish brown (5YR 3/4) clay, brown (7.5YR 4/4) dry; moderate medium subangular The depth to bedrock is 20 to 40 inches. The blocky structure; hard, firm, sticky and plastic; few fine particle-size control section contains 35 to 60 percent roots; common fine tubular pores; common distinct clay rock fragments and 35 to 50 percent clay. films on faces of peds; strongly acid (pH 5.2); clear The A horizon has hue of 7.5YR, 5YR, or 2.5YR; value smooth boundary. of 3 or 4 moist, 3 to 5 dry; and chroma of 2 to 4 moist and Bt3-37 to 68 inches; dark reddish brown (5YR 3/4) clay, dry. The Bt horizon has hue of 7.5YR, 5YR, or 2.5YR; brown (7.5YR 4/4) dry; few fine black stains; moderate value of 3 or 4 moist, 3 to 5 dry; and chroma of 3 or 4 moist medium and coarse subangular blocky structure; hard, and dry. It is very gravelly clay loam, very gravelly clay, or firm, sticky and plastic; few fine roots; many fine tubular very cobbly clay. pores; common distinct clay films on faces of peds; strongly acid (pH 5.2). Dumont Series The depth to bedrock is 60 inches or more. The The Dumont series consists of very deep, well drained particle-size control section contains 40 to 50 percent soils on plateaus and hillslopes. These soils formed in clay. colluvium and residuum derived from igneous rock and The A horizon has hue of 5YR or 7.5YR; value of 2 or 3 altered sedimentary and volcanic rock. Slopes are 1 to 60 moist, 3 to 5 dry; and chroma of 2 to 4 moist and dry. It is percent. The mean annual precipitation is about 45 inches, gravelly loam or gravelly clay loam. The Bt horizon has hue and the mean annual temperature is about 48 degrees F. of 5YR or 7.5YR; value of 3 or 4 moist, 4 or 5 dry; and Typical pedon of Dumont-gravelly loam, in an area of chroma of 3 or 4 moist, 3 to 6 dry. It is clay or silty clay. Dumont-Coyata gravelly loams, 12 to 35 percent north slopes, about 2 miles west of Medco Pond; about 2,400 feet Evans Series north and 2,600 feet west of the southeast corner of sec. 28, T. 33 S., R. 3 E. The Evans series consists of very deep, well drained soils on flood plains. These soils formed in alluvium. Slopes Oi-1 inch to 0; needles, leaves, and twigs. are 0 to 3 percent. The mean annual precipitation is about A1-0 to 6 inches; dark reddish brown (5YR 3/2) gravelly 30 inches, and the mean annual temperature is about 52 loam, dark brown (7.5YR 4/4) dry; moderate fine degrees. F. granular structure; soft, friable, nonsticky and Typical pedon of Evans loam, 0 to 3 percent slopes, nonplastic; many very fine and fine irregular pores; 15 about 2 miles south of Shady Cove; about 1,400 feet west percent gravel; moderately acid (pH 6.0); abrupt smooth and 300 feet north of the southeast corner of sec. 29, T. 34 boundary. S., R. 1 W. A2-6 to 9 inches; dark reddish brown (5YR 3/3) gravelly loam, dark brown (7.5YR 3/4) dry; weak fine subangular A1-0 to 8 inches; very dark brown (10YR 2/2) loam, dark blocky structure parting to moderate fine granular; soft, grayish brown (10YR 4/2) dry; moderate very fine and friable, nonsticky and nonplastic; many very fine and fine subangular blocky structure parting to moderate fine and common medium and coarse roots; many very very fine granular; soft, friable, slightly sticky and fine and fine irregular pores; 15 percent gravel; slightly plastic; many very fine and fine roots; many moderately acid (pH 5.8); clear smooth boundary. very fine and fine irregular and tubular pores; 10 AB-9 to 18 inches; dark reddish brown (5YR 3/4) clay loam, percent gravel; moderately acid (pH 6.0); brown (7.5YR 4/4) dry; weak fine subangular blocky abrupt smooth boundary., structure; slightly hard, friable, slightly sticky and slightly A2-8 to 26 inches; very dark brown (10YR 2/2) loam, plastic; many very fine and fine and common medium dark grayish brown (10YR 4/2) dry; moderate very and coarse roots; few fine tubular pores; 5 percent fine and fine subangular blocky structure; soft, gravel; strongly acid (pH 5.4); clear smooth boundary. friable, slightly sticky and slightly plastic; many very Bt1-18 to 26 inches; dark reddish brown (5YR 3/4) clay, fine and fine roots; many very fine and fine irregular brown (7.5YR 4/4) dry; moderate medium subangular and tubular pores; 10 percent gravel; slightly acid blocky structure; hard, firm, sticky and plastic; few fine (pH 6.2); clear smooth boundary. roots; common fine tubular pores; A3-26 to 38 inches; very dark brown (10YR 2/2) loam, brown (10YR 5/3) dry; moderate fine and medium subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; common very fine medium, and coarse roots; many fine tubular pores; 25 and fine roots; many very fine and fine irregular and percent gravel, 25 percent cobbles, and 15 percent tubular pores; 5 percent gravel; slightly acid (pH 6.3); stones; slightly acid (pH 6.2); gradual wavy boundary. clear smooth boundary. C-27 to 35 inches; brown (7.5YR 4/4) extremely cobbly C-38 to 60 inches; dark brown (7.5YR 3/2) loam, yellowish loam, brown (7.5YR 5/4) dry; massive; soft, very brown (10YR 5/4) dry; massive; slightly hard, friable, friable, nonsticky and nonplastic; few medium and slightly sticky and slightly plastic; common very fine, coarse roots; many irregular pores; 20 percent gravel, fine, and medium roots; many very fine and fine 35 percent cobbles, and 10 percent stones; moderately irregular and tubular pores; 2 percent gravel; slightly acid (pH 5.8); abrupt wavy boundary. acid (pH 6.4). 2Cr-35 inches; partially weathered andesitic bedrock.

The depth to bedrock is 60 inches or more. The The depth to bedrock is 20 to 40 inches. The particle-size control section contains 10 to 18 percent clay particle-size control section contains 45 to 80 percent and 15 or more percent fine sand or coarser sand. The rock fragments and 15 to 25 percent clay. mollic epipedon is 20 to 40 inches thick. The soils are The A and AB horizons have hue of 5YR, 7.5YR, or characterized by an irregular decrease in content of organic 10YR; value of 3 to 5 moist, 4 or 5 dry; and chroma of 2 to 4 matter to a depth of 50 inches. moist and dry. The Bw and C horizons have hue of 5YR or The A horizon has value of 2 or 3 moist, 4 or 5 dry, and 7.5YR; value of 3 or 4 moist, 4 or 5 dry; and chroma of 3 or chroma of 2 or 3 moist, 2 to 4 dry. The C horizon has hue of 4 moist and dry. They are extremely cobbly or very cobbly 10YR or 7.5YR; value of 3 or 4 moist, 4 to 6 dry; and loam. chroma of 2 or 3 moist, 2 to 4 dry. It is loam, silt loam, or very fine sandy loam. Foehlin Series

Farva Series The Foehlin series consists of very deep, well drained soils on stream terraces. These soils formed in alluvium The Farva series consists of moderately deep, well derived from altered sedimentary and volcanic rock. Slopes drained soils on plateaus and hillslopes. These soils are 0 to 3 percent. The mean annual precipitation is about formed in colluvium derived from igneous rock and 30 inches, and the mean annual temperature is about 53 volcanic ash. Slopes are 3 to 70 percent. The mean degrees F. annual precipitation is about 43 inches, and the mean Typical pedon of Foehlin gravelly loam, 0 to 3 percent annual temperature is about 43 degrees F. slopes; about 660 feet west and 1,300 feet south of the Typical pedon of Farva very cobbly loam, 12 to 35 northeast corner of sec. 25, T. 35 S., R. 3 W. percent south slopes, about 0.3 mile north of Hyatt Lake; about 1,850 feet south and 700 feet east of the northwest Ap-0 to 4 inches; very dark grayish brown (10YR 3/2) corner of sec. 11, T. 39 S., R. 3 E. gravelly loam, grayish brown (10YR 5/2) dry; strong fine subangular blocky structure parting to strong fine and Oi-1/2 inch to 0; needles, leaves, and twigs. very fine granular; slightly hard, friable, slightly sticky A-0 to 5 inches; dark brown (7.5YR 3/2) very cobbly loam, and slightly plastic; many fine and very fine roots; brown (10YR 4/3) dry; moderate fine granular structure; common fine and very fine irregular pores; 15 percent soft, very friable, nonsticky and nonplastic; common gravel; moderately acid (pH 5.6); abrupt smooth medium and fine roots; many irregular pores; 20 boundary. percent gravel and 25 percent cobbles; slightly acid (pH A1-4 to 11 inches; very dark grayish brown (10YR 3/2) clay 6.4); clear wavy boundary. loam, grayish brown (10YR 5/2) dry; moderate coarse, AB-5 to 12 inches; dark brown (7.5YR 3/4) very cobbly medium, and fine subangular blocky structure; hard, loam, brown (7.5YR 4/4) dry; weak fine granular firm, sticky and plastic; common fine and very fine roots; structure; soft, very friable, nonsticky and nonplastic; common very fine tubular and irregular pores; 5 percent common medium and fine roots; many irregular pores; gravel; moderately acid (pH 5.6); abrupt smooth 20 percent gravel, 25 percent cobbles, and 10 percent boundary. stones; slightly acid (pH 6.3); gradual wavy boundary. A2-11 to 19 inches; very dark grayish brown (10YR 3/2) clay Bw-12 to 27 inches; brown (7.5YR 4/4) extremely cobbly loam, grayish brown (10YR 5/2) dry; moderate fine and loam, brown (7.5YR 5/4) dry; weak medium and fine very fine subangular blocky structure; hard, friable, subangular blocky structure; slightly hard, very friable, sticky and plastic; common nonsticky and slightly plastic; few fine, fine and very fine roots; many very fine and fine A1-0 to 3 inches; dark reddish brown (5YR 3/2) gravelly irregular and tubular pores; 5 percent gravel; loam, dark brown (7.5YR 4/3) dry; strong very fine moderately acid (pH 5.6); clear smooth boundary. granular structure; soft, very friable, nonsticky and Bt1-19 to 34 inches; dark brown (10YR 3/3) clay loam, nonplastic; many very fine roots; many fine and brown (10YR 5/3) dry; moderate medium, fine, and very medium irregular pores; 15 percent gravel; fine subangular blocky structure; hard, friable, sticky moderately acid (pH 6.0); abrupt smooth boundary. and plastic; common very fine, fine, and medium roots; A2-3 to 9 inches; dark reddish brown (5YR 3/4) gravelly many very fine and fine tubular and irregular pores; loam, brown (7.5YR 5/4) dry; moderate fine granular common faint and distinct clay films on faces of peds and moderate very fine subangular blocky structure; and many distinct clay films in pores; 5 percent gravel; soft, friable, slightly sticky and slightly plastic; many moderately acid (pH 5.7); clear smooth boundary. very fine and common fine roots; common very fine Bt2-34 to 42 inches; brown (10YR 4/3) clay loam, brown tubular and many very fine, fine, and medium irregular (10YR 5/3) dry; weak medium, fine, and very fine pores; 15 percent gravel; moderately acid (pH 5.8); subangular blocky structure; hard, friable, sticky and clear wavy boundary. plastic; few very fine, fine, and medium roots; many Bt1-9 to 18 inches; dark reddish brown (5YR 3/4) clay very fine and fine tubular pores; common faint clay films loam, dark brown (7.5YR 4/4) dry; moderate very fine on faces of peds and common faint and distinct clay subangular blocky structure; hard, firm, sticky and films in pores; 5 percent gravel; moderately acid (pH plastic; few fine and medium roots; common very fine 5.7); gradual smooth boundary. tubular and common very fine and fine irregular pores; Bt3-42 to 60 inches; dark yellowish brown (10YR 4/4) clay few distinct clay films on faces of peds; 5 percent loam, yellowish brown (10YR 5/4) dry; common fine gravel; moderately acid (pH 5.8); clear smooth distinct light brownish gray (2.5Y 6/2) mottles below a boundary. depth of 55 inches; massive; slightly hard, friable, sticky Bt2-18 to 28 inches; dark reddish brown (5YR 3/4) clay, and plastic; few very fine, fine, and medium roots; many dark brown (7.5YR 4/4) dry; moderate medium and fine very fine and fine tubular pores; common faint and subangular blocky structure; hard, firm, very sticky and distinct clay films in pores; 5 percent gravel; moderately very plastic; few fine and medium roots; common very acid (pH 5.8). fine tubular pores; common distinct clay films on faces of peds; 5 percent gravel; moderately acid (pH 5.6); The depth to bedrock is 60 inches or more. The gradual smooth boundary. particle-size control section contains 27 to 35 percent Bt3-28 to 45 inches; dark brown (7.5YR 3/4) clay, dark clay and 5 to 30 percent rock fragments. The mollic brown (7.5YR 4/4) dry; moderate medium angular epipedon is 10 to 20 inches thick. blocky structure; hard, very firm, very sticky and very The A horizon has hue of 10YR or 7.5YR; value of 2 or 3 plastic; few fine and medium roots; common very fine moist, 4 or 5 dry; and chroma of 2 or 3 moist and dry. The tubular pores; many distinct clay films on faces of peds; Bt horizon has hue of 10YR or 7.5YR; value of 3 or 4 moist, 5 percent gravel; strongly acid (pH 5.4); gradual smooth 5 or 6 dry; and chroma of 3 or 4 moist and dry. It is gravelly boundary. clay loam or clay loam. Bt4-45 to 60 inches; dark brown (7.5YR 3/4) clay loam, strong brown (7.5YR 4/6) dry; weak medium and Freezener Series coarse subangular blocky structure; hard, very firm, very sticky and very plastic; few fine and medium The Freezener series consists of very deep, well drained roots; common very fine tubular pores; many distinct soils on hillslopes and plateaus. These soils formed in and prominent clay films on faces of peds; 5 percent colluvium and residuum derived from igneous rock. Slopes gravel; strongly acid (pH 5.4). are 1 to 60 percent. The mean annual precipitation is about 40 inches, and the mean annual temperature is about 49 The depth to bedrock is 60 inches or more. The degrees F. particle-size control section contains 35 to 50 percent Typical pedon of Freezener gravelly loam, in an area of clay. Freezener-Geppert complex, 12 to 35 percent south slopes, The A horizon has hue of 5YR or 7.5YR; value of 3 about 7 miles northeast of Butte Falls; about 300 feet north or 4 moist, 4 or 5 dry; and chroma of 2 to 4 moist and and 400 feet east of the southwest corner of sec. 16, T. 34 dry. The Bt horizon has hue of 2.5YR, 5YR, or 7.5YR; S., R. 3 E. value of 3 or 4 moist, 4 to 6 dry; and chroma of 4 to 6 moist and dry. It is clay, silty clay, or clay loam. Oi-1 1/2 inches to 0; needles, leaves, and twigs. Geppert Series 3 to 6 moist and dry. It is very cobbly clay loam, extremely cobbly clay loam, or extremely cobbly loam. The Geppert series consists of moderately deep, well drained soils on plateaus and hillslopes. These soils formed Goolaway Series in colluvium derived from igneous rock. Slopes are 1 to 70 percent. The mean annual precipitation is about 40 inches, The Goolaway series consists of moderately deep, well and the mean annual temperature is about 49 degrees F. drained soils on hillslopes. These soils formed in colluvium Typical pedon of Geppert very cobbly loam, 35 to 70 derived from altered volcanic rock. Slopes are 12 to 50 percent north slopes, about 2 miles north of Butte Falls; percent. The mean annual precipitation is about 45 inches, about 1,800 feet north and 1,450 feet west of the southeast and the mean annual temperature is about 49 degrees F. corner of sec. 35, T. 34 S., R. 2 E. Typical pedon of Goolaway silt loam, 35 to 50 percent north slopes, about 2 miles east of Battle Mountain; about Oi-1/2 inch to 0; needles, leaves, and twigs. 2,340 feet east and 1,510 feet south of the northwest corner A1-0 to 4 inches; dark reddish brown (5YR 3/3) very cobbly of sec. 5, T. 34 S., R. 3 W. loam, dark brown (7.5YR 3/4) dry; weak fine subangular blocky structure parting to moderate medium granular; Oi-2 inches to 0; leaves, needles, and twigs. soft, friable, slightly sticky and slightly plastic; many fine A-0 to 3 inches; very dark grayish brown (2.5YR 3/2) silt and very fine and few medium roots; many fine irregular loam, grayish brown (2.5YR 5/2) dry; weak very fine pores; 15 percent gravel and 25 percent cobbles; granular structure; soft, very friable, slightly sticky and neutral (pH 6.6); clear smooth boundary. slightly plastic; many very fine and fine roots; many A2-4 to 13 inches; dark reddish brown (5YR 3/4) very very fine irregular pores; moderately acid (pH 5.7); cobbly loam, dark brown (7.5YR 3/4) dry; weak medium abrupt wavy boundary. subangular blocky structure parting to moderate fine BA-3 to 11 inches; dark grayish brown (2.5YR 4/2) silt loam, granular; slightly hard, friable, slightly sticky and slightly light brownish gray (2.5YR 6/2) dry; moderate fine plastic; many fine and very fine and few medium roots; subangular blocky structure; slightly hard, friable, many fine irregular pores; 15 percent gravel and 30 slightly sticky and slightly plastic; many very fine and percent cobbles; slightly acid (pH 6.4); clear wavy fine and common medium and coarse roots; few very boundary. fine tubular pores; 5 percent soft gravel; moderately Bw1-13 to 24 inches; dark reddish brown (5YR 3/4) acid (pH 5.7); clear irregular boundary. extremely cobbly clay loam, dark reddish gray (5YR Bt1-11 to 25 inches; olive gray (5Y 4/2) silt loam, light olive 4/2) dry; moderate medium subangular blocky gray (5Y 6/2) dry; moderate medium and coarse structure; hard, friable, sticky and plastic; common fine subangular blocky structure; hard, friable, slightly sticky and medium and few coarse roots; many very fine and slightly plastic; common very fine and fine and few tubular pores; 15 percent gravel and 50 percent medium and coarse roots; common very fine and fine cobbles; slightly acid (pH 6.4); clear wavy boundary. tubular pores; few faint clay films on faces of peds and Bw2-24 to 30 inches; dark reddish brown (5YR 3/4) in pores; 5 percent soft gravel; moderately acid (pH extremely cobbly clay loam, dark reddish gray (5YR 5.7); clear irregular boundary. 4/2) dry; moderate medium subangular blocky Bt2-25 to 29 inches; olive (5Y 4/3) silt loam, pale olive (5Y structure; hard, firm, sticky and plastic; few fine roots; 6/3) dry; moderate medium and coarse subangular common very fine tubular pores; common black stains blocky structure; hard, firm, slightly sticky and slightly on rock fragments; 20 percent gravel and 60 percent plastic; few very fine roots; common very fine tubular cobbles; moderately, acid (pH 6.0); clear wavy pores; few distinct clay films on faces of peds and in boundary. pores; 10 percent soft gravel; moderately acid (pH 5.8); Cr-30 inches; partially weathered andesite. clear wavy boundary. Cr-29 inches; highly decomposed schist. The depth to bedrock is 20 to 40 inches. The particle-size control section contains 50 to 80 percent The depth to bedrock is 20 to 40 inches. The rock fragments and 20 to 35 percent clay. particle-size control section contains 18 to 27 percent The A horizon has hue of 5YR or 7.5YR; value of 2 to 4 clay and less than 15 percent fine sand or coarser sand. moist, 3 to 5 dry; and chroma of 3 or 4 moist, 2 to 4 dry. The A horizon has hue of 10YR, 2.5Y, or 5Y; value The Bw horizon has hue of 2.5YR, 5YR, or 7.5YR; value of 3 or 4 moist, 4 or 5 dry; and chroma of of 3 or 4 moist, 4 to 6 dry; and chroma of 2 or 3 moist and rock fragments and 27 to 35 percent clay. dry. The Bw horizon has hue of 2.5Y or 5Y; value of 4 or 5 The A horizon has hue of 10YR or 7.5YR; value of 2 to 4 moist, 5 or 6 dry; and chroma of 2 or 3 moist, 2 to 4 dry. moist, 4 to 6 dry; and chroma of 1 to 4 moist, 2 to 4 dry. It is gravelly or cobbly loam. The Bw horizon has hue of 7.5YR, Gravecreek Series 10YR, or 2.5Y; value of 3 to 5 moist, 5 to 7 dry; and chroma of 3 or 4 moist and dry. It is very cobbly or very gravelly clay The Gravecreek series consists of moderately deep, loam. well drained soils on ridges and hillslopes. These soils formed in colluvium derived from serpentinitic rock. Slopes Gregory Series are 12 to 80 percent. The mean annual precipitation is about 50 inches, and the mean annual temperature is The Gregory series consists of deep, poorly drained soils about 48 degrees F. on stream terraces. These soils formed in alluvium derived Typical pedon of Gravecreek gravelly loam, 35 to 55 from altered sedimentary and volcanic rock. Slopes are 0 to percent north slopes; about 1,700 feet west and 2,300 feet 3 percent. The mean annual precipitation is about 24 north of the southeast corner of sec. 33, T. 33 S., R. 4 W. inches, and the mean annual temperature is about 53 degrees F. Oi-1 inch to 0; needles, leaves, and twigs. Typical pedon of Gregory silty clay loam, 0 to 3 percent A1-0 to 3 inches; very dark grayish brown (10YR 3/2) slopes, about 1 mile northwest of Lower Table Rock; gravelly loam, brown (10YR 5/3) dry; strong fine about 2,200 feet west and 440 feet south of the northeast granular structure; slightly hard, friable, slightly sticky corner of sec. 6, T. 36 S., R. 2 W. and slightly plastic; many very fine and common fine and medium roots; many very fine irregular pores; 25 Ap-0 to 7 inches; very dark grayish brown (10YR 3/2) silty percent gravel and 5 percent cobbles; moderately acid clay loam, grayish brown (10YR 5/2) dry; moderate fine (pH 5.8); abrupt smooth boundary. subangular blocky structure; hard, firm, sticky and A2-3 to 7 inches; dark brown (10YR 3/3) gravelly loam, light plastic; many very fine and fine roots; common fine yellowish brown (10YR 6/4) dry; strong fine granular irregular pores; slightly acid (pH 6.2); abrupt smooth structure; slightly hard, friable, slightly sticky and slightly boundary. plastic; many very fine, common fine and medium, and A-7 to 12 inches; very dark grayish brown (10YR 3/2) clay few coarse roots; many very fine irregular pores; 25 loam, grayish brown (10YR 5/2) dry; moderate fine percent gravel and 5 percent cobbles; strongly acid (pH subangular blocky structure; very hard, very firm, sticky 5.4); clear wavy boundary. and plastic; few very fine roots; many very fine irregular Bw-17 to 15 inches; brown (10YR 4/3) very gravelly clay pores; slightly acid (pH 6.2); clear smooth boundary. loam, light yellowish brown (10YR 6/4) dry; moderate BA-12 to 18 inches; very dark grayish brown (10YR 3/2) fine subangular blocky structure; slightly hard, friable, clay loam,- grayish brown (10YR 5/2) dry; moderate sticky and plastic; common very fine and few fine, medium subangular blocky structure; very hard, very medium, and coarse roots; common very fine tubular firm, sticky and plastic; few very fine roots; common fine pores; 30 percent gravel and 15 percent cobbles; tubular pores; slightly acid (pH 6.1); clear smooth strongly acid (pH 5.4); clear wavy boundary. boundary. Bw2-15 to 29 inches; light olive brown (2.5Y 5/4) very cobbly Bt1-18 to 29 inches; very dark grayish brown (10YR 3/2) clay loam, very pale brown (10YR 7/4) dry; moderate clay, grayish brown (10YR 5/2) dry; common distinct fine and medium angular blocky structure; hard, friable, mottles; moderate medium subangular blocky structure; sticky and plastic; common very fine and few fine and very hard, very firm, sticky and plastic; few very fine medium roots; common very fine tubular pores; 30 roots; few very fine tubular pores; common faint clay percent gravel and 20 percent cobbles; strongly acid films; moderately acid (pH 6.0); gradual wavy boundary. (pH 5.2); abrupt wavy boundary. Bt2-29 to 44 inches; dark grayish brown (2.5Y 4/2) clay, R-29 inches; fractured serpentinite. grayish brown (2.5Y 5/2) dry; many distinct yellowish red (5YR 4/6) mottles; strong coarse angular blocky The depth to bedrock is 20 to 40 inches. The structure; very hard, very firm, very sticky and very particle-size control section contains 35 to 60 percent plastic; few very fine tubular pores; common distinct clay films; moderately acid (pH 5.8); gradual wavy boundary. 2C-44 to 50 inches; dark grayish brown (2.5Y 4/3) sandy clay loam, light brownish gray (2.5Y 6/3) dry; many distinct yellowish red (5YR 4/6) mottles; massive; very common very fine tubular pores; 20 percent gravel hard, very firm, sticky and plastic; few very fine pores; and 30 percent cobbles and stones; moderately acid moderately acid (pH 5.8); gradual wavy boundary. 3Cr-50 (pH 5.6); clear wavy boundary. inches; weathered sandstone. Bt-23 to 42 inches; dark reddish brown (5YR 3/3) extremely gravelly clay loam, brown (7.5YR 4/4) dry; The soils are saturated to the surface for at least 1 moderate very fine and fine angular blocky structure; month in most years. The depth to bedrock is 40 to 60 hard, firm, sticky and plastic; few very fine, fine, and inches. The particle-size control section contains 35 to 45 medium roots; common very fine tubular pores; few percent clay. The mollic epipedon is 20 to 35 inches thick. faint clay films on faces of peds and in pores; 50 The A horizon has hue of 10YR or 2.5Y; value of 2 or 3 percent gravel and 20 percent cobbles; moderately moist, 3 to 5 dry; and chroma of 2 or 3 moist and dry. The Bt acid (pH 5.6); clear wavy boundary. horizon has hue of 10YR or 2.5Y; value of 3 or 4 moist, 4 or Cr-42 inches; weathered andesite. 5 dry; and chroma of 2 or 3 moist and dry. It is clay or clay loam. The 2C horizon has value of 4 or 5 moist, 5 or 6 dry, The depth to bedrock is 40 to 60 inches. The and chroma of 3 or 4 moist and dry. It is sandy clay loam or particle-size control section contains 35 to 75 percent clay loam. rock fragments and 27 to 35 percent clay. The mollic epipedon is 20 to 30 inches thick. Greystoke Series The A horizon has hue of 7.5YR, 5YR, or 2.5YR; value of 2 or 3 moist; and chroma of 2 or 3 moist, 3 or 4 dry. The BA The Greystoke series consists of deep, well drained horizon has hue of 7.5YR, 5YR, or 2.5YR and chroma of 2 soils on plateaus and hillslopes. These soils formed in to 4 moist, 3 or 4 dry. It is very cobbly loam, very gravelly colluvium and residuum derived from igneous rock. Slopes loam, or cobbly clay loam. The Bt horizon has hue of 7.5YR, are 1 to 75 percent. The mean annual precipitation is 5YR, or 2.5YR and chroma of 3 or 4 moist and dry. It is very about 25 inches, and the mean annual temperature is cobbly, very gravelly, or extremely gravelly clay loam. about 44 degrees F. Typical pedon of Greystoke stony loam, in an area of Heppsie Series Greystoke-Pinehurst complex, 12 to 35 percent north slopes; about 600 feet north and 1,300 feet east of the The Heppsie series consists of moderately deep, well southwest corner of sec. 32, T. 39 S., R. 7 E. drained soils on hillslopes. These soils formed in colluvium derived from igneous rock. Slopes are 35 to 70 percent. The Oi-2 inches to 0; needles and twigs. mean annual precipitation is about 30 inches, and the mean A1-0 to 3 inches; dark reddish brown (5YR 2.5/2) stony annual temperature is about 50 degrees F. loam, brown (7.5YR 4/3) dry; moderate very fine Typical pedon of Heppsie clay, 35 to 70 percent north granular structure; soft, very friable, slightly sticky and slopes, about 0.25 mile east of the Emigrant Reservoir; slightly plastic; many very fine and common fine, about 2,800 feet east and 100 feet south of the northwest medium, and coarse roots; many very fine irregular corner of sec. 28, T. 39 S., R. 2 E. pores; 5 percent gravel and 25 percent cobbles and stones; moderately acid (pH 5.8); abrupt smooth A1-0 to 7 inches; very dark brown (10YR 2/2) clay, dark boundary. grayish brown (10YR 4/2) dry; strong fine granular A2-3 to 13 inches; dark reddish brown (5YR 3/2) very cobbly structure; hard, friable, very sticky and very plastic; loam, brown (7.5YR 4/3) dry; moderate very fine and many fine and very fine roots; common fine irregular fine subangular blocky structure parting to moderate pores; 5 percent gravel and 5 percent cobbles; neutral fine granular; soft, very friable, slightly sticky and slightly (pH 6.8); clear smooth boundary. plastic; many very fine and common fine, medium, and A2-7 to 15 inches; very dark grayish brown (10YR 3/2) clay, coarse roots; many very fine irregular pores; 15 percent dark grayish brown (10YR 4/2) dry; moderate fine and gravel and 30 percent cobbles and stones; moderately very fine subangular blocky structure; hard, firm, very acid (pH 5.6); abrupt wavy boundary. sticky and very plastic; common fine and medium and BA-13 to 23 inches; dark reddish brown (5YR 3/3) very few large roots; common fine tubular pores; 10 percent cobbly loam, brown (7.5YR 4/4) dry; moderate very fine gravel; neutral (pH 6.8); clear smooth boundary. and fine angular blocky structure; hard, firm, slightly Bw-15 to 24 inches; dark brown (7.5YR 3/4) gravelly clay, sticky and slightly plastic; common very fine and few dark grayish brown (10YR 4/2) dry; weak fine, medium, and coarse roots; medium subangular blocky structure; very hard, firm, C-26 to 35 inches; dark yellowish brown (10YR 4/6) very sticky and very plastic; common fine and medium gravelly clay loam, yellowish brown (10YR 5/6) dry; and few large roots; common fine and very fine irregular massive; slightly hard, friable, sticky and plastic; pores; 20 percent gravel and 5 percent cobbles; slightly weakly smeary; few roots; many very fine irregular acid (pH 6.4); clear smooth boundary. pores; 15 percent hard gravel and 10 percent soft Cr-24 inches; saprolitic tuff. gravel; moderately acid (pH 5.8); clear irregular boundary. The depth to bedrock is 20 to 40 inches. The particle-size Cr-35 inches; highly weathered volcanic tuff and breccia. control section contains 40 to 55 percent clay and 15 to 35 percent rock fragments. In most years the soils have cracks The depth to bedrock is 20 to 40 inches. The that are open to the surface or to the base of the plow layer. particle-size control section contains 18 to 30 percent These cracks are at least 1 centimeter wide at a depth of 20 clay and 5 to 30 percent rock fragments. It has a bulk inches. The soils do not have intersecting slickensides. density of 0.50 to 0.85 gram per cubic centimeter. The A horizon has hue of 10YR or 7.5YR; value of 2 or 3 The A horizon has value of 2 or 3 moist, 3 or 4 dry, and moist, 3 or 4 dry; and chroma of 2 or 3 moist and dry. The chroma of 2 or 3 moist and dry. The Bw horizon has value Bw horizon has hue of 10YR or 7.5YR, value of 3 or 4 dry, of 2 or 3 moist, 3 to 5 dry, and chroma of 2 or 3 moist and and chroma of 2 to 4 moist and dry. dry. It is loam, clay loam, or gravelly clay loam. The C horizon, if it occurs, has hue of 7.5YR, 10YR, or 2.5Y; value Hobit Series of 4 or 5 moist, 4 to 7 dry; and chroma of 4 to 6 moist and dry. It is loam, clay loam, or gravelly clay loam. The Hobit series consists of moderately deep, well drained soils on hillslopes. These soils formed in Hoxie Series colluvium derived from igneous rock. Slopes are 12 to 60 percent. The mean annual precipitation is about 40 The Hoxie series consists of very deep, poorly drained inches, and the mean annual temperature is about 42 soils in basins. These soils formed in lacustrine material degrees F. containing some volcanic ash. Slopes are 0 to 1 percent. Typical pedon of Hobit loam, 12 to 35 percent north The mean annual precipitation is about 35 inches, and the slopes, about 1 mile north of Soda Mountain; about 1,910 mean annual temperature is about 42 degrees F. feet south and 1,350 feet east of the northwest corner of Typical pedon of Hoxie silt loam, 0 to 1 percent slopes, sec. 21, T. 40 S., R. 3 E. near Buck Lake; about 2,450 feet east and 50 feet north of the southwest corner of sec. 12, T. 38 S., R. 5 E. Oi-1 inch to 0; needles and twigs. A1-0 to 4 inches; very dark brown (10YR 2/2) loam, very A-0 to 10 inches; black (10YR 2/1) silt loam, gray (10YR dark grayish brown (10YR 3/2) dry; weak very fine 5/1) dry; moderate very fine subangular blocky granular structure; soft, very friable, nonsticky and structure; soft, friable, slightly sticky and plastic; many nonplastic; common very fine roots; many very fine fine and very fine roots; many very fine, fine, and irregular pores; 10 percent gravel; slightly acid (pH 6.5); medium irregular pores; slightly acid (pH 6.4); abrupt clear smooth boundary. smooth boundary. A2-4 to 18 inches; very dark brown (10YR 2/2) loam, dark BA-10 to 14 inches; black (10YR 2/1) silt loam, gray brown (10YR 3/3) dry; weak fine subangular blocky (10YR 5/1) dry; few fine faint yellowish brown (10YR structure parting to weak fine granular; soft, very friable, 5/6) mottles in root channels; moderate coarse and nonsticky and nonplastic; common fine and very fine medium prismatic structure; slightly hard, firm, slightly and few medium roots; many very fine irregular pores; sticky and plastic; common medium and fine roots; 10 percent gravel; slightly acid (pH 6.4); gradual wavy common very fine and fine discontinuous pores; boundary. slightly acid (pH 6.4); abrupt smooth boundary. Bw-18 to 26 inches; very dark brown (10YR 2/2) loam, Bw1-14 to 21 inches; grayish brown (2.5Y 5/2) silt loam, brown (10YR 4/3) dry; weak fine subangular blocky light gray (10YR 7/2) dry; common medium prominent structure parting to weak fine granular; soft, very friable, and distinct brown (7.5YR 4/4) and strong brown slightly sticky and slightly plastic; common very fine and (7.5YR 4/6, 5/6) mottles; moderate fine and few medium roots; many very fine irregular pores; 10 percent gravel; slightly acid (pH 6.2); clear irregular boundary. coarse prismatic structure; hard, firm, slightly sticky and of 3 to 5 moist, 5 to 8 dry; and chroma of 1 or 2 moist, 1 to plastic; common medium and fine roots; few very fine 4 dry. They are silt loam, very fine sandy loam, or silty clay discontinuous pores; slightly acid (pH 6.2); clear loam. smooth boundary. 2Bw2-21 to 28 inches; grayish brown (2.5Y 5/2) silt loam, Hukill Series light gray (10YR 7/2) dry; common medium prominent and distinct brown (7.5YR 4/4) and strong brown The Hukill series consists of deep, well drained soils on (7.5YR 5/6, 5/8) mottles; moderate coarse prismatic plateaus. These soils formed in residuum and colluvium structure; hard, friable, sticky and plastic; common derived from igneous rock. Slopes are 1 to 12 percent. The medium and fine roots; few very fine and fine mean annual precipitation is about 38 inches, and the mean discontinuous pores; accumulations of iron on pore annual temperature is about 49 degrees F. walls and in root channels; strongly acid (pH 5.4); clear Typical pedon of Hukill gravelly loam, 1 to 12 percent smooth boundary. slopes, about 2.5 miles east of Butte Falls; about 50 feet 2BC1-28 to 34 inches; grayish brown (10YR 5/2) very fine north and 50 feet west of the southeast corner of sec. 1, T. sandy loam, light gray (10YR 7/2) dry; common 35 S., R. 2 E. medium prominent and distinct brown (7.5YR 4/4), strong brown (7.5YR 5/6), and dark reddish brown Oi-1/2 inch to 0; needles, leaves, and twigs. (5YR 3/3) mottles; weak medium and fine subangular A-0 to 2 inches; dark reddish brown (5YR 3/2) gravelly blocky structure; slightly hard, friable, nonsticky and loam, dark reddish brown (5YR 3/3) dry; moderate very slightly plastic; common medium and fine roots; fine granular structure; slightly hard, friable, slightly common very fine discontinuous pores; accumulations sticky and slightly plastic; common medium and coarse of iron on pore walls and in root channels; 3 percent roots; many irregular pores; 25 percent gravel; slightly gravel; strongly acid (pH 5.4); clear smooth boundary. acid (pH 6.4); clear smooth boundary. 2BC2-34 to 44 inches; grayish brown (10YR 5/2) silt loam, AB-2 to 6 inches; dark reddish brown (5YR 3/3) gravelly light gray (10YR 7/2) dry; common medium prominent clay loam, dark reddish brown (5YR 3/4) dry; moderate and distinct strong brown (7.5YR 5/8), reddish brown very fine subangular blocky structure; slightly hard, (5YR 4/4), and yellowish red (5YR 5/6) mottles; friable, sticky and plastic; common medium and coarse massive or weak coarse prismatic structure; hard, roots; many very fine tubular pores; 25 percent gravel; friable, slightly sticky and plastic; common medium and slightly acid (pH 6.4); clear smooth boundary. fine roots; few very fine and fine discontinuous pores; Bt1-6 to 11 inches; dark reddish brown (2.5YR 3/4) gravelly accumulations of iron on pore walls and in root clay loam, reddish brown (5YR 4/4) dry; moderate very channels; strongly acid (pH 5.4); gradual smooth fine and fine subangular blocky structure; hard, friable, boundary. sticky and plastic; common medium and coarse roots; 2C-44 to 65 inches; grayish brown (10YR 5/2) silt loam, many very fine tubular pores; few faint clay films; 15 light gray (10YR 7/2) dry; variegated strong brown percent gravel; moderately acid (pH 6.0); clear wavy (7.5YR 4/6, 5/8) and yellowish red (5YR 4/6) mottles; boundary. massive; hard, friable, slightly sticky and plastic; few Bt2-11 to 20 inches; dark reddish brown (2.5YR 3/4) fine and very fine roots; few very fine and fine gravelly clay, reddish brown (5YR 4/4) dry; moderate discontinuous pores; common discontinuous iron fine subangular blocky structure; hard, firm, sticky and cementation; 3 percent gravel; strongly acid (pH 5.4). plastic; common very fine tubular pores; common faint and few distinct clay films; 15 percent gravel; few black The soils are saturated to the surface for at least a month stains; moderately acid (pH 5.8); gradual wavy in most years. The depth to bedrock is 60 inches or more. boundary. The mollic epipedon is 10 to 18 inches thick. The Bt3-20 to 33 inches; dark reddish brown (2.5YR 3/4) particle-size control section contains 18 to 30 percent clay gravelly clay, yellowish red (5YR 4/6) dry; moderate fine and less than 15 percent sand that is coarser than very fine subangular blocky structure; hard, firm, sticky and sand. Bulk density is 0.85 to 1.00 gram per cubic centimeter plastic; common medium roots; common very fine throughout the profile. tubular pores; common faint and few distinct clay films; The A and BA horizons have value of 2 or 3 moist and 15 percent gravel; common black stains; moderately chroma of 1 or 2 moist and dry. Dry value is 4 or 5 in the A acid (pH 5.6); gradual wavy boundary. horizon and 5 to 7 in the BA horizon. The 2Bw, 2BC, and 2Bt4-33 to 42 inches; dark reddish brown (2.5YR 3/4) 2C horizons have hue of 10YR or 2.5Y; value gravelly clay, yellowish red (5YR 4/6) dry; moderate medium subangular blocky structure; hard, firm, sticky Bw-16 to 24 inches; dark brown (10YR 4/3) very gravelly and plastic; common very fine tubular pores; common loam, light yellowish brown (10YR 6/4) dry; moderate faint clay films; 25 percent gravel; common black stains; fine subangular blocky structure; slightly hard, firm, strongly acid (pH 5.4); gradual wavy boundary. slightly sticky and slightly plastic; common fine and 2Crt-42 inches; saprolitic andesitic tuff; many faint red medium and few coarse roots; common fine tubular (2.5YR 4/6) clay films in fractures; common black stains. pores; 45 percent gravel and 10 percent cobbles; moderately acid (pH 5.6); abrupt wavy boundary. The depth to bedrock is 40 to 60 inches. The R-24 inches; highly fractured and partially weathered particle-size control section contains 35 to 45 percent metavolcanic rock. clay and 10 to 25 percent weathered gravel. The A horizon has hue of 5YR, 2.5YR, or 7.5YR; value The depth to bedrock is 20 to 40 inches. The of 3 to 5 dry; and chroma of 2 to 4 moist, 3 or 4 dry. The particle-size control section contains 35 to 80 percent 2Bt horizon has hue of 2.5YR moist, 2.5YR or 5YR dry, rock fragments and 18 to 30 percent clay. and chroma of 3 to 6 moist and dry. It is gravelly clay, clay, The A horizon has hue of 10YR or 7.5YR; value of 2 to 4 or gravelly clay loam. moist, 5 or 6 dry; and chroma of 2 to 4 moist and dry. The BA and Bw horizons have hue of 10YR or 7.5YR; value of Jayar Series 3 to 5 moist, 5 to 7 dry; and chroma of 3 to 6 moist and dry. They are very gravelly loam, very gravelly clay loam, The Jayar series consists of moderately deep, well extremely gravelly loam, or very cobbly loam. drained soils on hillslopes. These soils formed in colluvium derived from altered sedimentary and volcanic rock. Slopes Jayar Variant are 12 to 70 percent. The mean annual precipitation is about 50 inches, and the mean annual temperature is about The Jayar Variant consists of moderately deep, well 43 degrees F. drained soils on ridges and hillslopes. These soils formed Typical pedon of Jayar very gravelly loam, 45 to 70 in colluvium derived from altered sedimentary and volcanic percent north slopes, about 1 mile southeast of Anderson rock. Slopes are 5 to 35 percent. The mean annual Butte; about 1,000 feet south and 2,400 feet east of the precipitation is about 55 inches, and the mean annual northwest corner of sec. 12, T. 39 S., R. 2 W. temperature is about 42 degrees F. Typical pedon of Jayar Variant very gravelly loam, 5 to Oi-1 inch to 0; needles, leaves, and twigs. 35 percent slopes, about 1 mile northeast of King Mountain; A1-0 to 5 inches; very dark grayish brown (10YR 3/2) very about 1,900 feet east and 2,100 feet north of the southwest gravelly loam, grayish brown (10YR 5/2) dry; moderate corner of sec. 18, T. 33 S., R. 4 W. fine granular structure; soft, friable, slightly sticky and nonplastic; common fine and medium roots; many very A1-0 to 4 inches; very dark brown (10YR 2/2) very gravelly fine and fine irregular pores; 35 percent gravel and 5 loam, brown (10YR 4/3) dry; strong very fine granular percent cobbles; moderately acid (pH 5.8); abrupt structure; slightly hard, very friable, nonsticky and smooth boundary. nonplastic; many very fine and common fine, medium, A2-5 to 11 inches; dark brown (10YR 3/3) very gravelly and coarse roots; many irregular pores; 45 percent loam, pale brown (10YR 6/3) dry; moderate fine gravel and 10 percent cobbles; moderately acid (pH subangular blocky structure; slightly hard, slightly sticky 6.0); abrupt smooth boundary. and slightly plastic; common fine and medium roots; A2-4 to 8 inches; dark brown (10YR 3/3) very gravelly loam, common fine tubular pores; 35 percent gravel and 10 yellowish brown (10YR 5/4) dry; strong very fine and percent cobbles; moderately acid (pH 5.8); clear fine granular structure; slightly hard, friable, nonsticky smooth boundary. and nonplastic; many very fine, common fine and BA-11 to 16 inches; dark brown (10YR 4/3) very gravelly medium, and few coarse roots; many very fine tubular loam, light yellowish brown (10YR 6/4) dry; weak fine and irregular pores; 40 percent gravel and 10 percent subangular blocky structure; slightly hard, friable, cobbles; moderately acid (pH 6.0); clear wavy slightly sticky and slightly plastic; common fine and boundary. medium and few coarse roots; common fine tubular Bw-8 to 24 inches; dark yellowish brown (10YR 4/4) very pores; 40 percent gravel and 5 percent cobbles; cobbly loam, yellowish brown (10YR 5/4) dry; moderate moderately acid (pH 5.6); clear smooth boundary. very fine and fine subangular blocky structure; slightly hard, friable, slightly sticky and nonplastic; many very fine, common fine and medium, and few coarse roots; many very fine tubular Bt2-22 to 45 inches; reddish brown (5YR 4/4) gravelly clay pores; 20 percent gravel, 15 percent cobbles, and 5 loam, yellowish red (5YR 4/6) dry; moderate fine and percent stones; moderately acid (pH 5.6); abrupt wavy medium subangular blocky structure; hard, firm, sticky boundary. and plastic; common very fine and fine roots; common R-24 inches; metavolcanic rock. very fine and fine tubular pores; common distinct clay films in pores and on faces of peds; 20 percent gravel The depth to bedrock is 20 to 40 inches. The and 5 percent cobbles; moderately acid (pH 5.8); clear particle-size control section contains 35 to 80 percent broken boundary. rock fragments and 18 to 30 percent clay. Bt3-45 to 55 inches; reddish brown (5YR 4/4) gravelly clay The A horizon has hue of 10YR or 7.5YR; value of 2 to loam, yellowish red (5YR 4/6) dry; strong fine angular 4 moist, 4 to 6 dry; and chroma of 2 to 4 moist and dry. blocky structure; very hard, firm, sticky and plastic; few The Bw horizon has hue of 7.5YR or 10YR; value of 3 to 5 very fine and fine roots; common very fine and fine moist, 5 to 7 dry; and chroma of 3 to 6 moist and dry. It is tubular pores; many distinct clay films on faces of peds very gravelly loam, very gravelly clay loam, or very cobbly and in pores; 20 percent gravel and 10 percent cobbles; loam. strongly acid (pH 5.5); abrupt irregular boundary. Crt-55 inches; partially decomposed metavolcanic rock and Josephine Series schist; many distinct clay films in fracture planes.

The Josephine series consists of deep, well drained soils The depth to bedrock is 40 to 60 inches. The on hillslopes. These soils formed in colluvium and residuum particle-size control section contains 27 to 35 percent derived from altered sedimentary and volcanic rock. Slopes clay and 5 to 35 percent rock fragments. are 12 to 55 percent. The mean annual precipitation is The A horizon has hue of 5YR to 10YR; value of 2 to 4 about 45 inches, and the mean annual temperature is about moist, 5 or 6 dry; and chroma of 2 to 4 moist and dry. The 49 degrees F. Bt horizon has hue of 5YR, 2.5YR, or 7.5YR; value of 3 to 5 Typical pedon of Josephine gravelly loam, in an area of moist, 4 to 8 dry; and chroma of 4 to 6 moist and dry. It is Josephine-Speaker complex, 12 to 35 percent north slopes, dominantly clay loam or gravelly clay loam. In some about 0.75 mile northeast of Little Battle Mountain; about pedons, however, it is very gravelly clay loam below a depth 2,360 feet north and 750 feet west of the southeast corner of 40 inches. of sec. 3, T. 34 S., R. 3 W. Kanid Series Oi-1 inch to 0; leaves, needles, and twigs. A-0 to 3 inches; dark reddish brown (5YR 3/3) gravelly The Kanid series consists of deep, well drained soils on loam, dark brown (7.5YR 4/4) dry; weak fine granular hillslopes. These soils formed in colluvium derived from structure; soft, very friable, slightly sticky and slightly altered sedimentary and volcanic rock. Slopes are 50 to 80 plastic; many very fine and fine roots; many very fine percent. The mean annual precipitation is about 50 inches, and fine irregular pores; 20 percent gravel; slightly acid and the mean annual temperature is about 48 degrees F. (pH 6.4); abrupt smooth boundary. Typical pedon of Kanid very gravelly loam, in an area of AB-3 to 15 inches; dark reddish brown (5YR 3/4) gravelly Kanid-Atring very gravelly loams, 50 to 80 percent north loam, reddish brown (5YR 4/4) dry; weak fine and slopes, about 13.5 miles north of Wimer; about 1,200 feet medium granular structure; soft, very friable, slightly east and 700 feet south of the northwest corner of sec. 3, T. sticky and slightly plastic; many very fine and fine and 33 S., R. 4 W. common medium and coarse roots; many very fine and fine irregular pores; 15 percent gravel; slightly acid (pH Oi-1 inch to 0; needles, leaves, twigs, and roots. A-0 to 9 6.2); clear wavy boundary. inches; dark brown (10YR 3/3) very gravelly loam, Bt1-15 to 22 inches; dark reddish brown (5YR 3/4) gravelly brown (10YR 5/3) dry; strong very fine and fine granular clay loam, reddish brown (5YR 4/4) dry; weak very fine structure; slightly hard, very friable, slightly sticky and and fine subangular blocky structure; slightly hard, slightly plastic; common very fine, fine, medium, and friable, sticky and plastic; common very fine and fine coarse roots; many very fine and fine irregular pores; 50 and few medium and coarse roots; few very fine tubular percent gravel and 5 percent cobbles; moderately acid pores; very few faint clay films in pores and on rock (pH 5.6); clear wavy boundary. fragments; 20 percent gravel; moderately acid (pH 6.0); AB-9 to 18 inches; brown (10YR 4/3) very gravelly clear wavy boundary. loam, pale brown (10YR 6/3) dry; strong very fine and A2-5 to 10 inches; black (10YR 2/1) clay, very dark gray fine granular structure; slightly hard, very friable, (10YR 3/1) dry; weak medium prismatic structure slightly sticky and slightly plastic; common very fine, parting to strong fine subangular blocky; extremely hard, fine, medium, and coarse roots; many fine irregular very firm, very sticky and very plastic; many very fine pores; 45 percent gravel and 5 percent cobbles; roots; 5 percent gravel; slightly acid (pH 6.2); abrupt moderately acid (pH 5.6); abrupt wavy boundary. smooth boundary. Bw-18 to 29 inches; yellowish brown (10YR 5/4) very AB-10 to 20 inches; black (N 2/0) clay, very dark gray (N gravelly clay loam, light yellowish brown (10YR 6/4) 3/0) dry; moderate medium and coarse prismatic dry; moderate very fine and fine subangular blocky structure; extremely hard, very firm, very sticky and very structure; slightly hard, friable, slightly sticky and plastic; few fine roots; few intersecting slickensides; 5 slightly plastic; common very fine, fine, medium, and percent gravel; slightly acid (pH 6.4); clear wavy coarse roots; many very fine irregular pores; 40 percent boundary. gravel and 10 percent cobbles; moderately acid (pH Bw1-20 to 32 inches; black (N 2/0) and very dark gray (2.5Y 5.6); abrupt wavy boundary. 3/1) clay, very dark gray (N 3/0) and dark gray (2:5Y BC-29 to 47 inches; light olive brown (2.5Y 5/4) very 4/1) dry; massive; extremely hard, very firm, very sticky gravelly clay loam, pale yellow (2.5Y 7/4) dry; weak and very plastic; few fine roots; few intersecting very fine and fine subangular blocky structure; slightly slickensides; 5 percent gravel; slightly acid (pH 6.4); hard, friable, slightly sticky and slightly plastic; few very abrupt wavy boundary. fine, fine, medium, and coarse roots; many very fine Bw2-32 to 46 inches; very dark gray (2.5Y 3/1) clay, dark irregular pores; 40 percent gravel and 15 percent gray (2.5Y 4/1) dry; massive; very hard, firm, very sticky cobbles; strongly acid (pH 5.2); abrupt wavy boundary. and very plastic; few fine roots; common intersecting Cr-47 inches; highly fractured, metamorphosed sedimentary slickensides; slightly acid (pH 6.4); abrupt wavy rock. boundary. 2R-46 inches; gabbro. The depth to bedrock is 40 to 60 inches. The particle-size control section contains 50 to 80 percent The depth to bedrock is 40 to 60 inches. The soils are rock fragments and 22 to 30 percent clay. saturated to the surface for at least 1 month in most years. The A horizon has hue of 10YR or 7.5YR; value of 3 or 4 The particle-size control section contains 45 to 60 percent moist, 5 or 6 dry; and chroma of 2 to 4 moist and dry. The B clay. In most years the soils have cracks that are open to horizon has hue of 2.5Y, 1 OYR, or 7.5YR; value of 3 to 5 the surface or to the base of a plow layer. These cracks are moist, 5 to 7 dry; and chroma of 3 to 6 moist and dry. It is at least 1 centimeter wide at a depth of 20 inches. The soils very gravelly clay loam, very gravelly loam, or extremely have intersecting slickensides. gravelly loam. The A horizon has hue of 10YR or 2.5Y or is neutral in hue. It has value of 2 or 3 moist, 3 or 4 dry, and chroma of Kanutchan Series 0 or 1. The AB and Bw horizons are neutral in hue or have hue of 2.5Y to 7.5YR. They have value of 2 or 3 moist, 3 to The Kanutchan series consists of deep, somewhat 5 dry, and chroma of 0 or 1. poorly drained soils in basins. These soils formed in alluvium and colluvium derived from igneous rock. Slopes Kanutchan Variant are 1 to 8 percent. The mean annual precipitation is about 35 inches, and the mean annual temperature is The Kanutchan Variant consists of moderately deep, about 43 degrees F. moderately well drained soils in basins on plateaus. These Typical pedon of Kanutchan clay, 1 to 8 percent soils formed in alluvium derived from igneous rock. Slopes slopes, about 0.75 mile northeast of Shale City; about are 0 to 3 percent. The mean annual precipitation is about 2,700 feet east and 2,850 feet north of the southwest 18 inches, and the mean annual temperature is about 44 corner of sec. 10, T. 38 S., R. 2 E. degrees F. Typical pedon of Kanutchan Variant clay, in an area of A1-0 to 5 inches; black (10YR 2/1) clay, very dark gray Booth-Kanutchan Variant complex, 0 to 3 percent slopes; (10YR 3/1) dry; strong very fine subangular blocky about 1,550 feet north and 100 feet west of the southeast and fine granular structure; extremely hard, very firm, corner of sec. 10, T. 41 S., R. 6 E. very sticky and very plastic; many very fine roots; 5 percent gravel; slightly acid (pH 6.2); abrupt smooth A-0 to 3 inches; dark brown (7.5YR 3/3) clay, brown boundary. (7.5YR 4/2) dry; strong very fine angular blocky structure parting to strong thin and medium platy; hard, very firm, very sticky and very plastic; few very fine and fine roots; many very fine and fine structure; slightly hard, friable, slightly sticky and slightly irregular pores; moderately acid (pH 6.0); clear plastic; many roots; many fine irregular and few very smooth boundary. fine tubular pores; 5 percent gravel; slightly acid (pH Bw1-3 to 15 inches; dark reddish brown (5YR 3/3) clay, 6.5); clear smooth boundary. dark reddish brown (5YR 3/3) dry; strong coarse and Bw1-14 to 39 inches; dark brown (10YR 4/3) loam, brown very coarse prismatic and subangular blocky (10YR 5/3) dry; weak coarse prismatic structure; structure; very hard, very firm, very sticky and very slightly hard, firm, sticky and plastic; few fine roots; few plastic; few very fine, fine, medium, and coarse roots; fine tubular pores; 10 percent gravel; slightly acid (pH common very fine tubular pores; common intersecting 6.5); gradual smooth boundary. slickensides; slightly acid (pH 6.2); clear smooth Bw2-39 to 54 inches; dark brown (10YR 4/3) loam, boundary. yellowish brown (10YR 5/4) dry; weak coarse prismatic Bw2-15 to 21 inches; dark reddish brown (5YR 3/4) clay, structure; slightly hard, friable, sticky and plastic; few dark reddish brown (5YR 3/3) dry; strong coarse and fine roots; few fine tubular pores; 10 percent gravel; very coarse prismatic and subangular blocky slightly acid (pH 6.5); clear wavy boundary. structure; very hard, very firm, very sticky and very 2C-54 to 60 inches; dark brown (10YR 4/3) very gravelly plastic; few very fine, fine, medium, and coarse roots; sandy loam, yellowish brown (10YR 5/6) dry; massive; common very fine tubular pores; common intersecting slightly hard, friable, nonsticky and nonplastic; 35 slickensides; slightly acid (pH 6.2); abrupt smooth percent gravel; slightly acid (pH 6.5). boundary. R-21 inches; tuff. The depth to bedrock is 60 inches or more. The solum is 40 to 60 inches thick. The particle-size control section The depth to bedrock is 20 to 40 inches. The soils are contains 18 to 35 percent clay. saturated to the surface for at least 1 month in most years. The A horizon has hue of 10YR or 7.5YR; value of 3 or The particle-size control section contains 40 to 60 percent 4 moist, 4 to 6 dry; and chroma of 2 to 4 moist and dry. The clay. In most years the soils have cracks that are open to Bw horizon has hue of 10YR or 7.5YR; value of 3 or 4 the surface or to the base of a plow layer. These cracks are moist, 4 to 6 dry; and chroma of 4 to 6 moist and dry. It is at least 1 centimeter wide at a depth of 20 inches. The soils loam, clay loam, or gravelly loam. The 2C horizon, if it have intersecting slickensides. occurs, is stratified loam, sandy loam, or sand in the The A horizon has value of 2 or 3 moist, 3 or 4 dry, fine-earth fraction and contains 0 to 85 percent rock and chroma of 2 or 3 moist and dry. The Bw horizon has fragments, mostly gravel. value of 3 moist, 3 or 4 dry, and chroma of 3 or 4 moist and dry. Killet Series

Kerby Series The Killet series consists of very deep, well drained soils on plateaus and hillslopes. These soils formed in The Kerby series consists of very deep, well drained colluvium derived from igneous rock and containing and moderately well drained soils on stream terraces. volcanic ash. Slopes are 3 to 35 percent. The mean These soils formed in alluvium. Slopes are 0 to 3 percent. annual precipitation is about 45 inches, and the mean The mean annual precipitation is about 25 inches, and the annual temperature is about 43 degrees F. mean annual temperature is about 53 degrees F. Typical pedon of Killet gravelly loam, in an area of Typical pedon of Kerby loam, 0 to 3 percent slopes, Donegan-Killet gravelly loams, 12 to 35 percent north about 1 mile north of Central Point; about 500 feet north and slopes; about 1,500 feet east and 2,450 feet north of the 1,500 feet west of the southeast corner of sec. 35, T. 36 S., southwest corner of sec. 35, T. 33 S., R. 2 E. R. 2 W. Oi-2 inches to 0; leaves, needles, and twigs. Ap-0 to 7 inches; very dark grayish brown (10YR 3/2) loam, A1-0 to 8 inches; dark reddish brown (5YR 3/2) gravelly grayish brown (10YR 5/2) dry; strong fine granular loam, brown (7.5YR 4/2) dry; strong fine and medium structure; slightly hard, friable, slightly sticky and granular structure; soft, very friable, nonsticky and slightly plastic; many roots; many fine irregular pores; nonplastic; common very fine, fine, medium, and slightly acid (pH 6.5); abrupt smooth boundary. coarse roots; many very fine and fine irregular pores; BA-7 to 14 inches; dark brown (10YR 4/3) loam, pale brown 15 percent gravel; slightly acid (pH 6.5); abrupt smooth (10YR 6/3) dry; weak coarse prismatic boundary. A2-8 to 18 inches; dark reddish brown (5YR 3/2) gravelly loam, dark reddish gray (5YR 4/2) dry; moderate very fine and fine subangular blocky pores; slightly acid (pH 6.2); clear wavy boundary. structure; soft, friable, slightly sticky and slightly plastic; Bw1-11 to 20 inches; very dark gray (10YR 3/1) silty clay, common very fine, fine, medium, and coarse roots; gray (10YR 5/1) dry; strong coarse prismatic structure; common very fine tubular pores; 25 percent gravel and very hard, very firm, sticky and plastic; common very 7 percent cobbles; slightly acid (pH 6.4); clear wavy fine roots; many very fine tubular pores; slightly acid boundary. (pH 6.2); gradual wavy boundary. Bw1-18 to 38 inches; dark reddish brown (5YR 3/3) gravelly Bw2-20 to 37 inches; dark gray (10YR 4/1) silty clay, light clay loam, reddish brown (5YR 4/3) dry; moderate fine gray (10YR 6/1) dry; common medium prominent strong subangular blocky structure; slightly hard, friable, brown (7.5YR 4/6) mottles; weak coarse subangular slightly sticky and plastic; common very fine, fine, blocky structure; hard, very firm, sticky and plastic; few medium, and coarse roots; common very fine tubular very fine roots; many very fine tubular pores; pores; 25 percent gravel and 7 percent cobbles; slightly moderately acid (pH 5.8); gradual wavy boundary. acid (pH 6.2); clear wavy boundary. C1-37 to 49 inches; gray (10YR 5/1) silty clay loam, light Bw2-38 to 60 inches; dark reddish brown (5YR 3/3) clay gray (10YR 7/1) dry; common medium prominent strong loam, reddish brown (5YR 4/3) dry; moderate fine brown (7.5YR 4/6) mottles; massive; hard, firm, sticky subangular blocky structure; slightly hard, friable, and plastic; few very fine roots; many very fine and slightly sticky and plastic; few very fine, fine, and medium tubular pores; 3 percent gravel; moderately medium roots; common very fine tubular pores; 5 acid (pH 5.8); gradual wavy boundary. percent gravel; slightly acid (pH 6.2). C2-49 to 62 inches; gray (10YR 5/1) clay loam, light gray (10YR 7/1) dry; common medium prominent strong The depth to bedrock is 60 inches or more. The brown (7.5YR 4/6) mottles; massive; hard, firm, sticky particle-size control section contains 27 to 35 percent and plastic; few very fine roots; few very fine tubular clay and 10 to 35 percent rock fragments. The umbric pores; 5 percent gravel; moderately acid (pH 5.8). epipedon is 20 to 40 inches thick. The A horizon has hue of 10YR, 7.5YR, or 5YR; value of The soils are saturated to the surface for at least 1 month 2 or 3 moist, 3 to 5 dry; and chroma of 2 or 3 moist and dry. in most years. The depth to bedrock is 60 inches or more. The Bw horizon has hue of 7.5YR or 5YR; value of 3 or 4 The particle-size control section contains 35 to 45 percent moist, 4 or 5 dry; and chroma of 2 or 3 moist, 3 or 4 dry. It is clay. The mollic epipedon is 24 to 40 inches thick. The soils clay loam, gravelly clay loam, or cobbly clay loam. are characterized by an irregular decrease in content of organic matter to a depth of 50 inches. Klamath Series The A horizon has hue of 10YR or 7.5YR or is neutral in hue. It has value of 2 to 5 dry and chroma of 0 to 1 moist The Klamath series consists of very deep, poorly and dry. The B horizon has value of 2 to 4 moist, 4 to 7 dry, drained soils on flood plains. These soils formed in and chroma of 0 to 2 moist and dry. This horizon is mottled alluvium derived from igneous rock and volcanic ash. in pedons where dry value is 6 or more. It is silty clay or Slopes are 0 to 1 percent. The mean annual precipitation clay. The C horizon has value of 3 to 5 moist, 6 or 7 dry, is about 30 inches, and the mean annual temperature is and chroma of 0 to 2 moist, 0 or 1 dry. It is silty clay loam, about 44 degrees F. silty clay, or clay loam. Typical pedon of Klamath silt loam, 0 to 1 percent slopes, about 5 miles northeast of Pinehurst; about 1,500 Kubli Series feet west and 1,800 feet south of the northeast corner of sec. 18, T. 39 S., R. 5 E. The Kubli series consists of very deep, somewhat poorly drained soils on stream terraces. These soils A-0 to 3 inches; black (N 2/0) silt loam, black (10YR 2/1) formed in alluvium derived from granitic rock and are dry; strong fine granular structure; soft, very friable, underlain by older alluvium. Slopes are 0 to 7 percent. The nonsticky and nonplastic; many very fine and fine and mean annual precipitation is about 25 inches, and the common medium roots; many very fine irregular pores; mean annual temperature is about 52 degrees F. strongly acid (pH 5.2); abrupt smooth boundary. Typical pedon of Kubli loam, 0 to 3 percent slopes, BA-3 to 11 inches; black (N 2/0) clay, dark gray (10YR 4/1) about 1 mile southwest of Central Point; about 1,200 dry; strong coarse prismatic structure; hard, very firm, sticky and plastic; common very fine and few fine and medium roots; many very fine tubular feet south and 400 feet east of the northwest corner of sec. Langellain Series 15, T. 37 S., R. 2 W. The Langellain series consists of moderately deep, Ap-0 to 9 inches; very dark brown (10YR 2/2) loam, grayish moderately well drained soils on ridges, knolls, and brown (10YR 5/2) dry; massive; slightly hard, friable, hillslopes. These soils formed in colluvium and alluvium slightly sticky and slightly plastic; many very fine and derived from sedimentary rock. Slopes are 1 to 40 percent. fine roots; neutral (pH 6.8); abrupt smooth boundary. The mean annual precipitation is about 24 inches, and the A-9 to 15 inches; very dark grayish brown (10YR 3/2) loam, mean annual temperature is about 53 degrees F. grayish brown (10YR 5/2) dry; common fine faint dark Typical pedon of Langellain loam, in an area of brown (7.5YR 4/4) mottles; weak medium and coarse Langellain-Brader loams, 1 to 7 percent slopes, about 100 subangular blocky structure; hard, friable, slightly sticky feet west of an unnamed paved road in Sams Valley; and slightly plastic; few very fine and fine roots; many about 250 feet west and 1,350 feet south of the northeast very fine tubular pores; coatings that are light brownish corner of sec. 21, T. 35 S., R. 2 W. gray (10YR 6/2) dry; neutral (pH 6.8); clear smooth boundary. Oi-1/2 inch to 0; grasses, twigs, and leaves. Bw1-15 to 25 inches; dark grayish brown (10YR 4/2) loam, A1-0 to 6 inches; dark reddish brown (5YR 3/3) loam, brown brown (10YR 5/3) dry; common medium faint dark (10YR 5/3) dry; moderate fine granular structure; brown (7.5YR 4/4) and dark grayish brown (2.5Y 4/2) slightly hard, very friable, nonsticky and nonplastic; mottles; weak medium and coarse subangular blocky common fine roots; many fine irregular pores; slightly structure; hard, friable, slightly sticky and slightly plastic; acid (pH 6.2); abrupt smooth boundary. few fine roots; many very fine tubular pores; neutral (pH A2-6 to 10 inches; dark brown (7.5YR 3/4) loam, brown 6.8); gradual smooth boundary. (10YR 5/3) dry; moderate fine and very fine subangular Bw2-25 to 31 inches; dark gray ish brown (10YR 4/2) loam, blocky structure; slightly hard, very friable, nonsticky brown (10YR 5/3) dry; common medium and large and nonplastic; common fine roots; many fine and distinct reddish brown (5YR 4/4) mottles; weak medium medium irregular pores; moderately acid (pH 6.0); and coarse subangular blocky structure; very hard, abrupt irregular boundary. friable, slightly sticky and slightly plastic; few fine roots; Bt1-10 to 21 inches; strong brown (7.5YR 4/6) loam, brown many very fine tubular pores; neutral (pH 6.8); abrupt (7.5YR 5/4) dry; moderate fine subangular blocky smooth boundary. structure; hard, friable, slightly sticky and plastic; 2C1-31 to 47 inches; brown (10YR 4/3) clay, brown (10YR common fine and medium roots; many fine and medium 5/3) and light brownish gray (2.5Y 6/2) dry; massive; irregular pores; common faint clay films in pores and extremely hard, very firm, sticky and plastic; common few faint clay films on faces of peds; moderately acid very fine tubular pores; neutral (pH 6.6); clear smooth (pH 5.6); abrupt wavy boundary. boundary. Bt2-21 to 33 inches; brown (10YR 4/3) clay, grayish brown 2C2-47 to 60 inches; brown (10YR 4/3) clay loam that has (10YR 5/2) dry; common medium faint and distinct very dark grayish brown (2.5Y 3/2) coatings; light strong brown (7.5YR 5/6, 4/6) and brown (7.5YR 4/4) brownish gray (2.5Y 6/2, 10YR 6/2) and pale brown mottles, dominantly in the upper 3 inches; strong (10YR 6/3) dry; massive; hard, firm, slightly sticky and medium prismatic structure; extremely hard, firm, sticky slightly plastic; neutral (pH 6.8). and very plastic; few fine and medium roots; few fine tubular pores; common distinct clay films on faces of The depth to bedrock is 60 inches or more. Depth to the peds and in pores; strongly acid (pH 5.4); clear wavy clayey substratum is 25 to 35 inches, The upper part of the boundary. particle-size control section contains 18 to 25 percent clay, Bt3-33 to 38 inches; yellowish brown (10YR 5/4) clay, and the lower part contains 35 to 50 percent clay. grayish brown (10YR 5/2) dry; strong medium prismatic The A horizon has value of 2 or 3 moist and chroma of 1 structure; very hard, firm, sticky and very plastic; few or 2 moist, 2 or 3 dry. The Bw horizon has hue of 10YR or fine and medium roots; few fine tubular pores; common 2.5Y; value of 3 to 5 moist, 4 to 6 dry; and chroma of 2 or 3 distinct clay films on faces of peds and in pores; moist and dry. The 2C horizon has hue of 10YR or 2.5Y; strongly acid (pH 5.2); clear wavy boundary. value of 4 or 5 moist, 5 or 6 dry; and chroma of 2 or 3 moist 2Cr-38 inches; decomposed sandstone. and dry. It is clay loam or clay. The depth to bedrock is 20 to 40 inches. Depth to the clayey subsoil is 12 to 28 inches. The upper part of the particle-size control section contains 20 to 35 percent clay, and the lower part contains 45 to 60 percent clay. The A horizon has hue of 5YR, 7.5YR, or 10YR; value of 4 to 6 dry; and chroma of 2 to 4 moist and dry. The Bt horizon has hue of 5YR, 7.5YR, or 10YR; value of 3 to 5 moist, 4 to 6 dry; and chroma of 1 to 6 moist and dry. It is loam or clay loam. The 2Bt horizon has hue of 2.5Y, 10YR, or 7.5YR; value of 4 or 5 moist, 4 to 8 dry; and chroma of 1 to 6 moist and dry. It has faint to prominent mottles.

Lettia Series

The Lettia series consists of deep, well drained soils on hillslopes and old slump benches. These soils formed in colluvium and residuum derived from granitic rock (fig. 17). Slopes are 12 to 35 percent. The mean annual precipitation is about 50 inches, and the mean annual temperature is about 48 degrees F. Typical pedon of Lettia sandy loam, 12 to 35 percent south slopes, near Elderberry Flat along West Evans Creek; about 2,000 feet east and 2,500 feet north of the southwest corner of sec. 31, T. 33 S., R. 3 W.

Oi-2 inches to 0; twigs, needles, and leaves. A1-0 to 3 inches; dark brown (10YR 3/3) sandy loam, light yellowish brown (10YR 6/4) dry; strong very fine and fine granular structure; soft, very friable, nonsticky and nonplastic; many very fine and fine roots; many fine and medium irregular pores; 12 percent gravel; moderately acid (pH 5.6); abrupt smooth boundary. A2-3 to 8 inches; brown (7.5YR 4/4) loam, light brown (7.5YR 6/4) dry; moderate very fine and fine subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; common very fine, fine, and medium roots; common very fine and fine tubular pores; 5 percent gravel; strongly acid (pH 5.4); abrupt smooth boundary. Figure 17.-Profile of a Lettia sandy loam, which formed in AB-8 to 14 inches; reddish brown (5YR 4/4) loam, reddish colluvium and residuum derived from granitic rock. The yellow (7.5YR 7/6) dry; strong fine and medium surface layer is about 2 feet thick, and the subsoil extends to subangular blocky structure; hard, firm, sticky and a depth of about 6 feet. plastic; common very fine, fine, and medium roots; common very fine and fine tubular pores; 3 percent gravel; strongly acid (pH 5.2); clear smooth boundary. strongly acid (pH 5.2); clear smooth boundary. Bt1-14 to 26 inches; red (2.5YR 4/6) clay loam, yellowish Bt2--26 to 47 inches; red (2.5YR 4/8) loam, red (2.5YR 5/8) red (5YR 5/6) dry; strong fine and medium angular dry; moderate fine and medium subangular blocky blocky structure; very hard, firm, sticky and plastic; few structure; hard, firm, slightly sticky and slightly plastic; very fine, fine, and medium roots; few very fine tubular few very fine, fine, and medium roots; few very fine pores; common faint clay films on faces of peds and in tubular pores; common faint clay films on faces of peds pores; 2 percent gravel; and in pores; 5 percent gravel; strongly acid (pH 5.2); gradual wavy boundary. Bt3--47 to 55 inches; red (2.5YR 5/8) loam, reddish yellow, (5YR 6/6) and pink (5YR 7/4) dry; weak fine Bw2-34 to 41 inches; dark reddish brown (5YR 3/3) loam, and medium subangular blocky structure; hard, friable, brown (7.5YR 5/3) dry; weak medium and coarse slightly sticky and nonplastic; few faint clay films on subangular blocky structure; hard, firm, nonsticky and faces of peds; 2 percent gravel; strongly acid (pH 5.2). slightly plastic; few very fine, fine, medium, and coarse Cr-55 inches; decomposed granodiorite. roots; common very fine tubular pores; moderately acid (pH 5.6); abrupt wavy boundary. The depth to bedrock is 40 to 60 inches. The 2Bt-41 to 60 inches; dark brown (7.5YR 3/3) loam, brown particle-size control section contains 20 to 35 percent clay (7.5YR 4/4) and yellowish brown (10YR 5/4) dry; and 15 to 50 percent coarse sand and very coarse sand. moderate fine and medium subangular blocky structure; The A horizon has hue of 7.5YR or 10YR; value of 3 to 5 hard, firm, sticky and plastic; few very fine, fine, moist, 4 to 7 dry; and chroma of 2 to 4 moist and dry. The Bt medium, and coarse roots; common very fine pores; horizon has hue of 7.5YR, 5YR, or 2.5YR; value of 4 to 6 common faint clay films on faces of peds and in pores; moist, 5 to 7 dry; and chroma of 4 to 8 moist and dry. It is moderately acid (pH 5.6). loam, sandy clay loam, or clay loam. Some pedons have a C horizon. This horizon has hue of 10YR, 7.5YR, 5YR, or The depth to bedrock is 60 inches or more. The 2.5YR; value of 4 or 5 moist, 5 to 7 dry; and chroma of 4 to particle-size control section contains 10 to 18 percent 8 moist and dry. It is loam to coarse sandy loam. clay. The mollic epipedon is 20 to 45 inches thick. The A horizon has hue of 5YR, 7.5YR, or 10YR; value of Lobert Series 2 or 3 moist, 4 or 5 dry; and chroma of 2 or 3 moist and dry. The Bw and 2Bt horizons have hue of 10YR, 7.5YR, or 5YR; The Lobert series consists of very deep, well drained value of 3 or 4 moist, 4 to 6 dry; and chroma of 2 to 4 moist soils on stream terraces. These soils formed in alluvial and and dry. They are loam, fine sandy loam, or sandy loam. lacustrine sediment weathered from tuff and volcanic ash. Slopes are 0 to 12 percent. The mean annual precipitation Lorella Series is about 17 inches, and the mean annual temperature is about 44 degrees F. The Lorella series consists of shallow, well drained soils Typical pedon of Lobert sandy loam, 0 to 12 percent on hillslopes. These soils formed in colluvium and slopes, northwest of Round Lake; about 2,325 feet south residuum derived from igneous rock. Slopes are 15 to 35 and 1,900 feet west of the northeast corner of sec. 35, T. percent. The mean annual precipitation is about 18 inches, 38 S., R. 7 E. and the mean annual temperature is about 48 degrees F. Typical pedon of Lorella very stony loam, in an area of Oi-2 inches to 0; needles and twigs. Lorella-Skookum complex, 15 to 35 percent slopes, about A-0 to 10 inches; dark reddish brown (5YR 3/3) sandy loam, 4 miles southwest of Round Lake; about 2,325 feet east reddish brown (5YR 4/3) dry; moderate very fine and 1,000 feet north of the southwest corner of sec. 34, T. granular structure; soft, very friable, nonsticky and 39 S., R. 7 E. nonplastic; common very fine, fine, and medium and few coarse roots; many very fine pores; moderately acid A--O to 5 inches; very dark brown (10YR 2/2) extremely (pH 6.0); clear smooth boundary. stony loam, brown (10YR 4/3) dry; moderate very fine AB-10 to 20 inches; dark reddish brown (5YR 3/3) sandy granular structure; slightly hard, very friable, slightly loam, reddish brown (5YR 4/3) dry; moderate very fine sticky and slightly plastic; many very fine and common and fine subangular blocky structure; soft, very friable, fine and medium roots; many very fine pores; 30 nonsticky and nonplastic; common very fine, fine, and percent stones, 10 percent gravel, and 20 percent medium and few coarse roots; common very fine cobbles; moderately acid (pH 5.8); clear wavy tubular pores; moderately acid (pH 5.8); abrupt wavy boundary. boundary. BA-5 to 9 inches; very dark brown (10YR 2/2) very cobbly Bw1-20 to 34 inches; dark reddish brown (5YR 3/3) loam, clay loam, brown (10YR 4/3) dry; moderate very fine brown (7.5YR 5/3) dry; moderate fine and medium and fine subangular blocky structure; slightly hard, subangular blocky structure; hard, firm, nonsticky and friable, sticky and plastic; many very fine and common slightly plastic; few fine, medium, and coarse and fine and medium roots; many very fine tubular pores; 10 common very fine roots; common very fine tubular percent gravel and 25 percent cobbles; moderately acid pores; moderately acid (pH 5.6); clear wavy boundary. (pH 6.0); abrupt wavy boundary. Bt-9 to 17 inches; dark brown (7.5YR 3/2) very cobbly clay and medium subangular blocky structure; very hard, loam, brown (10YR 4/3) dry; moderate very fine and firm, very sticky and very plastic; few fine and medium fine subangular blocky structure; hard, friable, sticky roots; many fine and very fine tubular pores; common and plastic; common very fine, fine, and medium roots; faint and few distinct clay films on faces of peds and in many very fine tubular pores; many distinct clay films tubular pores; moderately acid (pH 6.0); clear wavy on faces of peds and in pores; 15 percent gravel and boundary. 20 percent cobbles; slightly acid (pH 6.2); abrupt wavy Bt3-28 to 45 inches; yellowish red (5YR 3/6) clay loam, boundary. yellowish red (5YR 4/6) dry; moderate fine subangular R-17 inches; tuff. blocky structure; very hard, firm, very sticky and very plastic; few medium roots; many very fine tubular pores; The depth to bedrock is 12 to 20 inches. The common faint and distinct clay films on faces of peds particle-size control section contains 35 to 50 percent and in tubular pores; few black stains; moderately acid clay and 35 to 60 percent rock fragments. (pH 5.8); clear smooth boundary. The A horizon has value of 2 or 3 moist, 4 or 5 dry, and Bt4-4.5 to 58 inches; yellowish red (5YR 3/6) clay loam, chroma of 2 or 3 moist and dry. The Bt horizon has hue of yellowish red (5YR 4/6) dry; weak medium subangular 10YR or 7.5YR; value of 2 to 4 moist, 4 to 6 dry; and blocky structure; very hard, firm, very sticky and very chroma of 2 to 4 moist and dry. It is very cobbly clay loam plastic; common very fine tubular pores; common faint or very cobbly clay. and few distinct clay films on faces of peds and in tubular pores; 5 percent partially weathered gravel; few Manita Series black concretions and common black stains; moderately acid (pH 5.7); abrupt wavy boundary. The Manita series consists of deep, well drained soils on Cr-58 inches; partially weathered siltstone. alluvial fans and hillslopes. These soils formed in alluvium and colluvium derived from altered sedimentary and The depth to bedrock is 40 to 60 inches. The volcanic rock. Slopes are 2 to 50 percent. The mean annual particle-size control section contains 35 to 45 percent precipitation is 30 inches, and the mean annual temperature clay. is about 50 degrees F. The A horizon has hue of 5YR, 7.5YR, or 10YR; value Typical pedon of Manita loam, in an area of Manita- of 3 or 4 moist, 4 to 6 dry; and chroma of 2 to 4 moist and Vannoy complex, 20 to 40 percent slopes, about 4 miles dry. The Bt horizon has hue of 2.5YR, 5YR, or 7.5YR; west of Phoenix; about 2,400 feet west and 2,000 feet value of 3 to 5 moist, 4 to 6 dry; and chroma of 4 to 6 moist south of the northeast corner of sec. 11, T. 38 S., R. 2 W. and dry. It is clay loam, silty clay, or clay.

A1-0 to 4 inches; dark brown (7.5YR 3/2) loam, brown McMullin Series (7.5YR 5/3) dry; moderate fine and very fine subangular blocky structure; slightly hard, friable, slightly sticky and The McMullin series consists of shallow, well drained slightly plastic; many very fine roots; many very fine soils on hillslopes and plateaus. These soils formed in tubular pores; slightly acid (pH 6.2); abrupt smooth colluvium derived from igneous rock and altered boundary. sedimentary rock. Slopes are 1 to 70 percent. The mean A2-4 to 8 inches; dark brown (7.5YR 3/3) loam, brown annual precipitation is about 30 inches, and the mean (7.5YR 5/3) dry; moderate medium and fine subangular annual temperature is about 50 degrees F. blocky structure; slightly hard, friable, slightly sticky and Typical pedon of McMullin gravelly loam, in an area of slightly plastic; many fine and very fine roots; many fine McMullin-Rock outcrop complex, 3 to 35 percent slopes, tubular pores; slightly acid (pH 6.2); clear smooth about 1 mile southeast of Butte Falls Highway; about boundary. 2,250 feet south and 1,150 feet east of the northwest Bt1-8 to 13 inches; dark reddish brown (5YR 3/4) clay loam, corner of sec. 8, T. 35 S., R. 1 E. brown (7.5YR 5/4) dry; moderate medium subangular blocky structure; hard, firm, sticky and plastic; common A1-0 to 2 inches; dark reddish brown (5YR 3/3) gravelly fine and very fine roots; many very fine tubular pores; loam, brown (7.5YR 4/4) dry; weak fine granular few faint dark reddish brown (5YR 3/5) clay films on structure; soft, very friable, slightly sticky and slightly faces of peds; moderately acid (pH 6.0); clear smooth plastic; many very fine roots; common very fine boundary. irregular pores; 20 percent gravel; slightly acid (pH Bt2-13 to 28 inches; yellowish red (5YR 3/6) clay loam, 6.3); clear smooth boundary. yellowish red (5YR 4/6) dry; moderate fine A2-2 to 7 inches; dark reddish brown (5YR 3/3) gravelly loam, dark brown (7.5YR 4/2) dry; moderate fine and loam, brown (7.5YR 4/4) dry; moderate fine subangular medium subangular blocky structure; hard, friable, blocky structure; slightly hard, very friable, slightly sticky and plastic; common very fine, fine, and medium sticky and slightly plastic; many very fine and fine roots; roots; common fine irregular and few very fine tubular many very fine and fine irregular and few fine tubular pores; few faint clay films on faces of peds and in pores; 15 percent gravel; slightly acid (pH 6.2); clear pores; 10 percent gravel; moderately acid (pH 6.0); smooth boundary. clear wavy boundary. Bw-7 to 17 inches; dark reddish brown (5YR 3/4) gravelly Bt2-12 to 25 inches; dark reddish brown (5YR 3/4) cobbly clay loam, reddish brown (5YR 4/4) dry; moderate clay, dark brown (7.5YR 3/4) dry; moderate medium medium subangular blocky structure; slightly hard, angular blocky structure; very hard, firm, very sticky friable,. sticky and plastic; few medium and many very and very plastic; common very fine, fine, and medium fine and fine roots; many very fine and fine irregular roots; common very fine irregular and common fine and few fine tubular pores; 15 percent gravel and 5 tubular pores; many distinct clay films on faces of peds percent cobbles; moderately acid (pH 6.0); abrupt and in pores; 10 percent gravel and 10 percent irregular boundary. cobbles; moderately acid (pH 5.8); gradual irregular R-17 inches; fractured andesite. boundary. Bt3-25 to 32 inches; dark reddish brown (5YR 3/4) cobbly The depth to bedrock is 12 to 20 inches. The clay, brown (7.5YR 4/4) dry; moderate medium angular particle-size control section contains 15 to 25 percent blocky structure; very hard, firm, very sticky and very rock fragments and 20 to 35 percent clay. plastic; common very fine, fine, and medium roots; The A horizon has hue of 5YR, 7.5YR, or 10YR; value common very fine irregular and common fine tubular of 2 or 3 moist, 4 or 5 dry; and chroma of 2 or 3 moist, 3 pores; many distinct clay films on faces of peds and in or 4 dry. The Bw horizon has hue of 5YR, 7.5YR, or pores; 10 percent gravel and 10 percent cobbles; 10YR; value of 3 or 4 moist, 4 to 6 dry; and chroma of 3 or moderately acid (pH 5.8); abrupt irregular boundary. 4 moist and dry. It is gravelly loam, gravelly clay loam, or Crt-32 inches; fractured andesite; many distinct dark brown cobbly clay loam. (5YR 4/4) clay films in fractures.

McNull Series The depth to bedrock is 20 to 40 inches. The particle-size control section contains 35 to 50 percent The McNull series consists of moderately deep, well clay and 10 to 35 percent rock fragments. drained soils on hillslopes. These soils formed in colluvium The A horizon has hue of 10YR, 7.5YR, or 5YR; value derived from igneous rock. Slopes are 12 to 60 percent. of 2 or 3 moist, 3 to 5 dry; and chroma of 2 or 3 moist and The mean annual precipitation is about 30 inches, and the dry. It is loam or gravelly loam. The Bt horizon has hue of mean annual temperature is about 50 degrees F. 10YR, 7.5YR, or 5YR; value of 3 to 5 moist and dry; and Typical pedon of McNull loam, 12 to 35 percent north chroma of 3 to 6 moist and dry. It is clay loam, clay, or slopes, about 5 miles northeast of Eagle Point; about 1,400 cobbly clay. feet south and 1,100 feet east of the northwest corner of sec. 8, T. 35 S., R. 1 E. Medco Series

Oi-1 inch to 0; leaves, needles, and twigs. The Medco series consists of moderately deep, A1-0 to 2 inches; dark reddish brown (5YR 3/3) loam, moderately well drained soils on hillslopes. These soils brown (7.5YR 4/2) dry; weak very fine granular formed in alluvium and colluvium derived from igneous structure; soft, very friable, slightly sticky and slightly rock. Slopes are 1 to 50 percent. The mean annual plastic; common very fine roots; many very fine and precipitation is about 30 inches, and the mean annual fine irregular pores; 10 percent gravel; slightly acid (pH temperature is about 50 degrees F. 6.4); abrupt smooth boundary. Typical pedon of Medco cobbly clay loam, in an area of A2-2 to 6 inches; dark reddish brown (5YR 3/3) loam, Medco-McMullin complex, 12 to 50 percent slopes, about brown (7.5YR 4/2) dry; moderate fine subangular 2.5 miles east of Brownsboro; about 2,255 feet east and blocky structure; slightly hard, very friable, sticky and 2,495 feet north of the southwest corner of sec. 35, T. 35 slightly plastic; common very fine and fine roots; many S., R. 1 E. very fine and fine irregular pores; 10 percent gravel; slightly acid (pH 6.1); clear wavy boundary. A1-0 to 2 inches; very dark brown (10YR 2/2) cobbly clay Bt1-6 to 12 inches; dark reddish brown (5YR 3/3) clay loam, dark gray (10YR 4/1) dry; weak fine and medium granular structure; slightly hard, very friable, slightly sticky and slightly plastic; common fine percent. The mean annual precipitation is about 25 and medium roots; many very fine irregular pores; 5 inches, and the mean annual temperature is about 53 percent gravel and 10 percent cobbles; neutral (pH 6.7); degrees F. . abrupt smooth boundary. Typical pedon of Medford silty clay loam, 0 to 3 A2-2 to 7 inches; very dark grayish brown (10YR 3/2) cobbly percent slopes, about 1 mile north of Central Point; clay loam, gray (10YR 5/1) dry; moderate fine and about 1,220 feet north and 580 feet east of the medium subangular blocky structure; slightly hard, southwest corner of sec. 35, T. 36 S., R. 2 W. friable, sticky and plastic; common fine and medium and few coarse roots; common very fine irregular and few Ap-0 to 8 inches; very dark brown (10YR 2/2) silty clay very fine tubular pores; 5 percent gravel and 10 percent loam, very dark grayish brown (10YR 3/2) dry; cobbles; neutral (pH 6.6); clear wavy boundary. moderate fine subangular blocky and granular structure; A3-7 to 12 inches; very dark grayish brown (10YR 3/2) and very hard, firm, sticky and plastic; many very fine roots; dark brown (10YR 3/3) cobbly clay loam, gray (10YR many very fine irregular pores; neutral (pH 6.6); abrupt 5/1) and grayish brown (10YR 5/2) dry; few fine faint smooth boundary. dark reddish brown (5YR 3/3) mottles; strong fine and A-8 to 12 inches; very dark brown (10YR 2/2) silty clay medium subangular blocky structure; hard, firm, sticky loam, dark grayish brown (10YR 4/2) dry; moderate and plastic; common medium and few fine and coarse medium subangular blocky structure; very hard, firm, roots; common very fine irregular and tubular pores; 10 sticky and plastic; many very fine roots; many very fine percent gravel and 10 percent cobbles; slightly acid (pH tubular pores; slightly acid (pH 6.4); clear smooth 6.1); abrupt smooth boundary. boundary. Bw1-12 to 22 inches; brown (10YR 5/3, 7.5YR 4/2) clay, Bt1-12 to 22 inches; very dark brown (10YR 2/2) silty clay, pale brown (10YR 6/3) and light brownish gray (10YR dark grayish brown (10YR 4/2) dry; moderate fine 6/2) dry; strong fine and medium angular blocky prismatic structure parting to moderate fine subangular structure; extremely hard, very firm, very sticky and very blocky; very hard, firm, very sticky and very plastic; few plastic; few medium and coarse roots; few very fine medium roots; many very fine tubular pores; many irregular pores; many prominent stress cutans; 5 distinct clay films on faces of peds; slightly acid (pH percent gravel; moderately acid (pH 5.9); gradual 6.4); clear smooth boundary. smooth boundary. Bt2-22 to 35 inches; dark brown (10YR 3/3) silty clay loam, 2Bw2-22 to 30 inches; brown (10YR 5/3) clay, very pale dark grayish brown (10YR 4/2) dry; weak fine prismatic brown (10YR 7/3) dry; strong medium angular blocky structure parting to moderate fine subangular blocky; structure; extremely hard, very firm, very sticky and very very hard, firm, sticky and very plastic; few medium plastic; few medium and coarse roots; few very fine roots; many very fine tubular pores; common distinct tubular pores; many prominent stress cutans; 5 percent very dark brown (10YR 2/2) clay films on faces of peds gravel; strongly acid (pH 5.3); abrupt irregular boundary. and in tubular pores; moderately acid (pH 6.4); gradual 3Cr-30 inches; partially weathered tuff. wavy boundary. Bt3-35 to 44 inches; dark yellowish brown (10YR 3/4) silty The depth to bedrock is 20 to 40 inches. Depth to the clay loam, dark grayish brown (10YR 4/2) dry; clayey subsoil is 6 to 18 inches. The particle-size control moderate medium subangular blocky structure; very section contains 50 to 60 percent clay and 5 to 30 percent hard, firm, sticky and very plastic; few medium roots; rock fragments. many very fine tubular pores; common faint dark brown The A horizon has hue of 7.5YR or 10YR and value of 2 (10YR 3/3) clay films on faces of peds and in tubular or 3 moist, 4 or 5 dry. It is clay loam or cobbly clay loam. pores; slightly acid (pH 6.4); gradual wavy boundary. The 2Bw horizon has hue of 7.5YR, 10YR, or 2.5Y; value of Bt4-4.4 to 53 inches; dark yellowish brown (10YR 3/4) clay 4 or 5 moist, 4 to 7 dry; and chroma of 2 to 4 moist, 2 or 3 loam, dark brown (10YR 4/3) dry; weak medium dry. It is clay or cobbly clay. subangular blocky structure; very hard, firm, sticky and very plastic; few medium roots; many very fine tubular Medford Series pores; common faint dark brown (10YR 3/3) clay films on faces of peds and in tubular pores; slightly acid (pH The Medford series consists of very deep, moderately 6.4); gradual wavy boundary. well drained soils on stream terraces. These soils formed in 2BCt-53 to 71 inches; dark yellowish brown (10YR 3/4) mixed alluvium derived from altered sedimentary and sandy clay loam, dark brown (10YR 4/3) dry; massive; volcanic rock. Slopes are 0 to 7 hard, firm, sticky and plastic; common fine tubular pores; few faint dark brown (10YR 3/3) clay The depth to bedrock is 10 to 20 inches. The films in tubular pores; slightly acid (pH 6.4). particle-size control section contains 60 to 70 percent clay and 0 to 15 percent rock fragments. The depth to bedrock is 60 inches or more. The The A horizon has hue of 7.5YR or 10YR; value of 2 or particle-size control section contains 35 to 45 percent 3 moist, 4 or 5 dry; and chroma of 2 or 3 moist, 1 to 3 dry. clay. The mollic epipedon is 20 to 40 inches thick. Some The Bt horizon has hue of 7.5YR or 10YR; value of 3 or 4 pedons have very gravelly layers below a depth of 40 moist, 4 or 5 dry; and chroma of 2 to 4 moist and dry. inches. The A horizon has value of 2 or 3 moist, 3 to 5 dry, and Musty Series chroma of 1 or 2 dry. It is clay loam or silty clay loam. The Bt horizon has value of 2 to 4 moist, 4 to 6 dry, and The Musty series consists of moderately deep, well chroma of 2 to 4 moist and dry. It is silty clay loam, clay, drained soils on ridges and hillslopes. These soils formed silty clay, or clay loam. The 2BC horizon, if it occurs, is in colluvium derived from altered volcanic rock. Slopes are sandy clay loam, clay loam, or silty clay loam in the 12 to 50 percent. The mean annual precipitation is about fine-earth fraction and contains 0 to 60 percent rock 45 inches, and the mean annual temperature is about 49 fragments. degrees F. Typical pedon of Musty gravelly loam, in an area of Merlin Series Musty-Goolaway complex, 12 to 35 percent slopes; about 650 feet west and 1,350 feet north of the southeast The Merlin series consists of shallow, well drained corner of sec. 13, T. 33 S., R. 3 W. soils on plateaus. These soils formed in residuum weathered from igneous rock. Slopes are 1 to 8 percent. Oi-1 inch to 0; needles and twigs. The mean annual precipitation is about 18 inches, and A1-0 to 3 inches; very dark grayish brown (10YR 3/2) the mean annual temperature is about 44 degrees F. gravelly loam, grayish brown (2.5Y 5/2) dry; strong fine Typical pedon of Merlin extremely stony loam, 1 to 8 granular structure; soft, very friable, nonsticky and percent slopes, about 1.5 miles southwest of Round Lake; nonplastic; many very fine and fine roots; many very about 1,225 feet west and 2,150 feet south of the northeast fine irregular pores; 15 percent gravel; moderately acid corner of sec. 14, T. 39 S., R. 7 E. (pH 5.8); clear smooth boundary. A2-3 to 12 inches; very dark grayish brown (2.5Y 3/2) A1-0 to 3 inches; dark brown (7.5YR 3/2) extremely stony gravelly loam, grayish brown (2.5Y 5/2) dry; moderate loam, brown (7.5YR 5/2) dry; moderate very fine very fine and fine subangular blocky structure; slightly subangular blocky structure; slightly hard, friable, hard, very friable, nonsticky and nonplastic; common nonsticky and nonplastic; common very fine roots; very fine, fine, and medium roots; many very fine common very fine irregular pores; 30 percent stones, 30 tubular pores; 20 percent gravel; moderately acid (pH percent cobbles, and 10 percent gravel; slightly acid 5.6); clear wavy boundary. (pH 6.1); clear smooth boundary. Bw-12 to 29 inches; dark grayish brown (2.5Y 4/2) very A2-3 to 11 inches; dark brown (7.5YR 3/3) extremely stony cobbly loam, light brownish gray (2.5Y 6/2) dry; weak loam, brown (7.5YR 5/3) dry; moderate very fine fine subangular blocky structure; slightly hard, friable, subangular blocky structure; slightly hard, friable, nonsticky and nonplastic; common very fine, fine, and slightly sticky and slightly plastic; common very fine medium roots; many very fine tubular pores; 20 percent roots; common very fine tubular pores; 30 percent cobbles and 30 percent gravel; moderately acid (pH stones, 30 percent cobbles, and 10 percent gravel; 5.6); abrupt wavy boundary. slightly acid (pH 6.1); abrupt wavy boundary. R-29 inches; fractured schist. Bt-11 to 13 inches; dark brown (7.5YR 3/4) clay, brown (7.5YR 5/4) dry; moderate fine angular blocky structure; The depth to bedrock is 20 to 40 inches. The very hard, very firm, sticky and plastic; common very particle-size control section contains 35 to 70 percent fine roots; common very fine tubular pores; many rock fragments and 15 to 25 percent clay. The umbric distinct clay films on faces of peds and in pores; 10 epipedon is 10 to 20 inches thick. percent gravel and 4 percent cobbles; slightly acid (pH The A horizon has hue of 10YR, 2.5Y, or 5Y; value of 2 or 6.1); abrupt wavy boundary. 3 moist, 3 to 5 dry; and chroma of 1 or 2 moist, 2 or 3 dry. R-13 inches; andesite. The Bw horizon has hue of 10YR, 2.5Y, or 5Y; value of 3 or 4 moist, 5 or 6 dry; and chroma of 2 or 3 moist and dry. It is very cobbly or extremely cobbly sandy loam, fine sand, or loamy sand. In some pedons, loam. however, it has gravelly or very gravelly layers below a depth of 40 inches. Newberg Series Norling Series The Newberg series consists of very deep, somewhat excessively drained soils on flood plains. These soils The Norling series consists of moderately deep, well formed in alluvium. Slopes are 0 to 3 percent. The mean drained soils on hillslopes. These soils formed in colluvium annual precipitation is about 30 inches, and the mean derived from altered sedimentary and volcanic rock. Slopes annual temperature is about 52 degrees F. are 35 to 55 percent. The mean annual precipitation is about Typical pedon of Newberg fine sandy loam, 0 to 3 50 inches, and the mean annual temperature is about 48 percent slopes, about 1 mile south of Upper Table Rock; degrees F. about 1,780 feet north and 1,500 feet east of the Typical pedon of Norling very gravelly loam, in an area southwest corner of sec. 12, T. 36 S., R. 2 W. of Norling-Acker complex, 35 to 55 percent south slopes; about 2,200 feet west and 1,600 feet south of the Ap-0 to 9 inches; very dark grayish brown (10YR 3/2) fine northeast corner of sec. 2, T. 33 S., R. 4 W. sandy loam, grayish brown (10YR 5/2) dry; single grain; loose, very friable, nonsticky and nonplastic; Oi-2 inches to 0; leaves, needles, twigs, and roots. many very fine roots; many very fine irregular pores; A1-0 to 5 inches; brown (10YR 4/3) very gravelly loam, moderately acid (pH 6.0); clear smooth boundary. brown (10YR 5/3) dry; strong fine granular structure; A-9 to 17 inches; very dark grayish brown (10YR 3/2) fine slightly hard, friable, nonsticky and nonplastic; many sandy loam, grayish brown (10YR 5/2) dry; weak very fine and fine, common medium, and few coarse medium subangular blocky structure; slightly hard, roots; many very fine irregular pores; 45 percent gravel friable, nonsticky and nonplastic; many very fine and and 5 percent cobbles; strongly acid (pH 5.4); abrupt fine roots; many very fine irregular pores; moderately smooth boundary. acid (pH 6.0); clear wavy boundary. A2-5 to 10 inches; brown (10YR 4/3) gravelly clay loam, C1-17 to 25 inches; dark brown (10YR 4/3) sandy loam, pale brown (10YR 6/3) dry; moderate very fine and fine pale brown (10YR 6/3) dry; massive; soft, very friable, subangular blocky structure; hard, friable, sticky and nonsticky and nonplastic; common fine roots; many plastic; many very fine, fine, and medium and few fine irregular pores; 10 percent gravel; slightly acid (pH coarse roots; many very fine tubular pores; 25 percent 6.2); gradual wavy boundary. gravel and 5 percent cobbles; moderately acid (pH 5.6); C2-25 to 30 inches; dark brown (10YR 4/3) sandy loam, clear wavy boundary. pale brown (10YR 6/3) dry; massive; soft, very friable, Bt1-10 to 22 inches; yellowish brown (10YR 5/4) gravelly nonsticky and nonplastic; common fine roots; many clay loam, light yellowish brown (10YR 6/4) dry; fine irregular pores; 10 percent gravel; slightly acid (pH moderate very fine and fine subangular blocky structure; 6.4); gradual wavy boundary. hard, friable, sticky and plastic; common very fine, fine, C3-30 to 42 inches; dark brown (10YR 4/3) fine sand, pale and medium roots; common very fine tubular pores; brown (10YR 6/3) dry; single grain; loose, nonsticky common faint clay films on faces of peds; 20 percent and nonplastic; common fine roots; many fine irregular gravel and 5 percent cobbles; moderately acid (pH 5.6); pores; 10 percent gravel; slightly acid (pH 6.2); clear clear wavy boundary. wavy boundary. Bt2-22 to 29 inches; yellowish brown (10YR 5/4) very cobbly C4-42 to 60 inches; dark grayish brown (10YR 4/2) loamy clay loam, light yellowish brown (10YR 6/4) dry; sand, pale brown (10YR 6/3) dry; single grain; loose, moderate very fine and fine subangular blocky structure; nonsticky and nonplastic; common irregular pores; 10 hard, friable, sticky and plastic; few very fine and fine percent gravel and 4 percent cobbles; slightly acid (pH roots; common very fine tubular pores; common faint 6.2). clay films on faces of peds; 20 percent gravel and 20 percent cobbles; moderately acid (pH 5.6); clear wavy The depth to bedrock is 60 inches or more. The boundary. particle-size control section contains 5 to 15 percent Cr-29 inches; highly fractured metavolcanic rock. clay. The mollic epipedon is 10 to 20 inches thick. The A horizon has value of 2 or 3 moist, 4 or 5 dry, and The depth to bedrock is 20 to 40 inches. The chroma of 2 or 3 moist and dry. The C horizon has hue of particle-size control section contains 18 to 35 percent 10YR or 7.5YR; value of 3 or 4 moist, 4 to 6 dry; and clay and 5 to 35 percent rock fragments. chroma of 2 to 4 moist and dry. It is dominantly The A horizon has hue of 10YR or 7.5YR; value of 2 to cobbly sandy loam, brown (7.5YR 5/4) dry; massive; 4 moist, 4 to 6 dry; and chroma of 2 to 4 moist, 3 or 4 dry. soft, very friable, nonsticky and nonplastic; few fine and The Bt horizon has hue of 10YR or 7.5YR; value of 3 to 5 medium roots; many very fine irregular pores; 15 moist, 5 or 6 dry; and chroma of 3 to 6 moist and dry. It is percent gravel and 25 percent cobbles; moderately acid gravelly clay loam, clay loam, or gravelly loam in the upper (pH 6.0). part and very cobbly clay loam, very gravelly clay loam, or very gravelly loam in the lower part. The depth to bedrock is 60 inches or more. The particle-size control section contains 35 to 70 percent Oatman Series rock fragments and 15 to 27 percent clay. The A horizon has hue of 10YR, 7.5YR, or 5YR; value of The Oatman series consists of very deep, well drained 3 or 4 moist, 3 to 5 dry; and chroma of 2 to 4 moist, 3 or 4 soils on plateaus and hillslopes. These soils formed in dry. The Bw horizon has hue of 10YR, 7.5YR, or 5YR; value colluvium and residuum derived from igneous rock and of 3 or 4 moist, 4 to 6 dry; and chroma of 3 or 4 moist and containing volcanic ash. Slopes are 0 to 65 percent. The dry. It is very cobbly sandy loam, very gravelly loam, or mean annual precipitation is about 35 inches, and the extremely cobbly loam. The C horizon has hue of 10YR, mean annual temperature is about 42 degrees F. 7.5YR, or 5YR; value of 3 or 4 moist, 4 to 6 dry; and chroma Typical pedon of Oatman cobbly loam, in an area of of 3 or 4 moist, 3 to 6 dry. It has textures similar to those of Oatman-Otwin complex, 0 to 12 percent slopes, about 8 the Bw horizon. miles northeast of Hyatt Reservoir; about 300 feet south and 330 feet west of the northeast corner of sec. 26, T. 38 Offenbacher Series S., R. 4 E. The Offenbacher series consists of moderately deep, well Oi-3 inches to 0; needles and twigs. drained soils on hillslopes. These soils formed in colluvium A-0 to 2 inches; dark brown (7.5YR 3/2) cobbly loam, dark derived from altered sedimentary and volcanic rock. Slopes brown (7.5YR 3/4) dry; weak very fine granular are 50 to 80 percent. The mean annual precipitation is about structure; soft, very friable, nonsticky and nonplastic; 32 inches, and the mean annual temperature is about 50 many very fine roots; many very fine irregular pores; 15 degrees F. percent gravel and 10 percent cobbles; slightly acid (pH Typical pedon of Offenbacher gravelly loam, in an area 6.5); abrupt smooth boundary. of Caris-Offenbacher gravelly loams, 50 to 80' percent north AB-2 to 16 inches; dark brown (7.5YR 3/4) cobbly loam, slopes, about 6 miles east of Ruch; about 900 feet north dark brown (7.5YR 4/4) dry; weak fine and medium and 75 feet east of the southwest corner of sec. 26, T. 38 subangular blocky structure; soft, very friable, nonsticky S., R. 2 W. and nonplastic; many very fine roots; many very fine irregular pores; 10 percent gravel and 15 percent Oi-1 inch to 0; leaves, needles, and twigs. cobbles; slightly acid (pH 6.5); clear smooth boundary. A-0 to 4 inches; dark grayish brown (10YR 4/2) gravelly Bw-16 to 30 inches; dark brown (7.5YR 3/4) very cobbly loam, light brownish gray (10YR 6/2) dry; moderate very sandy loam, dark brown (7.5YR 4/4) dry; weak fine and fine and fine subangular blocky structure; slightly hard, medium subangular blocky structure; soft, very friable, friable, slightly sticky and slightly plastic; many roots; nonsticky and nonplastic; common medium and coarse many irregular pores; 15 percent gravel; slightly acid and many very fine and fine roots; many very fine (pH 6.5); abrupt smooth boundary. irregular pores; 10 percent gravel and 30 percent BAt-4 to 9 inches; dark brown (7.5YR 4/4) gravelly loam, cobbles; slightly acid (pH 6.3); gradual wavy boundary. light brownish gray (10YR 6/2) dry; moderate very fine C1-30 to 42 inches; dark brown (7.5YR 3/4) very cobbly and fine subangular blocky structure; hard, friable, sandy loam, strong brown (7.5YR 4/6) dry; massive; slightly sticky and slightly plastic; many roots; many very soft, very friable, nonsticky and nonplastic; common fine tubular pores; few faint clay films on faces of peds; medium and coarse and many very fine and fine roots; 15 percent gravel; slightly acid (pH 6.3); clear wavy many very fine irregular pores; 10 percent gravel and boundary. 35 percent cobbles; slightly acid (pH 6.2); gradual wavy Bt1-9 to 21 inches; reddish brown (5YR 4/4) loam, pale boundary. brown (10YR 6/3) dry; moderate fine subangular blocky C2-42 to 60 inches; dark brown (7.5YR 4/4) very structure; hard, friable, sticky and plastic; many roots; many fine tubular pores; few faint clay films on faces of peds; 10 percent gravel; slightly acid (pH 6.2); gradual wavy boundary. Bt2-21 to 28 inches; yellowish red (5YR 4/6) loam, light brown (7.5YR 6/4) dry; moderate fine subangular cobbly sandy loam, yellowish brown (10YR 5/4) dry; blocky structure; very hard, firm, sticky and plastic; weak medium granular structure; appears massive common fine and medium roots; many fine tubular when wet; soft, very friable, nonsticky and nonplastic; pores; few faint clay films on faces of peds; common common roots; many irregular pores; 15 percent gravel black concretions 2 to 4 millimeters in diameter; slightly and 25 percent cobbles; slightly acid (pH 6.1); abrupt acid (pH 6.2); gradual wavy boundary. irregular boundary. Bt3-28 to 34 inches; yellowish red (5YR 4/6) loam, light R--28 inches; fractured andesite. brown (7.5YR 6/4) dry; moderate fine subangular blocky structure; very hard, firm, sticky and plastic; common The depth to bedrock is 20 to 40 inches. The fine roots; many very fine and fine tubular pores; few particle-size control section contains 35 to 60 percent rock faint clay films on faces of peds; 5 percent gravel; fragments and 10 to 18 percent clay. It has a bulk density slightly acid (pH 6.2); abrupt smooth boundary. of 0.85 to 0.95 gram per cubic centimeter. R-34 inches; fractured, metamorphosed volcanic rock. The A horizon has hue of 10YR or 7.5YR, value of 3 or 4 dry, and chroma of 2 to 4 moist, 3 or 4 dry. The Bw horizon The depth to bedrock is 20 to 40 inches. The has hue of 10YR or 7.5YR; value of 3 or 4 moist, 4 or 5 dry; particle-size control section contains 5 to 35 percent and chroma of 3 or 4 moist. It is very cobbly sandy loam or rock fragments and 18 to 30 percent clay. very cobbly loam. The A horizon has value of 3 or 4 moist, 4 to 6 dry, and chroma of 2 to 4 moist, 3 or 4 dry. The Bt horizon has hue Padigan Series of 10YR, 7.5YR, or 5YR; value of 4 or 5 moist, 5 or 6 dry; and chroma of 4 to 6 moist, 3 to 5 dry. It is loam, clay loam, The Padigan series consists of very deep, poorly gravelly loam, or gravelly clay loam. drained soils in basins. These soils formed in clayey alluvium derived from igneous rock. Slopes are 0 to 3 Otwin Series percent. The mean annual precipitation is about 24 inches, and the mean annual temperature is about 50 The Otwin series consists of moderately deep, well degrees F. drained soils on plateaus. These soils formed in colluvium Typical pedon of Padigan clay, 0 to 3 percent slopes, and residuum derived from igneous rock and containing about 2 miles north of Medford; about 1,950 feet east and volcanic ash. Slopes are 0 to 12 percent. The mean 850 feet north of the southwest corner of sec. 32, T. 36 S., annual precipitation is about 35 inches, and the mean R. 1 W. annual temperature is about 42 degrees F. Typical pedon of Otwin stony sandy loam, in an area of Ap-O to 6 inches; very dark gray (N 3/0) clay, very dark gray Oatman-Otwin complex, 0 to 12 percent slopes, about 3 (N 3/0) dry; strong fine and medium granular structure; miles west of Buck Lake; about 1,340 feet north and 2,592 extremely hard, firm, very sticky and very plastic; many feet west of the southeast corner of sec. 17, T. 38 S., R. 5 very fine roots; many fine irregular pores; mildly alkaline E. (pH 7.4); abrupt smooth boundary. A-6 to 12 inches; very dark gray (N 3/0) clay, very dark gray Oi-1 inch to 0; needles and twigs. (N 3/0) dry; moderate very coarse prismatic structure; A-0 to 3 inches; very dark grayish brown (10YR 3/2) stony extremely hard, firm, very sticky and very plastic; sandy loam, dark brown (10YR 4/3) dry; weak very fine common fine roots; many very fine irregular pores; granular structure; soft, very friable, nonsticky and mildly alkaline (pH 7.6); clear wavy boundary. nonplastic; many roots; many irregular pores; 15 ABk1-12 to 25 inches; very dark gray (N 3/0) clay, very dark percent gravel and 5 percent stones; slightly acid (pH gray (N 3/0) dry; moderate very coarse prismatic 6.5); clear smooth boundary. structure parting to strong medium angular blocky; BA-3 to 13 inches; dark yellowish brown (10YR 3/4) very extremely hard, firm, very sticky and very plastic; many cobbly sandy loam, dark brown (7.5YR 4/4) dry; weak prominent intersecting slickensides; common fine roots; fine and medium granular structure; soft, very friable, common very fine tubular pores; strongly effervescent; nonsticky and nonplastic; many roots; many irregular moderately alkaline (pH 8.0); gradual wavy boundary. pores; 15 percent gravel and 25 percent cobbles; ABk2-25 to 36 inches; very dark grayish brown (2.5Y 3/2) slightly acid (pH 6.3); gradual smooth boundary. clay, dark grayish brown (2.5Y 4/2) dry; moderate very Bw-13 to 28 inches; dark brown (7.5YR 3/4) very coarse prismatic structure parting to strong medium angular blocky; extremely hard, firm, very sticky and very plastic; many prominent loam, brown (7.5YR 4/4) dry; moderate fine granular intersecting slickensides; common fine distinct mottles; structure; soft, very friable, slightly sticky and slightly common fine roots; common very fine tubular pores; plastic; common very fine, fine, medium, and coarse soft accumulations of light gray (10YR 7/2) carbonates roots; many very fine irregular pores; 5 percent gravel that are violently effervescent; moderately alkaline (pH and 10 percent cobbles; strongly acid (pH 5.4); clear 8.4); clear wavy boundary. smooth boundary. Bk1-36 to 42 inches; grayish brown (2.5Y 5/2) clay, light AB-3 to 13 inches; dark reddish brown (5YR 3/3) cobbly gray (2.5Y 7/2) dry; massive; extremely hard, firm, very loam, brown (7.5YR 4/4) dry; moderate very fine and sticky and very plastic; many prominent intersecting fine subangular blocky structure; slightly hard, friable, slickensides; common fine distinct mottles; common fine slightly sticky and slightly plastic; common very fine, roots; few very fine tubular pores; soft accumulations of fine, medium, and coarse roots; many very fine tubular light gray (10YR 7/2) carbonates that are violently pores; 5 percent gravel and 10 percent cobbles; effervescent; strongly alkaline (pH 8.6); clear wavy moderately acid (pH 5.8); clear wavy boundary. boundary. Bt-13 to 25 inches; dark reddish brown (5YR 3/3) gravelly 2Bk2-42 to 60 inches; grayish brown (2.5Y 5/2) gravelly clay loam, brown (7.5YR 4/4) dry; moderate very fine sandy clay loam, light gray (2.5Y 7/2) dry; massive; and fine angular blocky structure; hard, firm, slightly hard, friable, sticky and plastic; common fine distinct sticky and slightly plastic; common very fine and few mottles; few fine roots; few fine irregular pores; 20 fine, medium, and coarse roots; common very fine percent gravel; violently effervescent; moderately tubular pores; common faint clay films on faces of peds; alkaline (pH 8.4). 10 percent hard gravel and 5 percent hard cobbles; 50 percent soft andesite fragments; moderately acid (pH The depth to bedrock is 60 inches or more. The soils are 6.0); clear wavy boundary. saturated to the surface for at least 1 month in most years. Cr-25 inches; weathered andesite. The particle-size control section contains 60 to 70 percent clay. The 2B horizon, if it occurs, is at a depth of more than The depth to bedrock is 20 to 40 inches. The 40 inches. It contains 15 to 25 percent gravel and 0 to 5 particle-size control section contains 27 to 35 percent clay, percent cobbles. In most years the soils have cracks that 10 to 35 percent hard rock fragments, and 25 to 65 are open to the surface or to the base of a plow layer. These percent soft rock fragments. The mollic epipedon is 20 to cracks are at least 1 centimeter wide at a depth of 20 40 inches thick. inches. The soils have intersecting slickensides. The A horizon has hue of 7.5YR or 5YR; value of 2 or 3 The A horizon has hue of 10YR or 2.5Y or is neutral in moist, 3 or 4 dry; and chroma of 2 or 3 moist, 3 or 4 dry. hue. It has value of 2 or 3 moist, 3 or 4 dry, and chroma of 0 The Bt horizon has hue of 7.5YR or 5YR, value of 4 or 5 or 1 moist and dry. The AB and B horizons have hue of dry, and chroma of 3 or 4 moist, 4 or 5 dry. It is clay loam, 2.5Y or 10YR or are neutral in hue. They have chroma of 0 cobbly clay loam, or gravelly clay loam. or 1 in pedons that do not have distinct mottles and lime concretions. The chroma ranges to 3 in pedons where Pearsoll Series mottles are distinct. The Pearsoll series consists of shallow, well drained Paragon Series soils on hillslopes. These soils formed in colluvium derived from serpentinitic rock. Slopes are 20 to 60 percent. The The Paragon series consists of moderately deep, well mean annual precipitation is about 50 inches, and the drained soils on plateaus and hillslopes. These soils mean annual temperature is about 49 degrees F. formed in colluvium and residuum derived from igneous Typical pedon of Pearsoll extremely stony clay loam, in rock. Slopes are 1 to 35 percent. The mean annual an area of Pearsoll-Dubakella complex, rocky, 20 to 60 precipitation is about 23 inches, and the mean annual percent slopes, about 13 miles north of Wimer; about 1,000 temperature is about 48 degrees F. feet west and 1,500 feet south of the northeast corner of Typical pedon of Paragon cobbly loam, in an area of sec. 4, T. 33 S., R. 4 W. Campfour-Paragon complex, 1 to 12 percent slopes; about 1,600 feet west and 2,450 feet north of the southeast Oi-1/2 inch to 0; leaves, needles, and twigs. corner of sec. 35, T. 40 S., R. 5 E. A-0 to 7 inches; dark brown (7.5YR 3/2) extremely stony clay loam, brown (7.5YR 4/4) dry; strong fine granular Oi-1 inch to 0; needles and twigs. structure; slightly hard, friable, sticky and A-0 to 3 inches; dark reddish brown (5YR 2/2) cobbly plastic; many very fine and common fine, medium, and firm, very sticky and very plastic; many intersecting coarse roots; common irregular pores; 15 percent gravel slickensides; common very fine and fine roots; common and 5 percent cobbles; stones covering 40 percent of very fine tubular pores; slightly acid (pH 6.4); diffuse the surface; slightly acid (pH 6.1); abrupt smooth smooth boundary. boundary. Bw1-20 to 33 inches; dark gray (N 4/0) clay, dark gray (N Bt1-7 to 15 inches; dark brown (7.5YR 3/4) very cobbly clay, 4/0) dry; moderate coarse and medium angular blocky brown (7.5YR 4/4) dry; moderate fine angular blocky structure; many intersecting slickensides; extremely structure; hard, friable, sticky and plastic; common very hard, firm, very sticky and very plastic; common fine fine, fine, medium, and coarse roots; common fine and roots; common very fine tubular pores; neutral (pH 7.2); very fine tubular pores; few faint clay films on faces of clear smooth boundary. peds; 15 percent gravel and 20 percent cobbles; slightly Bw2-33 to 40 inches; gray (2.5Y 5/1) clay, gray (2.5Y 5/1) acid (pH 6.1); abrupt wavy boundary. dry; moderate coarse and medium angular blocky Bt2-15 to 19 inches; dark brown (7.5YR 3/4) extremely structure; many intersecting slickensides; extremely cobbly clay, brown (7.5YR 5/4) dry; moderate fine hard, firm, very sticky and very plastic; common fine angular blocky structure; hard, friable, sticky and plastic; roots; common very fine tubular pores; mildly alkaline few very fine, fine, and medium roots; common fine and (pH 7.4); abrupt smooth boundary. very fine tubular pores; few faint clay films on faces of 2Cr-40 inches; decomposed sandstone. peds; 20 percent gravel and 50 percent cobbles; moderately acid (pH 6.1); abrupt irregular boundary. 'The depth to bedrock is 20 to 40 inches. The soils are R-19 inches; serpentinite. saturated to the surface for at least 1 month in most years. The particle-size control section contains 60 to 70 percent The depth to bedrock is 10 to 20 inches. The clay. In most years the soils have cracks that are open to particle-size control section contains 35 to 70 percent the surface or to the base of a plow layer. These cracks are rock fragments and 40 to 60 percent clay. at least 1 centimeter wide at a depth of 20 inches. The soils The A horizon has hue of 5YR or 7.5YR, value of 3 or 4 have intersecting slickensides. dry, and chroma of 2 or 3 moist, 3 or 4 dry. The Bt horizon The Ap and A horizons have hue of 10YR or 2.5Y, value has hue of 7.5YR, 5YR, or 2.5YR; value of 4 or 5 dry; and of 3.5 or 4 moist and dry, and chroma of 1 moist, 1 or 2 dry. chroma of 4 to 6 moist and dry. The Bw horizon has hue of 10YR or 2.5Y or is neutral in hue. It has value of 4 or 5 moist and dry and chroma of 0 to Phoenix Series 2 moist and dry.

The Phoenix series consists of moderately deep, poorly Pinehurst Series drained soils on alluvial fans. These soils formed in alluvium and colluvium derived from igneous rock. Slopes The Pinehurst series consists of very deep, well are 0 to 3 percent. The mean annual precipitation is about drained soils on plateaus and hillslopes. These soils 24 inches, and the mean annual temperature is about 53 formed in colluvium derived from igneous rock. Slopes are degrees F. 1 to 35 percent. The mean annual precipitation is about 35 Typical pedon of Phoenix clay, 0 to 3 percent slopes, inches, and the mean annual temperature is about 44 about 4 miles east of Central Point, about 750 feet east of degrees F. Sticky Lane and 200 feet south of a field road; about 2,400 Typical pedon of Pinehurst loam, 3 to 12 percent feet north and 750 feet east of the southwest corner of sec. slopes, about 0.75 mile east of Hyatt Lake; about 600 feet 33, T. 36 S., R. 1 W. north and 500 feet west of the southeast corner of sec. 11, T. 39 S., R. 3 E. Ap-0 to 3 inches; dark gray (10YR 4/1) clay, very dark gray (10YR 3.5/1) dry; strong fine granular structure; Oi-1 inch to 0; needles and twigs. extremely hard, firm, very sticky and very plastic; A1-0 to 4 inches; dark reddish brown (5YR 2/2) loam, dark common very fine and fine roots; many irregular pores; brown (7.5YR 3/3) dry; moderate very fine granular slightly acid (pH 6.4); abrupt smooth boundary. structure; slightly hard, friable, slightly sticky and slightly A-3 to 20 inches; dark gray (10YR 4/1) clay, dark gray plastic; common fine and very fine roots; many irregular (10YR 4/1) dry; massive or cloddy in the upper 4 inches pores; 10 percent gravel; slightly acid (pH 6.4); clear and moderate coarse and medium angular blocky smooth boundary. structure in the lower part; extremely hard, A2--4 to 15 inches; dark reddish brown (5YR 2/2) loam, very dark grayish brown (10YR 3/2) crushed, dark reddish brown (5YR 3/3) dry; moderate very fine subangular blocky structure; slightly hard, friable, structure; very soft, very friable, nonsticky and slightly sticky and slightly plastic; common fine and nonplastic; many very fine roots; many very fine pores; coarse roots; many very fine tubular pores; 10 percent slightly acid (pH 6.5); abrupt smooth boundary. gravel; slightly acid (pH 6.2); clear smooth boundary. A2-2 to 8 inches; dark reddish brown (5YR 3/3) loam, BAt-15 to 21 inches; dark reddish brown (5YR 3/3) clay reddish brown (5YR 4/3) dry; weak very fine granular loam, reddish brown (5YR 4/3) dry; moderate very fine structure; soft, very friable, slightly sticky and slightly and fine subangular blocky structure; hard, friable, sticky plastic; many very fine and coarse roots; many very fine and plastic; common fine and coarse roots; many very tubular pores; slightly acid (pH 6.5); gradual wavy fine tubular pores; few faint clay films; 10 percent gravel; boundary. moderately acid (pH 6.0); clear wavy boundary. BA-8 to 16 inches; dark reddish brown (5YR 3/3) clay loam, Bt-21 to 41 inches; dark reddish brown (5YR 3/4) clay loam, reddish brown (5YR 5/3) dry; weak medium subangular reddish brown (5YR 4/4) rubbed, dark brown (7.5YR blocky structure parting to moderate fine granular; 4/4) dry; moderate medium subangular blocky structure; slightly hard, friable, sticky and slightly plastic; many hard, firm, sticky and plastic; few medium and coarse fine and coarse roots; many very fine tubular pores; roots; many very fine tubular pores; common faint clay slightly acid (pH 6.4); clear smooth boundary. films; 10 percent partially weathered gravel; moderately Bw1-16 to 26 inches; dark reddish brown (5YR 3/3) gravelly acid (pH 5.8); gradual wavy boundary. clay, reddish brown (5YR 5/3) dry; weak fine and BCt-41 to 60 inches ; dark reddish brown (5YR 3/4) clay medium subangular blocky structure; hard, firm, sticky loam, brown (7.5YR 5/4) dry; weak coarse subangular and plastic; many fine and few coarse roots; many very blocky structure; hard, friable, sticky and plastic; few fine tubular pores; 15 percent gravel (mainly at a depth medium roots; common very fine tubular pores; few faint of 24 to 26 inches); slightly acid (pH 6.3); gradual clay films; 5 percent partially weathered gravel and 10 smooth boundary. percent partially weathered cobbles; strongly acid (pH 2Bw2-26 to 38 inches; dark reddish brown (5YR 3/3) 5.4). gravelly clay, brown (7.5YR 5/3) dry; moderate medium subangular blocky structure; hard, firm, sticky and The depth to bedrock is 60 inches or more. The plastic; few fine and coarse roots; many very fine particle-size control section contains 20 to 35 percent clay tubular pores; 15 percent gravel and 5 percent cobbles; and 5 to 35 percent partially weathered rock fragments. The slightly acid (pH 6.1); clear wavy boundary. mollic epipedon is 20 to 30 inches thick. 2C-38 to 52 inches; dark reddish brown (5YR 3/3) and The A horizon has hue of 10YR, 7.5YR, or 5YR; value reddish brown (5YR 4/4) gravelly clay, reddish brown of 2 or 3 moist, 3 to 5 dry; and chroma of 2 or 3 moist, 2 to (5YR 4/3) dry; massive; firm, sticky and plastic; few fine 4 dry. The Bt horizon has hue of 10YR, 7.5YR, or 5YR; and coarse roots; common very fine tubular pores; 15 value of 3 to 5 moist, 4 to 6 dry; and chroma of 2 to 4 percent gravel and 5 percent cobbles; moderately acid moist and dry. It is loam, clay loam, gravelly clay loam, or (pH 5.8); abrupt wavy boundary. cobbly clay loam. 3Cr-52 inches; partially weathered andesite.

Pokegema Series The depth to bedrock is 40 to 60 inches. The particle-size control section contains 35 to 55 percent The Pokegema series consists of deep, well drained clay and 5 to 35 percent rock fragments. The mollic soils on plateaus and hillslopes. These soils formed in epipedon is 16 to 32 inches thick. colluvium and residuum derived from igneous rock. Slopes The A horizon has hue of 7.5YR, 5YR, or 2.5YR; value are 1 to 35 percent. The mean annual precipitation is about of 2 or 3 moist, 4 dry; and chroma of 2 to 4 moist and dry. 30 inches, and the mean annual temperature is about 43 The 2Bw and 2C horizons have hue of 7.5YR, 5YR, or degrees F. 2.5YR; value of 3 or 4 moist, 4 to 6 dry; and chroma of 2 to Typical pedon of Pokegema loam, in an area of 4 moist, 2 to 6 dry. They are clay, gravelly clay loam, or Pokegema-Woodcock complex, 1 to 12 percent slopes, gravelly clay. about 10 miles east of Pinehurst; about 35 feet south of the northeast corner of sec. 1, T. 40 S., R. 5 E. Pollard Series

Oi-1/2 inch to 0; needles, leaves, and twigs. The Pollard series consists of very deep, well drained A1-0 to 2 inches; dark reddish brown (5YR 2/2) loam, dark soils on alluvial fans and hillslopes. These soils formed brown (7.5YR 4/2) dry; weak very fine granular in alluvium and colluvium derived from altered particle-size control section contains 35 to 50 percent sedimentary and volcanic rock. Slopes are 2 to 35 clay. percent. The mean annual precipitation is about 45 The A horizon has hue of 7.5YR, 5YR, or 2.5YR; value of inches, and the mean annual temperature is about 49 3 or 4 moist, 4 or 5 dry; and chroma of 3 or 4 moist, 3 to 6 degrees F. dry. The Bt horizon has hue of 2.5YR or 5YR, value of 3 or Typical pedon of Pollard loam, in an area of 4 moist (4 or 5 dry in the upper part and 5 dry in the lower Josephine-Pollard complex, 12 to 35 percent south part), and chroma of 4 to 6 moist and dry. It is clay, silty slopes; about 1,600 feet west and 500 feet north of the clay, or clay loam. Some pedons have as much as 50 southeast corner of sec. 3, T. 34 S., R. 3 W. percent rock fragments in the BCt horizon or below the control section. Oi-2 inches to 0; leaves, twigs, needles, cones, and grass. Provig Series A1-0 to 3 inches; dark brown (7.5YR 3/3) loam, brown (7.5YR 4/4) dry; moderate fine granular structure; The Provig series consists of very deep, well drained slightly hard, friable, slightly sticky and slightly plastic; soils on dissected fan terraces. These soils formed in many fine and very fine roots; many fine, medium, and stratified alluvium. Slopes are 5 to 35 percent. The mean coarse irregular pores; 10 percent gravel; moderately annual precipitation is about 24 inches, and the mean acid (pH 5.6); abrupt smooth boundary. annual temperature is about 53 degrees F. A2-3 to 11 inches; dark brown (7.5YR 3/4) loam, brown Typical pedon of Provig very gravelly loam, in an area of (7.5YR 4/4) dry; moderate fine granular structure; Provig-Agate complex, 5 to 15 percent slopes, about 3.5 slightly hard, friable, slightly sticky and slightly plastic; miles north of Central Point; about 2,000 feet west and many fine and very fine roots; many irregular pores; 10 2,320 feet north of the southeast corner of sec. 21, T. 36 percent gravel; moderately acid (pH 5.6); clear smooth S., R. 2 W. boundary. AB-11 to 18 inches; dark reddish brown (5YR 3/4) clay Oi-1 inch to 0; leaves. loam, reddish brown (5YR 4/4) dry; strong fine and A1-0 to 3 inches; very dark brown (10YR 2/2) very gravelly medium subangular blocky structure; hard, firm, slightly loam, very dark grayish brown (10YR 3/2) dry; sticky and slightly plastic; common fine and very fine moderate fine subangular blocky structure parting to and few medium roots; common tubular pores; 10 moderate very fine granular; soft, very friable, slightly percent gravel; moderately acid (pH 5.6); clear smooth sticky and nonplastic; many fine and very fine roots; boundary. many fine irregular pores; 35 percent gravel; slightly Bt1-18 to 36 inches; dark reddish brown (5YR 3/4) clay acid (pH 6.1); clear smooth boundary. loam, reddish brown (5YR 4/4) dry; strong medium A2-3 to 9 inches; very dark grayish brown (10YR 3/2) very and coarse subangular blocky structure; hard, very gravelly loam, dark grayish brown (10YR 4/2) dry; firm, sticky and plastic; few very fine, fine, medium, moderate fine subangular blocky structure; slightly and coarse roots; few tubular pores; common faint hard, friable, slightly sticky and slightly plastic; common and many distinct clay films; 10 percent gravel; very fine and few fine roots; many very fine tubular moderately acid (pH 5.6); gradual smooth boundary. pores; 50 percent gravel and 5 percent cobbles; Bt2-36 to 45 inches; yellowish red (5YR 4/6) clay loam, neutral (pH 6.6); clear smooth boundary. reddish brown (5YR 5/4) dry; moderate medium and Bt-9 to 15 inches; dark brown (7.5YR 3/2) very gravelly clay coarse subangular blocky structure; hard, very firm, loam, dark brown (10YR 3/3) crushed, brown (7.5YR sticky and plastic; few very fine and coarse roots; few 4/2) dry; moderate fine subangular blocky structure; tubular pores; common faint and many distinct clay hard, friable, sticky and plastic; many very fine tubular films; 10 percent gravel; moderately acid (pH 5.6); pores; common distinct clay films on faces of peds and gradual wavy boundary. in pores; common clay bridges; 45 percent gravel and BCt-45 to 61 inches; brown (7.5YR 4/4) clay loam, brown 5 percent cobbles; neutral (pH 6.6); abrupt smooth (7.5YR 5/4) dry; weak medium and coarse boundary. subangular blocky structure; hard, firm, sticky and 2C-15 to 60 inches; variegated dark reddish brown (5YR plastic; few medium and coarse roots; few tubular 3/3, 3/4) and reddish brown (5YR 4/4, 5/4) extremely pores; many distinct clay films; 15 percent soft gravelly clay that has lenses of coarser textured gravel; strongly acid (pH 5.4). material; massive; very hard, firm, very sticky and very plastic; common black stains; 70 The depth to bedrock is 60 inches or more. The percent gravel and 5 percent cobbles; neutral (pH or 4 moist, 4 to 6 dry; and chroma of 3 or 4 moist and dry. 6.8). It is silt loam or loam in the lower part.

The depth to bedrock is 60 inches or more. The Reinecke Series thickness of the solum and depth to the 2C horizon are 14 to 20 inches. The particle-size control section contains 35 The Reinecke series consists of very deep, well to 45 percent clay and 35 to 60 percent rock fragments. drained soils on plateaus. These soils formed in volcanic The A horizon has hue of 10YR or 7.5YR; value of 2 or 3 ash over residuum weathered from igneous rock. Slopes moist, 3 or 4 dry; and chroma of 2 or 3 moist and dry. The are 0 to 5 percent. The mean annual precipitation is Bt horizon has value of 4 or 5 dry and chroma of 2 or 3 about 45 inches, and the mean annual temperature is moist and dry. It is very gravelly clay loam or very gravelly about 48 degrees F. clay. The 2C horizon has variegated colors. It is extremely Typical pedon of Reinecke sandy loam, in an area of gravelly clay or extremely gravelly clay loam and contains Reinecke-Coyata complex, 0 to 5 percent slopes, about 4 60 to 90 percent rock fragments. miles east of Prospect; about 2,275 feet east and 775 feet south of the northwest corner of sec. 25, T. 32 S., R. 3 E. Randcore Series Oi-2 inches to 0; needles and twigs. The Randcore series consists of very shallow, A1-0 to 3 inches; dark brown (7.5YR 3/2) sandy loam, brown moderately well drained soils on plateaus. These soils are (10YR 4/3) dry; weak fine granular structure; soft, very between mounds in areas of patterned ground. They formed friable, nonsticky and nonplastic; many very fine and in loess over igneous rock. Slopes are 0 to 5 percent. The fine and common medium and coarse roots; many very mean annual precipitation is about 22 inches, and the mean fine irregular pores; 10 percent gravel-sized pumice; annual temperature is about 49 degrees F. slightly acid (pH 6.4); abrupt smooth boundary. Typical pedon of Randcore extremely stony loam, in an A2-3 to 9 inches; dark brown (7.5YR 3/4) sandy loam, brown area of Randcore-Shoat complex, 0 to 5 percent slopes, (7.5YR 4/4) dry; weak fine granular structure; soft, very about 1 mile east of the intersection of Copco Road and friable, nonsticky and nonplastic; common very fine, the Oregon-California State line; about 100 feet west of fine, medium, and coarse roots; many very fine irregular the southeast corner of sec. 10, T. 41 S., R. 4 E. pores; 10 percent gravel-sized pumice; moderately acid (pH 6.0); abrupt wavy boundary. A1-0 to 1 inch; dark brown (7.5YR 3/4) extremely stony Bw-9 to 25 inches; brown (7.5YR 4/4) gravelly sandy loam, loam, brown (7.5YR 5/4) dry; weak medium platy brown (7.5YR 5/4) dry; weak very fine and fine structure; soft, very friable, nonsticky and nonplastic; subangular blocky structure; soft, very friable, nonsticky few very fine roots; common very fine vesicular pores; and nonplastic; common very fine, fine, medium, and 60 percent stones and 5 percent gravel; slightly acid coarse roots; many very fine irregular pores; 20 percent (pH 6.4); abrupt smooth boundary. gravel-sized pumice; moderately acid (pH 5.6); abrupt A2-1 to 6 inches; dark brown (7.5YR 3/4) loam, brown wavy boundary. (7.5YR 5/4) dry; weak very fine and fine subangular 2ABb-25 to 33 inches; dark reddish brown (5YR 3/3) loam, blocky structure; soft, very friable, nonsticky and brown (7.5YR 5/4) dry; weak fine and medium nonplastic; few very fine roots; common very fine and subangular blocky structure; slightly hard, friable, fine irregular and few tubular and vesicular pores; 5 nonsticky and nonplastic; common roots; common very percent gravel; slightly acid (pH 6.5); abrupt wavy fine tubular pores; strongly acid (pH 5.2); clear wavy boundary. boundary. 2R-6 inches; andesite. 2Bwb-33 to 60 inches; dark reddish brown (5YR 3/3) cobbly loam, brown (5YR 5/4) dry; moderate fine and medium The depth to bedrock is 4 to 10 inches. The soils are subangular blocky structure; hard, firm, slightly sticky saturated to the surface for at least 1 month in most years. and slightly plastic; few roots; common very fine tubular The particle-size control section contains 50 to 85 percent pores; 5 percent gravel and 20 percent cobbles; rock fragments and 12 to 25 percent clay. moderately acid (pH 5.6). The A horizon has hue of 10YR or 7.5YR; value of 3 The depth to bedrock is 60 inches or more. The bulk density of the ash mantle is 0.75 to 0.90 gram per cubic centimeter. The thickness of the ash mantle and depth to C2-48 to 54 inches; light yellowish brown (2.5Y 6/4) coarse the buried soil are 20 to 40 inches. sandy loam, very pale brown (10YR 8/3) dry; massive; The A horizon has hue of 7.5YR or 10YR, value of 4 or 5 hard, friable, nonsticky and nonplastic; few very fine dry, and chroma of 2 to 4 moist and dry. The Bw horizon irregular pores; moderately acid (pH 5.8); gradual wavy has hue of 7.5YR or 10YR, value of 5 or 6 dry, and chroma boundary. of 4 to 6 moist and dry. It is sandy loam or gravelly sandy Cr-54 inches; weathered granodiorite. loam. The 2AB horizon, if it occurs, has hue of 7.5YR or 5YR, value of 4 or 5 dry, and chroma of 3 or 4 moist and The depth to bedrock is 40 to 60 inches. The dry. It is loam that contains 10 to 20 percent clay and 0 to particle-size control section contains 15 to 35 percent 15 percent rock fragments. The 2Bw horizon has hue of rock fragments and 5 to 15 percent clay. 7.5YR, 5YR, or 2.5YR; value of 4 or 5 dry; and chroma of 3 The A horizon has value of 3 or 4 moist, 4 to 6 dry, and or 4 moist, 3 to 6 dry. It is loam or clay loam in the fine-earth chroma of 2 to 4 moist and dry. The Bw horizon has hue of fraction and contains 25 to 35 percent clay and 5 to 35 10YR or 2.5Y; value of 4 or 5 moist, 5 or 6 dry; and chroma percent rock fragments. of 3 or 4 moist and dry. It is cobbly or gravelly coarse sandy loam. The C horizon has hue of 10YR or 2.5Y; value of 4 to Rogue Series 6 moist, 5 to 8 dry; and chroma of 2 to 4 moist and dry. It is coarse sandy loam, gravelly loamy coarse sand, or gravelly The Rogue series consists of deep, somewhat coarse sandy loam. excessively drained soils on hillslopes. These soils formed in colluvium derived from granitic rock. Slopes are 12 to 80 Royst Series percent. The mean annual precipitation is about 50 inches, and the mean annual temperature is about 43 degrees F. The Royst series consists of moderately deep, well Typical pedon of Rogue cobbly coarse sandy loam, 35 drained soils on plateaus and hillslopes. These soils formed to 75 percent south slopes; about 1,620 feet east and 40 in colluvium and residuum derived igneous rock and feet south of the northwest corner of sec. 18, T. 40 S., R. 2 containing small amounts of volcanic ash. Slopes are 1 to E. 35 percent. The mean annual precipitation is about 20 inches, and the mean annual temperature is about 44 A-0 to 6 inches; very dark grayish brown (10YR 3/2) cobbly degrees F. coarse sandy loam, brown (10YR 5/3) dry; weak fine Typical pedon of Royst gravelly loam, in an area of granular structure; loose, very friable, nonsticky and Bly-Royst complex, 1 to 12 percent slopes, about 3 miles nonplastic; many fine and very fine roots; few fine south of Round Lake; about 1,825 feet west and 2,025 irregular pores; 15 percent gravel and 15 percent feet north of the southeast corner of sec. 25, T. 39 S., R. 7 cobbles; neutral (pH 6.8); abrupt smooth boundary. E. Bw1-6 to 17 inches; brown (10YR 4/3) cobbly coarse sandy loam, pale brown (10YR 6/3) dry; weak medium Oi-1 inch to 0; needles and twigs. subangular blocky structure; soft, very friable, nonsticky A-0 to 4 inches; dark reddish brown (5YR 2.5/2) gravelly and nonplastic; many fine and medium roots; many very loam, reddish brown (5YR 4/3) dry; moderate very fine fine irregular pores; 10 percent gravel and 20 percent granular structure; soft, very friable, nonsticky and cobbles; neutral (pH 6.7); clear smooth boundary. nonplastic; common very fine, fine, and medium and Bw2-17 to 34 inches; yellowish brown (10YR 5/4) cobbly few coarse roots; many very fine pores; 15 percent coarse sandy loam, pale brown (10YR 6/3) dry; gravel and 5 percent cobbles; strongly acid (pH 5.4); massive; slightly hard, friable, nonsticky and nonplastic; abrupt smooth boundary. many fine and medium and few coarse roots; many very AB-4 to 11 inches; dark reddish brown (5YR 3/2) gravelly fine irregular pores; 10 percent gravel and 20 percent loam, brown (7.5YR 4/4) dry; moderate very fine cobbles; slightly acid (pH 6.4); clear wavy boundary. subangular blocky structure; slightly hard, friable, C1-34 to 48 inches; light olive brown (2.5Y 5/4) coarse slightly sticky and slightly plastic; common very fine, sandy loam, pale yellow (10YR 7/3) dry; massive; hard, fine, and medium and few coarse roots; common very friable, nonsticky and nonplastic; few medium and fine tubular pores; 15 percent gravel and 5 percent coarse roots; many very fine irregular pores; moderately cobbles; moderately acid (pH 5.8); abrupt wavy acid (pH 6.0); clear wavy boundary. boundary. Bt-11 to 21 inches; dark reddish brown (5YR 3/3) very cobbly clay loam, brown (7.5YR 4/4) dry; moderate very fine and fine subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; few very fine and fine roots; common very many fine roots; many very fine tubular pores; few faint fine tubular pores; few faint clay films on faces of red (2.5YR 4/6) clay films in pores; 10 percent gravel; peds; 25 percent gravel and 30 percent cobbles; common black concretions 2 to 4 millimeters in moderately acid (pH 5.8); clear wavy boundary. diameter; moderately acid (pH 5.8); clear wavy 2Cr-21 to 23 inches; decomposed andesite. boundary. 2R-23 inches; andesite. Bt1-17 to 26 inches; yellowish red (5YR 4/6) loam, yellowish red (5YR 5/6) dry; moderate fine subangular blocky The depth to bedrock is 20 to 40 inches. The structure; very hard, firm, sticky and plastic; common particle-size control section contains 27 to 35 percent fine roots; many very fine tubular pores; common clay and 35 to 60 percent rock fragments. The mollic distinct red (2.5YR 4/6) clay films on faces of peds; epipedon is 20 to 30 inches thick. common black concretions 2 to 4 millimeters in The A horizon has hue of 10YR, 7.5YR, or 5YR; value diameter; few black stains; 10 percent partially of 2 or 3 moist, 4 or 5 dry; and chroma of 2 or 3 moist, 3 weathered gravel; moderately acid (pH 5.8); gradual or 4 dry. The Bt horizon has hue of 10YR, 7.5YR, or 5YR; wavy boundary. value of 3 or 4 moist, 4 to 6 dry; and chroma of 2 to 4 Bt2-26 to 46 inches; yellowish red (5YR 4/6) loam, yellowish moist and dry. It is very gravelly or very cobbly clay loam. red (5YR 5/6) dry; moderate fine subangular blocky The Royst soils in this survey area are taxadjuncts to the structure; very hard, firm, sticky and plastic; few fine series because they have 27 to 35 percent clay in the roots; many very fine tubular pores; common distinct particle-size control section rather than 35 to 45 percent. red (2.5YR 4/6) clay films on faces of peds; common This difference, however, does not significantly affect the black concretions 2 to 4 millimeters in diameter; few use and management of the soils. black stains; 5 percent partially weathered gravel; moderately acid (pH 6.0); gradual wavy boundary. Ruch Series Bt3-46 to 70 inches; yellowish red (5YR 4/6) loam, yellowish red (5YR 5/6) dry; moderate medium subangular blocky The Ruch series consists of very deep, well drained structure; very hard, firm, sticky and plastic; few fine soils on foot slopes and alluvial fans. These soils formed roots; many very fine tubular pores; common distinct in mixed alluvium derived from altered sedimentary and red (2.5YR 4/6) clay films on faces of peds; common volcanic rock. Slopes are 2 to 20 percent. The mean black concretions 2 to 4 millimeters in diameter; 10 annual precipitation is about 30 inches, and the mean percent partially weathered gravel; slightly acid (pH annual temperature is about 52 degrees F. 6.1). Typical pedon of Ruch gravelly silt loam, 7 to 20 percent slopes, about 2 miles north of Ruch; about 520 feet west The depth to bedrock is 60 inches or more. The and 540 feet south of the northeast corner of sec. 15, T. 38 particle-size control section contains 25 to 35 percent S., R. 3 W. clay and 5 to 20 percent rock fragments. The A horizon has hue of 7.5YR or 10YR; value of 3 or 4 A1-0 to 2 inches; dark brown (7.5YR 3/3) gravelly silt loam, moist, 4 to 6 dry; and chroma of 2 to 4 moist and dry. It is brown (10YR 5/3) dry; moderate very fine granular silt loam or gravelly silt loam. The Bt horizon has hue of structure; slightly hard, friable, slightly sticky and slightly 5YR or 7.5YR; value of 3 or 4 moist, 5 or 6 dry; and chroma plastic; many very fine and fine roots; many fine of 4 to 6 moist and dry. It is loam, clay loam, gravelly loam, irregular pores; 20 percent gravel; slightly acid (pH 6.3); or gravelly clay loam. abrupt smooth boundary. A2-2 to 7 inches; dark brown (7.5YR 4/4) gravelly silt loam, Rustlerpeak Series light yellowish brown (10YR 6/4) dry; weak medium subangular blocky structure parting to moderate very The Rustlerpeak series consists of moderately deep, well fine granular; hard, friable, slightly sticky and slightly drained soils on plateaus and hillslopes. These soils formed plastic; many fine roots; many very fine tubular and in colluvium derived from igneous rock and volcanic ash. irregular pores; 20 percent gravel; slightly acid (pH 6.1); Slopes are 3 to 70 percent. The mean annual precipitation clear smooth boundary. is about 45 inches, and the mean annual temperature is BAt-7 to 17 inches; reddish brown (5YR 4/4) loam, light about 43 degrees F. brown (7.5YR 6/4) dry; weak medium subangular Typical pedon of Rustlerpeak gravelly loam, 12 to 35 blocky structure parting to moderate fine subangular percent north slopes; about 2,150 feet west and 2,100 feet blocky; hard, firm, sticky and plastic; south of the northeast corner of sec. 29, T. 38 S., R. 3 E. Oi-1 inch to 0; needles, leaves, and twigs. soft, friable, slightly sticky and slightly plastic; many A1-0 to 6 inches; dark reddish brown (5YR 2.5/2) gravelly very fine roots; many very fine vesicular and tubular loam, dark reddish brown (5YR 3/2) dry; strong very pores; 10 percent gravel; moderately acid (pH 5.7); fine and fine granular structure; soft, very friable, abrupt smooth boundary. nonsticky and nonplastic; common very fine, fine, and AB-4 to 17 inches; dark brown (7.5YR 3/4) loam, brown medium roots; common very fine and fine irregular (7.5YR 5/4) dry; dark brown (7.5YR 3/2) coatings; weak pores; 10 percent gravel and 5 percent cobbles; slightly medium subangular blocky structure parting to acid (pH 6.4); abrupt smooth boundary. moderate very fine granular; soft, friable, slightly sticky A2-6 to 12 inches; dark reddish brown (5YR 3/2) gravelly and slightly plastic; common very fine roots; many very loam, reddish brown (5YR 4/3) dry; moderate fine and fine vesicular and tubular pores; 10 percent gravel; medium granular structure; soft, very friable, slightly moderately acid (pH 5.6); clear smooth boundary. sticky and slightly plastic; common very fine, fine, Bt-17 to 29 inches; reddish brown (5YR 4/4) clay loam, medium, and coarse roots; common very fine and fine reddish brown (5YR 5/4) dry; moderate medium irregular pores; 15 percent gravel and 5 percent subangular blocky structure; slightly hard, friable, sticky cobbles; slightly acid (pH 6.2); clear smooth boundary. and plastic; common fine and medium roots; common Bw-12 to 23 inches; dark reddish brown (5YR 3/3) very fine and many very fine tubular pores; few distinct and cobbly clay loam, reddish brown (5YR 4/3) dry; common faint dark reddish brown (5YR 3/4) clay films moderate very fine and fine subangular blocky on faces of peds; 5 percent gravel; moderately acid (pH structure; slightly hard, friable, slightly sticky and slightly 5.9); abrupt smooth boundary. plastic; common very fine, fine, medium, and coarse 2C-29 to 60 inches; olive brown (2.5Y 4/4) clay, light roots; few very fine and fine irregular pores; 25 percent yellowish brown (2.5Y 6/4) dry; massive; extremely gravel and 15 percent cobbles; slightly acid (pH 6.2); hard, extremely firm, very sticky and very plastic; few clear wavy boundary. coarse roots; few fine tubular pores; common fine to Cr-23 inches; decomposed andesite. coarse slickensides and few intersecting slickensides; slightly acid (pH 6.1). The depth to bedrock is 20 to 40 inches. The particle-size control section contains 35 to 70 percent The depth to bedrock is 60 inches or more. The upper rock fragments and 20 to 35 percent clay. The umbric part of the particle-size control section contains 27 to 35 epipedon is 10 to 20 inches thick. percent clay, and the lower part contains 55 to 70 percent The A horizon has hue of 5YR or 7.5YR; value of 2 or 3 clay. Depth to the clayey substratum is 12 to 36 inches. moist, 3 to 5 dry; and chroma of 2 or 3 moist, 2 to 4 dry. It The A horizon has hue of 10YR or 7.5YR; value of 3 or 4 has a bulk density of 0.85 to 0.95 gram per cubic moist, 4 or 5 dry; and chroma of 2 to 4 moist, 3 or 4 dry. centimeter. The Bw horizon has hue of 5YR or 7.5YR; value The Bt horizon has hue of 10YR, 7.5YR, or 5YR; value of 3 of 3 or 4 moist, 4 or 5 dry; and chroma of 2 or 3 moist, 2 to or 4 moist, 4 or 5 dry; and chroma of 3 or 4 moist and dry. It 4 dry. It is very cobbly clay loam, very cobbly loam, very is clay loam or gravelly clay loam. A stone line is at the gravelly loam, or extremely gravelly clay loam. base of the solum in some pedons. The 2C horizon has hue of 2.5Y or 5Y; value of 4 or 5 moist, 6 or 7 dry; and Selmac Series chroma of 2 to 4 moist and dry.

The Selmac series consists of very deep, moderately Sevenoaks Series well drained soils in basins. These soils formed in loamy and clayey alluvium. Slopes are 2 to 20 percent. The mean The Sevenoaks series consists of very deep, somewhat annual precipitation is about 30 inches, and the mean excessively drained soils on stream terraces. These soils annual temperature is about 52 degrees F. formed in alluvium derived from pumice and igneous rock. Typical pedon of Selmac loam, 7 to 20 percent slopes, Slopes are 0 to 3 percent. The mean annual precipitation is about 6 miles southeast of the city of Rogue River; about about 22 inches, and the mean annual temperature is about 1,850 feet north and 975 feet east of the southwest 53 degrees F. corner of sec. 13, T. 37 S., R. 4 W. Typical pedon of Sevenoaks loamy sand, 0 to 3 percent slopes, about 1 mile south of Upper Table A-0 to 4 inches; dark brown (7.5YR 3/2) loam, brown (7.5YR 5/2) dry; weak medium subangular blocky structure parting to moderate very fine granular; Rock; about 1,800 feet west and 220 feet south of the 725 feet south and 1,850 feet east of the northwest northeast corner of sec. 15, T. 36 S., R. 2 W. corner of sec. 31, T. 39 S., R. 2 W.

Ap1-0 to 7 inches; very dark brown (10YR 2/2) loamy sand, A-0 to 4 inches; dark brown (7.5YR 3/2) loam, brown (10YR dark grayish brown (10YR 4/2) dry; weak medium and 5/3) dry; moderate fine granular structure; soft, friable, coarse subangular blocky structure; slightly hard, slightly sticky and slightly plastic; common very fine and friable, nonsticky and nonplastic; very few fine roots; fine roots; common very fine irregular pores; moderately many fine irregular pores; 10 percent fine pumice acid (pH 6.0); clear wavy boundary. gravel; moderately acid (pH 6.0); abrupt smooth BA-4 to 10 inches; reddish brown (5YR 4/4) loam, light boundary. brown (7.5YR 6/4) dry; moderate fine subangular blocky Ap2-7 to 14 inches; very dark brown (10YR 2/2) loamy structure; slightly hard, friable, sticky and slightly plastic; sand, dark grayish brown (10YR 4/2) dry; massive; few medium and common very fine and fine roots; few slightly hard, friable, nonsticky and nonplastic; very few very fine tubular pores; moderately acid (pH 6.0); clear fine roots; many fine irregular pores; 10 percent fine wavy boundary. pumice gravel; moderately acid (pH 6.0); clear smooth Bt1-10 to 19 inches; reddish brown (5YR 4/4) clay loam, boundary. reddish brown (5YR 5/4) dry; moderate fine and AC-14 to 22 inches; dark brown (10YR 3/3) gravelly sand, medium subangular blocky structure; hard, firm, sticky brown (10YR 5/3) dry; single grain; loose, very friable, and plastic; common very fine and fine and few medium nonsticky and nonplastic; very few fine roots; many fine roots; few very fine tubular pores; few distinct clay films irregular pores; 15 percent pumice gravel; slightly acid on faces of peds and in pores; moderately acid (pH 6.0); (pH 6.4); gradual wavy boundary. clear wavy boundary. C1-22 to 54 inches; olive brown (2.5Y 3/3) gravelly coarse Bt2-19 to 40 inches; reddish brown (5YR 4/4) clay loam, sand, light olive brown (2.5Y 5/3) dry; single grain; reddish brown (5YR 5/4) dry; strong medium and coarse loose, nonsticky and nonplastic; very few fine roots; subangular blocky structure; very hard, firm, sticky and many fine irregular pores; 20 percent fine pumice plastic; common very fine and fine and few medium gravel; slightly acid (pH 6.4); clear wavy boundary. roots; common fine tubular pores; common distinct clay C2-54 to 60 inches; dark grayish brown (2.5Y 4/2) gravelly films on faces of peds and in pores; 5 percent gravel; sand, grayish brown (2.5Y 5/2) dry; single grain; loose, slightly acid (pH 6.3); gradual wavy boundary. nonsticky and nonplastic; many fine irregular pores; 20 Bt3-40 to 56 inches; reddish brown (5YR 4/4) sandy clay percent fine pumice gravel; slightly acid (pH 6.4). loam, reddish brown (5YR 5/4) dry; moderate medium and coarse subangular blocky structure; very hard, firm, The depth to bedrock is 60 inches or more. The sticky and plastic; few fine roots; common fine tubular particle-size control section is sand or loamy sand and pores; common distinct clay films on faces of peds and contains 15 to 30 percent gravel and less than 5 percent in pores; 5 percent gravel; slightly acid (pH 6.3); diffuse clay. wavy boundary. The A horizon has value of 2 or 3 moist, 4 or 5 dry, and Cr-56 inches; decomposed granitic rock. chroma of 2 or 3 moist and dry. The AC and C horizons have hue of 10YR or 2.5Y; value of 3 or 4 moist, 5 or 6 The depth to bedrock is 40 to 60 inches. The dry; and chroma of 2 or 3 moist and dry. They are gravelly particle-size control section contains 20 to 35 percent sand, gravelly coarse sand, or gravelly loamy sand. clay. The A horizon has hue of 10YR or 7.5YR; value of 3 or 4 Shefflein Series moist, 5 or 6 dry; and chroma of 2 to 4 moist and dry. The Bt horizon has hue of 10YR, 5YR, or 7.5YR; value of 3 to 5 The Shefflein series consists of deep, well drained soils moist, 5 to 7 dry; and chroma of 3 to 6 moist and dry. It is on alluvial fans and hillslopes. These soils formed in clay loam, loam, or sandy clay loam. alluvium, colluvium, and residuum derived from granitic rock. Slopes are 2 to 35 percent. The mean annual Shippa Series precipitation is about 32 inches, and the mean annual temperature is about 50 degrees F. The Shippa series consists of shallow, well drained soils Typical pedon of Shefflein loam, 20 to 35 percent on hillslopes. These soils formed in colluvium derived from south slopes, about 8 miles southeast of Ruch; about igneous rock. Slopes are 35 to 70 percent. The mean annual precipitation is about 45 inches, and the brown (7.5YR 5/4) dry; weak fine and medium mean annual temperature is about 48 degrees F. subangular blocky structure; slightly hard, friable, Typical pedon of Shippa extremely gravelly loam, in an slightly sticky and slightly plastic; common very fine area of Straight-Shippa extremely gravelly loams, 35 to 60 roots; many very fine tubular pores; 10 percent gravel; percent south slopes, about 9 miles north of Trail; about neutral (pH 6.6); gradual smooth boundary. 1,550 feet west and 1,050 feet south of the northeast Bw2-15 to 24 inches; dark brown (7.5YR 3/4) loam, brown corner of sec. 23, T. 32 S., R. 1 W. (7.5YR 5/4) dry; moderate fine and medium subangular blocky structure; slightly hard, friable, slightly sticky and A-0 to 4 inches; dark brown (7.5YR 3/2) extremely gravelly slightly plastic; common very fine roots; many fine and loam, pinkish gray (7.5YR 6/2) dry; moderate fine medium tubular pores; 10 percent gravel; slightly acid granular structure; soft, very friable, nonsticky and (pH 6.5); abrupt wavy boundary. nonplastic; many very fine, fine, medium, and coarse 2R-24 inches; andesite. roots; many very fine irregular pores; 50 percent gravel and 15 percent cobbles; slightly acid (pH 6.4); clear The depth to bedrock is 20 to 40 inches. The smooth boundary. particle-size control section contains 18 to 30 percent Bw-4 to 16 inches; brown (7.5YR 4/4) extremely cobbly clay. loam, light brown (7.5YR 6/4) dry; moderate fine and The A horizon has hue of 10YR or 7.5YR; value of 3 medium subangular blocky structure; hard, friable, moist, 4 or 5 dry; and chroma of 3 moist, 3 or 4 dry. The Bw slightly sticky and slightly plastic; many very fine, fine, horizon has hue of 10YR or 7.5YR; value of 3 or 4 moist, 5 medium, and coarse roots; many very fine tubular or 6 dry; and chroma of 4 moist, 3 or 4 dry. It is clay loam, pores; 20 percent gravel and 50 percent cobbles; loam, or silt loam. moderately acid (pH 6.0); abrupt wavy boundary. R-16 inches; fractured andesite; roots and soil material in Sibannac Series some cracks in the upper few inches. The Sibannac series consists of very deep, poorly The depth to bedrock is 12 to 20 inches. The drained soils in basins. These soils formed in mixed particle-size control section contains 40 to 75 percent alluvium derived from igneous rock. Slopes are 0 to 7 rock fragments and 18 to 27 percent clay. percent. The mean annual precipitation is about 35 The A horizon has value of 3 or 4 moist, 6 or 7 dry, and inches, and the mean annual temperature is about 43 chroma of 2 or 3 moist and dry. The Bw horizon has value degrees F. of 6 or 7 dry and chroma of 3 or 4 moist and dry. It is very Typical pedon of Sibannac silt loam, 0 to 7 percent cobbly or extremely cobbly loam. slopes; about 910 feet east and 2,525 feet north of the southwest corner of sec. 10, T. 38 S., R. 3 E. Shoat Series A1-0 to 6 inches; black (10YR 2/1) silt loam, dark gray The Shoat series consists of moderately deep, well (10YR 4/1) dry; weak very fine granular structure; soft, drained soils on plateaus. These soils are on mounds in friable, slightly sticky and slightly plastic; many very fine areas of patterned ground. They formed in loess over roots; many very fine irregular pores; moderately acid igneous rock. Slopes are 0 to 5 percent. The mean annual (pH 5.8); abrupt smooth boundary. precipitation is about 22 inches, and the mean annual A2-6 to 11 inches; black (10YR 2/1) silty clay loam, very temperature is about 49 degrees F. dark gray (10YR 3/1) dry; moderate fine subangular Typical pedon of Shoat loam, in an area of blocky and granular structure; hard, friable, sticky and Randcore-Shoat complex, 0 to 5 percent slopes; about plastic; few fine and many very fine roots; many very 750 feet north and 200 feet east of the southwest corner of fine irregular pores; moderately acid (pH 6.0); clear sec. 11, T. 41 S., R. 4 E. smooth boundary. Bw1-11 to 27 inches; very dark gray (10YR 3/1) clay loam, A-0 to 4 inches; dark brown (7.5YR 3/2) loam, brown dark gray (10YR 4/1) dry; moderate fine and medium (7.5YR 4/4) dry; weak fine subangular blocky structure subangular blocky structure; hard, friable, sticky and parting to weak very fine granular; slightly hard, friable, plastic; many very fine roots; many very fine irregular nonsticky and nonplastic; common very fine roots; pores; slightly acid (pH 6.2); gradual smooth boundary. many very fine irregular pores; 10 percent gravel; 2Bw2-27 to 32 inches; very dark grayish brown (10YR 3/2) neutral (pH 6.7); clear smooth boundary. clay loam, dark grayish brown (10YR 4/2) dry; few faint Bw1-4 to 15 inches; dark brown (7.5YR 3/4) loam, dark brown (7.5YR 4/4) mottles; moderate medium subangular blocky structure; hard, firm, very slightly sticky and slightly plastic; common very fine, sticky and very plastic; common very fine roots; few fine, medium, and coarse roots; common irregular fine tubular and many very fine irregular pores; slightly pores; 10 percent gravel; moderately acid (pH 5.6); acid (pH 6.3); gradual smooth boundary. gradual wavy boundary. 2C1-32 to 42 inches; very dark grayish brown (10YR 3/2) C-17 to 35 inches; grayish brown (2.5Y 5/3) sandy loam, clay loam, dark grayish brown (10YR 4/2) dry; common light gray (2.5Y 7/3) dry; massive; hard, firm, slightly fine distinct dark brown (7.5YR 4/4) and strong brown sticky and slightly plastic; few very fine and fine roots; (7.5YR 4/6) mottles; massive; slightly hard, firm, sticky common irregular pores; 10 percent gravel; strongly and plastic; few very fine roots; common very fine acid (pH 5.4); gradual irregular boundary. tubular pores; slightly acid (pH 6.4); clear smooth Cr-35 inches; decomposed granodiorite. boundary. 3C2-42 to 60 inches; black (10YR 2/1) clay loam, dark gray The depth to bedrock is 20 to 40 inches. The (10YR 4/1) dry; massive; slightly hard, firm, sticky and particle-size control section contains 8 to 12 percent plastic; few very fine roots; common very fine tubular clay, 10 to 35 percent rock fragments, and 15 to 50 pores; slightly acid (pH 6.4). percent coarse sand and very coarse sand. The A horizon has value of 3 or 4 moist, 4 to 6 dry, and The depth to bedrock is 60 inches or more. The soils are chroma of 2 or 3 moist and dry. The Bw horizon has hue of saturated to the surface for at least 1 month in most years. 10YR, 7.5YR, or 2.5Y; value of 4 or 5 moist, 5 to 7 dry; and The particle-size control section contains 27 to 35 percent chroma of 2 to 4 moist and dry. It is gravelly coarse sandy clay. The mollic epipedon is 24 to 40 inches thick. The soils loam, sandy loam, or gravelly sandy loam. The C horizon are characterized by an irregular decrease in content of has hue of 10YR or 2.5Y; value of 5 or 6 moist, 7 or 8 dry; organic matter to a depth of 50 inches. and chroma of 2 to 4 moist and dry. It is sandy loam or The A horizon has value of 2 or 3 moist, 3 or 4 dry, and coarse sandy loam. Some pedons have loamy coarse sand chroma of 1 or 2 moist and dry. The 2Bw horizon has in the lower part. chroma of 1 or 2 moist and dry. It is clay loam or silty clay loam. The 2C and 3C horizons have value of 2 or 3 moist Skookum Series and chroma of 1 or 2 moist and dry. They are clay loam or silty clay loam. The Skookum series consists of moderately deep, well drained soils on plateaus and hillslopes. These soils Siskiyou Series formed in colluvium and residuum derived from igneous rock. Slopes are 1 to 70 percent. The mean annual The Siskiyou series consists of moderately deep, precipitation is about 25 inches, and the mean annual somewhat excessively drained soils on hillslopes. These temperature is about 48 degrees F. soils formed in colluvium derived from granitic rock. Typical pedon of Skookum very cobbly loam, in an Slopes are 35 to 60 percent. The mean annual area of Skookum-Rock outcrop-Rubble land complex, 35 precipitation is about 45 inches, and the mean annual to 70 percent slopes, about 6 miles south of Pinehurst; temperature is about 49 degrees F. about 1,650 feet west and 40 feet north of the southeast Typical pedon of Siskiyou gravelly sandy loam, 35 to 60 corner of sec. 4, T. 41 S., R. 4 E. percent north slopes; about 100 feet east and 550 feet south of the northwest corner of sec. 24, T. 34 S., R. 4 W. A-0 to 3 inches; very dark brown (10YR 2/2) very cobbly loam, dark grayish brown (10YR 4/2) dry; weak very Oi-1 inch to 0: needles and twigs. fine and fine granular structure; soft, very friable, slightly A-0 to 9 inches; dark brown (10YR 3/3) gravelly sandy sticky and slightly plastic; many very fine roots; many loam, pale brown (10YR 6/3) dry; strong fine and very fine irregular pores; 15 percent gravel, 30 percent medium granular structure; slightly hard, very friable, cobbles, and 5 percent stones; neutral (pH 7.2); abrupt slightly sticky and slightly plastic; many very fine and wavy boundary. fine and common medium roots; many irregular pores; BAt-3 to 8 inches; very dark grayish brown (10YR 3/2) very 15 percent gravel; moderately acid (pH 5.6); abrupt cobbly loam, dark grayish brown (10YR 4/3) dry; smooth boundary. moderate fine and medium subangular blocky structure; Bw-9 to 17 inches; olive brown (2.5Y 4/4) sandy loam, light hard, firm, slightly sticky and slightly plastic; few very gray (2.5Y 7/3) dry; moderate very fine and fine fine roots; few very fine tubular pores; few faint clay subangular blocky structure; hard, friable, films on faces of peds and in pores; 10 percent gravel and 25 percent cobbles; coarse roots; many very fine irregular pores; 15 neutral (pH 7.0); clear wavy boundary. percent gravel; strongly acid (pH 5.4); clear smooth Bt1-8 to 16 inches; very dark grayish brown (10YR 3/2) very boundary. cobbly clay loam, dark grayish brown (10YR 4/2) dry; A2-5 to 12 inches; very dark grayish brown (10YR 3/2) moderate fine subangular blocky structure; very hard, gravelly loam, brown (10YR 4/3) dry; moderate very firm, sticky and plastic; few very fine roots; few very fine fine and fine subangular blocky structure; soft, friable, tubular pores; few faint clay films on faces of peds and nonsticky and nonplastic; common very fine, fine, in pores; 10 percent gravel and 45 percent cobbles; medium, and coarse roots; many very fine tubular neutral (pH 6.7); gradual wavy boundary. pores; 20 percent gravel and 5 percent cobbles; Bt2-16 to 22 inches; dark brown (7.5YR 3/3) very cobbly moderately acid (pH 5.6); clear wavy boundary. clay, brown (7.5YR 4/2) dry; moderate fine and medium Bw1-12 to 22 inches; dark grayish brown (2.5Y 4/2) very subangular blocky structure; very hard, very firm, very gravelly loam, light olive brown (2.5Y 5/4) dry; sticky and very plastic; few medium roots; few very fine moderate very fine subangular blocky structure; slightly tubular pores; few faint clay films on faces of peds and hard, friable, slightly sticky and nonplastic; common in pores; 10 percent gravel and 45 percent cobbles; very fine, fine, and medium roots; common very fine neutral (pH 6.7); gradual wavy boundary. tubular pores; 30 percent gravel and 10 percent Bt3-22 to 28 inches; dark brown (7.5YR 3/4) extremely cobbles; moderately acid (pH 5.6); clear wavy cobbly clay, brown (7.5YR 4/2) dry; moderate fine boundary. angular blocky structure; very hard, very firm, very Bw2-22 to 39 inches; olive (5Y 4/3) very cobbly loam, olive sticky and very plastic; few fine roots; few very fine (5Y 5/3) dry; weak very fine subangular blocky tubular pores; few faint clay films on faces of peds structure; slightly hard, friable, slightly sticky and and in pores; 40 percent cobbles and 30 percent nonplastic; few very fine, fine, and medium roots; stones; neutral (pH 6.7); abrupt irregular boundary. common very fine tubular pores; 35 percent gravel and R-28 inches; fractured andesite.' 20 percent cobbles; moderately acid (pH 5.6); clear wavy boundary.

R-39 inches; fractured schist. The depth to bedroc k is 20 to 40 inches. The particle-size control section contains 35 to 50 percent The depth to bedrock is 20 to 40 inches. The clay and 40 to 80 percent rock fragments. The mollic particle-size control section contains 35 to 75 percent epipedon is 20 to 30 inches thick. rock fragments and 15 to 25 percent clay. The umbric The A horizon has value of 2 or 3 moist, 3 or 4 dry, epipedon is 10 to 20 inches thick. and chroma of 2 or 3 moist and dry. The Bt horizon has The A horizon has hue of 10YR, 2.5Y, or 5Y; value hue of 10YR or 7.5YR, value of 3 or 4 dry, and chroma of 2 or 3 moist, 3 to 5 dry; and chroma of 1 or 2 moist, of 2 to 4 moist, 2 to 3 dry. It is very cobbly clay loam, 2 or 3 dry. The Bw horizon has hue of 10YR, 2.5Y, or very cobbly clay, or extremely cobbly clay. 5Y; value of 3 or 4 moist, 5 or 6 dry; and chroma of 2 or 3 moist, 2 to 4 dry. It is very gravelly, very cobbly, or Snowbrier Series extremely cobbly loam. The Snowbrier series consists of moderately deep, well drained soils on hillslopes. These soils formed in colluvium Snowlin Series derived from altered volcanic rock. Slopes are 25 to 50 percent. The mean annual precipitation is about 50 inches, The Snowlin series consists of very deep, well drained and the mean annual temperature is about 43 degrees F. soils on plateaus and hillslopes. These soils formed in Typical pedon of Snowbrier gravelly loam, 25 to 50 colluvium derived from igneous rock and containing percent south slopes; about 700 feet north and 1,250 feet volcanic ash. Slopes are 3 to 35 percent. The mean east of the southwest corner of sec. 6, T. 33 S., R. 2 W. annual precipitation is about 45 inches, and the mean annual temperature is about 43 degrees F. Oi-1 inch to 0; needles, leaves, and twigs. Typical pedon of Snowlin gravelly loam, 3 to 12 A1-0 to 5 inches; very dark brown, (10YR 2/2) gravelly percent slopes, on Bald Mountain; about 1,650 feet loam, brown (10YR 4/3) dry; moderate fine granular west and 1,600 feet north of the southeast corner of structure; soft, friable, nonsticky and nonplastic; many sec. 14, T. 32 S., R. 2 E. very fine and common fine, medium, and Oi-2 inches to 0; needles and twigs. A-0 to 6 inches; dark reddish brown (5YR 2.5/2) gravelly loam, dark brown (7.5YR 3/2) dry; moderate slopes, near East Evans Creek; about 2,280 feet west and fine granular structure; soft, friable, nonsticky and 1,850 feet north of the southeast corner of sec. 27, T. 34 nonplastic; many very fine and fine and common S., R. 3 W. medium and coarse roots; many fine irregular pores; 15 percent gravel; moderately acid (pH 5.6); abrupt smooth boundary. Oi-1 inch to 0; leaves, needles, twigs, and grasses. AB-6 to 20 inches; dark reddish brown (5YR 3/2) gravelly A1-0 to 2 inches; dark brown (10YR 3/3) loam, brown (10YR loam, brown (7.5YR 5/2) dry; moderate very fine and 5/3) dry; strong very fine and fine granular structure; fine subangular blocky structure; soft, friable, slightly slightly hard, very friable, nonsticky and nonplastic; sticky and slightly plastic; common very fine, fine, and common very fine and fine roots; many fine and medium medium roots; many very fine and fine irregular pores; irregular pores; 10 percent gravel; slightly acid (pH 6.5); 15 percent gravel; moderately acid (pH 5.6); clear abrupt smooth boundary. smooth boundary. A2-2 to 6 inches; dark brown (10YR 3/3) loam, brown Bw1-20 to 34 inches; dark reddish brown (5YR 3/3) gravelly (7.5YR 5/3) dry; moderate medium and coarse granular clay loam, brown (7.5YR 5/3) dry; moderate very fine structure; slightly hard, very friable, nonsticky and and fine subangular blocky structure; soft, friable, nonplastic; common very fine and fine and few coarse slightly sticky and slightly plastic; common very fine, and medium roots; many very fine and fine irregular fine, medium, and coarse roots; common very fine and pores; 10 percent gravel; slightly acid (pH 6.3); abrupt fine pores; 20 percent gravel and 5 percent cobbles; smooth boundary. strongly acid (pH 5.4); abrupt wavy boundary. AB-6 to 13 inches; dark brown (7.5YR 3/4) loam, brown Bw2-34 to 60 inches; dark reddish brown (5YR 3/3) very (7.5YR 5/4) dry; moderate fine subangular blocky gravelly clay loam, brown (7.5YR 5/3) dry; moderate structure; slightly hard, friable, slightly sticky and slightly fine and medium subangular blocky structure; soft, plastic; common very fine, fine, medium, and coarse friable, slightly sticky and plastic; few very fine, fine, and roots; common fine irregular and very fine tubular pores; medium roots; common very fine pores; 35 percent 10 percent gravel; moderately acid (pH 5.9); clear gravel and 10 percent cobbles; strongly acid (pH 5.4). smooth boundary. Bt1-13 to 23 inches; dark brown (7.5YR 3/4) loam, brown The depth to bedrock is 60 inches or more. The (7.5YR 5/4) dry; moderate fine and medium subangular particle-size control section contains 27 to 35 percent blocky structure; hard, firm, sticky and plastic; common clay and 5 to 35 percent rock fragments. The umbric very fine, fine, medium, and coarse roots; few fine epipedon is 10 to 20 inches thick. irregular and common very fine and fine tubular pores; The A and AB horizons have hue of 10YR, 7.5YR, or few faint and distinct clay films in pores; 10 percent 5YR; value of 2 or 3 moist, 3 to 5 dry; and chroma of 1 or 2 gravel; moderately acid (pH 5.6); clear wavy boundary. moist, 2 to 4 dry. They have a bulk density of 0.85 to 0.95 Bt2-23 to 35 inches; brown (7.5YR 4/4) gravelly clay loam, gram per cubic centimeter. The Bw horizon has hue of strong brown (7.5YR 4/6) dry; strong medium 10YR, 7.5YR, or 5YR; value of 3 or 4 moist, 4 to 6 dry; and subangular blocky structure; hard, firm, sticky and chroma of 2 to 4 moist and dry. It is dominantly gravelly clay plastic; few very fine, fine, medium, and coarse roots; loam, cobbly clay loam, or clay loam. In some pedons, few fine and common medium tubular pores; common however, it is very gravelly in the lower part. faint and distinct clay films in pores; 15 percent gravel and 5 percent cobbles; moderately acid (pH 5.6); abrupt Speaker Series irregular boundary. Cr-35 inches; decomposed schist. The Speaker series consists of moderately deep, well drained soils on hillslopes. These soils formed in colluvium derived from altered sedimentary and volcanic rock. Slopes The depth to bedrock is 20 to 40 inches. The are 12 to 55 percent. The mean annual precipitation is about particle-size control section contains 25 to 35 percent 45 inches, and the mean annual temperature is about 49 clay and 0 to 30 percent rock fragments. degrees F. The A horizon has hue of 10YR or 7.5YR; value of 3 or 4 Typical pedon of Speaker loam, in an area of moist, 4 to 6 dry; and chroma of 2 to 6 moist and dry. The Josephine-Speaker complex, 12 to 35 percent south Bt horizon has hue of 7.5YR or 5YR; value of 4 or 5 moist, 4 to 7 dry; and chroma of 4 to 6 moist and dry. It is gravelly clay loam, clay loam, gravelly loam, or loam. Steinmetz Series to very gravelly sand and in most pedons is underlain by weathered granodiorite. The Steinmetz series consists of very deep, somewhat excessively drained soils on hillslopes. These soils Straight Series formed in colluvium derived from granitic rock. Slopes are 35 to 75 percent. The mean annual precipitation is about The Straight series consists of moderately deep, well 50 inches, and the mean annual temperature is about 48 drained soils on hillslopes. These soils formed in colluvium degrees F. derived from igneous rock. Slopes are 12 to 70 percent. Typical pedon of Steinmetz sandy loam, 35 to 75 percent The mean annual precipitation is about 45 inches, and the north slopes; about 2,300 feet east and 2,150 feet south of mean annual temperature is about 48 degrees F. the northwest corner of sec. 5, T. 33 S., R. 3 W. Typical pedon of Straight extremely gravelly loam, in an area of Straight-Shippa extremely gravelly loams, 35 to 60 Oi-1 inch to 0; needles and twigs. percent south slopes, about 3.5 miles northwest of Trail on A-0 to 4 inches; very dark grayish brown (10YR 3/2) sandy the West Fork of Trail Creek; about 2,050 feet west and loam, pale brown (10YR 6/3) dry; strong fine granular 1,575 feet north of the southeast corner of sec. 13, T. 33 S., structure; hard, very friable, nonsticky and slightly R. 2 W. plastic; many very fine, fine, and medium roots; many very fine irregular pores; 10 percent gravel and 3 Oi-1 1/2 inches to 0; twigs, needles, and leaves. percent cobbles; slightly acid (pH 6.4); clear smooth A-0 to 9 inches; dark reddish brown (5YR 2.5/2) extremely boundary. gravelly loam, dark brown (7.5YR 3/2) dry; strong very AB-4 to 13 inches; brown (10YR 4/3) sandy loam, light fine and fine granular structure; soft, very friable, yellowish brown (10YR 6/4) dry; moderate very fine and nonsticky and nonplastic; many very fine roots; many fine subangular blocky structure; hard, very friable, fine irregular pores; 75 percent gravel; moderately acid nonsticky and slightly plastic; common very fine, fine, (pH 6.0); abrupt smooth boundary. and medium and few coarse roots; many very fine BA-9 to 19 inches; dark brown (7.5YR 3/4) very gravelly tubular pores; 10 percent gravel and 3 percent cobbles; loam, pinkish gray (7.5YR 6/2) dry; strong medium and moderately acid (pH 5.8); gradual wavy boundary. fine granular structure; soft, very friable, nonsticky and Bw1-13 to 33 inc hes; dark yellowish brown (10YR 4/4) nonplastic; many very fine roots; many fine irregular sandy loam, light yellowish brown (10YR 6/4) dry; pores; 40 percent gravel and 10 percent cobbles; moderate very fine and fine subangular blocky structure; moderately acid (pH 5.8); clear smooth boundary. hard, very friable, nonsticky and slightly plastic; Bw1-19 to 30 inches; dark brown (7.5YR 4/4) very gravelly common very fine, fine, and medium and few coarse loam, light yellowish brown (10YR 6/4) dry; moderate roots; many very fine tubular pores; 10 percent gravel fine and medium subangular blocky structure; slightly and 3 percent cobbles; moderately acid (pH 6.0); hard, friable, slightly sticky and slightly plastic; common gradual wavy boundary. very fine, fine, and medium roots; many very fine and Bw2-33 to 60 inches; brown (7.5YR 4/4) sandy loam, very fine irregular pores; 35 percent gravel and 10 percent pale brown (10YR 7/4) dry; moderate very fine and fine cobbles; moderately acid (pH 5.8); clear wavy boundary. subangular blocky structure; hard, very friable, Bw2-30 to 35 inches; dark brown (7.5YR 4/4) very cobbly nonsticky and slightly plastic; few very fine, fine, clay loam, light yellowish brown (10YR 6/4) dry; medium, and coarse roots; common very fine tubular moderate fine and very fine subangular blocky structure; pores; 10 percent gravel and 3 percent cobbles; hard, friable, slightly sticky and plastic; common fine moderately acid (6.0). roots; many very fine and fine irregular pores; 30 percent gravel and 20 percent cobbles; moderately acid The depth to bedrock is 60 inches or more. The (pH 5.6); clear wavy boundary. particle-size. control section contains 10 to 18 percent Cr-35 inches; partially weathered, fractured andesite. clay and 0 to 35 percent rock fragments. The A horizon has hue of 10YR or 7.5YR; value of 2 to 4 The depth to bedrock is 20 to 40 inches. The moist, 4 to 6 dry; and chroma of 2 to 4 moist and dry. The particle-size control section contains 35 to 60 percent Bw horizon has hue of 10YR or 7.5YR; value of 4 or 5 rock fragments and 18 to 30 percent clay. moist, 6 to 8 dry; and chroma of 4 to 6 moist and dry. It is The A horizon has hue of 7.5YR or 5YR; value of 2 to 3 sandy loam or gravelly sandy loam. Some pedons have a moist, 3 to 6 dry; and chroma of 2 or 3 moist and BC or C horizon, which is sandy loam dry. The Bw horizon has hue of 7.5YR or 5YR moist, 5YR, Bt3-29 to 38 inches; brown (10YR 4/3) very cobbly clay, 7.5YR, or 10YR dry; value of 3 or 4 moist; and chroma of 2 dark yellowish brown (10YR 4/4) dry; weak medium and to 4 moist and dry. It is very gravelly loam, very gravelly coarse angular blocky structure; very hard, firm, very clay loam, or very cobbly clay loam. sticky and very plastic; few very fine, fine, and medium roots; few very fine tubular pores; many prominent clay Tablerock Series films on faces of peds and in pores; few slickensides; 10 percent gravel and 40 percent cobbles and stones; The Tablerock series consists of very deep, moderately moderately acid (pH 5.6); clear wavy boundary. well drained soils on hillslopes and alluvial fans. These Bt4-38 to 49 inches; dark yellowish brown (10YR 4/4) soils formed in colluvium derived from igneous and gravelly clay loam, pale brown (10YR 6/3) dry; weak fine sedimentary rock. Slopes are 20 to 50 percent. The mean and medium subangular blocky structure; slightly hard, annual precipitation is about 24 inches, and the mean very firm,' sticky and very plastic; few fine and medium annual temperature is about 49 degrees F. roots; few very fine tubular pores; many faint clay films Typical pedon of Tablerock gravelly loam, in an area of on faces of peds and common distinct clay films on Carney-Table rock complex, 20 to 35 percent slopes; about faces of peds and in pores; common small black stains; 2,400 feet west and 200 feet north of the southeast corner 20 percent gravel and 10 percent cobbles; strongly acid of sec. 4, T. 36 S., R. 2 W. (pH 5.5); gradual wavy boundary. BCt-49 to 65 inches; dark yellowish brown (10YR 4/4) Oi-1 1/2 inches to 0; leaves, twigs, and moss. gravelly loam, very pale brown (10YR 7/3) dry; massive; A-0 to 3 inches; very dark brown (10YR 2/2) gravelly loam, slightly hard, very firm, slightly sticky and plastic; few brown (10YR 5/3) dry; strong very fine, fine, and fine and medium roots; many distinct and faint clay films medium granular and moderate very fine and fine on faces of peds; common small black stains; 20 subangular blocky structure; slightly hard, firm, sticky percent gravel and 10 percent cobbles; moderately acid and plastic; many very fine roots; common fine and (pH 5.7); gradual wavy boundary. medium irregular pores; 15 percent gravel; slightly acid 2Cr-65 inches; weathered sandstone. (pH 6.1); abrupt smooth boundary. BAt-3 to 10 inches; very dark grayish brown (10YR 3/2) very The depth to bedrock is 60 inches or more. The cobbly clay loam, brown (10YR 5/3) dry; moderate very particle-size control section contains 35 to 60 percent fine and fine subangular blocky structure; slightly hard, clay and 35 to 60 percent rock fragments. The mollic firm, sticky and plastic; common very fine and few fine epipedon is 20 to 30 inches thick. roots; common very fine and fine tubular and few fine The A horizon has hue of 10YR, 7.5YR, or 2.5Y; value of irregular pores; few faint clay films on faces of peds; 20 2 or 3 moist, 3 to 5 dry; and chroma of 2 or 3 moist and dry. percent gravel and 15 percent cobbles; moderately acid The upper part of the Bt horizon has hue of 10YR, 7.5YR, or (pH 6.0); abrupt smooth boundary. 2.5Y; value of 3 or 4 moist, 3 to 6 dry; and chroma of 2 to 6 Bt1-10 to 20 inches; dark brown (10YR 3/3) very cobbly clay moist and dry. It is very cobbly clay loam or very cobbly clay. loam, brown (10YR 4/3) dry; strong very fine and fine The lower part of the Bt horizon and the BCt horizon have subangular blocky structure; hard, firm, sticky and very hue of 10YR or 2.5Y; value of 4 or 5 moist, 6 to 8 dry; and plastic; few very fine and fine roots; common very fine chroma of 3 or 4 moist and dry. They are gravelly clay loam, and fine tubular and common fine irregular pores; many gravelly loam, or very cobbly clay loam and contain 20 to 35 distinct clay films on faces of peds and in pores; 25 percent clay. percent gravel and 20 percent cobbles; moderately acid (pH 5.8); clear smooth boundary. Takilma Series Bt2-20 to 29 inches; brown (10YR 4/3) very cobbly clay, brown (10YR 4/3) dry; common fine distinct gray (10YR The Takilma series consists of very deep, well drained 5/1) mottles; moderate medium and coarse angular soils on stream terraces. These soils formed in alluvium. blocky structure; very hard, firm, very sticky and very Slopes are 0 to 3 percent. The mean annual precipitation is plastic; few very fine, fine, and medium roots; few very about 24 inches, and the mean annual temperature is fine tubular pores; many distinct and prominent clay about 52 degrees F. films on faces of peds and in pores; common Typical pedon of Takilma cobbly loam, 0 to 3 percent slickensides; 20 percent gravel and 15 percent cobbles; moderately acid (pH 5.6); clear wavy boundary. slopes, about 3 miles south of Ruch; about 1,380 feet east Tallowbox Series and 625 feet south of the northwest corner of sec. 10, T. 39 S., R. 3 W. The Tallowbox series consists of moderately deep, somewhat excessively drained soils on hillslopes and Ap-0 to 6 inches; very dark grayish brown (10YR 3/2) ridges. These soils formed in colluvium derived from cobbly loam, brown (10YR 5/3) dry; moderate fine and granitic rock. Slopes are 20 to 70 percent. The mean medium granular and moderate medium subangular annual precipitation is about 32 inches, and the mean blocky structure; slightly hard, very friable, nonsticky annual temperature is about 50 degrees F. and nonplastic; many roots; many irregular pores; 15 Typical pedon of Tallowbox gravelly sandy loam, 35 to percent gravel and 10 percent cobbles; slightly acid (pH 70 percent north slopes, about 8 miles southeast of Ruch; 6.2); abrupt smooth boundary. about 490 feet north and 1,190 feet east of the southwest Bw-6 to 15 inches; very dark grayish brown (10YR 3/2) very corner of sec. 30, T. 39 S., R. 2 W. cobbly loam, brown (10YR 5/3) dry; weak medium subangular blocky structure; slightly hard, very friable, Oi-1 inch to 0; leaves, needles, and twigs. nonsticky and nonplastic; common very fine and fine A-0 to 6 inches; dark brown (7.5YR 3/2) gravelly sandy roots; common fine and medium irregular pores; 30 loam, pale brown (10YR 6/3) dry; strong fine granular percent gravel and 20 percent cobbles; slightly acid (pH structure; soft, friable, nonsticky and nonplastic; many 6.4); clear smooth boundary. very fine and fine roots; many very fine irregular pores; BC-15 to 24 inches; brown (10YR 4/3) extremely cobbly 15 percent gravel; slightly acid (pH 6.5); abrupt smooth sandy loam, yellowish brown (10YR 5/4) dry; weak boundary. medium subangular blocky structure; soft, very friable, BA-6 to 12 inches; dark brown (7.5YR 3/4) sandy loam, light nonsticky and nonplastic; common very fine and fine yellowish brown (10YR 6/4) dry; moderate very fine and roots; many irregular pores; 35 percent gravel and 30 fine subangular blocky structure; slightly hard, friable, percent cobbles; neutral (pH 6.6); clear wavy boundary. slightly sticky and slightly plastic; common fine and C1-24 to 34 inches; brown (10YR 4/3) very gravelly sandy medium roots; common very fine and fine irregular loam, yellowish brown (10YR 5/4) dry; single grain; pores; 10 percent gravel; slightly acid (pH 6.4); loose, very friable, nonsticky and nonplastic; few very clearwavy boundary. fine roots; common irregular pores; 40 percent gravel Bw1-12 to 17 inches; brown (7.5YR 4/4) gravelly sandy and 15 percent cobbles; neutral (pH 6.6); gradual wavy loam, light brown (7.5YR 6/4) dry; moderate fine and boundary. medium subangular blocky structure; hard, friable, C2-34 to 60 inches; dark yellowish brown (10YR 4/4) slightly sticky and slightly plastic; common very fine, extremely gravelly sandy loam, yellowish brown (10YR fine, and medium roots; common very fine and fine 5/4) dry; single grain; loose, nonsticky and nonplastic; tubular pores; 20 percent gravel; moderately acid (pH few roots; many fine irregular pores; 60 percent gravel 5.7); clear wavy boundary. and 20 percent cobbles; neutral (pH 6.6). Bw2-17 to 23 inches; brown (7.5YR 4/4) gravelly sandy loam, light brown (7.5YR 6/4) dry; moderate fine and The depth to bedrock is 60 inches or more. The medium subangular blocky structure; hard, friable, particle-size control section contains 50 to 80 percent slightly sticky and slightly plastic; few roots; common rock fragments and 12 to 18 percent clay. The mollic very fine and fine tubular pores; 25 percent gravel; epipedon is 12 to 20 inches thick. moderately acid (pH 5.6); clear wavy boundary. The A horizon has hue of 7.5YR or 10YR; value of 2 or 3 Cr-23 inches; decomposed granitic rock. moist, 4 or 5 dry; and chroma of 2 or 3 moist, 2 to 4 dry. The Bw horizon has hue of 7.5YR or 10YR, value of 4 or 5 dry, The depth to bedrock is 20 to 40 inches. The and chroma of 2 or 3 moist, 3 or 4 dry. It is very cobbly loam particle-size control section contains 8 to 12 percent or very cobbly clay loam. The BC and C horizons have hue clay and 0 to 35 percent rock fragments. of 7.5YR or 10YR; value of 3 or 4 moist, 5 or 6 dry; and The A horizon has hue of 10YR or 7.5YR; value of 3 or 4 chroma of 3 or 4 moist and dry. They are very gravelly moist, 4 to 6 dry; and chroma of 2 or 3 moist and dry. The sandy loam, extremely gravelly sandy loam, or extremely Bw horizon has hue of 10YR, 7.5YR, or 2.5Y; value of 4 or cobbly sandy loam. 5 moist, 5 or 6 dry; and chroma of 3 to 6 moist and dry. It is gravelly sandy loam, gravelly coarse sandy loam, or sandy loam. Tatouche Series distinct clay films on faces of peds and in pores; moderately acid (pH 5.8); gradual wavy boundary. The Tatouche series consists of very deep, well 2C-60 to 73 inches; strong brown (7.5YR 4/6) clay loam, drained soils on hillslopes. These soils formed in yellowish brown (10YR 5/5) dry; massive; hard, firm, colluvium derived from igneous rock. Slopes are 12 to 65, sticky and plastic; 5 percent soft gravel; common percent. The mean annual precipitation is about 40 black stains; moderately acid (pH 5.6). inches, and the mean annual temperature is about 43 degrees F. The depth to bedrock is 60 inches or more. The Typical pedon of Tatouche gravelly loam, in an area of particle-size control section contains 35 to 50 percent Bybee-Tatouche complex, 12 to 35 percent north slopes, clay and 10 to 30 percent rock fragments. about 10 miles southeast of Ashland along an access road The A horizon has hue of 10YR or 7.5YR; value of 2 or 3 to the north end of a railroad tunnel at Siskiyou Summit; moist, 3 or 4 dry; and chroma of 2 or, 3 moist and dry. Some about 990 feet north and 1,590 feet west of the southeast pedons have a 2Bt horizon. The Bt and 2Bt horizons have corner of sec. 20, T. 40 S., R. 2 E. hue of 10YR, 7.5YR, or 5YR; value of 3 or 4 moist, 4 or 5 dry; and chroma of 3 or 4 moist and dry. They are clay, clay Oi-2 inches to 0; twigs and needles. loam, or gravelly clay loam. The 2C horizon is clay loam or A1-0 to 5 inches; very dark brown (10YR 2/2) gravelly loam, gravelly clay loam. dark grayish brown (10YR 4/2) dry; strong fine and very fine granular structure; slightly hard, friable, slightly Terrabella Series sticky and slightly plastic; many fine and medium roots; many very fine pores; 20 percent gravel and 5 percent The Terrabella series consists of very deep, poorly cobbles; neutral (pH 6.6); abrupt smooth boundary. drained soils in basins. These soils formed in alluvium A2-5 to 11 inches; very dark brown (10YR 2/2) gravelly derived from igneous rock. Slopes are 0 to 3 percent. The loam, dark grayish brown (10YR 4/2) dry; moderate mean annual precipitation is about 35 inches, and the very fine and fine subangular blocky structure; slightly mean annual temperature is about 49 degrees F. hard, friable, sticky and plastic; common fine and Typical pedon of Terrabella clay loam, 0 to 3 percent medium roots; many very fine tubular pores; 10 percent slopes, about 5.5 miles northeast of Butte Falls, along Butte gravel and 5 percent cobbles; slightly acid (pH 6.5); Falls-Prospect Highway; about 2,270 feet south and 1,625 clear smooth boundary. feet west of the northeast corner of sec. 21, T. 34 S., R. 3 Bt1-11 to 19 inches; dark brown (7.5YR 3/4) gravelly clay E. loam, dark brown (10YR 4/3) dry; moderate medium and fine subangular blocky structure; hard, firm, sticky Oi-1 inch to 0; grass root mat. and plastic; common medium and few fine and coarse A-0 to 5 inches; very dark brown (10YR 2/2) clay loam, very roots; few very fine tubular pores; 10 percent gravel and dark grayish brown (10YR 3/2) dry; few fine prominent 5 percent cobbles; few distinct and faint clay films on reddish yellow (5YR 6/8) and few fine distinct red faces of peds and in pores; slightly acid (pH 6.4); clear (2.5YR 4/8) mottles; strong fine granular structure; hard, smooth boundary. very friable, sticky and plastic; many very fine and few Bt2-19 to 34 inches; dark brown (7.5YR 4/4) clay, dark fine roots; many very fine and common fine irregular brown (10YR 4/4) dry; moderate medium and fine pores; 5 percent gravel; moderately acid (pH 5.6); clear subangular blocky structure; very hard, firm, very sticky smooth boundary. and very plastic; common medium and few fine and BA-5 to 10 inches; very dark brown (7.5YR 2/2) clay loam, coarse roots; many very fine tubular pores; 10 percent dark brown (7.5YR 3/2) dry; few fine distinct red (2.5YR soft gravel; common distinct clay films on faces of peds 4/8) mottles; moderate very fine and fine subangular and in pores; slightly acid (pH 6.2); gradual wavy blocky structure; very hard, firm, sticky and very plastic; boundary. common very fine and few fine, medium, and coarse Bt3-34 to 60 inches; dark brown (7.5YR 4/4) clay, brown roots; few very fine irregular pores; few stress surfaces; (7.5YR 5/4) dry; weak medium and coarse subangular 5 percent gravel; moderately acid (pH 5.6); clear smooth blocky structure; very hard, firm, very sticky and very boundary. plastic; few roots; many very fine tubular pores; 10 Bt1-10 to 16 inches; dark reddish brown (5YR 3/3) clay, dark percent soft gravel; common reddish gray (5YR 4/2) dry; few fine distinct yellowish red (5YR 5/8) and red (2.5YR 4/8) mottles; strong medium subangular blocky structure; very hard, firm, very sticky and very plastic; few very fine, fine, medium, and coarse roots; few very fine tubular pores; many faint clay films in pores; 5 percent north slopes, about 17 miles north of Gold Hill; percent gravel; slightly acid (pH 6.2); clear smooth about 2,300 feet east and 1,200 feet north of the boundary. southwest corner of sec. 19, T. 33 S., R. 3 W. Bt2-16 to 28 inches; dark reddish gray (5YR 4/2) clay, reddish gray (5YR 5/2) dry; few fine distinct yellowish Oi-1 inch to 0; needles, leaves, and twigs. red (5YR 5/8), very dark gray (5YR 3/1), and red A1-0 to 2 inches; dark grayish brown (10YR 4/2) sandy (2.5YR 4/8) mottles; strong medium and coarse loam, grayish brown (10YR 5/2) dry; strong fine and prismatic structure; extremely hard, extremely firm, very medium granular structure; slightly hard, very friable, sticky and very plastic; few medium and coarse roots; nonsticky and nonplastic; common very fine, fine, few very fine tubular pores; continuous prominent clay medium, and coarse roots; many very fine and fine films in pores; 5 percent gravel; slightly acid (pH 6.3); irregular pores; moderately acid (pH 5.8); abrupt gradual smooth boundary. smooth boundary. Bt3-28 to 50 inches; dark brown (7.5YR 3/4) clay, brown A2-2 to 10 inches; brown (10YR 4/3) sandy loam, very pale (7.5YR 5/4) dry; common fine distinct yellowish red brown (10YR 7/3) dry; moderate very fine and fine (5YR 5/6) and few fine distinct yellowish red (5YR 5/8) subangular blocky structure; slightly hard, very friable, mottles; weak coarse angular blocky structure; nonsticky and nonplastic; common very fine, fine, extremely hard, extremely firm, very sticky and very medium, and coarse roots; many very fine and fine plastic; few medium roots; few very fine tubular pores; irregular pores; moderately acid (pH 5.6); abrupt continuous prominent clay films on faces of peds and in smooth boundary. pores; 5 percent gravel; slightly acid (pH 6.3); diffuse Bw1-10 to 21 inches; yellowish brown (10YR 5/4) sandy smooth boundary. loam, very pale brown (10YR 7/4) dry; moderate C-50 to 60 inches; dark yellowish brown (10YR 4/4) gravelly very fine and fine subangular blocky structure; clay loam, light yellowish brown (10YR 6/4) dry; many slightly hard, very friable, nonsticky and nonplastic; medium distinct yellowish red (5YR 5/6) mottles; few very fine, fine, and medium roots; common very massive; very hard, firm, sticky and plastic; 15 percent fine and fine irregular pores; moderately acid (pH gravel; slightly acid (pH 6.4). 5.6); clear smooth boundary. Bw2-21 to 31 inches; light yellowish brown (10YR 6/4) The depth to bedrock is 60 inches or more. The soils are sandy loam, very pale brown (10YR 8/4) dry; weak very saturated to the surface for at least 1 month in most years. fine and fine subangular blocky structure; slightly hard, The particle-size control section contains 40 to 55 percent very friable, nonsticky and nonplastic; few very fine, clay. In most years the soils have cracks that are open to fine, and medium roots; common very fine and fine the surface or to the base of a plow layer. These cracks are irregular pores; strongly acid (pH 5.2); clear smooth at least 1 centimeter wide at a depth of 20 inches. The soils boundary. do not have intersecting slickensides. Bw3-31 to 49 inches; very pale brown (10YR 7/3) sandy The A horizon has hue of 10YR or 7.5YR; value of 2 or 3 loam, very pale brown (10YR 8/3) dry; weak very fine moist, 3 or 4 dry; and chroma of 2 or 3 moist and dry. The Bt and fine subangular blocky structure; slightly hard, horizon has hue of 7.5YR or 5YR; value of 3 or 4 moist, 4 or very friable, nonsticky and nonplastic; few fine and 5 dry; and chroma of 2 to 4 moist and dry. The C horizon medium roots; common very fine and fine irregular has hue of 5YR, 7.5YR, or 10YR; value of 4 or 5 moist, 6 or pores; strongly acid (pH 5.1); clear smooth boundary. 7 dry; and chroma of 3 or 4 moist and dry. It is clay loam, C-49 to 60 inches; very pale brown (10YR 7/3) sandy clay, or gravelly clay loam and contains 0 to 20 percent loam, very pale brown (10YR 8/3) dry; massive; hard, gravel. very friable, nonsticky and nonplastic; few very fine and fine irregular pores; strongly acid (pH 5.1). Tethrick Series The depth to bedrock is 60 inches or more. The The Tethrick series consists of very deep, well drained particle-size control section contains 5 to 18 percent soils on hillslopes. These soils formed in colluvium derived clay, 5 to 20 percent rock fragments, and 15 to 50 from granitic rock. Slopes are 35 to 75 percent. The mean percent coarse sand and very coarse sand. annual precipitation is about 45 inches, and the mean The A horizon has hue of 10YR or 2.5Y; value of 3 to annual temperature is about 49 degrees F. 6 moist, 5 to 7 dry; and chroma of 2 or 3 moist and dry. Typical pedon of Tethrick sandy loam, 35 to 75 The Bw and C horizons have hue of 10YR, 2.5Y, or 5Y; value of 4 to 7 moist, 5 to 8 dry; and chroma of 2 to 6 moist and dry. They are coarse sandy loam or sandy pores; common distinct red (2.5YR 4/6) clay films on loam. faces of peds and on soft rock fragments; 30 percent soft rock fragments; moderately acid (pH 6.0); gradual Vannoy Series wavy boundary. 2BCt-35 to 38 inches; yellowish red (5YR 4/6) clay loam, The Vannoy series consists of moderately deep, well yellowish red (5YR 4/6) dry; massive; very hard, firm, drained soils on hillslopes. These soils formed in colluvium sticky and plastic; few fine roots; many very fine and derived from altered sedimentary and volcanic rock. Slopes fine tubular pores; common distinct red (2.5YR 4/6) are 12 to 55 percent. The mean annual precipitation is about clay films on soft rock fragments; 75 percent soft rock 32 inches, and the mean annual temperature is about 50 fragments; many black stains on pebbles; moderately degrees F. acid (pH 5.9); gradual wavy boundary. Typical pedon of Vannoy silt loam, 12 to 35 percent 2Crt-38 inches; weathered, highly fractured, north slopes, about 1 mile southwest of Jacksonville and metamorphosed rock; many prominent dark red (2.5YR 1,580 feet east of State Highway 238; about 2,340 feet 3/6) clay films and many black stains in fracture planes. east and 3,100 feet south of the northwest corner of sec. 31, T. 37 S., R. 2 W. The depth to bedrock is 20 to 40 inches. The particle-size control section contains 27 to 35 percent Oi-3/4 inch to 0; needles, leaves, and twigs. clay and 5 to 35 percent rock fragments. A1-0 to 2 inches; dark brown (7.5YR 4/3) silt loam, pale The A horizon has hue of 7.5YR or 10YR; value of 3 or brown (10YR 6/3) dry; moderate fine granular structure; 4 moist, 5 to 7 dry; and chroma of 2 to 4 moist, 3 or 4 dry. slightly hard, friable, sticky and slightly plastic; many The 2Bt horizon has hue of 7.5YR or 5YR; value 9f 4 or 5 very fine and fine roots; many very fine irregular pores; moist, 5 or 6 dry; and chroma of 4 to 6 moist and dry. 5 percent gravel; slightly acid (pH 6.5); abrupt wavy boundary. Voorhies Series A2-2 to 4 inches; dark brown (7.5YR 4/4) silt loam, pale brown (10YR 6/3) dry; weak medium and moderate fine The Voorhies series consists of moderately deep, well granular structure; slightly hard, friable, slightly sticky drained soils on hillslopes. These soils formed in colluvium and slightly plastic; many fine roots; many fine irregular derived from altered sedimentary and volcanic rock. Slopes and common very fine tubular pores; 5 percent gravel; are 35 to 55 percent. The mean annual precipitation is about slightly acid (pH 6.3); clear smooth boundary. 32 inches, and the mean annual temperature is about 50 BA-4 to 11 inches; reddish brown (5YR 4/4) silt loam, light degrees F. brown (7.5YR 6/4) dry; weak medium and fine Typical pedon of Voorhies very gravelly loam, in an area subangular blocky structure; hard, friable, slightly sticky of Vannoy-Voorhies complex, 35 to 55 percent south and slightly plastic; common fine roots; many fine and slopes, about 6 miles southwest of Medford, at the head of very fine tubular pores; 5 percent gravel; strongly acid Griffin Creek; about 1,680 feet west and 790 feet south of (pH 5.4); clear smooth boundary. the northeast corner of sec. 35, T. 38 S., R. 2 W. 2Bt1-11 to 19 inches; yellowish red (5YR 4/6) clay loam, yellowish red (5YR 5/6) dry; moderate fine subangular Oi-1 inch to 0; needles and twigs. blocky structure; very hard, friable, sticky and plastic; A1-0 to 3 inches; very dark grayish brown (10YR 3/2) very common fine and medium roots; many very fine tubular gravelly loam, grayish brown (10YR 5/2) dry; weak fine pores; common distinct clay films on faces of peds; 5 and moderate very fine granular structure; soft, very percent soft gravel; moderately acid (pH 5.6); clear friable, slightly sticky and slightly plastic; many fine and smooth boundary. very fine and few medium roots; many fine irregular 2Bt2-19 to 26 inches; yellowish red (5YR 4/6) clay loam, pores; 55 percent gravel; neutral (pH 6.8); clear smooth yellowish red (5YR 5/6) dry; moderate fine subangular boundary. blocky structure; very hard, firm, sticky and plastic; A2-3 to 8 inches; dark brown (10YR 3/3) very gravelly loam, common fine and medium roots; many very fine tubular brown (10YR 5/3) dry; weak fine granular and pores; common distinct clay films on faces of peds; 12 subangular blocky structure; soft, very friable, slightly percent soft gravel; moderately acid (pH 6.0); clear sticky and slightly plastic; many fine and few medium smooth boundary. roots; many fine irregular and very fine 2Bt3-26 to 35 inches; yellowish red (5YR 4/6) clay loam, yellowish red (5YR 5/6) dry; moderate fine subangular blocky structure; very hard, firm, sticky and plastic; few fine roots; many very fine tubular tubular pores; 55 percent gravel; neutral (pH 6.8); clear subangular blocky structure; slightly hard, friable, smooth boundary. slightly sticky and slightly plastic; many very fine and BA-8 to 12 inches; brown (7.5YR 4/3) very gravelly clay few fine and medium roots; many very fine irregular loam, light brown (7.5YR 6/3) dry; moderate fine pores; 10 percent gravel and 10 percent cobbles; subangular blocky structure; slightly hard, friable, sticky moderately acid (pH 5.6); abrupt wavy boundary. and slightly plastic; common fine and few medium AB-8 to 12 inches; dark brown (7.5YR 3/3) gravelly loam, roots; many very fine tubular pores; 40 percent gravel; brown (10YR 5/3) dry; moderate very fine and fine thin bleached silt and sand grains on peds; slightly acid angular blocky structure; hard, firm, sticky and plastic; (pH 6.4); gradual wavy boundary. common very fine and few fine and medium roots; many Bt1-12 to 18 inches; brown (7.5YR 4/3) very gravelly clay very fine irregular pores; 15 percent gravel; moderately loam, light yellowish brown (10YR 6/4) dry; moderate acid (pH 5.8); abrupt wavy boundary. medium subangular blocky structure; hard, firm, sticky 2Bt-12 to 16 inches; dark brown (7.5YR 3/3) gravelly clay and plastic; common fine and few medium roots; loam, brown (10YR 5/3) dry; moderate very fine and common very fine and fine tubular pores; few faint clay fine angular blocky structure; hard, firm, sticky and films on faces of peds; 35 percent gravel and 10 plastic; common very fine and few fine and medium percent cobbles; slightly acid (pH 6.4); clear smooth roots; many very fine irregular pores; common faint clay boundary. films on faces of peds and in pores; 15 percent gravel; Bt2-18 to 36 inches; brown (7.5YR 4/4) very cobbly clay moderately acid (pH 5.8); abrupt wavy boundary. loam, pink (7.5YR 7/3) dry; moderate medium 2Bqm-16 to 23 inches; indurated, gravelly duripan. subangular blocky structure; hard, firm, sticky and slightly plastic; few fine and medium roots; common Depth to the duripan is 10 to 20 inches. The depth to very fine and fine tubular pores; common faint and few bedrock is 60 inches or more. The particle-size control distinct clay films on faces of peds and in pores; 30 section contains 25 to 35 percent clay and 15 to 35 percent percent gravel and 25 percent cobbles; neutral (pH rock fragments. 6.6); gradual wavy boundary. The A horizon has hue of 10YR or 7.5YR; value of 2 or 3 Cr-36 inches; partially consolidated, weathered moist, 4 or 5 dry; and chroma of 2 or 3 moist and dry. The metamorphic rock. AB and 2Bt horizons have hue of 10YR or 7.5YR; value of 3 or 4 moist, 4 to 6 dry; and chroma of 2 or 3 moist and dry. The depth to bedrock is 20 to 40 inches. The They are gravelly loam or gravelly clay loam. particle-size control section contains 25 to 35 percent clay and 35 to 60 percent rock fragments. Winlo Series The A horizon has hue of 10YR or 7.5YR; value of 3 or 4 moist, 4 to 6 dry; and chroma of 2 to 4 moist and dry. The The Winlo series consists of somewhat poorly drained Bt horizon has hue of 10YR, 7.5YR, or 5YR; value of 4 or 5 soils on fan terraces. These soils are in between mounds moist, 5 to 7 dry; and chroma of 3 to 6 moist and dry. It is in areas of patterned ground. They are shallow to a very gravelly clay loam, very cobbly clay loam, or very duripan. They formed in stratified alluvium. Slopes are 0 cobbly loam. to 3 percent. The mean annual precipitation is about 24 inches, and the mean annual temperature is about 53 Whiteface Series degrees F. Typical pedon of Winlo very gravelly clay loam, in an The Whiteface series consists of well drained soils on area of Agate-Winlo complex, 0 to 5 percent slopes, about alluvial fans. These soils are shallow to a duripan. They 500 feet west and 200 feet south of the intersection of formed in alluvium derived from igneous rock. Slopes are Table Rock Road and Kirtland Road; about 1,150 feet east 1 to 12 percent, The mean annual precipitation is about and 440 feet north of the southwest corner of sec. 13, T. 36 30 inches, and the mean annual temperature is about 42 S., R. 2 W. degrees F. Typical pedon of Whiteface cobbly loam, in an area of A-0 to 4 inches; very dark grayish brown (10YR 3/2) very Aspen lake-Whiteface complex, 1 to 12 percent slopes, gravelly clay loam, grayish brown (10YR 5/2) dry; many north of Aspen Lake; about 500 feet east and 1,550 feet fine distinct strong brown (7.5YR 5/6) mottles; strong south of the northwest corner of sec. 21, T. 37 S., R. 7 E. fine and very fine granular structure; hard, firm, sticky and plastic; many fine and very A-0 to 8 inches; dark brown (7.5YR 3/2) cobbly loam, brown (10YR 4/3) dry; moderate very fine and fine fine roots; 30 percent gravel and 10 percent cobbles; mean annual temperature is about 49 degrees F. slightly acid (pH 6.2); clear smooth boundary. Typical pedon of Wolfpeak sandy loam, 12 to 35 Bw-4 to 9 inches; dark brown (7.5YR 3/2) very gravelly percent south slopes; about 2,400 feet east and 500 feet clay, brown (7.5YR 5/2) dry; few fine distinct strong south of the northwest corner of sec. 21, T. 33 S., R. 3 W. brown (7.5YR 5/6) mottles; weak medium subangular blocky structure; very hard, very firm, very sticky and Oi-1/2 inch to 0; needles, leaves, and twigs. very plastic; common fine and very fine roots; 40 A-0 to 4 inches; dark brown (10YR 3/3) sandy loam, brown percent gravel and 10 percent cobbles; slightly acid (10YR 5/3) dry; strong fine granular structure; slightly (pH 6.4); abrupt smooth boundary. hard, friable, slightly sticky and nonplastic; many very 2Bqm-9 to 17 inches; yellowish red (5YR 4/6), indurated fine and fine and common medium and coarse roots; duripan, yellowish red (5YR 5/6) dry; massive; medium many very fine irregular pores; 13 percent gravel; and fine nearly continuous silica laminae; common fine moderately acid (pH 5.6); clear smooth boundary. black stains; 40 percent gravel and 20 percent BA-4 to 11 inches; brown (7.5YR 4/4) sandy loam, very pale cobbles; clear smooth boundary. brown (10YR 7/4) dry; strong fine subangular blocky 2C1-17 to 42 inches; light olive brown (2.5Y 5/4) extremely structure; slightly hard, friable, slightly sticky and gravelly coarse sandy loam, very pale brown (10YR nonplastic; many very fine and fine and common 7/4) and yellow (10YR 7/6) dry; massive; slightly hard, medium and coarse roots; many very fine irregular very friable, nonsticky and nonplastic; discontinuous pores; 10 percent gravel; strongly acid (pH 5.4); clear weakly cemented silica laminae; 55 percent gravel and wavy boundary. 25 percent cobbles; neutral (pH 6.6); gradual smooth Bt1-11 to 35 inches; yellowish brown (10YR 5/4) clay loam, boundary. very pale brown (10YR 7/4) dry; moderate medium and 2C2-42 to 60 inches; light olive brown (2.5Y 5/4) extremely coarse subangular blocky structure; hard, firm, sticky gravelly coarse sandy loam, pale yellow (2.5Y 7/4) dry; and plastic; common very fine and fine and few medium massive; slightly hard, very friable, nonsticky and and coarse roots; common very fine tubular pores; nonplastic; 55 percent gravel and 25 percent cobbles; many distinct clay films in pores and on faces of peds; neutral (pH 6.6). 10 percent gravel and 3 percent cobbles; strongly acid (pH 5.4); gradual wavy boundary. Depth to the duripan is 7 to 15 inches. The depth to Bt2-35 to 60 inches; strong brown (7.5YR 5/6) clay loam, bedrock is 60 inches or more. The soils are saturated to the yellow (10YR 7/6) dry; moderate medium and coarse surface for at least 1 month in most years. The particle-size subangular blocky structure; hard, firm, sticky and control section contains 35 to 60 percent rock fragments plastic; few very fine and fine roots; common very fine and 40 to 50 percent clay. tubular pores; many distinct clay films in pores and on The A horizon has hue of 10YR or 7.5YR; value of 2 or 3 faces of peds; 10 percent gravel and 3 percent cobbles; moist, 4 or 5 dry; and chroma of 1 or 2 moist and dry. The strongly acid (pH 5.4). Bw horizon has hue of 10YR or 7.5YR, value of 4 or 5 dry, and chroma of 1 or 2 moist and dry. The duripan is The depth to bedrock is 60 inches or more. The indurated throughout or only in some part. It exhibits strong particle-size control section contains 25 to 35 percent cementation. The 2C horizon has hue of 2.5Y, 10YR, clay and 5 to 25 percent rock fragments. 7.5YR, or 5YR; value of 4 to 6 moist, 6 or 7 dry; and The A and BA horizons have hue of 10YR or 7.5YR; chroma of 4 or 5 moist, 4 to 6 dry. It generally is coarse value of 3 to 5 moist, 4 to 7 dry; and chroma of 2 to 4 moist sandy loam or loamy sand in the fine-earth fraction and and dry. The Bt horizon has hue of 10YR, 7.5YR, or 5YR; contains 50 to 60 percent gravel and 10 to 30 percent value of 4 to 6 moist, 5 to 7 dry; and chroma of 4 to 8 moist cobbles. In some pedons it has strata of loam or silt loam. and dry. It is loam, clay loam, or gravelly clay loam.

Wolfpeak Series Woodcock Series

The Wolfpeak series consists of very deep, well drained The Woodcock series consists of very deep, well soils on hillslopes and alluvial fans. These soils formed in drained soils on plateaus and hillslopes. These soils alluvium, colluvium, and residuum derived from granitic formed in colluvium derived from igneous rock. Slopes are rock. Slopes are 3 to 35 percent. The mean annual 1 to 55 percent. The mean annual precipitation is precipitation is about 45 inches, and the about 30 inches, and the mean annual temperature is pores; 15 percent gravel; slightly acid (pH 6.1); clear about 43 degrees F. smooth boundary. Typical pedon of Woodcock stony loam, in an area of 3C-48 to 62 inches; dark reddish brown (2.5YR 2.5/4) Pokegema-Woodcock complex, 1 to 12 percent slopes, gravelly clay loam, dusky red (2.5YR 3/2) dry; massive; about 3 miles northeast of Pinehurst; about 1,300 feet soft, friable, sticky and slightly plastic; few medium south and 1,800 feet west of the northeast corner of roots; few fine tubular pores; 15 percent gravel; sec. 27, T. 39 S., R. 4 E. moderately acid (pH 5.8).

Oi-1 inch to 0; needles and twigs. The depth to bedrock is 60 inches or more. The A1-0 to 4 inches; dark reddish brown (5YR 3/2) stony particle-size control section contains 25 to 35 percent loam, reddish brown (5YR 4/3) dry; moderate medium clay and 50 to 75 percent rock fragments. The mollic and fine granular structure; soft, friable, slightly sticky epipedon is 16 to 30 inches thick. and slightly plastic; many very fine and fine roots; The A horizon has hue of 10YR, 7.5YR, or 5YR; value of many fine irregular pores; 5 percent gravel and 5 2 or 3 moist, 3 to 5 dry; and chroma of 2 to 4 moist, 1 to 4 percent cobbles; stones covering 5 percent of the dry. The 2Bt horizon has hue of 10YR, 7.5YR, or 5YR; surface; neutral (pH 6.8); abrupt smooth boundary. value of 2 to 4 moist, 4 to 6 dry; and chroma of 2 to 4 moist A2-4 to 16 inches; dark reddish brown (5YR 3/2) very and dry. It is very gravelly loam, very gravelly clay loam, or gravelly loam, reddish brown (5YR 4/3) dry; weak fine extremely gravelly loam. and medium granular structure; soft, friable, slightly sticky and slightly plastic; many fine roots; many fine Woodseye Series irregular pores; 30 percent gravel and 5 percent cobbles; neutral (pH 7.0); clear smooth boundary. The Woodseye series consists of shallow, somewhat 2BA-1 6 to 20 inches; dark reddish brown (5YR 3/3) very excessively drained soils on hillslopes. These soils formed gravelly clay loam, reddish brown (5YR 4/4) dry; in colluvium derived from igneous rock. Slopes are 3 to 80 moderate medium and fine subangular blocky percent. The mean annual precipitation is about 43 inches, structure; slightly hard, friable, sticky and slightly and the mean annual temperature is about 43 degrees F. plastic; common medium, fine, and very fine roots; Typical pedon of Woodseye very stony loam, in an area common fine tubular pores; 50 percent gravel and 5 of Woodseye-Rock outcrop complex, 3 to 35 percent slopes, percent cobbles; slightly acid (pH 6.4); clear wavy about 1 mile north of Dead Indian Road; about 845 feet boundary. north and 2,215 feet east of the southwest corner of sec. 8, 2Bt1-20 to 32 inches; dark reddish brown (5YR 3/4) very T. 38 S., R. 3 E. gravelly clay loam, reddish brown (5YR 4/4) dry; moderate medium and fine subangular blocky A1-0 to 2 inches; dark brown (7.5YR 3/2) very stony loam, structure; hard, friable, sticky and plastic; common brown (10YR 5/3) dry; weak thin platy structure; soft, medium and few fine roots; common fine tubular friable; slightly sticky and slightly plastic; few very fine pores; few faint clay films on faces of peds; 50 roots; many very fine vesicular pores; 5 percent gravel, percent gravel and 5 percent cobbles; slightly acid 5 percent cobbles, and 25 percent stones; slightly acid (pH 6.2); clear smooth boundary. (pH 6.2); abrupt smooth boundary. 2Bt2-32 to 39 inches; dark reddish brown (5YR 3/4) very A2-2 to 8 inches; dark brown (7.5YR 3/3) very cobbly loam, gravelly clay loam, reddish brown (5YR 4/4) dry; brown (10YR 4/3) dry; weak fine subangular blocky moderate medium and fine subangular blocky structure parting to weak fine granular; soft, very friable, structure; slightly hard, friable, sticky and plastic; slightly sticky and slightly plastic; common very fine common medium and few fine roots; common fine roots; many very fine irregular pores; 10 percent gravel tubular pores; common faint clay films on faces of and 45 percent cobbles; slightly acid (pH 6.4); clear peds; 50 percent gravel and 5 percent cobbles; wavy boundary. slightly acid (pH 6.1); clear smooth boundary. Bw-8 to 18 inches; dark brown (7.5YR 3/4) very cobbly 3BC-39 to 48 inches; dark reddish brown (2.5YR 2.5/4) loam, brown (10YR 4/3) dry; weak fine subangular gravelly clay loam, reddish brown (2.5YR 4/4) dry; blocky structure parting to weak fine granular; soft, weak medium and fine subangular blocky structure; friable, slightly sticky and slightly plastic; common very slightly hard, friable, sticky and slightly plastic; few fine roots; few very fine tubular pores; 20 percent gravel medium roots; common fine tubular and 25 percent cobbles; slightly acid (pH 6.4); abrupt wavy boundary. R-18 inches; andesite. slightly hard, friable, slightly sticky and slightly plastic; many fine roots; many fine irregular pores; 10 percent The depth to bedrock is 10 to 20 inches. The gravel and 25 percent cobbles; moderately acid (pH particle-size control section contains 50 to 80 percent 5.8); clear wavy boundary. rock fragments and 18 to 27 percent clay. The umbric C1-6 to 18 inches; reddish brown (5YR 4/4) very cobbly clay epipedon is 7 to 16 inches thick. loam, light brown (7.5YR 6/4) dry; massive; very hard, The A horizon has hue of 10YR or 7.5YR; value of 2 or friable, sticky and plastic; common fine and medium 3 moist, 4 or 5 dry; and chroma of 2 or 3 moist and dry. roots; many very fine and fine irregular pores; 20 The Bw horizon has hue of 10YR or 7.5YR; value of 3 to 5 percent gravel and 35 percent cobbles; moderately acid moist, 4 to 6 dry; and chroma of 2 to 6 moist and dry. It is (pH 5.6); clear wavy boundary. very cobbly or extremely cobbly loam. C2-18 to 60 inches; reddish brown (5YR 4/4) extremely cobbly clay loam, light brown (7.5YR 6/4) dry; massive; Xerorthents very hard, firm, sticky and plastic; common fine and medium roots; many very fine and fine irregular pores; Xerorthents are very deep to moderately deep, well 30 percent gravel and 40 percent cobbles; moderately drained and moderately well drained soils on flood plains, acid (pH 5.6). stream terraces, and alluvial fans. These soils formed in material that was deposited after the landscape was The depth to bedrock is 20 inches or more. The control mined. This material commonly is referred to as mine section contains 25 to 90 percent rock fragments, of tailings. Slopes are 0 to 15 percent. The mean annual which 10 to 70 percent is cobbles. The particle-size precipitation is about 32 inches, and the mean annual control section contains 10 to 35 percent clay. temperature is about 50 degrees F. The A horizon has hue of 7.5YR or 10YR; value of 3 or 4 Reference pedon of Xerorthents, in an area of moist, 5 to 7 dry; and chroma of 2 to 4 moist and dry. In the Xerorthents-Dumps complex, 0 to 15 percent slopes, in a fine-earth fraction, it is clay loam to sandy clay. It contains mined stream basin about 6 miles south of Jacksonville; 25 to 90 percent rock fragments. The C horizon has hue of about 2,500 feet west and 600 feet north of the southeast 5YR to 10YR; value of 3 to 5 moist, 5 to 7 dry; and chroma corner of sec. 33, T. 38 S., R. 2 W. of 2 to 6 moist and dry. In the fine-earth fraction, it is clay loam to sandy loam. It contains 25 to 90 percent rock A-0 to 6 inches; dark brown (7.5YR 4/4) very cobbly clay fragments. loam, pale brown (10YR 6/3) dry; weak medium and moderate fine granular structure; Formation of the Soils

By Russell A. Almaraz, soil scientist, Soil Conservation Service. bases because the mineralogy of the parent material is mixed. The amount of precipitation is not high enough to Soil is a natural, three-dimensional body on the earth's leach most of the bases out of the soil profile. The soils in surface that supports plants. Its characteristics and this zone include those of the Vannoy series (Mollic properties are determined by physical and chemical Haploxeralfs) and those of the Caris series (Typic processes that result from the interaction of five Xerochrepts). Some of the soils are in Ultic subgroups of factors-climate, plant and animal life, parent material, Xerolls formed dominantly in material that is relatively low topography, and time. in content of bases. Examples are Medco soils (Ultic The influence of each factor varies from place to place. Haploxerolls) and Skookum soils (Pachic Ultic Argixerolis). Some factors are more influential than others. The interaction among all the factors determines the kind of Climate Zone 2 soil that forms. Parent material, climate, and topography This zone receives more than 35 inches of annual are responsible for most of the differences among the precipitation and generally is at elevations of about 4,000 soils in the survey area. feet. The soil temperature regime is mesic. The zone is In this section the effects of climate and of plant and characterized by hot, dry summers and cool, moist winters. animal life are described under separate headings. The Most of the precipitation in winter is received as rainfall. effects of time, parent material, and topography are The amount of precipitation is high enough to result in the described under the heading "Geomorphology." leaching of bases and the illuviation of clay. Among the soils in this zone are those of the McNull series (Ultic Climate Argixerolls), the Lettia series (Ultic Haploxeralfs), and the Beekman series (Dystric Xerochrepts). The most important climatic factors that affect soil formation are precipitation and temperature. Climate Climate Zone 3 controls the chemical and physical reactions that take This zone receives 20 to 60 inches of annual precipitation place in the soil. Temperature affects the rate of chemical and generally is at elevations between 3,500 and 6,000 feet. reactions and the movement of soil particles, such as that The soil temperature regime is frigid. The zone is caused by the freezing of water. Freezing and thawing of characterized by warm, dry summers and cold, moist water can cause the expansion and contraction of soil winters. Precipitation falls as rain most of the time; however, particles, thereby influencing the movement of both the much snow accumulates in some winters. Bases are readily particles and the rock fragments in the soil (4). The rate at leached from the soils because of the amount of which organic matter decomposes and accumulates is precipitation received. Cool temperatures slow the controlled by the temperature and moisture content of the decomposition of organic matter, which thus accumulates in soil. the soils. These processes contribute to the formation of This survey area has four major climate zones (fig. 18), such soils as those of the Donegan series (Pachic each of which has a distinctive influence on soil genesis. Xerumbrepts) and those of the Pinehurst series (Pachic These zones are described in this section. Ultic Argixerolls). In areas where the amount of precipitation is more limited, the leaching of bases is not so extensive. Climate Zone 1 The soils in these areas have relatively high base This zone receives less than 35 inches of annual saturation. Bly and Royst soils (Pachic Argixerolls) are precipitation and generally is at elevations of about 4,000 examples. feet. The soil temperature regime is mesic. The zone is characterized by hot, dry summers and cool, moist winters. Most of the precipitation is received as rainfall. Most of the soils contain a moderate amount of Figure 18.-The major climatic zones in the survey area.

Climate Zone 4 by cool, dry summers and cold, moist winters. Precipitation This zone generally receives less than 45 inches of occurs mainly as snow. The cold temperatures in this zone annual precipitation and in most areas is between significantly restrict the activity of micro-organisms. As a elevations of about 3,800 and 6,600 feet. The soil result, organic matter accumulates in the soils. Under temperature regime is cryic. The zone is characterized these conditions, soils that have a thick mollic epipedon form. An example is large amount of organic matter to the soil. The roots take up Pokegema soils (Pachic Cryoborolls). Physical weathering calcium and other bases, which are returned to the soil of bedrock through the freezing and thawing can result in annually when leaves and twigs drop to the ground in the soils that have many rock fragments and exhibit poor profile fall. This process helps to compensate for the loss of bases development. An example is Oatman soils (Dystric caused by leaching. The annual dieback of roots returns a Cryochrepts). large amount of organic matter to the soil. During periods of flooding, silt and sand high in content of organic matter are Plant and Animal Life deposited on the surface. These processes contribute to the formation of Mollisols. Newberg soils (Fluventic The kind and abundance of organisms living in or on the Haploxerolls), which are near streams, accumulate organic soil are dynamic factors of soil formation that are influenced matter and deposits of sand during periods of flooding. by the characteristics of the parent material, the climate, the Evans soils (Cumulic Haploxerolls) formed farther away topography, and the age of the soil. The composition of the from the streams, in backwash areas. Organic matter has organisms in and on the soil determines the kind and accumulated in these soils as a result of a dense plant cover amount of organic matter added to the soil. The breakdown and the deposition of silty material high in content of organic of organic residue releases the nutrients contained in the matter during periods of flooding. soil and results in continuous recycling of the nutrients. The The natural vegetation on the terraces and foothills in the plants and animals feeding on the organic debris become valleys is mainly hardwood trees and various shrubs, forbs, part of the total organic matter complex. In this survey area, and grasses (5). In most areas in the valleys, the proportion parent material and climate are the environmental factors of hardwood trees and grasses is significantly higher than that have the greatest effect on vegetation. the proportion of conifers. The organic matter derived from One of the most important roles of plants and animals in the deciduous trees and shrubs decomposes more readily soil formation is the differentiation of horizons in the soil under the influence of the warm temperatures in the valleys. profile. Earthworms, rodents, insects, micro-organisms, and As a result, plant nutrients are more rapidly recycled. The other organisms enhance important soil-forming processes, amount of annual rainfall is moderate. It does not result in such as the accumulation of organic matter, nutrient cycling, excessive leaching of bases. Examples of the soils in these stabilization of soil structure, profile mixing, and additions of areas are those of the Ruch series (Mollic Palexeralfs) and plant nutrients. They also influence soil acidity and improve those of the Barron series (Typic Xerochrepts). soil aeration and drainage. Because of complex climatic and In the soils on the uplands in this zone, accumulations of geologic patterns, the survey area has highly diverse plant organic matter are derived mainly from conifers, deciduous species and vegetative patterns (5). hardwoods, and shrubs. Nutrient cycling and limited The annual leaf drop of deciduous vegetation contributes precipitation have contributed to the formation of soils that significantly to the accumulation of organic matter in the soil. have high base saturation. Examples are Vannoy and The accumulation generally is greater in mixed stands of Voorhies soils (Mollic Haploxeralfs). hardwoods and conifers than in pure stands of conifers. The Climate zone 2. This zone is characterized by a low forests dominated by hardwoods commonly are at the lower proportion of deciduous hardwood trees and shrubs and a elevations. The warmer mean annual soil temperatures are high proportion of conifers. A high amount of annual likely to result in a large population of micro-organisms, precipitation and warm temperatures in this zone have which incorporate a large amount of organic matter into the resulted not only in the leaching of most bases but also in soil. the rapid decomposition of the organic matter on and in the The following paragraphs describe the effects of soils. Such soils as those of the Acker series (Typic vegetation on soil formation in the four climate zones in the Haploxerults), the Lettia series (Ultic Haploxeralfs), and the survey area. Beekman series (Dystric Xerochrepts) formed in this zone. Climate zone 1.-The interior valleys of the Rogue and Climate zone 3.-This zone dominantly supports conifers Applegate Rivers and of Evans and Bear Creeks are in and shrubs. Although the conifers generally supply the soils this zone. They are used mainly for cultivated crops and with enough bases, the amount of annual precipitation in urban development. The native vegetation, however, is this zone is high enough to leach many of the bases from still dominant in numerous areas. the profile. Such soils as those The riparian vegetation on the flood plains is mostly hardwood trees and numerous shrubs, forbs, and grasses (3). The deciduous vegetation contributes a of the Jayar and Rogue series (Dystric Xerochrepts) occur annually. The surface is characterized by low relief formed in this zone. and includes the river channels, some of which have been Climate zone 4.-Relatively little organic matter is added filled; point bar deposits; and abandoned meanders. The to the soils in this zone because conifer forest vegetation is surface generally is underlain by alluvial sand and gravel. In dominant and the understory vegetation is sparse. Also, places it is underlain by bedrock. Metallic artifacts in the cool temperatures slow the decomposition of organic alluvium indicate that formation of the surface probably matter. Examples of soils in this zone are those of the Hobit began after settlement of the valley of the Rogue River series (Typic Cryandepts) and those of the Otwin series (17). (Andic Cryochrepts). Accumulations of organic matter and weak grades of Soils in depressional areas where the water table is soil structure are the only morphological evidence of soil high support such vegetation as grasses and sedges formation in the Camas soils (Fluventic Haploxerolls) on rather than conifers or hardwoods. The decomposition of this surface. The content of organic matter in these soils this vegetation commonly results in soils that have a high irregularly decreases as depth increases, indicating that the content of organic matter and a thick mollic epipedon. parent material was recently deposited by water. Examples of such soils are those of the Klamath series Eagle Point surface. -This surface is on the higher of the (Cumulic Cryaquolls) and those of the Sibannac series two flood plains in the interior valley. It is between the (Cumulic Haplaquolls). TouVelle and Horseshoe surfaces. It formed during the late Holocene. The topography of the surface typically is Geomorphology characterized by undulating corrugations that have a maximum relief of about 6 feet. It is the result of the The major landforms in this survey area have been channeling that occurs when streams overflow their banks. divided into four physiographic provinces (fig. 19). These Flooding is common on this surface. provinces are areas that have had a similar geomorphic Horizon development in the soils on this surface is history and have similar geologic structures and limited to the accumulation of organic matter and the topographic relief, which are factors that greatly influence formation of a cambic horizon. The soils include Newberg soil genesis. The formation of the soils in one physiographic soils (Fluventic Haploxerolls), which formed in sandy province commonly is influenced by the geology of the alluvium, and Evans soils (Cumulic Haploxerolls), formed in other physiographic provinces. silty alluvium. In both of these soils, the content of organic matter irregularly decreases as depth increases. Evans soils Western Oregon Interior Valleys Province are higher on the landscape than Newberg soils and have a This province includes the interior valleys of the Rogue more strongly developed cambic horizon. and Applegate Rivers and their major tributaries. The main TouVelle surface. This surface is one of the most alluvial landforms are flood plains, terraces, and alluvial extensive geomorphic surfaces in the upper reaches of the fans. The soils in this province formed mainly in thick valleys of the Rogue River and Bear Creek. It consists alluvial deposits of various ages. mainly of alluvial terraces characterized by low relief and Late in the Pliocene, the climate in this survey area bar-and-channel topography. The surface layer of the soils became cooler and glaciers formed at the higher on this surface is mostly medium textured and is underlain elevations of the Cascade and Klamath Mountains. Much by sand and gravel. In some areas the soils have a thin material was eroded by the glaciers and carried downslope layer of ash from Mt. Mazama. by iceflow and meltwater (4). The material was then Radio-carbon dating of charcoal from a sycamore tree deposited, along with other rock material and silt, as (Platanus racemosa) recovered from a pumice flow along alluvium in the valleys of the major streams and formed the the upper reaches of the Rogue River indicates that the older of the present -day geomorphic surfaces. maximum age of the TouVelle surface is 6,930 years, plus The geomorphic surfaces in the valley of the upper or minus 115 years (17). Therefore, it is likely that the reaches of the Rogue River occur as a sequence of land surface formed during the early or middle Holocene. surfaces that reflects their geomorphic age and kind or The parent material is an important factor in the degree of profile development (fig. 20). These geomorphic formation of the soils on this geomorphic surface. The surfaces extend to the major tributaries of the Rogue source of the alluvial parent material is the volcanic rock of River. They are described in the following paragraphs. the Cascade Mountains or the metamorphic and granitic Horseshoe surface. This surface is on the lower of the rock of the Klamath Mountains. two flood plains along the Rogue and Applegate Rivers and along many of their tributaries. Flooding can Figure 19.-The physiographic provinces in the survey area.

The main kind of parent material on this surface is mixed rock in the Klamath Mountains. Examples of soils that alluvium that is coarse textured or fine textured. The soils formed in fine textured, mixed alluvium are those of the that formed in the coarse textured, mixed alluvium Medford series (Pachic Argixerolls) and those of the generally have a cambic horizon. An example is Central Foehlin series (Typic Argixerolls). These soils have an Point soils (Pachic Haploxerolls). The alluvial parent argillic horizon. Radio-carbon dating has indicated an age material of these soils weathered from granitic of 2,355 years (plus or minus 90 years) for a Figure 20.-Geomorphlc surfaces in the valley of the Rogue River and their related soil series.

partially mineralized Oregon white oak (Quercus garryanna) relict feature from a former period of soil formation (17). log that had been buried 2.7 meters under the TouVelle Kirtland surface.-Erosion of the older Roxy Ann surface surface. It can be assumed, therefore, that no more than and the development of an integrated surface drainage 2,000 to 3,000 years was required for the formation of an pattern resulted in the Kirtland surface. Areas of patterned argillic horizon (17). ground are characteristic of this surface. They are elongated Roxy Ann surface.-This surface is on an extensive fan and are parallel to the slope, in contrast to the circular soil terrace that makes up the main flood plain, known as the mounds and equant polygons of rock fragments "Agate Desert," in the valley of the Rogue River. characteristic of the adjacent Roxy Ann surface. The Topographical differences commonly are less than 3 feet. patterned ground common in areas of both the Kirtland and Circular areas of patterned ground are associated with this Roxy Ann surfaces suggests a nearly contemporaneous surface. The soils in these areas have a silica-cemented development, which probably occurred during periods of duripan containing rounded pebbles and cobbles. The extensive alpine glaciation in the Cascade Mountains. The surface drainage pattern is poorly expressed. No specimens next younger and lower surface, the TouVelle surface, has are available for radio-carbon dating of this surface. On the no patterned ground. Therefore, the Kirtland surface basis of the position of the soils on the landscape and their probably formed during the late Pleistocene (17). degree of weathering, however, the surface is estimated to Provig soils (Typic Argixerolls) are typical of the soils in be of late Pleistocene age (17). areas of this surface where the duripan that is typical of the Examples of the soils on this surface are those of the Roxy Ann surface has been truncated by an ancient erosion Agate series (Typic Durochrepts) and those of the Winlo cycle and an argillic horizon has subsequently formed. series (Typic Duraquolls). The contrast between the sizes of Where the Kirtland surface is characterized by moderate the particles in the solum and those in the duripan of these relief, areas of the Provig two soils indicates that the duripan is a soils are extensive. Agate soils, which have a duripan, are metamorphic rock structures commonly have been included in these areas (17). weakened because they are at a high angle and have been Hanley surface.-This surface is the oldest stable further weakened by faulting and shearing. Streams have geomorphic surface in the survey area. It is on dissected created a steep topography characterized by ridges that terraces and low foothills above the main valley floor. The generally are oriented from east to west. The stream soils are underlain by weathered gravel, clay, saprolite, or channels have high gradients and are narrow. bedrock (17). Because of the diversity of the parent The part of the Klamath Mountains in the survey area material, many different kinds of soil formed on this escaped the landform modifications resulting from glaciation surface. during the Pleistocene. Because of the periglacial The soils on this surface generally are well developed environment, however, the streams flowing out of the region because of its greater stability and relatively older age, from glaciated areas at the higher elevations were heavily which has allowed time for pedogenesis to take place. The loaded with sediment. Thick deposits of glaciofluvial soils have moderate or strong structure, are high in content material are on the high terraces in the area (4). of clay, or have an argillic horizon. Examples are Ruch soils A variety of soils formed in metasedimentary material, (Mollic Palexeralfs), which formed in mixed alluvium derived metavolcanic material, and material weathered from schist. from metamorphic rock of the Klamath Mountains; Wolfpeak In steep areas the soils are underlain by hard, relatively soils (Ultic Palexeralfs), which formed in alluvium derived unweathered bedrock. Erosion is active in many of these from granitic rock; and Carney soils (Typic Chromoxererts), areas (16). The soils that formed in these materials which formed in clayey alluvium and colluvium derived from commonly are moderately deep or shallow and are medium tuff and breccia of the Cascade Mountains (17). textured. Their mineralogy is mixed. Profile development Detailed geomorphic mapping at a larger scale would generally is limited to the formation of a cambic subsurface distinguish several more distinct landforms on this surface. horizon and an ochric epipedon. Steep, unstable topography For example, the geomorphic sequence mapped in the and the intense weathering that occurred as the soils aged upper reaches of the valley of the Rogue River also extends have resulted in the formation of Dystric and Typic into the lower reaches of the valley, into the part of the basin Xerochrepts. Examples of these are Kanid and Caris soils, of the Umpqua River that is in Oregon, and probably into respectively. Such soils as those of the Goolaway series California (17). (Dystric Xerochrepts) formed in material weathered from schist that is highly susceptible to water erosion. Klamath Mountains Province In many areas bedrock has been weathered to saprolite. The Klamath Mountains are complex areas The soils that formed in this material exhibit more evidence characterized by steep, rugged terrain. They are in a of profile development than the soils that formed in material region of ancient and highly altered rock formations. The weathered from hard bedrock. The soils that formed in rock that makes up the Klamath Mountains began forming colluvium are described as having a lithologic discontinuity in the Paleozoic and Triassic periods. Sediment, including in areas where they have hard rock fragments in the solum limestone-forming material and volcanic material, was and are underlain by soft bedrock. These soils are deposited on the floor of an inland sea. The sediment moderately sloping. Examples are Norling soils (Ultic subsequently was metamorphosed, altered by heat and Haploxeralfs) and Josephine soils (Typic Haploxerults). An pressure, folded and faulted, and then uplifted to form argillic horizon and hues that generally are redder than mountains. those of Ochrepts indicate that there has been a higher The metamorphic processes probably were associated degree of weathering. with an early phase of "sea-floor spreading," or plat e The northwestern part of the survey area has scattered tectonics (10). During the Jurassic and mid-Cretaceous intrusions of ultramafic rock, such as peridotite and periods, there was an episode of intrusion of granitic serpentine. The properties of the serpentinitic soils in this material into the overlying rock. During these periods area vary significantly; however, high base saturation, a emplacement of the Ashland Pluton and many other smaller predominance of magnesium as an exchangeable cation, granitic intrusions occurred throughout the Klamath and a low ratio of exchangeable calcium to magnesium are Mountains. The granitic bodies of the Blue Mountains and common features. Also, the soils have a low content of the Sierra Nevada also intruded at this time (10). Minor available phosphorus and potassium and a neutral reaction. intrusions of ultramafic rock, such as peridotite and Soils serpentinite, occurred earlier in the Triassic period. The intense geologic deformation of the Klamath Mountains commonly has weakened the rock. The that formed in material derived from ultramafic rock overlie nonmarine sandstone and siltstone sediment of the include those of the Dubakella series (Mollic upper Eocene age (21). The soils that formed in these Haploxeralfs) and those of the Gravecreek series materials are influenced by accumulations of alluvium and (Dystric Xerochrepts). colluvium of volcanic origin and in some areas are underlain by volcanic or sedimentary bedrock. Examples are Carney Western Cascade Province soils (Typic Chromoxererts) and Darow soils (Vertic There is an irregular boundary between the landforms Argixerolls) on stable landforms and Heppsie soils (Vertic on the western flank of the Cascade Mountains and the Haploxerolls) on steep, less stable landforms. younger volcanic landforms of the High Cascades. The Some of the soils formed solely in sedimentary Cascade Mountains are divided into two belts that trend parent material. They exhibit little evidence of profile north to south (4). The older, deformed rock is on the west development. Brader and Debenger soils (Typic flank of the Cascades, and the undistorted rock is on the Xerochrepts) are examples. High Cascades and the east flank of the Cascades. Fine textured Vertisols formed in basins and areas of low The western flank of the Cascades is made up of lava relief where clayey material accumulates. Examples are and pyroclastic rock ranging in age from Oligocene to late Kanutchan soils (Typic Pelloxererts) and Coker soils Miocene. During the Miocene the rock was uplifted, folded, (Chromic Pelloxererts). Coker soils also are in the Western faulted, affected by intruding shallow stocks, and then Oregon Interior Valleys Province, where they formed in deeply eroded. The rock dips to the east until it is overlain volcanic alluvial material. by more recent flows from shield volcanos of Pliocene to The younger strata characteristic of the Western recent age. Rock strata typically include beds of volcanic Cascade province mark its boundary with the High ash (tuff), large flows of andesite lava, and layers of Cascade province. The soils in this area are well developed andesitic breccia and agglomerate. (12). The landforms are in a youthful stage of development. The soils that formed in the Western Cascade province In some areas the drainageways are characterized by low were directly influenced by the weatherability of the parent relief. The bedrock commonly is hard. Examples of soils material. The strata of hard andesite and basalt include soft that formed in this area are those of the Pinehurst series breccia and tuffaceous rock. The soils in the areas of this (Pachic Ultic Argixerolls), which are deep and are on province that receive a greater amount of precipitation concave or linear landforms that are characterized by little commonly are Mollisols because of the interacting local relief, and those of the Farva series (Typic influences of the basic mineralogy of the volcanic parent Xerochrepts), which are moderately deep and formed on material and the accumulation of organic matter. Soils that convex slopes on hills and ridges. These soils formed in formed in material weathered from hard andesite and basalt, colluvium and have many hard rock fragments throughout such as McMullin soils (Lithic Ultic Haploxerolls), are the solum. shallow and medium textured. Other soils in this province not only formed in material High Cascade Province weathered from hard bedrock but also are influenced by The boundary between the western flank of the soft, easily weathered tuff and breccia. As a result, they are Cascades and the High Cascades is a separation based on fine textured and have an argillic horizon. Examples are age and general topography. Elevation ranges from about McNull soils (Ultic Argixerolls) and Tatouche soils (Typic 3,000 feet in the southeastern part of the survey area to Argixerolls). Soils that formed on concave slopes frequently about 6,600 feet on some of the higher peaks. are subject to increased weathering because of the The topography of the youthful High Cascades is concentration of water and the influence of easily weathered characteristically that of a broad upland plateau that has tuff and breccia. In some areas the concave slopes are the scattered volcanic cones. The landforms are easily result of gravitational mass movement of the regolith. These recognizable as their original forms because they have been soils commonly have a dense claypan that is very slowly only slightly modified by erosion. The topography is unlike permeable. Examples are Bybee soils (Typic Haploxerolls) that of the western flank of the Cascades, which is and Medco soils (Ultic Haploxerolls). characterized by deeply incised canyons and steeper slopes The oldest volcanic strata, on the western fringes and and by landforms that are almost entirely the result of foothills of the Cascades, are weathered andesite, tuff, erosion (32). and tuffaceous sedimentary rock. These strata The High Cascades began forming in the late Miocene with the extrusion of andesite and basalt (21). These flows, originating from shield volcanos and fissures, traveled long distances as intercanyon flows on fragments, the soils that form on the flow commonly contain both sides of the Cascades. On the western flank of the many hard to soft rock fragments. Woodcock soils (Argic Cascades, lava flows of the Pliocene and Pleistocene Pachic Cryoborolls), which have mixed mineralogy, became intercanyon flows within the drainageways of the probably formed in material derived from such a flow or in Rogue River and Big Butte Creek. The Table Rocks are glaciofluvial outwash consisting of volcanic material (4). remnants of these flows (32). On the eastern slope of the Other soils that contain many rock fragments are those of Cascades, flows entered the Klamath River Canyon area the Skookum series (Pachic Ultic Argixerolls), which formed and, at least once, created a barrier to the river. on flows and along the edges of flows and have a strongly Periodically, bouldery mudflows containing many rock expressed argillic horizon that has montmorillonitic fragments inundated the landscape. mineralogy. These soils are extensive in the southeastern In the recent Holocene, the explosive eruption of Mt. part of the survey area, above the Klamath River Canyon. Mazama, about 6,600 years ago, left a thick blanket of A unique kind of landform in this survey area is patterned pumice over some areas in the northeastern part of the ground (29), which is in nearly level areas of basaltic survey area. Other recent landforms are the cinder cones andesite flows. These areas have circular or elongated that are common in the southeastern part of the survey mounds that probably formed as a result of a combination area. They are made up of poorly consolidated ejecta of of environmental influences. The mounds are relict ash, cinders, scoria, and volcanic bombs (32). landforms that developed in areas of loess under the The soils in the High Cascades generally are in an early influence of the periglacial climate of the Pleistocene, about or intermediate stage of development because of the 8,000 years ago (4). The patterned ground occurs as a relative youth of the parent material and the cold climate. complex of Randcore and Shoat soils. Shoat soils (Typic Development of the solum has progressed enough in some Xerochrepts) are on the mounds, and the stony Randcore soils, however, for the formation of a cambic or argillic soils (poorly developed Lithic Xerorthents) are in areas horizon. The clay mineralogy of these soils varies, between the mounds. Both of these soils also are on the depending on the mineralogy of the parent rock and the Table Rocks in the Western Oregon Interior Valleys degree of weathering. province. The soils that formed in colluvium on hillslopes in areas The hillslopes and drainageways in the northern and of dissected flows and volcanic vents contain many rock central parts of the High Cascades are characterized by fragments. An example is Oatman soils (Dystric moderate relief. The soils that formed in these areas Cryochrepts), which has a cambic subsurface horizon. commonly are deep. The soils on convex landforms, such These soils are in the southeastern part of the survey as Coyata soils (Typic Xerumbrepts) and Geppert soils area. (Dystric Xerochrepts), have a high content of rock Several soils formed in material derived from mudflows fragments. The soils in concave and nearly level areas have or from other flows of pyroclastic material. These soils vary a low content of rock fragments. Examples are Dumont soils considerably in mineralogy. The soils that have halloysitic (Typic Haploxerults), which have kaolinitic mineralogy, and mineralogy are fine textured and are deep over bedrock. Freezener soils (Ultic Haploxeralfs). Because the landforms Examples are Hukill soils (Typic Rhodoxeralfs) and are stable, these soils have a well developed argillic Pokegema soils (Pachic Cryoborolls). These soils occur horizon. locally in some areas outside the High Cascade province as During the Pleistocene, volcanic activity resulted in a result of the extent of the intercanyon flows. andesite flows that covered most of the southern extension The soils that formed in material weathered from pumice of the High Cascades within the survey area. This latest and volcanic ash have low bulk density, are highly erodible, period of volcanism was contemporaneous with a period of and are minimally developed. Examples are Crater Lake faulting (13). The resulting faults are aligned from northeast and Alcot soils, both of which are Typic Vitrandepts. These to southwest. Several sets of cinder cones, including the soils formed in material that/was deposited in the Chicken Hills and Grenada Butte, are aligned parallel with northeastern part of the survey area during the eruption of the trend of this faulting. Mt. Mazama. During the same period, sandy material from Bench gravel along the Klamath River forms perched glacial activity in the Cascades was deposited in this area. terraces. These terraces may be remnants of a former Barhiskey soils (Entic Xerumbrepts), which formed in such lakebed that formed when the Klamath River was dammed material, show little evidence of profile development either through faulting or through volcanic eruption. During because of their young age. this period two maars formed near the Boyle Reservoir by When a flow of mud or debris has many rock eruption through these water-saturated gravel deposits (13). Toward the end of the Pleistocene, the area presently known as the Mountain Lakes Wilderness was soils that formed in this material include those of the covered by glaciers. Glacial outwash formed deposits that Aspenlake and Whiteface series (Duric Cryoborolls). are now preserved as perched terraces (13). The References

(1) American Association of State Highway and Transportation (11) Meyer, Walter H. 1961. Yield of even-aged stands of Officials. 1982. Standard specifications for highway ponderosa pine. U.S. Dep. Agric., Forest Service, Tech. materials and methods of sampling and testing. Ed. 13, 2 Bull. 630, 59 pp., illus. vols., illus. (12) Minore, Don. 1978. The Dead Indian Plateau. U.S. Dep. (2) American Society for Testing and Materials. 1988. Agric., Forest Serv., Gen. Tech. Rep. PNW-72, 23 pp., Standard test method for classification of soils for illus. engineering purposes. ASTM Stand. D 2487. (13) Naslund, Richard Howard. The geology of the Hyatt (3) Chambers, C.J. 1972. Empirical yield tables for the Reservoir and Surveyor Mountain Quadrangles, Oregon. Douglas fir zone. Washington Dep. Nat. Resour. Rep. Unpublished M.S. thesis completed in 1977 at the 20R, 16 pp., illus. University of Oregon, 127 pp., illus.

(4) Flint, Richard F. 1971. Glacial and Quaternary geology. (14) Oregon Agricultural College Experiment Station. 1920. John Wiley and Sons, Inc., pp. 243-516, illus. The soils of Jackson County. Exp. Stn. Bull. 164, 62 pp., illus. (5) Franklin, Jerry F. 1973. Natural vegetation of Oregon and Washington. U.S. Dep. Agric., Forest Serv., Gen. Tech. (15) Oregon State Department of Forestry. 1987-88. Rep. PNW-8, 416 pp., illus. Directory of Oregon forest products, market development program. 100 pp., illus. (6) Helfrich, Devere. 1966. Klamath echoes: Pokegama. Klamath Cty. Hist. Soc. Oregon 3, pp. 49-58, illus. (16) Parsons, Roger B., and Richard C. Herriman. 1975. A lithosequence in the mountains of southwestern (7) King, J.E. 1966. Site curves for Douglas fir in the Pacific Oregon. Soil Sci. Amer. J. 39: 943-948, illus. Northwest. Weyerhauser Forest. Pap. 8, 49 pp., illus. (17) Parsons, Roger B., and Richard C. Herriman. 1976. (8) Lalande, Jeffrey M. 1980. Prehistory and history of the Geomorphic surfaces and soil development in the Upper Rogue River National Forest: A cultural resource overview. Rogue Valley, Oregon. Soil Sci. Soc. Amer. J. 40: 933-938, U.S. Dep. Agric., Forest Serv., CR Job RR-280, 297 pp., illus. illus. (18) Portland Cement Association. 1962. PCA soil (9) McArdle, R.E., W.H. Meyer, and D. Bruce. 1961. The yield primer. 52 pp., illus. of Douglas fir in the Pacific Northwest. U.S. Dep. Agric., Forest Service, Tech. Bull. 201, 74 pp., illus. (19) Schumacher, F.X. 1926. Normal yield tables for red fir. California Agric. Exp. Stn. Bull. 456, 27 pp., illus. (10) McKee, Bates. 1972. Cascadia: The geologic evolution of the Pacific Northwest. McGraw-Hill, pp. 139-217, illus. (20) Schumacher, F.X. 1926. Normal yield tables for white fir. California Agric. Exp. Stn. Bull. 407, 26 pp., illus. (21) Smith, James G., and others. 1982. Preliminary geologic (27) Walling, A.G. 1884 (reprinted in 1970). History of map of the Medford Quadrangle, Oregon and California. southern Oregon. 545 pp., illus. USGS Open File Rep. 82-955. (28) Waring, R.H. 1969. Forest plants of the eastern (22) United States Department of Agriculture, Bureau of Soils. Siskiyous: Their environmental and vegetational 1913. Soil survey of the Medford area, Oregon. 74 pp., distribution. Northwest Sci. 43: 1-17, illus. illus. (29) Washburn, A.L. 1956. Classification of patterned ground (23) United States Department of Agriculture. 1951 (being and review of suggested origins. Geol. Soc. Amer. Bull. revised). Soil survey manual. U.S. Dep. Agric. Handb. 67: 823-866, illus. 18, 503 pp., illus. (30) Wells, F.G. 1956. Geologic map of the Medford (24) United States Department of Agriculture. 1961. Land Quadrangle, Oregon and California. USGS Surv. Map capability classification. U.S. Dep. Agric. Handb. 210, 21 GQ-89. pp. (31) Whittaker, R.H. 1960. Vegetation of the Siskiyou (25) United States Department of Agriculture. 1969. Interim soil Mountains, Oregon and California. Ecol. Monogr. 30: survey report, Jackson area, Oregon. 269 pp., illus. 279-338, illus.

(26) United States Department of Agriculture. 1975. Soil (32) Williams, Howel. 1976. The ancient volcanos of Oregon. taxonomy: A basic system of soil classification for Oregon State Syst. of Higher Educ., Condon Lect., 7th making and interpreting soil surveys. Soil Conserv. ed., 70 pp., illus. Serv., U.S. Dep. Agric. Handb. 436, 754 pp., illus. Glossary

Aeration, soil. The exchange of air in soil with air from the cation-exchange properties is saturated with atmosphere. The air in a well aerated soil is similar to exchangeable bases (sum of Ca, Mg, Na, K), that in the atmosphere; the air in a poorly aerated soil expressed as a percentage of the total cation- is considerably higher in carbon dioxide and lower in exchange capacity. oxygen. Basin. A depressional area that has few, if any, surface Aggregate, soil. Many fine particles held in a single mass drainage outlets. or cluster. Natural soil aggregates, such as granules, Bedding planes. Fine strata, less than 5 millimeters thick, blocks, or prisms, are called peds. Clods are in unconsolidated alluvial, eolian, lacustrine, or aggregates produced by tillage or logging. marine sediment. Alluvial fan. The fanlike deposit of a stream where it Bedrock. The solid rock that underlies the soil and other issues from a gorge upon a plain or of a tributary unconsolidated material or that is exposed at the stream near or at its junction with its main stream. surface. Alluvium. Material, such as sand, silt, or clay, Blowout. A shallow depression from which all or most of deposited on land by streams. the soil material has been removed by the wind. A Andesite. Fine grained, extrusive igneous rock that has a blowout has a flat or irregular floor formed by a composition between that of basalt and that of resistant layer or by an accumulation of pebbles or rhyolite. It generally has comparatively large crystals cobbles. In some blowouts the water table is exposed. in distinctly finer matrix material. Bottom land. The normal flood plain of a stream, Animal unit month (AUM). The amount of forage subject to flooding. required by one mature cow of approximately 1,000 Boulders. Rock fragments larger than 2 feet (60 pounds weight, with or without a calf, for 1 month. centimeters) in diameter. Area reclaim (in tables). An area difficult to reclaim after Breast height. An average height of 4.5 feet above the the removal of soil for construction and other uses. ground surface; the point on a tree where diameter Revegetation and erosion control are extremely measurements are ordinarily taken. difficult. Breccia. Coarse grained, clastic rock made up of Available water capacity (available moisture capacity). angular broken rock fragments held together by The capacity of soils to hold water available for use mineral cement or in a fine grained matrix. by most plants. It commonly is defined as the Brush management. Use of mechanical, chemical, or difference between the amount of water in the soil at biological methods to make conditions favorable for field moisture capacity and the amount at wilting reseeding or to reduce or eliminate competition from point. It commonly is expressed as inches of water woody vegetation and thus to allow understory per inch of soil. grasses and forbs to recover. Brush management Back slope. The geomorphic component that forms the increases forage production and thus reduces the steepest inclined surface and principal element of hazard of erosion. It can improve the habitat for some many hillsides. Back slopes in profile are commonly species of wildlife. steep, are linear, and may or may not include cliff Butte. An isolated small mountain or hill with steep or segments. precipitous sides and a top variously flat, rounded, or Basal area. The area of a cross section of a tree, generally pointed that may be a residual mass isolated by referring to the section at breast height and measured erosion or an exposed volcanic neck. outside the bark. It is a measure of stand density, Cable yarding. A method of moving felled trees to a commonly expressed in square feet. nearby central area for transport to a processing Base saturation. The degree to which material having facility. Most cable yarding systems involve use of a drum, a pole, and wire cables in an arrangement of a soil aggregate or lining pores or root similar to that of a rod and reel used for fishing. To channels. Synonyms: clay coating, clay skin. reduce friction and soil disturbance, felled trees Claypan. A slowly permeable soil horizon that contains generally are reeled in while one end is lifted or the much more clay than the horizons above it. A claypan entire log is suspended. is commonly hard when dry and plastic or stiff when Calcareous soil. A soil containing enough calcium wet. carbonate (commonly combined with magnesium Climax plant community. The plant community on a carbonate) to effervesce visibly when treated with given site that will be established if present cold, dilute hydrochloric acid. environmental conditions continue to prevail and California bearing ratio (CBR). The load-supporting the site is properly managed. capacity of a soil as compared to that of a standard Coarse fragments. Mineral or rock particles larger than 2 crushed limestone, expressed as a ratio. First millimeters in diameter. standardized in California. A soil having a CBR of 16 Coarse textured soil. Sand or loamy sand. supports 16 percent of the load that would be Cobble (or cobblestone). A rounded or partly rounded supported by standard crushed limestone, per unit fragment of rock 3 to 10 inches (7.6 to 25 area, with the same degree of distortion. centimeters) in diameter. Canopy. The leafy crown of trees or shrubs. (See Cobbly soil material. Material that is 15 to 35 percent, by Crown.) volume, rounded or partially rounded rock fragments Canyon. A long, deep, narrow, very steep sided valley with 3 to 10 inches (7.6 to 25 centimeters) in diameter. high, precipitous walls in an area of high local relief. Very cobbly soil material is 35 to 60 percent of these Capillary water. Water held as a film around soil rock fragments, and extremely cobbly soil material is particles and in tiny spaces between particles. more than 60 percent. Surface tension is the adhesive force that holds Colluvium. Soil material, rock fragments, or both, capillary water in the soil. moved by creep, slide, or local wash and Cation. An ion carrying a positive charge of electricity. deposited at the base of steep slopes. The common soil cations are calcium, potassium, Complex, soil. A map unit of two or more kinds of soil or magnesium, sodium, and hydrogen. miscellaneous areas in such an intricate pattern or so Cation-exchange capacity. The total amount of small in area that it is not practical to map them exchangeable cations that can be held by the soil, separately at the selected scale of mapping. The expressed in terms of milliequivalents per 100 grams pattern and proportion of the soils or miscellaneous of soil at neutrality (pH 7.0) or at some other stated areas are somewhat similar in all areas. pH value. The term, as applied to soils, is Concretions. Grains, pellets, or nodules of various sizes, synonymous with base-exchange capacity but is shapes, and colors consisting of concentrated more precise in meaning. compounds or cemented soil grains. The composition Channery soil. A soil that is, by volume, more than 15 of most concretions is unlike that of the surrounding percent thin, flat fragments of sandstone, shale, soil. Calcium carbonate and iron oxide are common slate, limestone, or schist as much as 6 inches along compounds in concretions. the longest axis. A single piece is called a channer. Conservation cropping system. Growing crops in Chemical treatment. Control of unwanted vegetation combination with needed cultural and management through the use of chemicals. practices. In a good conservation cropping system, Chiseling. Tillage with an implement having one or more soil-improving crops and practices more than offset soil-penetrating points that loosen the subsoil and the soil-depleting crops and practices. Cropping bring clods to the surface. A form of emergency tillage systems are needed on all tilled soils. Soil-improving to control soil blowing. practices in a conservation cropping system include Clay. As a soil separate, the mineral soil particles less than the use of rotations that contain grasses and legumes 0.002 millimeter in diameter. As a soil textural class, and the return of crop residue to the soil. Other soil material that is 40 percent or more clay, less than practices include the use of green manure crops of 45 percent sand, and less than 40 percent silt. grasses and legumes, proper tillage, adequate Clay film. A thin coating of oriented clay on the surface fertilization, and weed and pest control. Consistence, soil. The feel of the soil and the ease with which a lump can be crushed by the fingers. Terms commonly used to describe consistence are: is called the culmination of the mean annual Loose.-Noncoherent when dry or moist; does not hold increment. together in a mass. Cutbanks cave (in tables). The walls of excavations Friable.-When moist, crushes easily under gentle tend to cave in or slough. pressure between thumb and forefinger and can be Decreasers. The most heavily grazed climax range plants. pressed together into a lump. Because they are the most palatable, they are the Firm.-When moist, crushes under moderate pressure first to be destroyed by overgrazing. between thumb and forefinger, but resistance is Deferred grazing. Postponing grazing or resting grazing distinctly noticeable. land for a prescribed period. Plastic.-Readily deformed by moderate pressure but Delta. A body of alluvium having a surface that is nearly flat can be pressed into a lump; will form a "wire" when and fan shaped, deposited at or near the mouth of a rolled between thumb and forefinger. river or stream where it enters a body of relatively Sticky. -Adheres to other material and tends to stretch quiet water, generally a sea or lake. somewhat and pull apart rather than to pull free from Depth to rock (in tables). Bedrock is too near the other material. surface for the specified use. Hard.-When dry, moderately resistant to pressure; Diversion (or diversion terrace). A ridge of earth, can be broken with difficulty between thumb and generally a terrace, built to protect downslope forefinger. areas by diverting runoff from its natural course. Soft.-When dry , breaks into powder or individual Drainage class (natural). Refers to the frequency and grains under very slight pressure. duration of periods of saturation or partial saturation Cemented.-Hard; little affected by moistening. during soil formation, as opposed to altered drainage, Control section. The part of the soil on which classification which is commonly the result of artificial drainage or is based. The thickness varies among different kinds irrigation but may be caused by the sudden deepening of soil, but for many it is that part of the soil profile of channels or the blocking of drainage outlets. Seven between depths of 10 inches and 40 or 80 inches. classes of natural soil drainage are recognized: Corrosive. High risk of corrosion to uncoated steel or Excessively drained.- These soils have very high and deterioration of concrete. high hydraulic conductivity and a low water-holding Cover crop. A close-growing crop grown primarily to capacity. They are not suited to crop production unless improve and protect the soil between periods of irrigated. regular crop production, or a crop grown between Somewhat excessively drained.-These soils have high trees and vines in orchards and vineyards. hydraulic conductivity and a low water-holding Cropping system. Growing crops according to a capacity. Without irrigation, only a narrow range of planned system of rotation and management crops can be grown and yields are low. practices. Well drained. -These soils have an intermediate Crop residue management. Returning crop residue to water-holding capacity. They retain optimum amounts the soil, which helps to maintain soil structure, of moisture, but they are not wet close enough to the organic matter content, and fertility and helps to surface or long enough during the growing season to control erosion. adversely affect yields. Cross-slope farming. Deliberately conducting farming Moderately well drained.-These soils are wet close operations on sloping farmland in such a way that enough to the surface or long enough that planting or tillage is across the general slope. harvesting operations or yields of some field crops are Crown. The upper part of a tree or shrub, including the adversely affected unless a drainage system is living branches and their foliage. installed. Moderately well drained soils commonly Culmination of the mean annual increment (CMAI). have a layer with low hydraulic conductivity, a wet The average annual increase per acre in the volume layer relatively high in the profile, additions of water by of a stand. Computed by dividing the total volume of seepage, or some combination of these. the stand by its age. As the stand increases in age, Somewhat poorly drained.-These soils are wet close the mean annual increment continues to increase enough to the surface or long enough that planting or until mortality begins to reduce the rate of increase. harvesting operations or crop growth is markedly The point where the stand reaches its maximum restricted unless a drainage system is installed. annual rate of growth Somewhat poorly drained soils commonly have a layer with low hydraulic Escarpment. A relatively continuous and steep slope or cliff conductivity, a wet layer high in the profile, additions breaking the general continuity of more gently sloping of water through seepage, or a combination of these. land surfaces and resulting from erosion or faulting. Poorly drained.- These soils commonly are so wet at Synonym: scarp. or near the surface during a considerable part of the Excess fines (in tables). Excess silt and clay in the soil. year that field crops cannot be grown under natural The soil does not provide a source of gravel or sand conditions. Poorly drained conditions are caused by a for construction purposes. saturated zone, a layer with low hydraulic Extrusive rock. Igneous rock derived from deep-seated conductivity, seepage, or a combination of these. molten matter (magma) emplaced on the earth's Very poorly drained.-These soils are wet to the surface. surface most of the time. The wetness prevents the Fallow. Cropland left idle in order to restore productivity growth of important crops (except for rice) unless a through accumulation of moisture. Summer fallow is drainage system is installed. common in regions of limited rainfall where cereal Drainage, surface. Runoff, or surface flow of water, grain is grown. The soil is tilled for at least one from an area. growing season for weed control and decomposition Duff. A generally firm organic layer on the surface of of plant residue. mineral soils. It consists of fallen plant material that is Fan terrace. A relict alluvial fan, no longer a site of in the process of decomposition and includes active deposition, incised by younger and lower everything from the litter on the surface to underlying alluvial surfaces. pure humus. Fast intake (in tables). The rapid movement of water Duripan. A subsurface horizon that is cemented by silica to into the soil. the degree that fragments from an air-dried sample Fertility, soil. The quality that enables a soil to provide do not slake in water or hydrochloric acid. A duripan plant nutrients, in adequate amounts and in proper is very firm or extremely firm when moist and is brittle. balance, for the growth of specified plants when light, Eluviation. The movement of material in true solution or moisture, temperature, tilth, and other growth factors colloidal suspension from one place to another within are favorable. the soil. Soil horizons that have lost material through Field moisture capacity. The moisture content of a soil, eluviation are eluvial; those that have received expressed as a percentage of the ovendry weight, material are illuvial. after the gravitational, or free, water has drained Eolian soil material. Earthy parent material accumulated away; the field moisture content 2 or 3 days after a through wind action; commonly refers to sandy soaking rain; also called normal field capacity, normal material in dunes or to loess in blankets on the moisture capacity, or capillary capacity. surface. Fill slope. A sloping surface consisting of excavated soil Ephemeral stream. A stream, or reach of a stream, that material from a road cut. It commonly is on the flows only in direct response to precipitation. It downhill side of the road. receives no long-continued supply from melting snow Fine textured soil. Sandy clay, silty clay, or clay. or other source, and its channel is above the water Firebreak. Area cleared of flammable material to stop or table at all times. help control creeping or running fires. It also serves Erosion. The wearing away of the land surface by water, as a line from which to work and to facilitate the wind, ice, or other geologic agents and by such movement of firefighters and equipment. processes as gravitational creep. Designated roads also serve as firebreaks. Erosion (geologic). Erosion caused by geologic Flood plain. A nearly level alluvial plain that borders a processes acting over long geologic periods and stream and is subject to flooding unless protected resulting in the wearing away of mountains and the artificially. building up of such landscape features as flood plains Fluvial. Of or pertaining to rivers; produced by river and coastal plains. Synonym: natural erosion. action, as a fluvial plain. Erosion (accelerated). Erosion much more rapid than Foothill. A steeply sloping upland that has relief of as geologic erosion, mainly as a result of human or much as 1,000 feet (or 300 meters) and fringes a animal activities or of a catastrophe in nature, such as mountain range or high-plateau escarpment. a fire, that exposes the surface. Foot slope. The inclined surface at the base of a hill. Forb. Any herbaceous plant not a grass or a sedge. Forest cover. All trees and other woody plants (underbrush) covering the ground in a forest. Forest type. A stand of trees similar in composition and depth and can be smoothed over by ordinary development because of given physical and biological tillage. factors by which it may be differentiated from other Hard bedrock. Bedrock that cannot be excavated stands. except by blasting or by the use of special Frost action (in tables). Freezing and thawing of soil equipment that is not commonly used in moisture. Frost action can damage roads, construction. buildings and other structures, and plant roots. Hardpan. A hardened or cemented soil horizon, or layer. Gabbro. Dark, coarse grained basic igneous rock that is the The soil material is sandy, loamy, or clayey and is approximate intrusive equivalent of basalt. cemented by iron oxide, silica, calcium carbonate, or Genesis, soil. The mode of origin of the soil. Refers other substance. especially to the processes or soil-forming factors High-residue crops. Such crops as small grain and corn responsible for the formation of the solum, or true used for grain. If properly managed, residue from soil, from the unconsolidated parent material. these crops can be used to control erosion until the Glacial outwash (geology). Gravel, sand, and silt, next crop in the rotation is established. These crops commonly stratified, deposited by glacial return large amounts of organic matter to the soil. meltwater. Hill. A natural elevation of the land surface, rising as Glaciofluvial deposits (geology). Material moved by much as 1,000 feet above surrounding lowlands, glaciers and subsequently sorted and deposited by commonly of limited summit area and having a well streams flowing from the melting ice. The deposits are defined outline; hillsides generally have slopes of stratified and occur as kames, eskers, deltas, and more than 15 percent. The distinction between a hill outwash plains. and a mountain is arbitrary and is dependent on Glaciolacustrine deposits. Material ranging from fine local usage. clay to sand derived from glaciers and deposited in Hillslope. The steep part of a hill between its summit and glacial lakes mainly by glacial meltwater. Many the drainage line, valley flat, or depression floor at the deposits are interbedded or laminated. base of the hill. In descending order, the components Gleyed soil. Soil that formed under poor drainage, of a simple hillslope may include a shoulder slope, a resulting in the reduction of iron and other back slope, a foot slope, and a toe slope. Not all of elements in the profile and in gray colors and these components, however, are necessarily evident mottles. in any given hillslope continuum. Complex hillslopes Granodiorite. Granitic rock of intermediate composition may include two or more sequences of back slopes or between that of granite and that of diorite. toe slopes. Grassed waterway. A natural or constructed waterway, Horizon, soil. A layer of soil, approximately parallel to the typically broad and shallow, seeded to grass as surface, having distinct characteristics produced by protection against erosion. Conducts surface water soil-forming processes. In the identification of soil away from cropland. horizons, an uppercase letter represents the major Gravel. Rounded or angular fragments of rock as much as horizons. Numbers or lowercase letters that follow 3 inches (2 millimeters to 7.6 centimeters) in represent subdivisions of the major horizons. An diameter. An individual piece is a pebble. explanation of the subdivisions is given in the "Soil Gravelly soil material. Material that is more than 15 Survey Manual." The major horizons of mineral soil percent, by volume, rounded or angular rock are as follows: fragments, not prominently flattened, as much as 3 O horizon. - An organic layer of fresh and decaying inches (7.6 centimeters) in diameter. plant residue. Green manure crop (agronomy). A soil-improving crop A horizon.-The mineral horizon at or near the surface grown to be plowed under in an early stage of in which an accumulation of humified organic matter is maturity or soon after maturity. mixed with the mineral material. Also, a plowed Ground water (geology). Water filling all the unblocked surface horizon, most of which was originally part of a pores of underlying material below the water table. B horizon. Gully. A miniature valley with steep sides cut by running E horizon.-The mineral horizon in which the main water and through which water ordinarily runs only feature is loss of silicate clay, iron, aluminum, or some after rainfall. The distinction between a gully and a rill combination of these. is one of depth. A gully generally is an obstacle to B horizon.-The mineral horizon below an A horizon. farm machinery and is too deep to be obliterated by The B horizon is in part a layer of ordinary tillage; a rill is of lesser transition from the overlying A to the underlying C Therefore, intake rate for design purposes is not a horizon. The B horizon also has distinctive constant but is a variable depending on the net characteristics, such as (1) accumulation of clay, irrigation application. The rate of water intake, in sesquioxides, humus, or a combination of these; (2) inches per hour, is expressed as follows: prismatic or blocky structure; (3) redder or browner colors than those in the A horizon; or (4) a Less than 0.2 ...... very low combination of these. 0.2 to 0.4...... low 0.4 to 0.75...... moderately low C horizon.-The mineral horizon or layer, excluding 0.75 to 1.25...... moderate indurated bedrock, that is little affected by 1.25 to 1.75...... moderately high soil-forming processes and does not have the 1.75 to 2.5...... high properties typical of the overlying soil material. The More than 2.5 ...... very high material of a C horizon may be either like or unlike that in which the solum formed. If the material is Intermittent stream. A stream, or reach of a stream, that known to differ from that in the solum, an Arabic flows for prolonged periods only when it receives numeral, commonly a 2, precedes the letter C. ground-water discharge or long, continued Cr horizon.-Soft, consolidated bedrock beneath the contributions from melting snow or other surface and soil. shallow subsurface sources. R layer.-Consolidated bedrock beneath the soil. The Invaders. On range, plants that encroach into an area bedrock commonly underlies a C horizon, but it can and grow after the climax vegetation has been be directly below an A or a B horizon. reduced by grazing. Generally, plants invade Humus. The well decomposed, more or less stable part of following disturbance of the surface. the organic matter in mineral soils. Irrigation. Application of water to soils to assist in Igneous rock. Rock formed by solidification from a production of crops. Methods of irrigation are: molten or partially molten state. Major varieties Basin. -Water is applied rapidly to nearly level plains include plutonic and volcanic rock. Examples are surrounded by levees or dikes. andesite, basalt, and granite. Border.-Water is applied at the upper end of a strip in Illuviation. The movement of soil material from one which the lateral flow of water is controlled by small horizon to another in the soil profile. Generally, earth ridges called border dikes, or borders. material is removed from an upper horizon and Contour flood.-All necessary water-control structures deposited in a lower horizon. are installed for the efficient distribution of water by Impervious soil. A soil through which water, air, or roots surface means, such as contour ditches. penetrate slowly or not at all. No soil is absolutely Controlled flooding. -Water is released at intervals impervious to air and water all the time. from closely spaced field ditches and distributed Increasers. Species in the climax vegetation that uniformly over the field. increase in amount as the more desirable plants Corrugation.-Water is applied to small, closely spaced are reduced by close grazing. Increasers furrows or ditches in fields of close-growing crops or commonly are the shorter plants and the less in orchards so that it flows in only one direction. palatable to livestock. Drip (or trickle).-Water is applied slowly and under low Infiltration. The downward entry of water into the pressure to the surface of the soil or into the soil immediate surface of soil or other material, as through such applicators as emitters, porous tubing, contrasted with percolation, which is movement of or perforated pipe. water through soil layers or material. Furrow.-Water is applied in small ditches made by Infiltration capacity. The maximum rate at which water cultivation implements. Furrows are used for tree and can infiltrate into a soil under a given set of row crops. conditions. Sprinkler.-Water is sprayed over the soil surface Infiltration rate. The rate at which water penetrates the through pipes or nozzles from a pressure system. surface of the soil at any given instant, usually Subirrigation.-Water is applied in open ditches or tile expressed in inches per hour. The rate can be limited lines until the water table is raised enough to wet the by the infiltration capacity of the soil or the rate at soil. which water is applied at the surface. Knoll. A small, low, rounded hill rising above adjacent Intake rate . The average rate of water entering the soil landforms. under irrigation. Most soils have a fast initial rate; the Lacustrine deposit (geology). Material deposited in rate decreases with application time. lake water and exposed when the water level is Moderately fine textured soil. Clay loam, sandy clay lowered or the elevation of the land is raised. loam, or silty clay loam. Landslide . The rapid downhill movement of a mass of Morphology, soil. The physical makeup of the soil, soil and loose rock, generally when wet or including the texture, structure, porosity, saturated. The speed and distance of movement, as consistence, color, and other physical, mineral, and well as the amount of soil and rock material, vary biological properties of the various horizons, and greatly. the thickness and arrangement of those horizons in Large stones (in tables). Rock fragments 3 inches (7.6 the soil profile. centimeters) or more across. Large stones adversely Mottling, soil. Irregular spots of different colors that vary in affect the specified use of the soil. number and size. Mottling generally indicates poor Leaching. The removal of soluble material from soil or aeration and impeded drainage. Descriptive terms are other material by percolating water. as follows: abundance-few, common, and many; Light textured soil. Sand or loamy sand. size-fine, medium, and coarse; and contrast-faint, Liquid limit. The moisture content at which the soil distinct, and prominent. The size measurements are passes from a plastic to a liquid state. of the diameter along the greatest dimension. Fine Loam. Soil material that is 7 to 27 percent clay particles, indicates less than 5 millimeters (about 0.2 inch); 28 to 50 percent silt particles, and less than 52 medium, from 5 to 15 millimeters (about 0.2 to 0.6 percent sand particles. inch); and coarse, more than 15 millimeters (about 0.6 Loess. Fine grained material, dominantly of silt-sized inch). particles, deposited by wind. Mountain. A natural elevation of the land surface, rising Low -residue crops. Such crops as corn used for silage, more than 1,000 feet above surrounding lowlands, peas, beans, and potatoes. Residue from these crops commonly of restricted summit area (relative to a is not adequate to control erosion until the next crop in plateau) and generally having steep sides and the rotation is established. These crops return little considerable bare-rock surface. A mountain can occur organic matter to the soil. as a single, isolated mass or in a group forming a Low strength. The soil is not strong enough to support chain or range. loads. Mudstone. Sedimentary rock formed by induration of silt Maar. A broad, low-relief volcanic crater formed by and clay in approximately equal amounts. multiple, shallow, explosive eruptions. It is Munsell notation. A designation of color by degrees of surrounded by a crater ring and may be filled with three simple variables-hue, value, and chroma. For water. example, a notation of 10YR 6/4 is a color with hue of Mechanical treatment. Use of mechanical equipment 10YR, value of 6, and chroma of 4. for seeding, brush management, and other Neutral soil. A soil having a pH value between 6.6 and management practices. 7.3. (See Reaction, soil.) Medium textured soil. Very fine sandy loam, loam, silt Nutrient, plant. Any element taken in by a plant essential loam, or silt. to its growth. Plant nutrients are mainly nitrogen, Metamorphic rock. Rock of any origin altered in phosphorus, potassium, calcium, magnesium, sulfur, mineralogical composition, chemical composition, or iron, manganese, copper, boron, and zinc obtained structure by heat, pressure, and movement. Nearly from the soil and carbon, hydrogen, and oxygen all such rocks are crystalline. obtained from the air and water. Metavolcanic rock. One of a wide variety of volcanic Outwash plain. A landform of mainly sandy or coarse rocks that have been subject to metamorphic textured material of glaciofluvial origin. An outwash processes. The degree of metamorphic alteration is plain is commonly smooth; where pitted, it generally is not implied by the term. low in relief. Mineral soil. Soil that is mainly mineral material and Pan. A compact, dense layer in a soil that impedes the low in organic material. Its bulk density is more movement of water and the growth of roots. For than that of organic soil. example, hardpan, fragipan, claypan, plowpan, and Minimum tillage. Only the tillage essential to crop traffic pan. production and prevention of soil damage. Parent material. The unconsolidated organic and Miscellaneous area. An area that has little or no mineral material in which soil forms. natural soil and supports little or no vegetation. Patterned ground. More or less symmetrical landforms, Moderately coarse textured soil. Coarse sandy loam, such as circles, polygons, nets, stripes, and sandy loam, or fine sandy loam. garlands, that are characteristic of, but not confined to, of the particles, density can be increased only mantles subject to intense frost action, such as that in slightly by compaction. periglacial environments. Potential native plant community. See Climax plant Ped. An individual natural soil aggregate, such as a community. granule, a prism, or a block. Prescribed burning. The application of fire to land Pedon. The smallest volume that can be called "a soil." A under such conditions of weather, soil moisture, pedon is three dimensional and large enough to and time of day as presumably results in the permit study of all horizons. Its area ranges from intensity of heat and spread required to accomplish about 10 to 100 square feet (1 square meter to 10 specific forest management, wildlife, grazing, or fire square meters), depending on the variability of the hazard reduction purposes. soil. Productivity, soil. The capability of a soil for producing a Percolation. The downward movement of water through specified plant or sequence of plants under specific the soil. management. Percs slowly (in tables). The slow movement of water Profile, soil. A vertical section of the soil extending through the soil, adversely affecting the specified through all its horizons and into the parent use. material. Permeability. The quality of the soil that enables water to Proper grazing use. Grazing at an intensity that maintains move downward through the profile. Permeability is enough cover to protect the soil and maintain or measured as the number of inches per hour that improve the quantity and quality of the desirable water moves downward through the saturated soil. vegetation. This practice increases the vigor and Terms describing permeability are: reproduction capacity of the key plants and promotes the accumulation of litter and mulch necessary to Very slow ...... less than 0.06 inch conserve soil and water. Slow...... 0.06 to 0.2 inch Puddling. Compaction of a soil during wet periods to the Moderately slow ...... 0.2 to 0.6 inch Moderate ...... 0.6 inch to 2.0 inches point that the soil particles are rearranged to a Moderately rapid ...... 2.0 to 6.0 inches massive state. Rapid ...... 6.0 to 20 inches Pumice. A light colored, vesicular, glassy rock fragment of Very rapid ...... more than 20 inches volcanic origin. It has enough buoyancy to float on Piping (in tables). Formation of subsurface tunnels or water. pipelike cavities by water moving through the soil. Reaction, soil. A measure of acidity or alkalinity of a soil, Plasticity index. The numerical difference between the expressed in pH values. A soil that tests to pH 7.0 is liquid limit and the plastic limit; the range of moisture described as precisely neutral in reaction because it is content within which the soil remains plastic. neither acid nor alkaline. The degrees of acidity or Plastic limit. The moisture content at which a soil alkalinity, expressed as pH values, are: changes from semisolid to plastic. Extremely acid ...... below 4.5 Plateau. An extensive upland mass with a relatively flat Very strongly acid ...... 4.5 to 5.0 summit area that is considerably elevated (more than Strongly acid ...... 5.1 to 5.5 100 meters) above adjacent lowlands and separated Moderately acid ...... 5.6 to 6.0 Slightly acid ...... 6.1 to 6.5 from them on one or more sides by escarpments. Neutral ...... 6.6 to 7.3 Plowpan. A compacted layer formed in the soil directly Mildly alkaline ...... 7.4 to 7.8 below the plowed layer. Moderately alkaline ...... 7.9 to 8.4 Ponding. Standing water on soils in closed Strongly alkaline ...... 8.5 to 9.0 depressions. Unless the soils are artificially Very strongly alkaline ...... 9.1 and higher drained, the water can be removed only by Relief. The elevations or inequalities of a land surface, percolation or evapotranspiration. considered collectively. Poor filter (in tables). Because of rapid permeability or an Residuum (residual soil material). Unconsolidated, impermeable layer near the surface, the soil may not weathered or partly weathered mineral material adequately filter effluent from a waste disposal that accumulated as consolidated rock system. disintegrated in place. Poorly graded. Refers to a coarse grained soil or soil Rill. A steep-sided channel resulting from accelerated material consisting mainly of particles of nearly the erosion. A rill generally is a few inches deep and not same size. Because there is little difference in size wide enough to be an obstacle to farm machinery. Road cut. A sloping surface produced by mechanical Shale. Sedimentary rock formed by the hardening of a means during road construction. It is commonly on clay deposit. the uphill side of the road. Sheet erosion. The removal of a fairly uniform layer of soil Rock fragments. Rock or mineral fragments having a material from the land surface by the action of rainfall diameter of 2 millimeters or more; for example, or surface runoff. pebbles, cobbles, stones, and boulders. Shrink-swell (in tables). The shrinking of soil when dry and Rooting depth (in tables). Shallow root zone. The soil is the swelling when wet. Shrinking and swelling can shallow over a layer that greatly restricts roots. damage roads, dams, building foundations, and other Root zone. The part of the soil that can be penetrated by structures. It can also damage plant roots. plant roots. Silica. A combination of silicon and oxygen. The Runoff. The precipitation discharged into stream channels mineral form is called quartz. from an area. The water that flows off the surface of Silica -sesquioxide ratio. The ratio of the number of the land without sinking into the soil is called surface molecules of silica to the number of molecules of runoff. Water that enters the soil before reaching alumina and iron oxide. The more highly weathered surface streams is called groundwater runoff or soils or their clay fractions in warm-temperate, humid seepage flow from ground water. regions, and especially those in the tropics, generally Sand. As a soil separate, individual rock or mineral have a low ratio. fragments from 0.05 millimeter to 2.0 millimeters in Silt. As a soil separate, individual mineral particles that diameter. Most sand grains consist of quartz. As a soil range in diameter from the upper limit of clay (0.002 textural class, a soil that is 85 percent or more sand millimeter) to the lower limit of very fine sand (0.05 and not more than 10 percent clay. millimeter). As a soil textural class, soil that is 80 Sandstone. Sedimentary rock containing dominantly percent or more silt and less than 12 percent clay. sand-sized particles. Siltstone. Sedimentary rock made up of dominantly silt- Saprolite (soil science). Unconsolidated residual sized particles. material underlying the soil and grading to hard Site class. A grouping of site indexes into five to seven bedrock below. production capability levels. Each level can be Schist. Metavolcanic rock that has been largely or represented by a site curve. completely recrystallized and exhibits strong parallel Site curve (50-year). A set of related curves on a graph or planar arrangement of platy or prismatic mineral that shows the average height of dominant trees for grains. It can readily split into thin plates or slabs. the range of ages on soils that differ in productivity. Sedimentary rock. Rock made up of particles deposited Each level is represented by a curve. The basis of the from suspension in water. The chief kinds of curves is the height of dominant trees that are 50 sedimentary rock are conglomerate, formed from years old or are 50 years old at breast height. gravel; sandstone, formed from sand; shale, formed Site curve (100-year). A set of related curves on a graph from clay; and limestone, formed from soft masses of that shows the average height of dominant and calcium carbonate. There are many intermediate codominant trees for a range of ages on soils that types. Some wind-deposited sand is consolidated into differ in productivity. Each level is represented by a sandstone. curve. The basis of the curves is the height of Seepage (in tables). The movement of water through the dominant and codominant trees that are 100 years old soil. Seepage adversely affects the specified use. or are 100 years old at breast height. Series, soil. A group of soils that have profiles that are Site index. A designation of the quality of a forest site almost alike, except for differences in texture of the based on the height of the dominant stand at an surface layer or of the substratum. All the soils of a arbitrarily chosen age. For example, if the average series have horizons that are similar in composition, height attained by dominant and codominant trees in a thickness, and arrangement. fully stocked stand at the age of 50 years is 75 feet, Serpentine. A greenish, greenish yellow, or greenish gray the site index is 75. rock that has a greasy or silky luster and a tough, Skid trail. A trail or furrow made by a log or logs conchoidal fracture. It formed as an alteration product skidding over the ground surface. from magnesium-rich silicate minerals and is evident Slickensides. Polished and grooved surfaces produced by in igneous or metamorphic rock. one mass sliding past another. In soils, slickensides may occur at the bases of slip surfaces inches (15 to 38 centimeters) in length if flat. on the steeper slopes; on faces of blocks, prisms, and Stony. Refers to a soil containing stones in numbers columns; and in swelling clayey soils, where there is that interfere with or prevent tillage. marked change in moisture content. Stripcropping. Growing crops in a systematic Slope. The inclination of the land surface from the arrangement of strips or bands that provide horizontal. Percentage of slope is the vertical vegetative barriers to soil blowing and water distance divided by horizontal distance, then erosion. multiplied by 100. Thus, a slope of 20 percent is a Structure, soil. The arrangement of primary soil particles drop of 20 feet in 100 feet of horizontal distance. into compound particles or aggregates. The principal Slope (in tables). Slope is great enough that special forms of soil structure are-platy (laminated), prismatic practices are required to ensure satisfactory (vertical axis of aggregates longer than horizontal), performance of the soil for a specific use. columnar (prisms with rounded tops), blocky (angular Slow intake (in tables). The slow movement of water or subangular), and granular. Structureless soils are into the soil. either single grain (each grain by itself, as in dune Small stones (in tables). Rock fragments less than 3 sand) or massive (the particles adhering without any inches (7.6 centimeters) in diameter. Small stones regular cleavage, as in many hardpans). adversely affect the specified use of the soil. Stubble mulch. Stubble or other crop residue left on the Soft bedrock. Bedrock that can be excavated with soil or partly worked into the soil. It protects the soil trenching machines, backhoes, small rippers, and from soil blowing and water erosion after harvest, other equipment commonly used in construction. during preparation of a seedbed for the next crop, Soil. A natural, three-dimensional body at the earth's and during the early growing period of the new crop. surface. It is capable of supporting plants and has Subsoil. Technically, the B horizon; roughly, the part of the properties resulting from the integrated effect of solum below plow depth. climate and living matter acting on earthy parent Subsoiling. Tilling a soil below normal plow depth, material, as conditioned by relief over periods of time. ordinarily to shatter a hardpan or claypan. Soil separates. Mineral particles less than 2 millimeters in Substratum. The part of the soil below the solum. equivalent diameter and ranging between specified Subsurface layer. Technically, the E horizon. Generally size limits. The names and sizes, in millimeters, of refers to a leached horizon lighter in color and lower in separates recognized in the United content of organic matter than the overlying surface States are as follows: layer.

Very coarse sand ...... 2.0 to 1.0 Summer fallow. The tillage of uncropped land during the

Coarse sand...... 1.0 to 0.5 summer to control weeds and allow storage of Medium sand...... 0.5 to 0.25 moisture in the soil for the growth of a later crop. A Fine sand ...... 0.25 to 0.1 0 practice common in semiarid regions, where annual Very fine sand...... 0.10 to 0.05 precipitation is not enough to produce a crop every Silt ...... 05 to 0.002 year. Summer fallow is frequently practiced before Clay ...... less than 0.002 planting winter grain. Solum. The upper part of a soil profile, above the C Surface layer. The soil ordinarily moved in tillage, or its horizon, in which the processes of soil formation are equivalent in uncultivated soil, ranging in depth from 4 active. The solum in soil consists of the A, E, and B to 10 inches (10 to 25 centimeters). Frequently horizons. Generally, the characteristics of designated as the "plow layer," or the "Ap horizon." the material in these horizons are unlike those of the Tailwater. The water just downstream of a structure. substratum. The living roots and plant and Talus. Rock fragments of any size or shape, commonly animal activities are largely confined to the solum. coarse and angular, derived from and lying at the Stone line. A concentration of coarse fragments in a soil. base of a cliff or very steep, rock slope. The Generally, it is indicative of an old weathered surface. accumulated mass of such loose, broken rock formed In a cross section, the line may be one fragment or chiefly by falling, rolling, or sliding. more thick. It generally overlies material that Taxadjuncts. Soils that cannot be classified in a series weathered in place and is overlain by recent sediment recognized in the classification system. Such soils are of variable thickness. named for a series they strongly resemble and Stones. Rock fragments 10 to 24 inches (25 to 60 centimeters) in diameter if rounded or 6 to 15 are designated as taxadjuncts to that series quartz or feldspar. Includes peridotite and because they differ in ways too small to be of serpentinite. consequence in interpreting their use and Upland (geology). Land at a higher elevation, in general, behavior. than the alluvial plain or stream terrace; land above Terrace. An embankment, .or ridge, constructed across the lowlands along streams. sloping soils on the contour or at a slight angle to the Variant, soil. A soil having properties sufficiently different contour. The terrace intercepts surface runoff so that from those of other known soils to justify a new series water soaks into the soil or flows slowly to a name, but occurring in such a limited geographic area prepared outlet. A terrace in a field generally is built that creation of a new series is not justified. so that the field can be farmed. A terrace intended Variegation. Refers to patterns of contrasting colors mainly for drainage has a deep channel that is assumed to be inherited from the parent material maintained in permanent sod. rather than to be the result of poor drainage. Terrace (geologic). An old alluvial plain, ordinarily flat or Vegetative site. A distinctive kind of site that produces a undulating, bordering a river, a lake, or the sea. characteristic natural plant community that differs Texture, soil. The relative proportions of sand, silt, and from natural plant communities on other vegetative clay particles in a mass of soil. The basic textural sites in kind, amount, and proportion of forage plants. classes, in order of increasing proportion of fine Volcanic ash. Pyroclastic material less than 2 particles, are sand, loamy sand, sandy loam, loam, millimeters in diameter. silt loam, silt, sandy clay loam,, clay loam, silty clay Water bars. Smooth, shallow ditches or depressional areas loam, sandy clay, silty clay, and clay. The sand, that are excavated at an angle across a sloping road. loamy sand, and sandy loam classes may be further They are used to reduce the downward velocity of divided by specifying "coarse," "fine," or "very fine." water and divert it off and away from the road surface. Thin layer (in tables). Otherwise suitable soil material Water bars can easily be driven over if constructed too thin for the specified use. properly. Tilth, soil. The physical condition of the soil as related to Weathering. All physical and chemical changes produced tillage, seedbed preparation, seedling emergence, in rocks or other deposits at or near the earth's and root penetration. surface by atmospheric agents. These changes result Toe slope . The outermost inclined surface at the base of in disintegration and decomposition of the material. a hill; part of a foot slope. Well graded. Refers to soil material consisting of coarse Topsoil. The upper part of the soil, which is the most grained particles that are well distributed over a favorable material for plant growth. It is ordinarily wide range in size or diameter. Such soil normally rich in organic matter and is used to topdress can be easily increased in density and bearing roadbanks, lawns, and land affected by mining. properties by compaction. Contrasts with poorly Tuff. A compacted deposit that is 50 percent or more graded soil. volcanic ash and dust. Windthrow. The uprooting and tipping over of trees Ultramafic rock. Rock that has a relatively high content of through the action of the wind. iron, less than 45 percent silica, and virtually no