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Home , Aspect (geography), Boston Mountains, Cascades (ecoregion), Columbia Plateau, Imnaha River, Piedmont (ecoregion)

1 . C o a s t R a n g e When water levels are optimum in high quality The low of 1 are covered by highly productive, rain-drenched evergreen forests. Sitka spruce forests originally dominated the fog-shrouded coast, while a mosaic of western redcedar, western hemlock, and seral Douglas-fir blanketed inland areas. rivers in the Coast Range (1), chinook and coho Today, Douglas-fir plantations are prevalent on the intensively logged and managed landscape. Lithology influences land management strategies; slopes underlain by are more susceptible to failure following clear-cutting and road building than those salmon fight their way upstream to spawn. underlain by volcanic rocks. of The Coastal Lowlands ecoregion contains beaches, dunes, and marine terraces below 400 feet elevation. Wet forests, lakes, replaced the historic forests of the Willapa Hills (1f). When disturbed, the silt- and clay-textured are easily eroded, thereby 1a estuarine marshes, and tea-colored (tannic) streams are characteristic features of the landscape. Wetlands have been widely degrading stream quality. Large herds of Roosevelt winter in Ecoregion 1f. drained and converted to dairy pastures. Residential, commercial, and recreational developments are expanding in the coastal corridor. The mountainous Mid-Coastal Sedimentary ecoregion lies outside of the coastal fog zone and is typically underlain by Ecoregions denote areas of general similarity in ecosystems and in the type, quality, and quantity and Blue Mountains were originally published in Clarke and Bryce (1997). Ecoregion boundaries Gallant, A.L., Whittier, T.R., Larsen, D.P., Omernik, J.M., and Hughes, R.M., 1989, Regionalization as a The Coastal Uplands includes headlands and low mountains surrounding the Coastal Lowlands (1a). The of 1g massive beds of sandstone and siltstone in contrast to the volcanics of Ecoregion 1d. Ecoregion 1g is more rugged than the of environmental resources; they are designed to serve as a spatial framework for the research, in the remainder of Oregon depict revisions and subdivisions of earlier level III ecoregions that tool for managing environmental resources: Corvallis, Oregon, U.S. Environmental Protection Agency, 1b Ecoregion 1b is marine influenced with an extended winter rainy season and minimal seasonal temperature extremes. geologically similar Willapa Hills (1f). Its Douglas-fir forests are intensively managed for logging. Slopes are prone to failure when assessment, management, and monitoring of ecosystems and ecosystem components. By were originally compiled at a coarser scale (Omernik, 1987; USEPA, 2003). EPA/600/3-89/060, 152 p. Abundant fog during the summer dry season reduces vegetation moisture stress. Ecoregion 1b includes much of the historic disturbed, particularly south of the Siuslaw River. Stream sedimentation is higher than in the Volcanics ecoregion. recognizing the spatial differences in the capacities and potentials of ecosystems, ecoregions Griffith, G.E., Omernik, J.M., Wilton, T.F., and Pierson, S.M., 1994, Ecoregions and subregions of – a This poster is the product of a collaborative effort primarily between the USEPA Region X, the distribution of Sitka spruce. Today, its Douglas-fir forests are managed for logging. The Coastal Mountains is a geologically and botanically diverse ecoregion that is a transition zone stratify the environment by its probable response to disturbance (Bryce and others, 1999). framework for water quality assessment and management: Journal of the Iowa Academy of Science, v. USEPA National Health and Environmental Effects Research Laboratory (Corvallis, Oregon), the The lower, more coastal parts of the mountainous Volcanics ecoregion are affected by fog. Ecoregion 1d is underlain by 1h between the Coast Range and the Siskiyou Mountains. Ecoregion 1h has the climate of the Coast Range (1) and the varied Ecoregions are directly applicable to the immediate needs of state agencies, including the 101, no. 1, p. 5-13. Oregon Natural Heritage Program, the Department of Agriculture–Forest Service 1d lithology of the higher, more dissected Siskiyou Mountains (in Ecoregion 78). Distributions of northern and southern vegetation blend development of biological criteria and water quality standards and the establishment of Hughes, R.M., Whittier, T.R., Rohm, C.M., and Larsen, D.P., 1990, A regional framework for establishing fractured basaltic rocks. As a result, summer stream flows are more consistent than on the sedimentary rocks of surrounding (USFS), the United States Department of Agriculture–Natural Resources Conservation Service together here and species diversity is high. Douglas-fir, western hemlock, tanoak, Port Orford cedar, and western redcedar occur. management goals for nonpoint-source pollution (Omernik and Griffith, 1991; Hughes and recovery criteria: Environmental Management, v. 14, no. 5, p. 673-683. ecoregions, and streams still support runs of spring and summer steelhead. Its Douglas-fir plantations are intensively Oregon's coastline contains high, rugged (NRCS) (formerly the Conservation Service), and the United States Department of the headlands and intervening, lower marine terraces, others, 1990; Whittier and others, 1988). They are also relevant to integrated ecosystem McGrath, C.L., Woods A.J., Omernik, J.M., Bryce, S.A., Edmondson, M., Nesser, J.A., Shelden, J., logged. Sediment delivery rates to streams following disturbance are lower than in Ecoregion 1g. The low mountains of the Redwood Zone lie entirely within the coastal fog zone and are characteristically covered by coast Interior–Geological Survey (USGS)–Earth Resources Observation Systems (EROS) Data Center. Crawford, R.C., Comstock, J.A., and Plocher, M.D., 2002, Ecoregions of : Reston, Virginia, U.S. The Coast Range ecoregion (1) is composed of low elevation, maritime-influenced mountains. Its 1i beaches, and sand dunes of the Coastal Lowlands management, an ultimate goal of many federal and state resource management agencies. The Willapa Hills ecoregion is more rolling and has a lower drainage density than other upland areas in the Coast Range (1). redwood and Douglas-fir. Historically, unbroken redwood forests occurred and moderated local climate by trapping coastal (1a). Harbors are rare. Geological Survey, map scale 1:1,350,000. original Sitka spruce, western hemlock, and Douglas-fir forests have been largely transformed into The Oregon ecoregion project is part of an interagency effort to develop a common framework of Douglas-fir plantations through intensive timber management. 1f Logging is relatively easy and less expensive in this accessible . Industrial timberland has almost completely fog and producing shade. Remnants of unlogged redwood forest still survive east of Brookings. The approach used to compile this map is based on the premise that ecological regions can be Omernik, J.M., 1987, Ecoregions of the conterminous United States (map supplement): Annals of the identified through the analysis of the spatial patterns and the composition of biotic and abiotic ecological regions for the United States. Reaching that objective requires recognition of the differences in the conceptual approaches and mapping methodologies applied to develop the most Association of American Geographers, v. 77, no. 1, p. 118-125, scale 1:7,500,000. phenomena that affect or reflect differences in ecosystem quality and integrity (Wiken, 1986; Omernik, J.M., 1995, Ecoregions – a framework for environmental management, in Davis, W.S. and Simon, Omernik, 1987, 1995). These phenomena include , physiography, vegetation, climate, common ecoregion-type frameworks, including those developed by the USFS (Bailey and others, 1994), the USEPA (Omernik, 1987, 1995), and the NRCS (U.S. Department of Agriculture–Soil T.P., eds., Biological assessment and criteria-tools for water resource planning and decision making: 3 . W i l l a m e t t e V a l l e y soils, land use, wildlife distributions, and hydrology. The relative importance of each Boca Raton, Florida, Lewis Publishers, p. 49-62. characteristic varies from one ecological region to another regardless of the hierarchical level. A Conservation Service, 1981). As each of these frameworks is further refined, their differences are Ecoregion 3 contains terraces and floodplains of the system, scattered hills, , and adjacent foothills. Originally, it was covered by prairies, oak savanna, coniferous forests, extensive wetlands, and deciduous riparian forests. Elevation and relief are becoming less discernible. Regional collaborative projects, such as this one in Oregon, where Omernik, J.M., Chapman, S.S., Lillie, R.A., and Dumke, R.T., 2000, Ecoregions of Wisconsin: Transactions lower and the vegetation mosaic differs from the coniferous forests of the surrounding Coast Range (1), (4), and Klamath Mountains (78). Mean annual rainfall is 37 to 60 inches and summers are generally dry; overall, precipitation is lower than in the surrounding Roman numeral hierarchical scheme has been adopted for different levels of ecological regions. of the Wisconsin Academy of Sciences, Arts, and Letters, v. 88, p. 77-103. Level I is the coarsest level, dividing North America into 15 ecological regions. Level II divides agreement has been reached among multiple resource management agencies, are a step toward mountains. Today, the Willamette (3) contains the bulk of Oregon’s population, industry, commerce, and cropland. Productive soils and a temperate climate make it one of the most important agricultural areas in Oregon. attaining consensus and consistency in ecoregion frameworks for the entire nation. Omernik, J.M. and Griffith, G.E., 1991, Ecological regions vs. hydrologic units: frameworks for managing the continent into 52 regions (Commission for Environmental Cooperation Working Group, water quality: Journal of Soil and Water Conservation, v. 46, no. 5, p. 334-340. The nearly level to undulating Portland/Vancouver Basin is a depression at the base of the Portland Hills fault block. It The nearly level to undulating Prairie Terraces ecoregion includes all of the terraces of the Willamette River upstream of 1997). At level III, the continental United States contains 104 ecoregions and the conterminous 3a contains the confluence of the Columbia and Willamette Rivers and is composed of deltaic sands and gravels deposited by 3c the Portland/Vancouver Basin (3a). Ecoregion 3c is drained by low-gradient, meandering streams and rivers. Its broad United States has 84 ecoregions (United States Environmental Protection Agency [USEPA], Literature Cited: Pater, D.E., Bryce, S.A., Thorson, T.D., Kagan, J., Chappell, C., Omernik, J.M., Azevedo, S.H., and Woods, Bailey, R.G., Avers, P.E., King, T., and McNab, W.H., eds., 1994, Ecoregions and subregions of the United A.J., 1998, Ecoregions of Western and Oregon: Reston, Virginia, U.S. Geological Survey, floods. Historically, prairie, oak woodland, Douglas-fir, and Oregon ash grew on terraces and wetland margins. Today, fluvial terraces once supported oak savanna and prairies that were maintained by burning; wetter areas supported Oregon ash and 2003). Level IV is a further subdivision of level III ecoregions. Explanations of the methods used map scale 1:1,350,000. many wetlands, oxbow lakes, and ponds still occur, but, overall, the Portland/Vancouver Basin (3a) is dominated by urban and black cottonwood. Today, only relict native prairie remain. The poorly drained soils derived from glacio-lacustrine deposits are to define the USEPA’s ecoregions are given in Omernik (1995), Omernik and others (2000), States (map) (supplementary table of map unit descriptions compiled and edited by McNab, W.H. and Bailey, R.G.): Washington, D.C., USFS, scale 1:7,500,000. U.S. Department of Agriculture–Soil Conservation Service, 1981, Land resource regions and major land suburban development, pastures, and nurseries. The climate is usually marine-influenced but, periodically, easterly entering via extensively farmed for grass seed and small grains. Grasses tolerate poor drainage and poor rooting conditions better than other crops. Griffith and others (1994), and Gallant and others (1989). Bryce, S.A., Omernik, J.M., and Larsen, D.P., 1999, Ecoregions – a geographic framework to guide risk resource areas of the United States: Agriculture Handbook 296, 156 p. the Gorge bring continental temperature extremes to the Portland/Vancouver Basin (3a). In addition to agriculture, the Prairie Terraces also experience the bulk of urban expansion. Oregon is ecologically diverse. The west side of the state has a marine-influenced climate and characterization and ecosystem management: Environmental Practice, v. 1, no. 3, p. 141-155. U.S. Environmental Protection Agency, 2003, Level III ecoregions of the continental United States (revision The Willamette River and Tributaries Gallery Forest ecoregion includes low-gradient, meandering, river channels, broad The Valley Foothills ecoregion is a transitional zone between the agricultural and the more heavily receives plentiful precipitation three seasons of the year. In contrast, lies in the Bryce, S.A., Woods A.J., Morefield, J.D., Omernik, J.M., McKay, T.R., Brackley, G.K., Hall, R.K., Higgins, of Omernik, 1987): Corvallis, Oregon, USEPA – National Health and Environmental Effects Research 3b 3d Laboratory, Map M-1, various scales. floodplains, oxbow lakes, and meander scars. Riparian gallery forests containing ash, black cottonwood, alder, and bigleaf forested Cascade and Coast ranges. The forest canopy of Ecoregion 3d is dominated by Oregon white oak and Douglas-fir. Wildlife refuges in the Willamette Valley (3) A mosaic of Oregon white oak and Douglas-fir rain shadow of the Cascades and is much drier. The climatic gradient is evident in the state's D.K., McMorran, D.C., Vargas, K.E., Petersen, E.B., Zamudio, D.C., and Comstock, J.A., 2003, maple once grew on its fertile, alluvial soils, but most have been replaced by agriculture and rural residential, suburban, and urban The Valley Foothills (3d) receive less precipitation than adjacent mountainous ecoregions. Eastern foothills are wetter than those that preserve and restore wetland habitats and provide woodland, small farms, pastureland, and landscapes: forested mountains, glaciated peaks, shrub- and grass-covered plains, agricultural Ecoregions of Nevada: Reston, Virginia, U.S. Geological Survey, map scale 1:1,350,000. Wiken, E., 1986, Terrestrial ecozones of Canada: Ottawa, Environment Canada, Ecological Land development. Ecoregion 3b includes the major historic floodplains of the Willamette River system that rarely function today due to lie on the western side of the Willamette Valley in the lee of the Coast Range (1). Today, rural residential development, pastureland, winter habitat for waterfowl, wading birds, and vineyards covers the Valley Foothills (3d). The valleys, beaches, desert playas, and wetlands. There are 9 level III ecoregions and 65 level IV Classification Series no. 19, 26 p. several subspecies of Canada geese, including the woodland corridors bring Coast Range (1) Clarke, S.E., and Bryce, S.A., eds., 1997, Hierarchical subdivisions of the and Blue flood control dams upstream. Dams in the upper Willamette Basin reduce both flood frequency and flood volume, which are related to vineyards, tree farms, and orchards are common in Ecoregion 3d. The foothills also serve as a wildlife corridor between the ecoregions in Oregon and many continue into ecologically similar parts of adjacent states (Bryce Mountains Ecoregions, Oregon and Washington: Portland, Oregon, USFS, Research Whittier, T.R., Hughes, R.M., and Larsen, D.P., 1988, Correspondence between ecoregions and spatial endangered Dusky Canada Goose. wildlife, such as elk, , , and , the decline of the endemic, endangered Oregon chub. Willamette Valley and the surrounding mountains. into the Willamette Valley. and others, 2003; McGrath and others, 2002; Pater and others, 1998). Station, General Technical Report PNW-GTR-395. patterns in stream ecosystems in Oregon: Canadian Journal of Fisheries and Aquatic Sciences, v. 45, p. The agricultural patchwork on the terraces and floodplains of the Willamette Valley (3). 1264-1278. This level III and IV ecoregion map was compiled at a scale of 1:250,000. The western part was Commission for Environmental Cooperation Working Group, 1997, Ecological regions of North America – toward a common perspective: Montreal, Commission for Environmental Cooperation, 71 p. originally published as part of Pater and others (1998). The level IV lines in the Columbia Plateau 4 . C a s c a d e s Clear cutting, log yarding, and road building have degraded downstream water quality in the The mountains of Ecoregion 4 are widely underlain by Cenozoic volcanic rocks and have been affected by alpine glaciation. Maximum elevations of up to 11,239 feet occur on active and dormant volcanic peaks in the eastern part of Ecoregion 4. The western Cascades are medium to high gradient streams of Ecoregion 4. older, lower, and dissected by numerous, steep-sided stream valleys. Ecoregion 4 has a moist, temperate climate that supports an extensive and highly productive coniferous forest that is intensively managed for logging. Subalpine occur at high elevations. However, remnant old growth forests still occur 124° 123° 122° 121° 120° 119° 118° 117° that support old growth dependent wildlife 1 The Western Cascades Lowlands and Valleys ecoregion includes the lower slopes of the Cascades (4). Its mild, wet and permanent snowfields still occur on the highest peaks. The vegetation is adapted to high elevations, cold winter temperatures, species such as the red vole and the northern 15 4a spotted owl. Astoria 2 climate promotes lush western hemlock–Douglas-fir forests. Soils are warmer than in higher elevation ecoregions. The steep short growing season, and deep winter pack. Herbaceous subalpine vegetation and scattered patches of Pasco 10 1a Richland valleys contain high gradient rivers and streams that support cold water salmonids, including the threatened chinook salmon, hemlock, subalpine fir, and whitebark pine occur near timberline. Longview 10 steelhead, and . Reservoirs store winter snow melt for and municipal water supply in the Willamette Valley (3). The heavy snow Kennewick 4e The High Southern Cascades Montane Forest ecoregion is an undulating, glaciated, volcanic plateau containing isolated pack in the high 46° 1d Walla Walla 11 The Western Cascades Montane Highlands are composed of steeply sloping, dissected mountains between about 3,000 buttes, cones, and peaks. The terrain is less dissected than the Southern Cascades (4f). At 4,000 to 8,200 feet, maximum Cascades (4) 1f 10 11 er 46° 4b provides water Riv and 6,500 feet elevation. The western Cascades are older and more eroded than the lava plateau and prominent snow-covered elevations are intermediate to those in the Southern Cascades (4f) and the Cascades Subalpine/Alpine ecoregion (4d). Cryic soils m to lowland areas le 1f cones of the high Cascades (Ecoregions 4c and 4d); they are composed of dark in contrast to the gray andesite of the high support mixed coniferous forests dominated by mountain hemlock, lodgepole pine, and Pacific silver fir; they are colder than the 1b a as well as winter eh Milton- 10e N 4 11c Cascades. Ecoregion 4b has lower temperatures and receives more winter snow than the Western Cascades Lowlands and Valleys mesic and frigid soils of the Southern Cascades (4f). Grand fir, white fir, and Shasta red fir also occur and become more common 10g Freewater recreation. 1d Saint 9 Umatilla (4a). Soils have frigid or cryic temperature regimes, in contrast to the mesic temperature regime of soils in Ecoregion 4a. Abundant toward the south and east. The High Southern Cascades Montane Forest (4e) has a longer summer and more intermittent Helens

Hermiston 11l 11f precipitation supports forests dominated by Douglas-fir, western hemlock, noble fir, and Pacific silver fir. streams than the Cascade Crest Montane Forest (4c). Pacific

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1a 1f t The Cascade Crest Montane Forest ecoregion consists of an undulating plateau punctuated by volcanic mountains and lava The Southern Cascades ecoregion is lower in elevation and less rugged than the more highly dissected Western Cascades

r il 10i W v 4c blooms in June e 10e i a N l 4f O a iv a a 11f flows. Volcanism in the Pliocene epoch overtopped the existing Miocene volcanics of Ecoregion 4b. Later Pleistocene Montane Highlands (4b) to the north. Mt. McLoughlin, at 9500 feet, is the highest peak in Ecoregion 4f. The climate is drier

T bi R Pendleton in the G l R IN Hood Colum River l ow

H a e Vancouver S glaciation left numerous naturally-fishless lakes. Today, Ecoregion 4c contains forests dominated by mountain hemlock and Pacific than in the Western Cascades Lowlands and Valleys (4a) and the Western Cascades Montane Highlands (4b), and the vegetation understory of A River 11l R Imnaha W i e 3a ve silver fir. It has a shorter summer drought and fewer intermittent streams than the High Southern Cascades Montane Forest (4e). reflects it. Western hemlock and western red cedar, which are indicator species of Ecoregions 4a and 4b, decline southward in the the conifer c Portland r k forests of Tillamook Hillsboro 3c The 11k a The Cascades Subalpine/Alpine ecoregion contains the prominent volcanic peaks of the high Cascades. Pleistocene Southern Cascades (4f), and are replaced by species such as incense cedar, white fir, and Shasta red fir that tolerate 1d Gresham 4b Dalles n Snow and -clad volcanic peaks, such as Mt. Hood pictured here (4d), rise above the heavily Ecoregion 4b. 1a Beaverton S 10c Enterprise r 4d prolonged summer drought. Overall, river and stream discharge is also significantly lower than in systems to the north. O 11g e forested Cascade crest plateau (4c). Photo: Ron Nichols, NRCS glaciation reshaped the mountains above 6500 feet, leaving , glacial lakes, and U-shaped glacial . v Moro i Hells R 1b

Canyon Heppner 11l hon Rive 1d 4d R de r 10c NRA

3c Oregon 9c e 1b d 3d n 9b 10k a 11f City 10n La Grande C r 11l Timber management in Ecoregion 9 benefits elk l M a 9 . E a s t e r n C a s c a d e s S l o p e s a n d F o o t h i l l s ac G ka Condon 11l in h that frequent young forest stands. c 3d m a a Ecoregion 9 is in the rainshadow of the . It experiences greater temperature extremes and receives less precipitation than ecoregions to the west. Open forests of ponderosa pine and some lodgepole pine distinguish this region from the higher ecoregions to the McMinnville a 11k m n 1g 3d s 4b 10c 11c R 11m i 10k i m v r I e west where hemlock and fir forests are common, and the lower, drier ecoregions to the east where shrubs and grasslands are predominant. The vegetation is adapted to the prevailing dry, continental climate and frequent fire. Historically, creeping ground fires consumed 11o R f 11l 3c i 45° 1b v 10k accumulated fuel and devastating crown fires were less common in dry forests. e 11l i 11l Lincoln r 4c 11o 45° City The Grand Fir Mixed Forest ecoregion is mostly outside the limit of maritime climatic influence. It is characterized by 9f have water tables at or near the surface for significant periods of the year in contrast to Ecoregion 9e. Marshes and forested c 11b 11e Dallas 11d 9b high, glaciated plateaus and mountains, frigid soils, and a snow-dominated, continental climate. Grand fir, Douglas-fir, wetlands provide important habitat for migratory waterfowl. Salem P Fossil o a 11b r w ponderosa pine, and larch occur. Ecoregion 9b is higher and moister than Ecoregion 9c, but the boundary between them is not sharp. e d The Klamath/Goose Lake Basins ecoregion covers river floodplains, terraces, and lake basins. A variety of wildrye, Deep, well- to Si v 11a er le i R t R 3d 11m iv 9g excessively- P z 4b 11k er Halfway The Oak/Conifer Foothills ecoregion is more diverse than other parts of Ecoregion 9. Marine weather enters Ecoregion 9c bluegrass, and wheatgrass species once covered the basins, but most of the wet meadows and wetlands have been drained for Santiam River 11d drained, 1b rth ay 9c No R Detroit D 11l via the , moderating its otherwise continental climate. As a result, soil, climate, and vegetation share agriculture. Several marshland wildlife refuges are key to preserving regional biodiversity, particularly at-risk bird and fish species. iver hn pumice- derived Lake r 9d Jo 11m Baker City characteristics of both eastern and . Grasslands, oak woodlands, and forests dominated by ponderosa pine, and soils are a S e Newport o 11a 11d The Fremont Pine/Fir Forest ecoregion contains mid-elevation mountains and high plateaus that rarely exceed timberline. u 11o Albany t v Douglas-fir occur. Ecoregion 9c is lower and drier than the Grand Fir Mixed Forest ecoregion (9b). 9h feature of the h 4d i 11 Closed canopy forests contrast with the savanna of the Klamath Juniper Woodland (9j). Ponderosa pine is widespread, but r 11b S 4b Pumice Plateau e 11d a3c R n v Madras nt The undulating volcanic plateaus and canyons of the Ponderosa Pine/Bitterbrush Woodland have well-drained, frigid soils white fir, sugar pine, and incense cedar also grow above 6500 feet and on north slopes. Residual soils are common in contrast to i ur R 11d (9e). Corvallis t Lake 11o B iv Lebenon i R 11l 11l 9d a e r that are often derived from ash. Ponderosa pine is common; lodgepole pine is largely absent unlike in the Pumice Plateau Ecoregion 9e, where residual soils have been deeply buried by pumice and ash. Ecoregion 9h has a high density of lakes and reservoirs. m s Billy e u i 1d R 4b Chinook k 3c l 11l (9e). Understory vegetation varies with elevation; at lower elevations, antelope bitterbrush is important winter browse for deer.

W i 3c v o a The Southern Cascades Slope ecoregion is a transitional zone between the Cascades (4) and the drier Eastern Cascade Als r e t 11d e e i e n 9i a r 9b v l i D 11l

l John Day The Pumice Plateau ecoregion is a high volcanic plateau. Ecoregion 9e is characteristically covered by thick deposits of Slopes and Foothills (9). Ecoregion 9i is higher and moister than ecoregion 9h, and it has a greater mix of forest types. 11l S R Green M a e m 9e Peter Lake s 1d c pumice and volcanic ash. Soils are very deep, highly permeable, and droughty. Spring-fed creeks and marshes occur. Ponderosa pine woodland becomes mixed with white fir, incense cedar, Shasta red fir, and Douglas-fir at higher elevations. e h 11l t 4c Crooked 11o t 3b u 11l e Prineville Ponderosa pine forests are common on slopes; colder depressions and flats are dominated by lodgepole pine and higher elevations t The Klamath Juniper Woodland ecoregion is composed of undulating hills, benches, and escarpments covered with a Historically, frequent fires in the dry ponderosa

e Sisters

s 11b

9j

R have white fir. Freezing temperatures are possible any time of year. pine woodlands burned undergrowth and

1d 4d 11m

mosaic of rangeland and woodland. Western juniper grows on shallow, rocky soils with an understory of low sagebrush, big i R

1g v R Redmond Weiser Gently rolling topography covered by open forests characterizes the Eastern Cascades Slopes and seedling trees creating open groves of pines. i

e i 11i

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v 12j r The Pumice Plateau Basins ecoregion includes Sycan Marsh, Klamath Marsh, and La Pine Basin. All three areas function sagebrush, bitterbrush, and bunchgrasses. Other shrubland/grasslands include shrub species uncommon in eastern Oregon, such as

3c 4a e e Foothills (9). Though ponderosa pine dominates most of the ecoregion, lodgepole pine grows better Photo: Sharon Clarke, OSU enzi r 11n r 11o cK e Riv r in areas of cold air drainage and extremely permeable soils as shown here in Ecoregion 9e. 9f as catch-basins for cold air during the winter and have lower minimum temperatures than Ecoregion 9e. Soils in Ecoregion woolly wyethia, Klamath plum, and birchleaf mountain mahogany. The diverse shrublands provide important wildlife habitat. M e Prineville 11o Payette 44 1a Sius 12a ° 1b l Reservoir Florence a Eugene Bend w Fern 44°

11b Ontario Reservior

Ri ver r 12j 1 0 . C o l u m b i a P l a t e a u ve 3d s Ri 12 Ecoregion 10 is an arid, sagebrush steppe and grassland that is flanked by moister, predominantly forested, mountainous ecoregions. The Columbia Plateau (10) is underlain by basalt up to two miles thick and partially covered by thick loess deposits. Where precipitation 1b 11h ie 11o v Crane Prairie l Waldo i ver amounts are sufficient, its deep loess soils have been extensively cultivated for wheat. The Columbia River bisects Ecoregion 10; its water is subject to resource allocation debates involving fisheries, navigation, power production, recreation, and irrigation. Reedsport Reservoir S i Oakridge Lake R

80d 80d The nearly level to rolling, treeless Umatilla Plateau ecoregion is underlain by basalt and veneered with loess deposits. The Deep Loess Foothills have highly-productive, loess-rich soils. Moisture levels are high enough to support Idaho fescue Ump r qua Hills 4c Caldwell 1b u 10c 10i Creek e Areas with thick loess deposits are farmed for dry land winter wheat, or irrigated alfalfa and barley. In contrast, rangeland and bluebunch wheatgrass grasslands. Today, Ecoregion 10i is dominated by non-irrigated winter wheat, barley, alfalfa, and h l Res. a dominates more rugged areas where loess deposits are thinner or nonexistent, such as in neighboring Ecoregions 10k and 10n. Mean green pea farming. Land use contrasts with the rangeland of the Umatilla Dissected Uplands (10n). Perennial streams occur that are R Wickiup LaPine M i v Reservoir annual precipitation is 9 to 15 inches and increases with increasing elevation. In uncultivated areas, moisture levels are generally high fed by the precipitation that falls on the adjacent Blue Mountains (11). e 4b Burns 1a r 4d 80j Lake enough to support grasslands of bluebunch wheatgrass and Idaho fescue without associated sagebrush, which is more common in 10e. 1b 80f Owyhee Deeply cut into basalt, the Deschutes/John Day Canyons fragment a lightly populated portion of the Umatilla Plateau 9f 80e 10k Coos Bay The Pleistocene Lake Basins once contained vast temporary lakes that were created by flood waters from glacial lakes (10c). depths up to 2,000 feet create drier conditions than on the plateau above. In the canyons, bunchgrasses,

I 80d D 10e Missoula and Columbia. In Oregon, the flood waters accumulated from the eastern entrance of the Columbia River Gorge Wyoming big sagebrush, and cheatgrass grow on rocky, colluvial soil. Riparian vegetation in narrow reaches is often limited to a band 1b 4d A

78c R Malheur 80f H No h Um iv upstream to the to form ancient Lake Condon. Today, Ecoregion 10e is the driest and warmest part of the Columbia of white alder at the water line; broader floodplains and gravel bars are dominated by introduced species, such as reed canarygrass, rt a e 80j O p qu r Lake Irrigation projects supply Columbia River water In protected, ungrazed areas one may still 80d 1b Roseburg Plateau (10) with mean annual precipitation varying from 7 to 10 inches. Native vegetation consists of bunchgrass and sagebrush. sweetclover, and teasel. The rivers support chinook salmon and steelhead runs. to the Pleistocene Lake Beds (10e), the driest encounter the bunchgrasses that grew in 80d 9e Christmas Major irrigation projects provide Columbia River water to Ecoregion 10e, allowing the conversion of large areas into agriculture. portion of the Columbia Plateau (10). They have association with sagebrush and juniper across Coquille D 4d Valley In the Umatilla Dissected Uplands, the dry grasslands of the Columbia Plateau (10) meet the forested Blue Mountains (11). o 10n allowed the conversion of large areas into vast areas of Ecoregions 10, 11, and 80. n The Yakima Folds ecoregion consists of unforested anticlinal composed of layer upon layer of basalt many thousands The steep, dissected hills and terraced uplands are covered with Idaho fescue, bluebunch wheatgrass, and Sandberg 80g n cropland producing potatoes, wheat, alfalfa, and Bluebunch wheatgrass, pictured here, and Idaho 1a 4b 80e e r 10g

1b of feet thick. Loess blankets the south-facing slopes and supports dryland wheat farming. Steep, rocky north-facing slopes bluegrass. Near the Blue Mountains, some north-facing slopes have Douglas-fir and ponderosa pine. Ecoregion 10n is mostly used as r silage corn. Here, a center pivot system irrigates fescue do not withstand intense grazing pressure 43° e 80m iv R sandy Adkins soil. Photo: NRCS and have been replaced by alien cheatgrass. a 43° are commonly used for livestock grazing. Ecoregion 10g receives an average of 10 to 12 inches of rain per year. Sagebrush and rangeland because it lacks the thick, arable loess deposits that cover the agricultural Umatilla Plateau (10c). Scablands, composed of u Loess soils in the nearly level to rolling Umatilla Plateau (10c) that once supported bunchgrass q p 4e a Jordan Valley

m Crater n prairies are now widely cultivated for winter wheat. bunchgrass associations dominate plant assemblages outside of heavily farmed or grazed areas. arrays of earth mounds surrounded by rock polygons, are relics of Pleistocene glacial periods. S 80g d

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4d r ve 78e i R 80f Burns O B wy 9f Summer he l Junction e R 78d 4d i i t v 1 1 . B l u e M o u n t a i n s Lake z er n e 80 o Frenchglen n Rogue s Ecoregion 11 is a complex of mountain ranges that are lower and more open than the neighboring Cascades (4) and Northern Rockies (15). Like the Cascades (4), but unlike the Northern Rockies (15), the Blue Mountains (11) are mostly volcanic in origin. However, the core R m i R a Warner 80k v Lake i i of the Blue Mountains and the highest ranges, the Wallowa and Elkhorn Mountains, are composed of granitic intrusives, deep sea sediments, and metamorphosed rocks. Much of Ecoregion 11 is grazed by cattle, unlike Ecoregions 4 and 15. e l 80e v l Lakes e r a Abert i Spr gu r e 80a W R The semiarid John Day/Clarno Uplands form a ring of dry foothills surrounding the western perimeter of the Blue The mountainous Continental Zone Highlands experience seasonal temperature extremes and low annual precipitation. 9g iv 80d 78b e 11a 11h 1b Grants 4d Chiloquin r Mountains. Highly dissected hills, palisades, and colorful ash beds flank the valleys of the John Day and Crooked Rivers. The predominant forest cover is ponderosa pine with a shrub or bunchgrass understory. As in Ecoregion 11b, frequent fires 78b Pass 80m 80j I 80j 80e Ecoregion 11a has a continental climate moderated somewhat by marine influence. Juniper woodland has expanded markedly into the once influenced the open character of the forest. Ecoregion 11h lacks a zone of true firs found in other highland areas in the Blue llin 78a 80f Gold oi 9g 80j s 78a 9g sagebrush-grassland during the 20th Century due to a combination of climatic factors, fire suppression, and grazing pressure. Mountains. Many of its perennial streams flow south to end in the alkaline basins of the Wetlands (80e). Beach Basque 80l 78d R 78b Medford 4d 80l i Upper The low mountains of the John Day/Clarno Highlands are uniformly covered by ponderosa pine forest with a grass and The Continental Zone Foothills lie in the rainshadow of the Cascade Range and Blue Mountains. Plants experience wide 1a ve 9h 78f r Klamath 11b 11i 78b Lake shrub understory. The continental climate is tempered by a marine influence; it is not as dry, nor are temperature extremes as temperature variations, high evapotranspiration rates, and high early-season moisture stress in the continental climate of Zumwalt Prairie, in 11g, is the largest remaining 9g 9h Ashland 80d great, as in the Continental Zone Highlands (11h). Historically, frequent low intensity fires reduced fuel loading in forests of widely Ecoregion 11i. The distribution of desert shrubs varies with soil depth, texture, and elevation. Mountain mahogany and bitterbrush expanse of bunchgrass prairie in Oregon. It will 78d Klamath Falls 9g Lakeview Fields be managed to protect a concentration of v spaced old-growth ponderosa pine. Today, after years of fire suppression and high grade logging, land managers attempt to emulate provide winter cover and forage for mule deer. Rodents, songbirds, and upland game birds also use the fruits of bitterbrush. Brookings 78a Ri er mammals, raptors, and threatened fish species. Oregon Caves NM th 9g 9g historical fire regimes to reverse the trend toward dense thickets of young growth that carry hot, stand-replacing fires. 1h 9i a The Blue Mountain Basins ecoregion includes the Wallowa, Grande Ronde, and Baker valleys. All three valleys are fault- Photo: Michael Durham for the Nature Conservancy 42° m 9j 80j 1i a 11k 78d 78g l 9j 80j 42° The Maritime-Influenced Zone is the portion of the Blue Mountains ecoregion that directly intercepts marine weather bounded grabens or depressions filled with sediments. The Wallowa and Grande Ronde valleys have a marine-moderated K 80l 11c 1 Goose 80d systems moving east through the Columbia River Gorge. In addition, loess and ash soils over basalt retain sufficient moisture climate and moisture retaining loess soils. The Baker Valley, located in the rainshadow of the Elkhorn Mountains, is drier and has 78 Lake NEVADA to support forest cover at lower elevations than elsewhere in the Blue Mountains. A dense and diverse shrub layer grows beneath the areas of alkaline soil. All three valleys receive stream flow from the surrounding mountains. Most of the floodplain wetlands have 9 80 North of Halfway, Oregon, the bunchgrass- and sagebrush-covered Continental Zone Foothills In Ecoregion 11a, riparian areas relatively open canopy of ponderosa pine and Douglas-fir which may delay tree regeneration following logging. been drained for agriculture, but a remnant exists in the Grande Ronde Basin at Ladd Marsh National Wildlife Refuge. 124° 123° 122° 121° 120° 119° 118° INTERIOR—G EOLOG ICAL S U RVEY, RES TON, VIRG INIA—2003 (11i) rise to meet the snow-covered (11e, 11m). that have lost the native shrub 117° The Melange ecoregion has a complex geology, composed of ocean sediments, granitic intrusions, and metamorphosed The disjunct Mesic Forest Zone includes the highest forested areas in the western Wallowas and the Blue Mountains. cover of willow, alder, or mock 11d 11l orange are subject to the invasion sediments. Soils are droughty and high in magnesium, creating a poor medium for plant growth; reforestation problems limit Ecoregion 11l is marine-influenced with higher precipitation than other forested Blue Mountains ecoregions (such as 11b, of alien plants such as cheatgrass, logging. Placer mining for gold altered the structure of many stream channels and left extensive tailings piles in riparian areas. 11d, and 11f). The ashy soil holds moisture during the dry season and supports a productive spruce-fir forest. The boundaries of leafy spurge, teasel, and mullein. Ecoregion 11l correspond to the distribution of true fir forest before the modern era of fire suppression and high grade logging. 1 Coast Range 9 Eastern Cascades Slopes and Foothills 11 Blue Mountains 78 Klamath Mountains 11e The Wallowas/Seven Devils Mountains ecoregion occupies the mid-elevation zone between the Subalpine-Alpine Zone 1a Coastal Lowlands 9b Grand Fir Mixed Forest 11a John Day/Clarno Uplands 78a Rogue/Illinois Valleys (11m) and the Continental Zone Foothills (11i). It is not as complex geologically as the Melange ecoregion (11d), although it The Subalpine–Alpine Zone begins where the forest cover becomes broken by alpine meadows, and continues through is also composed of ocean sediments. The character of its xeric forest of ponderosa pine and Douglas-fir varies between moister 11m alpine meadowland to include the exposed rock and snowfields of the highest mountain peaks. Subalpine fir, Engelmann Remnant aspen groves and spruce-fir forest 1b Coastal Uplands 9c Oak/Conifer Foothills 11b John Day/Clarno Highlands 78b Oak Savanna Foothills maritime-influenced and drier continental areas, particularly in the diversity and extent of the shrub understory. Streams following spruce, and whitebark pine tolerate the cold soils, deep snowpack, and extremely short growing season near timberline. Historically, surround a Cold Basin (11o) wet meadow. 1d Volcanics 9d Ponderosa Pine/Bitterbrush Woodland 11c Maritime-Influenced Zone 78c Umpqua Interior Foothills fault lines have eroded deep canyons, and mountain water is diverted or impounded for irrigation and drinking water. green fescue and sedges covered high alpine meadows and ridges particularly in the Wallowas; but, following intense sheep grazing in the early 20th Century, many alpine plant associations reverted to seral or exotic species on rocky subsoil. 1f Willapa Hills 9e Pumice Plateau 11d Melange 78d Serpentine Siskiyous 11f In the Canyons and Dissected Highlands ecoregion the uplifted Columbia Plateau basalt has been eroded to a series of 1g Mid-Coastal Sedimentary 9f Pumice Plateau Basins 11e Wallowas/Seven Devils Mountains 78e Inland Siskiyous knife-edge ridges flanked by deep canyons. Ecoregion 11f occupies the elevational zone above the unforested Canyons and 11n The Deschutes River Valley is a broad intermountain sagebrush–grassland. The climate of Ecoregion 11n has a marine 11f Canyons and Dissected Highlands Dissected Uplands (11g); it is drier than the marine-influenced Mesic Forest Zone (11l) that exists at similar elevations to the west. influence and is not as arid as in the botanically similar High Lava Plains (80g) to the southeast. Because of the proximity of 1h Southern Oregon Coastal Mountains 9g Klamath/Goose Lake Basins 78f Coastal Siskiyous Moisture retaining loess and ash soils support Douglas-fir, larch, and grand fir on relatively level benches and Douglas-fir in unstable the high Cascades (4) to the west, stream density and water availability are high. As a result, human population density is much higher 1i Redwood Zone 9h Fremont Pine/Fir Forest 11g Canyons and Dissected Uplands 78g Klamath River Ridges colluvial soils on steep canyon slopes. The steep terrain limits human activities. than in Ecoregion 80g. Canals carry river water to irrigated farms on floodplains and terraces. 9i Southern Cascades Slope 11h Continental Zone Highlands 3 Willamette Valley 11g In Oregon, the Canyons and Dissected Uplands include the Snake, Grande Ronde, and canyons that have cut 11o The Cold Basins ecoregion contains high, wet meadows. The high meadows are often alluvial and have a high water table Exposed rock, glacial rock basins, tarns, and 9j Klamath Juniper Woodland 11i Continental Zone Foothills 2,000 to 5,000 feet through the Columbia Plateau basalt and underlying metamorphic rocks. Stony colluvial soils retain little and silt or clay soils. Streams, if not channelized, are meandering and have a dynamic interaction with their flood plains. meadowland are found in the Subalpine–Alpine 3a Portland/Vancouver Basin 80 Northern Basin and Range 11k Blue Mountain Basins moisture and support bunch grasses and arid land shrubs. Grazing and recreation occur in National Recreation Area. These unconstrained streams provide pool habitats that are important to salmonids. The short growing season and saturated soil make Zone (11m) of the high Wallowa Mountains. 3b Willamette River and Tributaries Gallery Forest 80a Dissected High Lava Plateau Ash beds thousands of feet deep fill topographic basins in the John Day/Clarno Uplands (11a). The canyons provide a refuge for elk, bighorn sheep, mountain goats, and a concentration of wintering bald eagles. Of the major these basins unsuitable for most crops, except hay, but they are heavily grazed by cattle and elk. Bighorn sheep frequent the high elevation 11l Mesic Forest Zone Red, green, and gray ash beds hold the fossilized remains of Miocene mammals that have been Wallowa Mountains (11m) and the steep slopes 3c Prairie Terraces 80d Pluvial Lake Basins preserved in the John Day Fossil Beds National Monument. historic salmon stocks, the coho and sockeye are extinct, the chinook are threatened, and summer steelhead are in decline. of Hells Canyon (11g and 11f). 11m Subalpine–Alpine Zone 3d Valley Foothills 10 Columbia Plateau 80e High Desert Wetlands 11n Deschutes River Valley 10c Umatilla Plateau 80f Owyhee Uplands and Canyons 4 Cascades 11o Cold Basins 1 2 . S n a k e R i v e r P l a i n 10e Pleistocene Lake Basins 80g High Lava Plains 4a Western Cascades Lowlands and Valleys The plains and low hills of Ecoregion 12 are part of the xeric intermontane west. It is considerably lower and less rugged than surrounding ecoregions. Irrigation water is plentiful in many areas. Many of the alluvial valleys bordering the Snake River are in agriculture and 10g Yakima Folds 80j Semiarid Uplands 4b Western Cascades Montane Highlands principally grow sugar beets, potatoes, alfalfa, small grains, and vegetables. The remainder of the Snake River Plain (12) in Oregon is covered by sagebrush–grassland and is used for cattle grazing. 10i Deep Loess Foothills 12 Snake River Plain 80k Partly Forested Mountains 4c Cascade Crest Montane Forest The ecoregion flanks the Snake and Malheur rivers and is underlain by Quaternary alluvium, loess, The Unwooded Alkaline Foothills ecoregion is shrub- and grass-covered. Ecoregion 12j contains rolling foothills, hills, 10k Deschutes/John Day Canyons 12a Treasure Valley 80l Salt Shrub Valleys 12a 12j 4d Cascade Subalpine/Alpine lacustrine, and alluvial fan deposits. Soils have an aridic moisture regime and they originally supported sagebrush/grass benches, alluvial fans, and scattered badlands that are characteristically underlain by alkaline lacustrine deposits. The terrain 10n Umatilla Dissected Uplands 12j Unwooded Alkaline Foothills 80m Barren Playas associations before the valley was converted to agriculture. Canals and diversions in this portion of the Snake River Plain (12) supply is higher and more rugged than the neighboring Treasure Valley (12a). Perennial streams are rare. Ecoregion 12j is valuable as 4e High Southern Cascades Montane Forest water to pastureland and cropland as well as municipalities. Water quality in many stream reaches has been significantly affected by rangeland and wildlife habitat. Land use is generally distinct from the irrigated agriculture of the neighboring Treasure Valley (12a). 4f Southern Cascades channel alteration, dams, irrigation diversions, irrigation return flow, and agricultural pollution. Crops include wheat, sugar beets, However, scattered areas near rivers with enough water to leach salts from the soil, support alfalfa or sugar beet farming. Vegetation is alfalfa, potatoes, and onions. Population density is greater than in neighboring, rangeland-dominated ecoregions. Vegetation outside of dominated by Wyoming big sagebrush and associated grassses. Salt tolerant shrubs, including black greasewood, fourwing saltbush, agricultural areas is dominated by Wyoming big sagebrush, basin big sagebrush, bluebunch wheatgrass, and cheatgrass. In saline inland saltgrass, and shadscale, occur on alkaline outcrops. Surface-irrigated cropland and pastureland is Outcrops of alkaline lacustrine deposits occur on areas, shadscale, greasewood, and saltgrass occur. widespread in the Treasure Valley (12a). the hillslopes of Ecoregion 12j. Rangeland is SCALE 1:1 500 000 The Snake River is incised into the volcanic rocks of the Snake River Plain (12). River flow is extensive, but scattered areas near rivers, with interrupted by dams and diversions. An extensive network of canals provide water to irrigated sufficient water to leach salts from the soil, 15 10 5 0 30 60 mi pastureland, cropland, and municipalities. support alfalfa farming. Level III ecoregion County boundary Level IV ecoregion State boundary 30 20 10 0 60 120 km 7 8 . K l a m a t h M o u n t a i n s Summer drought affects the foothills and narrow Albers Equal Area Projection Ecoregion 78 encompasses the highly dissected ridges, foothills, and valleys of the Klamath and Siskiyou mountains. It was unglaciated during the Pleistocene epoch, when it served as a refuge for northern plant species. Its mix of granitic, sedimentary, metamorphic, and extrusive valleys of Ecoregion 78c. Standard parallels 43 N and 45 N rocks contrasts with the predominantly volcanic rocks of the Cascades (4). The mild, subhumid climate of the Klamath Mountains (78) is characterized by a lengthy summer drought. It supports a mosaic of both northern Californian and Pacific Northwestern conifers and hardwoods. The Rogue/Illinois Valleys ecoregion supports Oregon white oak and California black oak woodland, ponderosa pine, and The Serpentine Siskiyous ecoregion is lithologically distinct from the rest of Ecoregion 78. Many plants have difficulty 78a grassland. As in other highly developed valleys, little original vegetation remains. Remnants of oak savanna, prairie 78d growing in its serpentine soils due to a shortage of calcium and high levels of magnesium, nickel, and chromium. As a result, vegetation, and seasonal ponds persist on the mesa tops of the Table Rocks north of Medford. Elsewhere, land uses include orchards, vegetation is often sparse and composed of specialist species. Jeffrey pine and endemic oak and ceanothus species have evolved to cropland, and pastureland. Climate, vegetation, and resulting land use are more similar to northern California’s inland valleys than to grow in the potentially toxic and nutrient-poor serpentine soils. Historic mines and associated water quality problems occur. the Willamette Valley (3). Rare understory Level III Ecoregions of the Conterminous United States The forested Inland Siskiyous ecoregion is higher and more mountainous than neighboring foothill and valley ecoregions species and The Oak Savanna Foothills border the Rogue and Illinois river valleys (Ecoregion 78a), sharing their Mediterranean-type 78e (78a, 78b, and 78c). Ecoregion 78e has a higher fire frequency, less annual precipitation, and longer summer than sparse PRINCIPAL AUTHORS: Thor D. Thorson (NRCS), Sandra A. Bryce (Dynamac vegetation grow 1 Coast Range 29 Central /Texas Plains 57 Huron/Erie Lake Plains 78b climate. The driest area east of Medford is dominated by oak woodlands, grassland–savanna, ponderosa pine, and Douglas- the Coastal Siskiyous (78f). Forest cover in Ecoregion 78e is a diverse and multi-layered mix of conifers, broadleaf evergreens, and 77 Corporation), Duane A. Lammers (USFS), Alan J. Woods (Dynamac Corporation), on soils derived 1 2 2 Puget Lowland 30 58 Northeastern Highlands James M. Omernik (USEPA, retired), Jimmy Kagan (Oregon Natural Heritage fir. The wetter foothills flanking the Illinois Valley support Douglas-fir, madrone, and incense cedar. Ecoregion 78b is lower and less deciduous trees and shrubs in contrast to the predominantly coniferous forests that occur in the Coast Range (1) or Cascades (4). from serpentine 15 41 42 3 Willamette Valley 31 Southern Texas Plains 59 Northeastern Coastal Zone 10 dissected, with more oak woodland and less closed-canopied forest than the Inland Siskiyous (78e). in Ecoregion 49 4 Cascades 32 Texas Blackland Prairies 60 Northern Appalachian Plateau Program), David E. Pater (Water Quality Program, Washington Department of The Coastal Siskiyous ecoregion has a wetter and milder maritime climate than elsewhere in the Klamath Mountains (78). 48 82 78f 78d. 1 3 5 Sierra Nevada 33 East Central Texas Plains and Uplands Ecology), and Jeffrey A. Comstock (Indus Corporation). Unlike the purely mountainous terrain of the Inland Siskiyous (78e) or the broader Rogue/Illinois Valleys (78a), the Productive forests composed of tanoak, Douglas-fir, and some Port Orford cedar cover its mountainous landscape; tanoak is 4 11 42 6 Southern and Central California 34 Western Gulf Coastal Plain 61 Erie Drift Plain 78c 16 Umpqua Interior Foothills ecoregion is a complex of foothills and narrow valleys containing fluvial terraces and more common than elsewhere in Oregon. Broadleaf evergreens, such as tanoak and madrone, quickly colonize disturbed areas, 17 43 50 58 58 Chaparral and Oak Woodlands 35 South Central Plains 62 North Central Appalachians 51 COLLABORATORS AND CONTRIBUTORS: Thomas Atzet (USFS), Hugh 46 50 63 Middle Atlantic Coastal Plain floodplains. Ecoregion 78c is drier than the foothills of the Willamette Valley (3d) partly because the summer Pacific high pressure making it difficult to regenerate conifer forest growth. Xeric soils derived from Siskiyou rock types are characteristic; udic soils which 9 17 7 Central California Valley 36 78 80 83 59 8 Southern California Mountains 37 Valley 64 Northern Barrett (U.S. Department of Interior, Bureau of Land Management), Rick Hafele system arrives earlier and remains longer than in ecoregions to the north. Summers are hot and dry, and soils have a xeric moisture support western hemlock and Sitka spruce are much less common than in the wetter Coast Range (1). 12 17 57 60 58 52 53 65 Southeastern Plains 56 62 9 Eastern Cascades Slopes and 38 (Oregon Department of Environmental Quality), Charles Johnson (USFS), Thomas regime in contrast to the udic soils of the Mid-Coastal Sedimentary ecoregion (1g) to the west. Oregon white oak woodland, Douglas- The Klamath River Ridges have a dry, continental climate. Vegetation varies with slope, aspect, and elevation. Higher 18 62 Foothills 39 Ozark Highlands 66 Blue Ridge 44 47 78g 57 61 67 67 Ridge and Valley Loveland (USGS), Robert Meurisse (USFS, retired), Chad L. McGrath (NRCS), fir, ponderosa pine, madrone, and an understory chaparral community cover the slopes and intermingle with pastureland, vineyards, altitudes and north-facing slopes have Douglas-fir and white fir; lower elevations and south-facing slopes are covered in Mine tailings continue to impact water quality and 5 19 84 10 Columbia Plateau 40 Central Irregular Plains 54 64 Steep terrain, a dry climate, and competition from shrubby chaparral species complicates stream habitat in the Klamath Mountains (78). 13 11 Blue Mountains 41 Canadian Rockies 68 Southwestern Appalachians and Robert Ottersberg (Cordilleran Services, Inc.). orchards, and row crops. 55 70 reforestation following logging in the Inland Siskiyous (78e). ponderosa pine and western juniper, species that are more drought resistant than other vegetation types found in Ecoregion 78. 21 40 63 69 Central Appalachians 1 7 20 25 12 Snake River Plain 42 Northwestern Glaciated Plains 70 Western Allegheny Plateau 27 66 13 Central Basin and Range 43 Northwestern Great Plains REVIEWERS: Sharon E. Clarke (Oregon State University), Robert M. Hughes 6 72 69 14 Mojave Basin and Range 44 Nebraska Sand Hills 71 28 40 71 (Dynamac Corporation), and Michael A. Bollman (Dynamac Corporation). 15 Northern Rockies 45 Piedmont 72 Interior River Valleys and Hills 14 39 8 16 Idaho Batholith 46 Northern Glaciated Plains 73 Mississippi Alluvial Plain 8 0 . N o r t h e r n B a s i n a n d R a n g e 22 68 65 CITING THIS POSTER: Thorson, T.D., Bryce, S.A., Lammers, D.A., Woods, A.J., 26 38 66 17 Middle Rockies 47 74 Mississippi Valley Loess Plains 6 45 Omernik, J.M., Kagan, J., Pater, D.E., and Comstock, J.A., 2003. Ecoregions of Ecoregion 80 contains dissected lava plains, rolling hills, alluvial fans, valleys, and scattered mountains. Overall, it is higher and cooler than the Snake River Plain (12) and has more available moisture and a cooler climate than the Central Basin and Range (13). Potential natural 37 18 Wyoming Basin 48 Lake Agassiz Plain 75 Southern Coastal Plain 81 23 67 36 73 63 19 Wasatch and Uinta Mountains 49 Northern Minnesota Wetlands 76 Southern Florida Coastal Plain Oregon (color poster with map, descriptive text, summary tables, and photographs): vegetation is sagebrush steppe; cool season grasses, such as Idaho fescue and bluebunch wheatgrass are more common than in Ecoregion 13. Juniper-dominated woodland occurs on rugged, stony uplands. Most of Ecoregion 80 is used as rangeland. Cropland is found locally, 25 20 Colorado Plateaus 50 Northern Lakes and Forests 77 North Cascades Reston, Virginia, U.S. Geological Survey (map scale 1:1,500,000). but, in general, soils are less suitable for agriculture than those in the Columbia Plateau (10) and the Snake River Plain (12). In Oregon, the western two-thirds of Ecoregion 80 is internally-drained. 79 23 29 21 Southern Rockies 51 North Central Hardwood 78 Klamath Mountains 74 27 32 35 65 22 Arizona/New Mexico Plateau Forests 79 Madrean Archipelago This project was partially supported by funds from the USEPA–Office of Research The nearly level to undulating Dissected High Lava Plateau is underlain by basalt and cut by shear-walled canyons. lakes (80d and 80e). The vegetation is sagebrush steppe; bunchgrasses, including bluebunch wheatgrass, are generally associated with 24 80a 33 23 Arizona/New Mexico Mountains 52 80 Northern Basin and Range and Development's Environmental Monitoring and Assessment Program through Potential natural vegetation is mostly sagebrush steppe but scattered juniper woodlands grow on rocky uplands. Streams Wyoming big sagebrush except in overgrazed areas where they have been depleted and replaced by cheatgrass. 30 73 24 Chihuahuan Deserts 53 Southeastern Wisconsin Till 81 Sonoran Basin and Range contract 68-C6-005 to Dynamac Corporation. Partial funding was also provided by drain to the Snake River; in contrast, the High Lava Plains (80g) and the Central Basin and Range (13) are internally-drained. The Semiarid Uplands ecoregion includes scattered hills, low mountains, and buttes. Elevations vary from 4,800 to 7,500 25 Western High Plains 82 Laurentian Plains and Hills 34 75 Plains 83 Eastern Great Lakes and Hudson the Oregon Watershed Enhancement Board. Intermittent lakes occur but are much less common than in Ecoregion 80g. Ecoregion 80a is primarily rangeland and wildlife habitat. 80j feet. Moisture levels are high enough to support woodland. Ecoregion 80j is largely covered by juniper steppe woodland on 31 26 Southwestern Tablelands 54 Central Corn Belt Plains 27 Central Great Plains 55 Eastern Corn Belt Plains Lowlands The Pluvial Lake Basins contained vast lakes during the Pleistocene epoch, but, today, they do not seasonally collect water rocky soils and sagebrush steppe or Idaho fescue on more finely textured soils. The density and extent of juniper varies over time and Digital information can be obtained at http://www.epa.gov/wed/pages/ecoregions/ Sagebrush and grass associations, juniper The High Desert Wetlands (80e) provide critical 76 28 56 Southern Michigan/Northern 84 Atlantic Coastal Pine Barrens 80d as extensively as the High Desert Wetlands (80e). The dry lake beds near the Cascade Mountains have a significant ash layer is dependent on climate, grazing pressure, and fire suppression. Indiana Drift Plains ecoregions.htm. woodland, and basalt rimrock are typical of the habitat for waterfowl and wading birds, such as the present. Sagebrush dominates with associated grasses. The land is used for rangeland and sprinkler-irrigated alfalfa farming. The Partly Forested Mountains ecoregion is represented in Oregon by the higher elevations of . On Steens transition between Ecoregions 80a, 80g, and 80j. white pelican and stilt. Photo: NOAA Map Source: USEPA, 2003 The nearly level High Desert Wetlands ecoregion provides critical habitat for nesting and migratory birds as well as 80k Mountain, above the juniper woodland zone (Ecoregion 80j), the landscape is almost treeless; broad areas of mountain big 80e associated upland birds and mammals. Its fine-textured soils are poorly-drained and basins collect water seasonally. sagebrush alternate with scattered groves of aspen. Deep, glacial U-shaped valleys radiate from the summit. Alpine areas were Although water levels fluctuate from year to year, lakes and wetlands hold water more consistently than on the coarser, better drained seriously eroded following intense grazing by domestic sheep in the late 19th century. soils of the Pluvial Lake Basins (80d). Sedges, rushes, black greasewood, tufted hairgrass, and creeping wildrye occur in wetter areas. The arid Salt Shrub Valleys were once inundated by Pleistocene lakes. Nearly flat basin floors are extensive and wetlands, The Owyhee Uplands and Canyons ecoregion is a sagebrush steppe containing deep river canyons, barren lava fields, 80l terraces, dunes, and alluvial fans also occur. Characteristically, the basin floors have strongly saline and very alkaline soils 80f badlands, and tuffaceous outcrops that are riddled by caves. Though Ecoregion 80f's climate and vegetation are similar to the that support black greasewood, inland saltgrass, shadscale, and bud sagebrush. Soils, climate, and vegetation are transitional to the Dissected High Lava Plateau (80a), its lithology is more varied, stream density is higher, and water availability is greater than in Central Basin and Range (13) and Lahontan Salt Shrub Basin (13j) to the south. Rangeland and irrigated agriculture occur. Fault block mountains, broad expanses of sagebrush, and alkaline playas characterize the landscape Ecoregion 80a. These attributes, combined with its remote location, make Ecoregion 80f a particularly valuable refuge for wildlife. The Barren Playas ecoregion includes the playas and sand dunes of Summer Lake, Silver Lake, and the Alvord Desert, of the Northern Basin and Range (80), although the mountain ranges and associated playas are far The vast, nearly level to undulating High Lava Plains ecoregion is shrub- and grass-covered and contains scattered volcanic 80m three of the most arid areas in Oregon. On the playas, lake levels and salinity fluctuate seasonally and yearly. Surface fewer in number than those in the Central Basin and Range ecoregion (13) to the south. 80g cones and buttes. Ecoregion 80g is internally-drained in contrast to Ecoregion 80a, and, as a result, it lacks anadromous fish The fault scarp of Steens Mt. (80k) chops Leslie Gulch in Ecoregion 80f has colorful Photo: Sharon Clarke, OSU material is clayey, saline, alkaline, and poorly-drained. Ecoregion 80m is more barren than the Salt Shrub Valleys (80l); vegetation, runs. Ecoregion 80g also differs from the Dissected High Lava Plateau (80a) in having numerous intermittent precipitously into the Alvord Desert (80l and tuffaceous deposits that are riddled with caves . where present, is sparse and composed of salt-tolerant plants. Ecoregion 80m is nonarable and used for recreation and wildlife habitat. 80m). Photo: Scott Moore, BLM