Summary Table: Characteristics of the Ecoregions of 1 8 . WYOMING BASIN 2 2 . ARIZONA/NEW MEXICO PLATEAU Level IV Ecoregions Physiography Geology Soils Climate Natural Vegetation Land Use and Land Cover Level IV Ecoregions Physiography Geology Soils Climate Natural Vegetation Land Use and Land Cover Area Elevation/ Surfi cial and Bedrock Order (Great Group) Common Soil Series Temperature/ Precipitation Frost Free Mean Temperature Area Elevation/ Surfi cial and Bedrock Order (Great Group) Common Soil Series Temperature/ Precipitation Frost Free Mean Temperature (square Local Relief Moisture Regimes Mean annual Mean annual January min/max; (square Local Relief Moisture Regimes Mean annual Mean annual January min/max; miles) (feet) (inches) (days) July min/max (oF) miles) (feet) (inches) (days) July min/max (oF) 18a. Rolling 2197 Rolling plains with hills, cuestas, 5200-7500/ Quaternary alluvium, colluvium, outwash, Aridisols (Haplargids, Ryan Park, Maybell, Frigid/ Mostly 60-90 4/32; Sagebrush steppe with areas of bitterbrush Shrub-covered rangeland, with some 22a. San Luis 993 Low mountains, hills, mesas, and 7900-9100/ Quaternary gravels and alluvium. Tertiary Aridisols (Haplocalcids, Travelers, Garita, Luhon, Frigid/ 10-14 30-60 4/32; Shrublands, grasslands, and pinyon-juniper Shrub- and grass-covered rangeland. Sagebrush mesas, terraces, and near the footslopes, 100-400 thin residuum, and eolian deposits. Tertiary Calciargids), Entisols Rockriver, Mayspring, Ryark, Aridic, Ustic 10-15, 48/88 shrubland and scattered juniper woodland areas of cropland, especially along Shrublands and foothills. 400-1000 igneous rocks of basalt fl ows, pre-ash Calciargids), Mollisols Space City, Costilla, Tolman, Aridic, Ustic 42/76 woodlands at highest elevations. Species Low density grazing, wildlife Steppe alluvial fans, and outwash fans. and Cretaceous claystone, sandstone, and (Torripsaments), Berlake, Taffi m, Styers, up to 20 at higher elevations. Associated vegetation the Yampa River. Crops include hay, Hills fl ow andesitic lavas, breccias, tuffs, and (Argiustolls) Bendire, Curecanti, Rock include big sagebrush, rubber rabbitbrush, habitat. other sedimentary rock. Areas of lenticular Mollisols (Argiustolls), Ruedloff, Tresano at higher may include western wheatgrass, needle- wheat, barley, and oats. Oil, gas, and conglomerates. River, Stunner, Hesperus winterfat, western wheatgrass, green coal, oil shale, and marlstone. Rock outcrops Vertisols (Haplusterts) elevations and-thread, blue grama, Sandberg bluegrass, coal production. needlegrass, blue grama, and needle-and- occur. Junegrass, rabbitbrush, fringed sage, Wyoming thread. big sagebrush, silver and black sagebrush in 22b. San Luis Alluvial 1217 Irregular plains. Wetlands, springs, and 7500-8000/ Quaternary alluvium of gravel, sand, and silt. Mollisols (Argiaquolls, Graypoint, Platoro, Dunul, Frigid/ 6-10 60-90 0/34; Shrublands dominated by shadscale, fourwing Irrigated cropland has replaced most lowlands, and mountain big sagebrush at the areas with a high water table. Few large 10-100 Endoaquolls, San Arcacio, Zinzer, Acacio, Aridic, 46/80 saltbush, and greasewood. of the natural vegetation. Crops higher elevations. Flats and Wetlands perennial streams which originate in Calciustolls), Aridisols Alamosa, Lajara, Vastine, Aquic, Ustic include potatoes, alfalfa, barley, hay, mountains. (Haplargids, Natrargids), Gunbarrel, Mosca, San Luis and wheat. Small areas of vegetables 18d. Foothill 248 Footslopes, alluvial fans, hills, low 6000-9600/ Quaternary alluvium and colluvium Alfi sols (Glossocryalfs), Uinta, Miracle, Chittum, Cryic/ 10-20 60-90 8/34; Big sagebrush shrubland, with pinyon- Shrub-covered rangeland and Entisols (Torriorthents, such as lettuce, spinach, and carrots. Shrublands and mountains, ridges, and valleys. 200-1000 derived from Tertiary sedimentary and Mollisols (Argicryolls), Rentsac Ustic, Xeric 54/84 juniper woodland. Higher elevations may wildlife habitat. Psammaquents) Low Mountains older crystalline rocks of the surrounding Inceptisols (Calciustepts) have areas of lodgepole pine, aspen, and 22c. Salt Flats 866 Irregular plains and alkaline basins. 7400-7700/ Quaternary alluvium of gravel, sand, and silt. Entisols Space City, Costilla, Cotopaxi, Frigid/ 6-8 60-90 0/34; Shrublands dominated by shadscale, fourwing Shrub-covered rangeland with low mountains. Tertiary claystone, mudstone, subalpine fi r. Associated vegetation may 10-100 (Torripsamments), Hooper, San Luis, Corlett Aridic 46/80 saltbush, greasewood, horsebrush, spiny density grazing, wildlife habitat, sandstone, and oil shale. Precambrian include rabbitbrush, mountain big sagebrush, Aridisols (Natrargids) hopsage, rubber rabbitbrush, saltgrass, and and some small areas of irrigated quartzite, conglomerate, and shale. pricklypear, bluebunch wheatgrass, and Idaho alkali sacaton. cropland. fescue on fi ne-textured soils. Rocky Mountain juniper, Utah juniper, and mountain mahogany 22e. Sand Dunes and 254 Large dunes, low parabolic and 7500-8900/ Quaternary eolian sand deposits, dunes, and Entisols Cotopaxi, Space City, Costilla, Frigid/ 8-12 60-90 0/34; Sand sagebrush, rubber rabbitbrush, sand Bare sand, shrublands, grasslands. woodlands occur on rock outcrops. Sand Sheets longitudinal shrub-stabilized dunes, and 100-700 sand sheets. (Torripsamments), Alamosa, Lajara, Vastine Aridic 44/80 dropseed, sand verbena, prairie sunfl ower, Recreation, some low density sand sheets. Mollisols (Endoaquolls, and spiny hopsage on sand sheets. Dune areas rangeland on vegetatively stabilized 18e. Salt Desert Shrub 718 Plains, nearly level fl oodplains and 5400-7300/ Quaternary alluvium and colluvium; Entisols (Torriorthents), Luhon, Brownsto, Niart, Frigid, 8-15 60-90 6/32; Desert shrublands dominated by alkaline- Shrub-covered rangeland and Argiaquolls), Aridisols are mostly devoid of vegetation, some Indian sand sheets. Wildlife habitat. Basins terraces, and rolling alluvial fans. 50-300 gravel and fan deposits; areas of active and Aridisols (Haplocalcids), Rentsac, Atchee, Mikim, Mesic/ 50/88 tolerant shrubs and grasses: greasewood, wildlife habitat. Oil and gas (Haplocalcids) ricegrass, blowout grass, and lemon scurfpea. Streams are ephemeral or intermittent; stabilized dune sand and loess. Tertiary and Mollisols (Calciustolls), Huguston, Teagulf Ustic, Aridic Gardner’s saltbush, fourwing saltbush, production. many are incised and fl ow into playas. Cretaceous siltstone, sandstone, claystone, Inceptisols (Calciustepts) shadscale, bud sage, and big sagebrush. Substrates are fi ne textured material and areas of oil shale and marlstone. Stabilized sand dunes are dominated by alkali or platy shale gravels. Seasonal playas cordgrass, Indian ricegrass, blowout grass, have high levels of soluble salts. alkali wildrye, and needle-and-thread. 2 5 . HIGH PLAINS 18f. Laramie Basin 116 High elevation valley, nearly fl at 7800-9100/ Quaternary alluvium and colluvium. Tertiary Mollisols (Argicryolls, Driggs, Newfork, Cryic/ 15-20 60-90 4/30; Mixedgrass prairie with needle-and-thread, Grassland and shrubland. Rangeland, Level IV Ecoregions Physiography Geology Soils Climate Natural Vegetation Land Use and Land Cover fl oodplains, and low terraces. Streams 100-300 gravels and fan deposits in stream and Cryaquolls, Pendergrass, Clergern Xeric, Ustic 40/76 western wheatgrass, blue grama, Indian seasonal grazing, some hay Area Elevation/ Surfi cial and Bedrock Order (Great Group) Common Soil Series Temperature/ Precipitation Frost Free Mean Temperature and rivers are moderate gradient, with fl oodplain areas. Tertiary shale, siltstone, and Haplocryolls), Inceptisols ricegrass, and other mixedgrass species, along production. (square Local Relief Moisture Regimes Mean annual Mean annual January min/max; cobble, gravel, and sandy substrates. conglomerate. Triassic and Permian siltstone, (Eutrocryepts) with rabbitbrush, fringed sage, and various forb miles) (feet) (inches) (days) July min/max (oF) shale, and sandstone. and shrub species. 25b. Rolling Sand 4620 Undulating plains with areas of active 3500-5100/ Quaternary eolian sand sheets and dunes. Entisols Valent, Vona, Julesburg, Mesic/ 12-20 140-160 14/42; Sandsage prairie: sand sagebrush, sand Grassland and rangeland with some Plains sand dunes. Few perennial streams. 25-150 Underlain by Tertiary claystones and (Torripsamments), Haxtun, Jayem, Busher, Bijou Aridic, Ustic 60/92 bluestem, prairie sandreed, blowout grass, areas of irrigated cropland. Drainage network is not well established sandstones of the Ogallala Formation. Alfi sols (Haplustalfs), lemon scurfpea, little bluestem, rabbitbrush, due to a lack of runoff and sand-choked Mollisols (Argiustolls, Indian ricegrass, and sand dropseed. drainage ways. Disappearing Haplustolls), Aridisols 2 0 . COLORADO PLATEAUS subterranean streams. (Haplargids) 25c. Moderate Relief 6206 Irregular plains with moderate slope. 3600-6500/ Quaternary loess, sandy, gravelly, and loamy Mollisols (Argiustolls, Olney, Ascalon, Platner, Mesic/ 12-18 140-160 14/44; Shortgrass prairie: blue grama, buffalograss, Grassland and rangeland with areas Level IV Ecoregions Physiography Geology Soils Climate Natural Vegetation Land Use and Land Cover Plains Intermittent streams, with a few 50-200 alluvium, and some thin residuum. Tertiary Paleustolls, Haplustolls), Stoneham, Nucla, Kim, Dix, Ustic, Aridic 60/92 with threadleaf sedge, fringed sage, Junegrass, of dryland and irrigated agriculture. Area Elevation/ Surfi cial and Bedrock Order (Great Group) Common Soil Series Temperature/ Precipitation Frost Free Mean Temperature large perennial streams which mostly claystone, sandstone, and conglomerate, Alfi sols (Haplustalfs), Altvan, Keith, Kuma, Ulysses, and western wheatgrass. Riparian areas contain Gas and oil production. (square Local Relief Moisture Regimes Mean annual Mean annual January min/max; originate in higher relief areas. Silty including the Tertiary Ogallala Formation Aridisols (Haplargids), Colby, Norka cottonwood/shrub/herbaceous species. miles) (feet) (inches) (days) July min/max (oF) and sandy substrates. Small, open, in the east. Cretaceous shales, sandstones, Entisols (Torriorthents) 20a. Monticello- 951 Nearly level to rolling plains and basins 6000-7300/ Quaternary colluvium, alluvium, and Aridisols (Calciargids, On uplands: Witt, Sharps, Mesic/ 10-15 90-120 12/38; Sagebrush steppe and associated grasses, with Dryland cropland with some areas depressional wetland “playas” scattered claystones, and coal beds in the west. throughout region. Cortez Uplands containing stream terraces, alluvial fans, 25-200 eolian deposits. Western area underlain by Natrargids), Alfi sols Cahona, Lazear, Pulpit. Aridic, Ustic 52/88 scattered pinyon-juniper woodland. Dominant of irrigated cropland, shrubland, and Sagebrush and low rolling hills and ridges. Cretaceous Dakota sandstone formation. (Haplustalfs), Entisols In valleys: Falfa, Arboles, species include: Wyoming big sagebrush, and rangeland. Crops include pinto Eastern areas underlain by Cretaceous Cliff (Torriorthents), Vertisols Bayfi eld, Uzona western wheatgrass, and Indian ricegrass. beans, Anasazi beans, winter wheat, Valleys House and Pictured Cliffs sandstone and (Haplusterts) Some two-needle pinyon pine, bitterbrush, and and alfalfa. Lewis shale, or Tertiary arkosic sandstone, serviceberry. 25d. Flat to Rolling 13219 Flat to rolling plains. Intermittent 3600-5700/ Quaternary loess, alluvial deposits, and some Mollisols (Argiustolls, Stoneham, Fort Collins, Mesic/ 12-18 140-180 16/46; Shortgrass prairie: blue grama, buffalograss, Dryland and irrigated cropland with siltstone, and shale. Plains streams, with a few large perennial 10-150 thin residuum. Tertiary gravel, claystone, Paleustolls, Haplustolls), Olney, Richfi eld, Keith, Colby, Ustic, Aridic 62/94 with threadleaf sedge, fringed sage, Junegrass, winter wheat, grain sorghum, corn, streams. Silty and sandy substrates. sandstone, and sand deposits, including the Alfi sols (Haplustalfs), Wages, Rosebud, Manter, and western wheatgrass. Riparian areas contain barley, sunfl owers, and sugar beets 20b. Shale Deserts 2923 Nearly level to rolling plains and basins, 4900-8000/ Quaternary colluvium, alluvium, and eolian Entisols (Torriorthents), Bulkley, Evanston, Forelle, Frigid, 8-15 90-150 6/36; Sparse cover of mat saltbush shrubland and Shrubland and rangeland, areas of Small, open, depressional wetland Ogallala Formation in the east. Cretaceous Entisols (Ustorthents, Ascalon, Platner, Haxtun, cottonwood/shrub/herbaceous species. (grown under irrigation). Some and Sedimentary with benches, low rounded hills, and 25-400 deposits. Cretaceous Mancos shale (northwest Aridisols (Haplargids, Paradox, Diamondville, Mesic/ 48/92 salt desert scrub: shadscale, Nuttall’s saltbrush, dryland and irrigated cropland with “playas” scattered throughout region. shales, sandstones, claystones, and coal beds Torriorthents) Rago, Alliance, Canyon, Weld, grassland and rangeland. Gas and oil Basins badlands. of Rangley, east of Meeker, Grand Valley, Calciargids), Inceptisols Rock River, Persayo, Farb, Aridic, Ustic blackbrush, fourwing saltbush, Wyoming big winter wheat, small grains, forage in the west. Norka, Adena production, especially in the Dry Creek Basin, Disappointment Valley, (Calciustepts), Redlands, Hagerman, Palma, sagebrush, desert trumpet, galleta grass, and crops, and pinto beans. Orchards of Basin. and in the southwest, just north of the Vertisols (Haplusterts), Transfer, Callan, Skein, other associated grasses. Floodplain areas apples, peaches, pears, and apricots Mancos River). Tertiary claystone, siltstone, Mollisols (Argiustolls, Chipeta, Uncompahgre support greasewood, alkali sacaton, seepweed, in the Gunnison and Colorado mudstone, shale and sandstone (areas west Endoaquolls) and shadscale. Badland areas have little to no River valleys. Shrublands provide of Meeker, and in the Colorado River valley vegetation cover. important winter habitat for wildlife. 25l. Front Range 782 Fans, irregular plains, and scattered 4800-5300/ Quaternary gravel and sandy alluvium, eolian Mollisols (Argiustolls), Altvan, Ascalon, Larimer, Mesic/ 14-18 120-140 12/40; Shortgrass and mixedgrass prairie: blue Urban and residential, some irrigated outside of Rifl e). Jurassic and Triassic shale Fans low hills. Intermittent and perennial 50-200 sand deposits. Underlain by sandstone, Aridisols (Haplargids), Stoneham, Dacono, Nunn, Ustic, Aridic 56/88 grama, needle-and-thread, western wheatgrass, cropland with hay, corn, wheat, and and siltstone, salt anticlines (Paradox Valley, streams with gravelly, silty, and sandy claystone, and shale of the Cretaceous Alfi sols (Haplustalfs), Renohill, Shingle, Otero, buffalograss, Junegrass, and little bluestem. barley. Many manmade lakes and Big Gypsum Valley). substrates. Streams are generally colder Laramie and Fox Hills formations and Entisols (Torriorthents) Thedalund, Olney, Ulm, Big bluestem is scattered in low concentrations gravel pits. and may contain species found more sandstone, mudstone, claystone, and Englewood, Nederland, Kutch, throughout the region. Riparian areas contain 20c. Semiarid 9079 Benches, mesas, cuestas, alluvial fans, 5400-9200/ Quaternary alluvium and colluvium. Entisols (Torriorthents), Atchee, Cahona, Hagerman, Mesic, Mostly 60-120 8/40; Pinyon-juniper woodland, Gambel oak Woodland and shrubland. Rangeland, commonly in the Southern Rockies (21). conglomerate of the Tertiary Denver and Denver cottonwood/shrub/herbaceous species. Benchlands and hillslopes, cliffs, arches, and canyons. A 100-1000 Tertiary and Cretaceous siltstone, sandstone, Alfi sols (Haplustalfs), Lamphier, Lazear, Mikim, Frigid; Cryic 10–18, 48/88 woodland, and sagebrush steppe with black recreation, coal mining, oil and gas Arapahoe formations to the south. Canyonlands few isolated peaks. Areas of low relief claystone, oil shale, and marlstone. In deep Mollisols (Argiustolls, Palma, Persayo, Redcreek, on highest on highest sagebrush, winterfat, Mormon tea, fourwing production. Oil shale extraction. alternate with areas of high relief. canyons and cliffs: areas of Permian siltstone, Haplustolls, Argicryolls, Rentsac, Shavano, Skein, elevations/ sites 20-25 saltbush, shadscale, galleta grass, and blue sandstone, and shale, and Pre-Pennsylvanian Haplocryolls), Aridisols Skyway, Transfer, Utaline, Aridic, Ustic grama. Paleozoic shale, limestone, and sandstone. (Haplargids, Calciargids, Veatch, Zyme, Callan, Castner, Haplocambids, Chipeta, Cochetopa 2 6 . SOUTHWESTERN TABLELANDS Haplocalcids), Inceptisols (Calciustepts) Level IV Ecoregions Physiography Geology Soils Climate Natural Vegetation Land Use and Land Cover Area Elevation/ Surfi cial and Bedrock Order (Great Group) Common Soil Series Temperature/ Precipitation Frost Free Mean Temperature 20d. Arid 70 Narrow canyons, cliffs, valley fl oors, 4900-6000/ Quaternary alluvium and colluvium. Entisols (Torriorthents), Claysprings, Myton, Uzona, Mesic/ 8-10 120-150 18/40; Desert shrubland: blackbrush, shadscale, Indian Shrubland. Recreation, rangeland, (square Local Relief Moisture Regimes Mean annual Mean annual January min/max; o Canyonlands fl oodplains, structural benches, mesas, 200-500 Cretaceous sandstone, shale, and Aridisols (Natrargids) Tocito Aridic 60/92 ricegrass, fourwing saltbush, blue grama, mat and wildlife habitat. miles) (feet) (inches) (days) July min/max ( F) and cuestas. Terrain deeply eroded by conglomerate. Rock outcrops are common. saltbush, saline wildrye, and galleta grass. 26e. Piedmont Plains 13373 Irregular and dissected plains. 3600-6500/ Quaternary alluvium and eolian deposits Alfi sols (Haplustalfs), Wiley, Baca, Colby, Manvel, Mesic/ Mostly 120-160 14/46; Shortgrass prairie: blue grama, green Mostly grass-covered rangeland with major rivers and their tributaries. and Tablelands Intermittent streams, with a few 50-200 of loess, silt, and sand. Cretaceous shale, Mollisols (Argiustolls, Minnequa, Penrose, Rocky Ustic, Aridic 12-16, 60/92 needlegrass, buffalograss, needle-and-thread, scattered areas of dry and irrigated 20e. Escarpments 1013 High, dissected cliffs, escarpments, 6000-9000/ Quaternary alluvium and colluvium. Tertiary Entisols (Torriorthents), Claysprings, Myton, Uzona Mesic/ Mostly 60-90 4/36; Pinyon-juniper woodland, mountain mahogany, Shrubland, evergreen and deciduous large perennial streams which mostly limestone, and sandstone. Paleustolls), Entisols Ford, Nepesta, Ascalon, Fort with 10-12 and red threeawn. Also may include mixed cropland. Dryland agriculture is mesa tops, and breaks with a wide 500-3000 and Cretaceous sandstone, shale, siltstone, Aridisols (Natrargids) Aridic 15-25, 46/84 aspen, and Douglas-fi r forest at highest woodland, some forests. Recreation originate in mountains or higher relief (Torriorthents), Aridisols Collins, Stoneham, Kim, in low- grass species such as western wheatgrass, mostly to the north of the Arkansas elevational range. Includes the Book marlstone, limestone, and areas of oil shale. up to 32 elevations. and wildlife habitat, some limited areas. Silty and sandy substrates. (Haplargids, Natrargids, Razor, Midway, Limon, lying area galleta grass, sand dropseed, and little River. Cliffs and Roan Cliffs. Rock outcrops are common. at higher grazing. Haplocalcids) Deertrail, Absted, Harvey, between bluestem. Sand sagebrush, yucca and cholla elevations Truckton, Yoder, Blakeland, Pueblo cactus can also occur. Ordway, Cadoma, Campo, and Las 20f. Uinta Basin Floor 39 Synclinal basin containing mountain- 5500-6100/ Quaternary colluvium, alluvium, and eolian Mollisols (Haplustolls), Potts, Walknolls, Veatch, Mesic/ 8-10 90-120 6/34; Desert shrubland: saltbush, greasewood, Shrubland. Rangeland, cropland, Platner Animas fed streams, alluvial terraces, outwash 50-200 deposits. Tertiary and Cretaceous sandstone Entisols (Torriorthents), Redcreek, Castner Aridic 56/88 shadscale, Indian ricegrass, galleta grass, and wildlife habitat. Oil and gas 26f. Mesa de Maya/ 565 Broad mesa, knobs, and dissected plains 4500-6200/ Quaternary alluvium and colluvium. Capping Mollisols (Argiustolls, Capulin, Torreon, Apache, Mesic/ 14-18 100-150 16/46; Pinyon-juniper woodland and shortgrass Woodland, rangeland, grassland, and terraces, fl oodplains, hills, and ridges. and shale. Aridisols (Haplargids, Wyoming big sagebrush, fourwing saltbush, production. Black Mesa with deep canyons. Rough, rocky, steep 75-500 the mesa: Tertiary basalt, 60 to 70 feet thick. Haplustolls), Entisols Travessilla, Carnero, Ustic, Aridic 58/90 prairie. On top of the mesa: shortgrass prairie wildlife habitat. Haplocalcids) winterfat, needle-and-thread. slopes are common. Cretaceous sandstone and shale. On slopes (Torriorthents), Aridisols Fruitland, Manzano, Alicia, dominated by blue grama, hairy grama, and exposed canyons: Jurassic sandstone, (Haplocambids) Kim. Rock outcrops. sideoats grama, galleta grass, buffalograss, claystone, mudstone, and limestone, Triassic and western wheatgrass. On rocky slopes sandstone, siltstone, and limestone. and in canyons: juniper with pinyon pine- oak woodlands with a few isolated areas of 2 1 . SOUTHERN ROCKIES mesquite shrublands. Level IV Ecoregions Physiography Geology Soils Climate Natural Vegetation Land Use and Land Cover Area Elevation/ Surfi cial and Bedrock Order (Great Group) Common Soil Series Temperature/ Precipitation Frost Free Mean Temperature 26g. Purgatoire Hills 1041 Dissected plains and tablelands with 4900-7400/ Quaternary alluvium and colluvium. Entisols (Torriorthents), Travessilla, Baca, Manvel, Mesic/ 12-16 100-150 14/46; Juniper woodlands and shortgrass prairie. Woodland and wildlife habitat. (square Local Relief Moisture Regimes Mean annual Mean annual January min/max; some hills, steep canyons, and rock 100-700 Cretaceous sandstone and shale. Jurassic Alfi sols (Haplustalfs) Minnequa, Penrose Ustic, Aridic 58/90 Rocky Mountain juniper, oneseed juniper, Utah o and Canyons miles) (feet) (inches) (days) July min/max ( F) outcrops. sandstone, claystone, and shale. Triassic juniper, blue grama, and buffalograss. 21a. Alpine Zone 3690 Glaciated. High mountains with steep 10000- Quaternary rubble, glacial drift, and Inceptisols Mirror, Bross, Whitecross, Cryic/ 35-70+ Less -8/24; Alpine meadows. Dominated by bistort, alpine Snow, ice, bare rock, alpine sandstone and siltstone. Permian siltstone, slopes, ridges, and exposed rocky peaks 14400+/ colluvium. Exposed bedrock. Tertiary (Dystrocryepts) Henson, Teewinot Udic Deep winter than 30 36/72 timothy, alpine avens, alpine bluegrass, alpine meadows. Recreation and wildlife dolomite, and sandstone. above timberline. Some wetlands and 400-2500+ andesitic lavas, basalts, breccia, tuffs, and snowpack clover, tufted hairgrass, and various sedges. habitat. Snowmelt provides water 26h. Pinyon-Juniper 997 Dissected plains and tablelands with 5100-7100/ Quaternary alluvium and colluvium. Entisols (Torriorthents), Travessilla, Baca, Noden, Mesic, 12-20, 90-120 16/44; Pinyon-juniper woodlands: pinyon pine, Woodland and wildlife habitat. glacial lakes. High gradient headwater conglomerates. Precambrian metasedimentary Trees if present are krummholz (dwarf and/or source to lower-elevation ecoregions. Woodlands and some scattered ridges and hills. 100-500 Cretaceous shale, limestone, and sandstone. Alfi sols (Haplustalfs), Bond, Razor, Midway, Limon, Frigid/ with 56/88 Rocky Mountain juniper, eastern redcedar, and streams with boulder, cobble, and rocks: pelitic schist, amphibole schist, prostrate shrubs) and include spruce, fi r, and Savannas Mollisols (Argiustolls), Manvel, Minnequa, Penrose, Ustic, Aridic highest oneseed juniper. bedrock substrates. quartzite, diamictite, quartz-pebble pine. Willow thickets occur in depressions and Aridisols (Haplargids) Wetmore (in west at the base near the conglomerate, and marble. Permian and Pre- wet meadows. of mountains). Rock outcrops. mountains Pennsylvanian Sangre de Cristo Formation: arkosic conglomerate, sandstone, and 26i. Pine-Oak 580 Dissected plains and hills. 6000-7500/ Quaternary alluvium and colluvium. Tertiary Mollisols (Argiustolls, Brussett, Peyton, Kettle, Weld, Frigid, 14-20 90-120 10/36; Pine-oak woodlands and foothill grasslands. Woodland, grassland, rangeland, and siltstone. Woodlands 100-300 and Cretaceous arkosic conglomerate, Paleustolls), Alfi sols Fondis, Bresser Mesic/ 50/80 Ponderosa pine, Gambel oak, mountain wildlife habitat. Increasing urban and sandstone, claystone, and shale. (Haplustalfs) Ustic mahogany, skunkbush, western serviceberry, residential development. 21b. Crystalline 4737 Glaciated. High mountains with steep 8500-10000 Quaternary glacial till and colluvium. Alfi sols (Glossocryalfs, Boyle, Granile, Kebler, Cryic, Frigid/ 30-58 30-60 -4/28; Subalpine forests dominated by Engelmann Evergreen and some deciduous and chokecherry. Gambel oak often forms a Subalpine Forests slopes. High gradient perennial streams in the north, Tertiary intrusive rocks. Precambrian Haplocryalfs), Lakehelen, Leadville, Limber, Udic, Ustic Deep 36/72 spruce and subalpine fi r. Often interspersed forest. Timber production, well developed understory in the Ponderosa with boulder, cobble, and bedrock 9000-12000 metasedimentary, metavolcanic, and Mollisols (Argiustolls, Lucky, Peeler, Resort, Seitz winter with aspen groves, lodgepole pine forest, or recreation, hunting, wildlife habitat, pine forests. Grasslands include yellow substrates. in the south/ intrusive rocks: pelitic schist, amphibole Argicryolls, Haplustolls) snowpack mountain meadows, and with Douglas-fi r at and seasonal grazing. Some gold Indiangrass, little bluestem, switchgrass, 400-2500 schist, quartzite, diamictite, quartz-pebble lower elevations. May include limber pine and mining. Snow cover is a major fescues, mountain muhly, Junegrass, bluebunch conglomerate, and marble. Precambrian Rocky Mountain bristlecone pine. Understory source of water for lower, more arid wheatgrass, needle-and-thread, slender granitic gneiss, felsic gneiss, amphibolite, is dominated by dwarf huckleberry and grouse ecoregions. wheatgrass, western wheatgrass, sideoats and granitic rocks. Copper, silver, and gold whortleberry. grama, and galleta grass. deposits. 21c. Crystalline 4455 Partially glaciated. Low mountain 7000-9000/ Quaternary glacial till, colluvium, and Alfi sols (Haplustalfs, Boyett, Granile, Larkson, Cryic, Frigid/ 20-32 60-90 8/36; Ponderosa pine forest with areas of Douglas- Evergreen and some deciduous 26j. Foothill 1805 Dissected and irregular plains. 5900-7000/ Quaternary alluvium. Tertiary and Cretaceous Mollisols (Argiustolls, Bresser, Truckton, Ellicott, Mesic/ 14-20 100-150 12/40; Foothills prairie with a scattering of pine Grassland, rangeland, some scattered ridges, slopes, and outwash fans. 400-1000 alluvium. Precambrian metasedimentary, Glossocryalfs), Peeler, Seitz, Wetmore, Udic, Ustic 50/80 fi r forest. Understory may include mountain forest. Wildlife habitat, rangeland, Grasslands 50-200 arkosic conglomerate, sandstone, claystone, Haplustolls), Entisols Stapleton, Columbine, Aridic, Ustic 52/84 woodlands. Yellow Indiangrass, big and little woodland and cropland. Increasing Mid-Elevation and shale. (Torrifl uvents), Aridisols Cushman, Ascalon bluestem, switchgrass, fescues, mountain urban and residential development. Forests Moderate to high gradient perennial metavolcanic, and intrusive rocks: pelitic Entisols (Cryorthents, Legault, Sphinx, Catamount, mahogany, bitterbrush, wax currant, timber production, recreation, and streams with boulder, cobble, and schist, amphibole schist, quartzite, diamictite, Ustorthents), Ivywild, Cabin, Frenchcreek, skunkbush, woods rose, mountain muhly, mineral extraction. Some gold (Haplargids) muhly, Junegrass, bluebunch wheatgrass, bedrock substrates. quartz-pebble conglomerate, and marble. Inceptisols Pendant, Pierian, Raleigh, Junegrass, Arizona fescue, king spike-fescue, mining. needle-and-thread, slender wheatgrass, western Precambrian granitic gneiss, felsic gneiss, (Dystrocryepts), Rogert, Teoculli, Woodhall and various sedges. wheatgrass, sideoats grama, and galleta grass. amphibolite, and granitic rocks. Copper, Mollisols (Argicryolls, Ponderosa pine, mountain mahogany, Gambel silver, and gold deposits. Haplocryolls) oak, western serviceberry, and chokecherry in small scattered pockets. 21d. Foothill 4780 Unglaciated. Hills, ridges, and Mostly Quaternary glacial till, colluvium, and Alfi sols (Haplustalfs), Ring, Bond, Bronell, Mesic, 12-20 75-100 10/36; Sagebrush shrubland, pinyon-juniper Shrubland and grassland, some 26k. Sand Sheets 566 Rolling plains with stabilized sand 3500-5900/ Quaternary eolian sands and alluvial gravels Entisols Valent, Vona, Bijou, Wigton Mesic/ 10-16 120-150 14/46; Sandsage prairie: sand sagebrush, sand Grassland, some shrubland, and Shrublands footslopes. Moderate to high gradient 6000-8500, alluvium. Tertiary and Cretaceous shale and Aridisols (Haplargids, Brownsto, Coaldale, Frigid, Cryic/ 46/84 woodland, and foothill-mountain grasslands. woodland. Rangeland and wildlife sheets and areas of low sand dunes. 25-100 and sands. Cretaceous shale and sandstone. (Torripsamments), Aridic, Ustic 60/88 bluestem, prairie sandreed, blowout grass, rangeland. perennial, intermittent, and ephemeral small sandstone. Permian sandstone, limestone, Haplocalcids), Potts, Kerhayden, Neville, Ustic, Aridic Also includes areas of mountain mahogany habitat. Aridisols (Haplargids), lemon scurfpea, and little bluestem. streams with cobble, gravel, and sandy areas up to and siltstone. Precambrian metasedimentary: Entisols (Torriorthents, Patent, Travessilla, Bowen, shrublands and scattered Gambel oak Alfi sols (Haplustalfs) substrates. 10000/ sandstone, claystone, shale, siltstone, and Ustorthents), Mollisols Bushvalley, Castner, woodlands. The woodlands are often 200-900 conglomerates. Precambrian metamorphic (Argicryolls, Argiustolls, Dominson, Embargo, Gelkie, interspersed with mountain big sagebrush, rocks: amphibolite, schist, gneiss, quartzite, Haplustolls, Calciustolls) Keeldar, Libeg, Lucky, skunkbush, serviceberry, fringed sage, quartz-pebble conglomerate, and marble. Martinsdale, Nederland, rabbitbrush, blue grama, Junegrass, western SOURCES: Noden, Norriston, Pando, wheatgrass, Indian ricegrass, Scribner Anderson, J.R., 1970, Major land uses, in The national atlas of the United States of America: Daubenmire, R.F., 1943, Vegetational zonation in the Rocky Mountains: The Botanical Review, Keane, R.E., Ryan, K.C., Veblen, T.T., Allen, C.D., Logan, J., and Hawkes, B., 2002, Cascading Schrupp, D.L., Reiners, W.A., Thompson, T.G., O’Brien, L.E., Kindler, J.A., Wunder, M.B., Parlin, San Isabel, St. Elmo needlegrass, muttongrass, and blue grama. 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Sedimentary 6196 Glaciated. High mountains with steep 8500-10000 Quaternary drift and colluvium. Faulted Alfi sols (Haplocryalfs, East: Ashcroft, Granile, Cryic/ 28-50 30-60 2/32; Subalpine forests dominated by subalpine Evergreen and some deciduous Rocky Mountain Forest and Range Experiment Station, General Technical Report RM 478, Kent, H.C., and Porter, K.W., 1980, Colorado geology: Denver, Colorado, Rocky Mountain Subalpine Forests slopes. High gradient perennial streams in the north, and folded Tertiary sedimentary rocks of Glossocryalfs), Entisols Leadville, Limber, Seitz, Udic, Ustic Deep 40/76 fi r, Engelmann spruce, and lodgepole pine. forest. Timber production, 14 p. Donnegan, J.A., Veblen, T.T., and Sibold, J.S., 2001, Climatic and human infl uences on fi re history Association of Geologists, 258 p. Sherriff, R.L., Veblen, T.T., and Sibold, J.S., 2001, Fire history in high elevation subalpine forests in in Pike National Forest, : Canadian Journal of Forest Research, v. 31, the Colorado Front Range: Ecoscience, v. 8, p. 369-380. with boulder, cobble, and bedrock 9000-12000 limestone, siltstone, shale, and sandstone. (Cryorthents), Inceptisols Vulcan, Wetterhorn, Gralic, winter Areas of Douglas-fi r or aspen forests at recreation, hunting, wildlife habitat, Allen, R.B., and Peet, R.K., 1990, Gradient analysis of forests of the Sangre de Cristo Range, p. 1526-1539. Komarkova,V., Alexander, R.R., Johnston, B.C., 1988, Forest vegetation of the Gunnison and parts substrates. in the south/ Permian arkosic conglomerate, sandstone, and (Eutrocryepts), Storm, Adel, Leaps, Ruby. snowpack lower elevations. Understory may include and seasonal grazing. Some gold Colorado: Canadian Journal of Botany, v. 68, p. 193-201. of the Uncompahgre National Forests - a preliminary habitat type classifi cation: Fort Collins, Stohlgren, T.J., Veblen, T.T., Kendall, K., Baker, W.L., Logan, A., and Ryan, M., 2002, The Heart 400-1500 siltstone of the Sangre de Cristo Formation. Mollisols (Haplocryolls, Southwest: Graysill, whortleberry, kinnickinnick, snowberry, mining. Snow cover is a major Dugan, J.T., 1986, Hydrologic characteristics of soils in parts of Arkansas, Colorado, Kansas, Colorado, U.S. Department of Agriculture - Forest Service, Rocky Mountain Forest and of the Rockies: Montane and subalpine ecosystems, in Baron, J., Fagre, D., and Hauer, R., Aplet, G.H., Laven, R.D., and Smith, F.W., 1988, Patterns of community dynamics in Colorado Missouri, Nebraska, New Mexico, Oklahoma, South Dakota, and Texas: Denver, Colorado, Range Experiment Station, 65 p. eds., Rocky Mountain futures - an ecological perspective: Washington, D.C., Island Press, Flat Tops Mountains: Pre-Pennsylvanian Argicryolls) Scotch, Needleton, Ryman. sedges, mountain brome, and forbs. source of water for lower, more arid Engelmann spruce-subalpine fi r forests: Ecology, v. 62, p. 312-319. U.S. Department of the Interior – Geological Survey, Hydrologic investigations atlas, HA- p. 203-219. Paleozoic limestone, sandstone, quartzite, and Uncompahgre Plateau: ecoregions. 678, scale 1:1,500,000. Kulakowski, D., and Veblen, T., 2002, Infl uences of fi re history and topography on the pattern of dolomite. Uncompahgre Plateau: Cretaceous Gateway Bailey, A.M., and Niedrach, R.J., 1965, Birds of Colorado: Denver, Colorado, Denver Museum of a severe wind blowdown in a Colorado subalpine forest: Journal of Ecology, v. 90, no. 5, Tuhy, J.S., Comer, P., Dorfman, D., Lammert, M., Humke, J., Cholvin, B., Bell, G., Neely, B., Natural History, 895 p. Erickson, K.A., and Smith, A.W., 1985, Atlas of Colorado Location: Boulder, Colorado, Colorado p. 806-819. Silbert, S., Whitham, L., and Baker, B., 2002, A conservation assessment of the Colorado sandstone and shale. Associated University Press, 73 p. Plateau ecoregion: Moab, Utah, The Nature Conservancy, 110 p. + appendices. Bailey, R.G., 1995, Description of the ecoregions of the United States (2nd ed.): Miscellaneous Loveland, T.R., Merchant, J.W., Brown, J.F., Ohlen, D.O., Reed, B.C., Olsen, P., and Hutchinson, J., Publication No. 1391, U.S. Department of Agriculture - Forest Service, 108 p. + map. Gallant, A.L., Whittier, T.R., Larsen, D.P., Omernik, J.M., and Hughes, R.M., 1989, Regionalization 1995, Seasonal land-cover regions of the United States: Annals of the Association of American Tweto, O., compiler, 1979, Geologic map of Colorado: Reston, Virginia, U.S. Geological Survey in as a tool for managing environmental resources: Corvallis, Oregon, U.S. Environmental Geographers, v. 85, no. 2, p. 339-355. cooperation with the Geological Survey of Colorado, scale 1:500,000. 21f. Sedimentary 7532 Partially glaciated. Low mountain 7000-9000/ Quaternary drift and colluvium. Faulted Alfi sols (Haplustalfs, East: Allens Park, Granile, Frigid, Cryic/ 20-32 60-90 6/34; Ponderosa pine forest, Gambel oak woodland, Evergreen and some deciduous Bailey, R.G., Avers, P.E., King, T., and McNab, W.H., eds., 1994, Ecoregions and subregions of the Protection Agency, EPA/600/3-89/060, 152 p. ridges, slopes, and outwash fans. 400-1000 and folded Tertiary sedimentary rocks of Glossocryalfs, Gulnare, Lakehelen, McIntyre, Udic, Ustic 44/84 and aspen forest (especially on the Western forest. Timber production, summer United States (map) (supplementary table of map unit descriptions compiled and edited by McGinnies, W.J., 1991, Changes in vegetation and land use in eastern Colorado - a photographic U.S. Department of Agriculture - Soil Conservation Service, 1981, Land resource regions and major Mid-Elevation Griffi ths, M., and Rubright, L., 1983, Colorado, a geography: Boulder, Colorado, Westview Press, Moderate to high gradient perennial limestone, siltstone, shale, and sandstone. Haplocryalfs), Mulgon, Seitz, Troutville, slope). Areas of mountain mahogany and two- livestock grazing, wildlife habitat, McNab, W.H., and Bailey, R.G.): Washington, D.C., U.S. Department of Agriculture - Forest study, 1904 to 1986: Springfi eld, Virginia, U.S Department of Agriculture - Agricultural land resource areas of the United States: Washington, D.C., U.S. Government Printing Offi ce, Forests Service, scale 1:7,500,000. 325 p. Research Service, 165 p. Agriculture Handbook 296, 156 p. + map. streams with boulder, cobble, and Uncompahgre Plateau: Cretaceous sandstone Entisols (Ustorthents), Ula, Wahatoya, Brownsto, needle pinyon pine. Shrub vegetation includes and recreation. Some copper, silver, bedrock substrates. and shale. Mollisols (Argicryolls, Patent, Cabin, Castner, antelope bitterbrush, fringed sage, serviceberry, and gold mining. Baker, W.L., 1984, A preliminary classifi cation of the natural vegetation of Colorado: Great Basin Hammerson, G.A., 1999, Amphibians and reptiles in Colorado: Niwot, Colorado, University Press Mitchell, J.E., 1993, The rangelands of Colorado: Rangelands, v. 15, no. 5, p. 213-219. U.S. Department of Agriculture - National Agricultural Statistics Service, 1999, Census of agriculture, Naturalist, v. 44, p. 647-676. of Colorado, 484 p. 1997, v. 2, subject series, part 1, agricultural atlas of the United States: Washington, D.C., U.S. Haplustolls, Argiustolls, Pierian, Poncha. Southwest: and snowberry. Understory grasses of Arizona Moir, W.H., 1969, The lodgepole pine zone in Colorado: The American Midland Naturalist, v. 81, Government Printing Offi ce, 163 p. Haplocryolls), Inceptisols Archuleta, Fivepine, Nortez, fescue, bluegrass, Junegrass, needlegrasses, Baker, W.L., 1992, Structure, disturbance, and change in the bristlecone pine forests of Colorado, Harper, K.T., St. Clair, L.L., Thorne, K.H., and Hess, W. M., 1994, Natural history of the Colorado no. 1, p. 87-98. U.S.A.: Arctic and Alpine Research, v. 1, p. 17-26. Plateau and Great Basin: Denver, Colorado, University Press of Colorado, 294 p. U.S. Department of Agriculture - Natural Resources Conservation Service, STATSGO soils data. (Haplustepts) Morapos, Cerro, Fughes, mountain muhly, pine dropseed, and mountain Mutel, C.F., and Emerick, J.C., 1992, From grassland to glacier - the natural : Nortez. Uncompahgre Plateau: brome. Baker, W.L., and Kennedy, S.C., 1985, Presettlement vegetation of part of northwestern Moffat Heil, R.D., Romine, D.S., Moreland, D.C., Dansdill, R.K., Montgomery, R.H., and Cipra, J.E., Boulder, Colorado, Johnson Publishing Company, 290 p. U.S. Geological Survey, 1986, Land use and land cover data from 1:250,000 and 1:100,000 scale County, Colorado, described from remnants: Great Basin Naturalist, v. 45, no. 4, p. 747-777. 1977, Soils of Colorado: Fort Collins, Colorado State University Experiment Station, in maps: Reston, Virginia, U.S. Geological Survey Data Users Guide no. 4. Mayfl ower, Cebone, Wetopa, cooperation with the U.S. Department of Agriculture - Soil Conservation Service, Bulletin Nadler, C.T., and Schumm, S.A., 1981, Metamorphosis of South Platte and Arkansas Rivers, Lamphier, Falcon Barnes, C.P., and Marschner, F.J., 1933, Natural land-use areas of the United States: U.S. Department 566S, 40 p. eastern Colorado: Physical Geography, v. 2, no. 2, p. 95-115. U.S. Department of Agriculture - Natural Resources Conservation Service (formerly Soil of Agriculture, scale 1:4,000,000. Conservation Service), various county soil surveys of Colorado. Hereford, R., Webb, R.H., and Graham, S., 2002, Precipitation history of the NatureServe, 2004, NatureServe Explorer: An online encyclopedia of life [Web application]. 21g. Volcanic 3940 Glaciated. High mountains with steep 9000- Quaternary drift and colluvium. Tertiary Alfi sols (Haplocryalfs, Frisco, Granile, Needleton, Cryic/ 28-50 30-60 2/32; Subalpine forests dominated by Engelmann Evergreen and some deciduous Bezner, A., and Kershaw, L., 1999, Rocky Mountain nature guide: Edmonton, Alberta, Lone Pine region, 1900-2000: Reston, Virginia, U.S. Department of the Interior – Geological Survey, Version 4.2. NatureServe, Arlington, Virginia. Available http://www.natureserve.org/explorer. U.S. Department of Agriculture - Soil Conservation Service, 1972, Natural vegetation - Subalpine Forests slopes. High gradient perennial streams 12000/ pyroclastic material, breccia, and volcanic ash Glossocryalfs), Seitz, Snowdon, Taglake, Udic, Ustic Deep 40/74 spruce, subalpine fi r, aspen and, in the north, forest. Timber production, Publishing, 191 p. USGS Fact Sheet, FS-02-119, 4 p. (Accessed: 2004). Colorado: Portland, Oregon, U.S. Department of Agriculture - Soil Conservation Service, with boulder, cobble, and bedrock 600-1800 fl ows, including basalt, andesitic lavas, and Inceptisols Clayburn, Hapgood, winter lodgepole pine. Understory may include recreation, hunting, wildlife habitat, scale 1:500,000. Branson, F.A., Miller, R.F., and McQueen, I.S., 1976, Moisture relationships in twelve northern Hess, K., and Alexander R.R., 1986, Forest vegetation of the Arapaho and Roosevelt National Neely, B., Comer, P., Moritz, C., Lammert, M., Rondeau, R., Pague, C., Bell, G., Copeland, H., substrates. water-laid volcanics and conglomerates. (Eutrocryepts), Lamphier, Wetopa. Rubble and snowpack whortleberry, kinnickinnick, snowberry, and seasonal grazing. Some gold desert shrub communities near Grand Junction, Colorado: Ecology, v. 57, p. 1104-1124. Forests in central Colorado - a habitat type classifi cation: Fort Collins, Colorado, U.S. Humke, J., Spackman, S., Schulz, T., Theobald, D., and Valutis, L., 2001, Southern Rocky Veblen, T.T., 2000, Disturbance patterns in southern Rocky Mountain forests, in Knight, R.L., Mollisols (Argicryolls, rock outcrops. sedges, mountain brome, and forbs. mining. Snow cover is a major Department of Agriculture - Forest Service, Rocky Mountain Forest and Range Experiment Mountains - an ecoregional assessment and conservation blueprint: Prepared by The Nature Smith, F., Buskirk, S.W., Romme, W.H., and Baker, W.L., eds., Forest fragmentation in the Brown, P.M., Kaufmann, M.R., and Shepperd, W.D., 1999, Long-term, landscape patterns of past Haplocryolls) source of water for lower, more arid Station, 48 p. Conservancy with support from the U.S. Forest Service, Rocky Mountain Region, Colorado : Boulder, Colorado, Colorado University Press, p. 31-54. fi re events in a montane ponderosa pine forest of central Colorado: Landscape Ecology, v. 14, Division of Wildlife, and Bureau of Land Management, 86 p. + appendices. ecoregions. p. 513-532. Hoffman, G.R., and Alexander, R.R., 1980, Forest vegetation of the Routt National Forest Veblen, T.T., and Lorenz, D.C., 1986, Anthropogenic disturbance and recovery patterns in montane in northwestern Colorado - a habitat type classifi cation: Fort Collins, Colorado, U.S. Noel, T.J., Mahoney, P.F., and Stevens, R.E., 1994, Historical atlas of Colorado: Norman, forests, Colorado Front Range: Physical Geography, v. 7, no. 1, p. 1-24. 21h. Volcanic Mid- 1010 Partially glaciated. Low mountain 7000-9000/ Quaternary drift and colluvium. Tertiary Alfi sols (Haplocryalfs, Frisco, Granile, Seitz, Shule, Cryic/ 20-32 60-90 4/32; Ponderosa pine, Douglas-fi r, and aspen forests, Evergreen and some deciduous Bryce, S.A., Omernik, J.M., Pater, D.E., Ulmer, M., Schaar, J., Freeouf, J., Johnson, R., Kuck, P., Department of Agriculture - Forest Service, Rocky Mountain Forest and Range Experiment Oklahoma, University of Oklahoma Press, 60 p. and Azevedo, S.H., 1998, Ecoregions of North Dakota and South Dakota (color poster with Station, Research Paper RM-221. Veblen, T.T., and Lorenz, D.C., 1990, The Colorado Front Range - a century of ecological change: Elevation Forests ridges, slopes, and outwash fans. 400-1000 pyroclastic material, breccia, and volcanic ash Glossocryalfs), Cochetopa, Youman Ustic 42/76 with scattered areas of Gambel oak woodlands. forest. Timber production, summer map, descriptive text, summary tables, and photographs): Reston, Virginia, U.S. Geological Peet, R.K., 1978, Latitudinal variation in southern Rocky Mountain forests: Journal of Salt Lake City, Utah, University of Utah Press, 186 p. Moderate to high gradient perennial fl ows, including basalt, andesitic lavas, and Mollisols (Argicryolls, Understory of dwarf juniper, western livestock grazing, wildlife habitat, Survey, scale 1:1,500,000. Hoffman, G.R., and Alexander R.R., 1983, Forest vegetation of the White River National Forest in Biogeography, v. 5, p. 275-289. streams with boulder, cobble, and water-laid volcanics and conglomerates. wheatgrass, Oregon grape, blue grama, sideoats and recreation. Some gold mining. western Colorado - a habitat type classifi cation: Fort Collins, Colorado, U.S. Department of Weber, W.A., 1987, Colorado fl ora - Western slope: Boulder, Colorado, Associated University Endoaquolls) Chapman, S.S., Bryce, S.A., Omernik, J.M., Despain, D.G., ZumBerge, J., and Conrad, M., 2004, Agriculture - Forest Service, Rocky Mountain Forest and Range Experiment Station, 36 p. Peet, R.K., 1988, Forests of the Rocky Mountains, in Barbour, M.G., and Billings, W.D., eds., Press, 530 p. bedrock substrates. grama, and needlegrasses. Ecoregions of Wyoming (color poster with map, descriptive text, summary tables, and North American terrestrial vegetation: Cambridge, Cambridge University Press, p. 63-101. photographs): Reston, Virginia, U.S. Geological Survey, scale 1:1,400,000. Howe, E., and Baker, W.L., 2003, Landscape heterogeneity and disturbance interactions in a Weber, W.A., and Wittmann, R.C., 2001, Colorado fl ora - Eastern slope: Boulder, Colorado, subalpine watershed in northern Colorado, USA: Annals of the Association of American Peet, R.K., 1991, Forest vegetation of the Colorado Front Range: Vegetatio, v. 45, p. 3-75. University Press of Colorado, 521 p. Chapman, S.S., Omernik, J.M., Freeouf, J.A., Huggins, D.G., McCauley, J.R., Freeman, C.C., Geographers, v. 93, no. 4, p. 797-813. 21i. Sagebrush Parks 2098 High intermontane valleys. Moderate 7500-9500/ Quaternary alluvium, colluvium, and loess. Mollisols (Argiustolls, Evanston, Gold Creek, Lucky, Cryic, Frigid/ 10-16 60-90 -4/28; Sagebrush shrubland: Wyoming big sagebrush, Shrubland and some grassland. Steinauer, G., Angelo, R.T., and Schlepp, R.L., 2001, Ecoregions of Nebraska and Kansas Rennicke, J., 1990, Colorado wildlife: Helena and Billings, Montana, Falcon Press, 138 p. West, N.E., 1988, Intermountain deserts, shrub steppes, and woodlands, in Barbour, M.G., gradient perennial streams with cobble, 100-400 Cretaceous and Tertiary sandstone, shale, Endoaquolls, Argicryolls, Parlin, Cheadle, Gas Creek Ustic, Aridic 44/78 mountain big sagebrush, black sagebrush, Recreation, rangeland, and wildlife (color poster with map, descriptive text, summary tables, and photographs): Reston, Virginia, Huber, T.P., 1993, Colorado - the place of nature, the nature of place: Niwot, Colorado, University and Billings, W.D., eds., North American terrestrial vegetation: Cambridge, Cambridge U.S. Geological Survey, scale 1:1,950,000. Press of Colorado, 296 p. Rogers, C.M., 1953, The vegetation of the Mesa de Maya region of Colorado, New Mexico and University Press, p. 209-230. gravel, and sandy substrates. siltstone, and conglomerate. Tertiary volcanic Haplocryolls) western wheatgrass, bottlebrush squirreltail, habitat. Some hay production. Oil Oklahoma: Lloydia, v. 16, no. 4, p. 257-290. rocks. and elk sedge. Areas of bunchgrasses include and gas production in North Park. Chronic, H., and Williams, F., 2002, Roadside geology of Colorado: Missoula, Montana, Mountain Huber, T.P., 1997, Colorado byways - a guide through scenic and historic landscapes: Niwot, Winward, A.H., 2004, Sagebrush of Colorado-taxonomy, distribution, ecology, and management: Arizona fescue and mountain muhly. Press Publishing Company, 399 p. Colorado, University Press of Colorado, 373 p. Rogers, C.M., 1954, Some botanical studies in the Black Mesa region of Oklahoma: Rhodora, v. Denver, Colorado, Colorado Division of Wildlife, 45 p. 56, no. 670, p. 205-212. Colorado Natural Areas Program, 1998, Native plant revegetation guide for Colorado: Denver, Huber, T.P., and Larkin, R.P., 1996, The of Colorado - a geographical sketch: Woods, A.H., Lammers, D.A., Bryce, S.A., Omernik, J.M., Denton, R.L., Domeier, M., Comstock, 21j. Grassland Parks 1254 High intermontane valleys. Moderate 7900-9800/ Quaternary alluvium, colluvium, and sand. Mollisols (Haplocryolls, Gebson, Alvarado, Becks, Cryic, Frigid/ 10-20 60-90 6/36; Foothill grasslands with bunchgrasses Grassland. Recreation, rangeland, Colorado, Natural Areas Program, Colorado State Parks, Colorado Department of Natural Colorado Springs, Colorado, The Hulbert Center for Southwestern Studies, The Colorado Rondeau, R., 2000, Ecological system viability specifi cations for Southern Rocky Mountain J.A., 2001, Ecoregions of Utah (color poster with map, descriptive text, summary tables, and gradient perennial streams with cobble, 100-400 Tertiary siltstone, sandstone, conglomerate, Argicryolls, Argiustolls, Bushvalley, Coutis, Feltonia, Ustic, some 40/76 dominant: Arizona fescue, Idaho fescue, and wildlife habitat. Resources, 272 p. College, 82 p. ecoregion: Fort Collins, Colorado, Colorado Natural Heritage Program, 181 p. photographs): Reston, Virginia, U.S. Geological Survey, scale 1:1,175,000. gravel, and sandy substrates. Some volcanic basalt and ash-fl ow tuff. Endoaquolls, Cryaquolls) Gas Creek, Gelkie, Hodden, Aquic Columbia needlegrass, Canby bluegrass, Comer, P., Menard, S., Tuffl y, M., Kindscher, K., Rondeau, R., Jones, G., Steinuaer, G., Schneider, Huber, T.P., and Wark, J., 2002, Colorado: an aerial geography of the highest state: Montrose, Ryan, M.G., Joyce, L.A., Andrews, T., and Jones, K., 1994, Research natural areas in Colorado, Wright, H.E., Jr., 1973, Vegetational history of the Central Plains, in Pleistocene and Recent wetlands. Precambrian gneiss, schist, and quartzite. Venable, Quander, Norriston, mountain muhly, bluebunch wheatgrass, R., and Ode, D., 2003, Upland and wetland ecological systems in Colorado, Wyoming, South Colorado, Western Refl ections Publishing, 148 p. Wyoming, Nebraska, North Dakota, South Dakota, and parts of Wyoming: Fort Collins, Environments of the Central Great Plains: University of Kansas Department of Geology, Dakota, Nebraska, and Kansas - Report and map to the National Gap Analysis Program, Colorado, U.S. Department of Agriculture - Forest Service, Rocky Mountain Forest and Special Publication 3, p. 157-172. Morset, Libeg, Hoodle needle-and-thread, Junegrass, and slender NatureServe, 29 p. plus appendices. Johnston, B.C., 1987, Plant associations of region two - potential plant communities of Wyoming, Range Experiment Station, General Technology Report RM 251, 57 p. wheatgrass. South Dakota, Nebraska, Colorado, and Kansas: Lakewood, Colorado, U.S. Department of Cottrell, T.R., and Bonham, C.D., 1992, Characteristics of sites occupied by subspecies of Agriculture - Forest Service, Rocky Mountain Region, 429 p. Artemisia tridentata in the Piceance Basin, Colorado: Great Basin Naturalist, v. 52, no. 2, p. 174-178.

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