LOCATION DOMEPEAK COTentative Series
TAXONOMIC CLASS: Clayey-skeletal, smectitic Ustic Palecryalfs
TYPICAL PEDON: Domepeak very gravelly loam, on a north-facing, 25 percent slope in coniferous forest at an elevation of 9,920 feet. (Colors are for dry soil unless otherwise noted.) The surface is covered by about 2 percent sandstone stones.
Oi--0 to 1 inch; slightly decomposed plant material; clear smooth boundary. (1 to 3 inches thick)
E1--1 to 4 inches; pinkish gray (7.5YR 6/2) very gravelly loam; dark brown (7.5YR 3/2) moist; weak fine granular structure; soft, very friable, slightly sticky and slightly plastic; many very fine and medium roots, common very fine and coarse roots; 25 percent gravel, 10 percent cobbles; neutral (pH 6.6); clear wavy boundary.
E2--4 to 17 inches; light brown (7.5YR 6/3) very cobbly loam, brown (7.5YR 4/3) moist; weak medium subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; many medium and coarse roots, common very fine and fine roots; few very fine tubular pores; 30 percent gravel, 25 percent cobbles, 3 percent stones; slightly acid (pH 6.4); gradual wavy boundary. (The combined thickness of the E horizon is 12 to 35 inches)
E/Bt--17 to 26 inches; 80 percent pinkish gray (7.5YR 7/2) very cobbly loam (E), brown (7.5YR 4/3) moist; weak medium subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; common fine roots; few very fine tubular pores; 25 percent gravel, 20 percent cobbles, 5 percent stones; slightly acid; 20 percent light brown (7.5YR 6/3) very cobbly sandy clay loam (Bt), light brown (7.5YR 6/3) moist; weak medium subangular blocky structure; hard, firm, slightly sticky and slightly plastic; common fine roots; few very fine tubular pores; common distinct clay films on faces of peds; many continuous distinct skeletans on faces of peds; 25 percent gravel, 20 percent cobbles, 5 percent stones; slightly acid (pH 6.3); gradual wavy boundary. (0 to 10 inches thick)
Bt/E--26 to 40 inches; 80 percent light brown (7.5YR 6/3) very cobbly clay (Bt), light brown (7.5YR 6/3) moist; moderate medium subangular blocky structure; very hard, very firm, very sticky and very plastic; few very fine and fine roots; common very fine tubular pores; many prominent clay films on faces of peds; many continuous distinct skeletans on faces of peds; 20 percent gravel, 20 percent cobbles, 5 percent stones; slightly acid; 20 percent pinkish gray (7.5YR 7/2) very cobbly loam (E), brown (7.5YR 4/3) moist; weak medium subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; common fine roots; few very fine tubular pores; 20 percent gravel, 20 percent cobbles, 5 percent stones; slightly acid (pH 6.3); gradual wavy boundary. (7 to 15 inches thick)
Bt--40 to 60 inches; brown (7.5YR 5/3) very stony clay, brown (10YR 5/3) moist; moderate medium and coarse prismatic structure parting to strong medium and coarse subangular blocky; very hard, very firm, very sticky and very plastic; many prominent clay films on faces of peds; 15 percent gravel, 15 percent cobbles, 10 percent stones; slightly acid (pH 6.2). (15 to 30 inches thick)
TYPE LOCATION: Routt County, Colorado; about 5 miles southwest of Toponas; about 1,900 feet west and 400 feet north of the southeast corner of sec. 31, T. 1 N., R. 85 W.; Trapper USGS quad; lat. 40 degrees 00 minutes 12 seconds N. and long. 106 degrees 51 minutes 09 seconds W., NAD 27.
RANGE IN CHARACTERISTICS: (Depths given are measured from the mineral soil surface)
Soil moisture: The soil moisture regime is udic bordering ustic.
Mean annual soil temperature: 38 to 42 degrees F
Mean annual summer soil temperature: 52 to 58 degrees F
Depth to glossic horizon: 12 to 35 inches
Depth to argillic horizon: 24 to 35 inches
Depth to Bt horizon: 45 to 48 inches
Thickness of the argillic horizon: 13 to 30 inches
Surface fragments: 1 to 3 percent stones
Lithology of rock fragments: sandstone
Particle-size control section (weighted average):
Clay content: 35 to 45 percent
Rock fragment content: 40 to 70 percent
Oi horizon:
Texture: slightly decomposed plant material
Reaction: pH 5.1 to 6.0
E horizons:
Hue: 7.5YR or 10YR
Value: 6 or 7 dry, 4 to 6 moist
Chroma: 1 to 4, dry or moist
Texture: very gravelly loam, very cobbly sandy loam, very cobbly loam
Clay content: 10 to 20 percent
Fragment content: 10 to 30 percent gravel, 10 to 30 percent cobbles, 0 to 5 percent stones
Reaction: slightly acid to neutral (pH 6.1 to 7.3)
E/Bt and Bt/E horizons (the E/Bt is not in all pedons):
E part:
Hue: 7.5YR or 10YR
Value: 6 or 7 dry; 4 to 6 moist
Chroma: 2 to 4 dry or moist
Texture: very gravelly loam, very cobbly loam, very cobbly sandy loam, very gravelly clay loam, very cobbly clay loam, very cobbly sandy clay loam
Clay content: 10 to 30 percent
Fragment content: 10 to 30 percent gravel, 10 to 30 percent cobbles, 0 to 5 percent stones
Bt part:
Hue: 7.5YR or 10YR
Value: 5 or 6, dry or moist
Chroma: 3 to 5, dry or moist
Texture: very gravelly sandy clay loam, very cobbly sandy clay loam, very cobbly clay loam, very cobbly clay
Clay content: 30 to 45 percent
Fragment content: 10 to 30 percent gravel, 10 to 30 percent cobbles, 0 to 5 percent stones
Bt horizon:
Hue: 7.5YR or 10YR
Value: 5 to 7 dry, 4 to 6 moist
Chroma: 3 to 6, dry or moist
Texture: very stony clay, very cobbly clay, very cobbly clay loam, very stony clay loam
Clay content: 35 to 45 percent
Fragment content: 10 to 20 percent gravel, 15 to 35 percent cobbles, 1 to 10 percent stones
COMPETING SERIES: This is the Mortenson series. Mortenson soils have mean annual soil temperature warmer than 42 degrees.
GEOGRAPHIC SETTING:
Parent material: slope alluvium and colluvium derived from sandstone and shale
Landform: mountains, hills
Slopes: 15 to 50 percent
Elevation: 8,200 to 10,200 feet
Mean annual air temperature: 37 to 41 degrees F
Mean annual precipitation: 18 to 25 inches
Precipitation pattern: precipitation is relatively evenly distributed throughout the year
Frost-free period: 50 to 80 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Dorpat, Fulvance, and Reddles series. The Dorpat and Reddles soils have less than 35 percent rock fragments. Dorpat is generally found on less steep slopes. The Fulvance soils have less than 35 percent clay. Fulvance and Reddles soils are located on the same landforms and slopes as Domepeak.
DRAINAGE AND PERMEABILITY: well drained, high runoff, slow permeability.
USE AND VEGETATION: The major uses are timber production, recreation, and wildlife habitat. Native vegetation is Rocky Mountain Douglas fir, lodgepole pine, subalpine fir, aspen, heartleaf arnica, snowberry, timothy, and elk sedge.
DISTRIBUTION AND EXTENT: Northwest Colorado; LRR E, MLRA 48A; small extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Bozeman, Montana
SERIES PROPOSED: Routt County, Colorado, Routt Area soil survey area, 2004. The name Domepeak is taken from a local mountain peak.
REMARKS:
Diagnostic horizons and features recognized in this pedon are:
Ochric epipedon: The zone from 1 to 4 inches. (E1 horizon).
Argillic horizon: The zone from 26 to 60 inches. (Bt/E and Bt horizons).
Glossic horizon: The zone from 17 to 40 inches. (E/Bt and Bt/E horizons).
Particle-size control section: The zone from 26 to 46 inches (Bt/E, and part of Bt horizon).
Series control section: from the soil surface to the base of the argillic horizon (0 to greater than 60 inches).
Taxonomic Version: classified according to the 10th edition, 2006.