LOCATION BILHIL COEstablished Series
TAXONOMIC CLASS: Fine, smectitic, frigid Torrertic Haplustolls
TYPICAL PEDON: Bilhil clay loam-cropland. (Colors are for dry soil unless otherwise noted.)
A--0 to 3 inches; grayish brown (10YR 5/2) clay loam, very dark grayish brown (10YR 3/2) moist; moderate fine granular structure; slightly hard, friable, very sticky and very plastic; neutral (pH 7.0); clear smooth boundary. (3 to 10 inches thick)
AB--3 to 12 inches; brown (10YR 5/3) clay loam, dark brown (10YR 3/3) moist; moderate medium subangular blocky structure parting to moderate fine subangular blocky; very hard, friable, very sticky and very plastic; neutral (pH 7.0); clear smooth boundary. (0 to 10 inches thick)
Bw--12 to 23 inches; yellowish brown (10YR 5/4) clay, dark yellowish brown (10YR 4/4) moist; moderate coarse angular blocky structure; very hard, firm, very sticky and very plastic; mildly alkaline (pH 7.4); abrupt wavy boundary. (10 to 20 inches thick)
Bk1--23 to 36 inches; light yellowish brown (10YR 6/4) clay, yellowish brown (10YR 5/4) moist; moderate coarse prismatic structure parting to moderate coarse angular blocky; hard, firm, very sticky and very plastic; common fine threads of calcium carbonate; strongly effervescent; moderately alkaline (pH 8.4); clear wavy boundary. (8 to 15 inches thick)
Bk2--36 to 46 inches; light yellowish brown (10YR 6/4) clay, yellowish brown (10YR 5/4) moist; moderate coarse angular blocky structure; hard, firm, very sticky and very plastic; few fine threads of calcium carbonate; slightly effervescent; moderately alkaline (pH 8.2); gradual wavy boundary. (7 to 12 inches thick)
Bk3--46 to 54 inches; light yellowish brown (10YR 6/4) clay, yellowish brown (10YR 5/4) moist; few fine faint yellowish brown (10YR 5/8) mottles; moderate coarse angular blocky structure; hard, firm, very sticky and very plastic; few fine threads of calcium carbonate; slightly effervescent; moderately alkaline (pH 8.2); clear wavy boundary. (7 to 11 inches thick)
Bk4--54 to 60 inches; pale brown (10YR 6/3) clay, brown (10YR 5/3) moist; common medium distinct strong brown (7.5YR 5/8) and gray (2.5Y 6/1) mottles; moderate coarse angular blocky structure; hard, firm, very sticky and very plastic; few fine threads of calcium carbonate; slightly effervescent; moderately alkaline (pH 8.4).
TYPE LOCATION: Moffat County, Colorado; about 1 mile south of Craig; about 1,200 feet east and 200 feet south of the northwest corner of Sec. 1, T.6 N., R 91 W. Latitude: 40 degrees, 30 minutes, 48 seconds north; longitude: 107 degrees, 33 minutes, 29 seconds west.
RANGE IN CHARACTERISTICS: The mean annual soil temperature ranges from 44 to 46 degrees F., and the mean summer soil temperature ranges from 62 to 64 degrees F. Depth to effervescent horizons ranges from 0 to 25 inches. Depth to secondary calcium carbonate ranges from 15 to 25 inches. The mollic epipedon is 7 to 13 inches thick.
The A horizons have a value of 4 or 5 dry, 2 or 3 moist, and a chroma of 2 or 3. Reaction is neutral or mildly alkaline.
The Bw horizon has a hue of 10YR or 2.5Y, value of 5 or 6 dry, 4 or 5 moist, and a chroma of 3 or 4. Texture is clay, clay loam, or silty clay loam. Reaction is mildly alkaline or moderately alkaline.
The Bk horizons have a hue of 10YR or 2.5Y, value of 6 or 7 dry, 5 or 6 moist, and chroma of 3 or 4. Texture is clay, clay loam, or silty clay loam.
COMPETING SERIES: This is the Richey (MT)(T) series. The Richey series is well drained and contains horizons with an accumulation of gypsum and other soluble salts above a depth of 30 inches.
GEOGRAPHIC SETTING: Bilhil soils are on terraces and fans. The soils formed in alluvium derived from various sources. Slopes range from 0 to 3 percent. Elevation is 6,000 to 6,800 feet. Mean annual precipitation ranges from 12 to 15 inches; the mean annual temperature ranges from 42 to 45 degrees F., and the frost-free period is 75 to 95 days. July is the driest month during the growing season at the type location.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Apmay, Bulkley, and Lander soils. The Apmay soil is somewhat poorly drained and is in a fine-loamy over sandy or sandy-skeletal family. The Bulkley soil lacks a mollic epipedon and is well drained. The Lander soil is somewhat poorly drained and is in a fine-loamy family.
DRAINAGE AND PERMEABILITY: Moderately well drained; slow runoff; very slow permeability. A seasonal high water table fluctuates between a depth of 36 and 60 inches in April through June.
USE AND VEGETATION: These soils are used for irrigated hay, livestock grazing and urban development. Native vegetation consists of basin wildrye, western wheatgrass, slender wheatgrass, Nevada bluegrass and basin big sagebrush.
DISTRIBUTION AND EXTENT: These soils occur in northwestern Colorado. The series is of small extent. Total acreage is about 1,800 acres.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Bozeman, Montana
SERIES ESTABLISHED: Moffat County (Moffat County Area), Colorado, 1991.
REMARKS: The diagnostic horizons recognized in this pedon are the mollic epipedon - the zone from 0 to 12 inches, and the cambic horizon - the zone from 12 to 23 inches. Moisture regime is bordering on Ustic or is Aridic Ustic. Last updated by the state 12/90.