LOCATION BROWNRIGG WYEstablished Series
TAXONOMIC CLASS: Loamy-skeletal, mixed, superactive, mesic, shallow Aridic Argiustolls
TYPICAL PEDON: Brownrigg very cobbly loam in a map unit of Brownrigg-Featherlegs-Wolf complex, 10 to 40 percent slopes, utilized as rangeland. (Colors are for dry soil unless otherwise stated.)
A--0 to 3 inches; dark grayish brown (10YR 4/2) very cobbly loam, very dark grayish brown (10YR 3/2) moist; moderate fine and very fine granular structure; slightly hard, very friable, slightly sticky, slightly plastic; 25 percent cobbles, 15 percent gravel and 5 percent stones; mildly alkaline (pH 7.8); clear smooth boundary. (2 to 5 inches thick)
Bt--3 to 8 inches; brown (10YR 4/3) very gravelly clay loam, dark brown (10YR 3/3) moist; strong fine and very fine subangular blocky structure; hard, firm, sticky, plastic; 35 percent gravel, 10 percent cobbles and 5 percent stones; common distinct clay films on faces of peds; mildly alkaline (pH 7.7) clear smooth boundary. (4 to 6 inches thick)
Bk--8 to 15 inches; brown (10YR 5/3) extremely gravelly loam, dark brown (10YR 4/3) moist; massive; slightly hard, friable, slightly sticky, slightly plastic; 45 percent gravel, 15 percent cobbles, and 5 percent stones; strongly effervescent; calcium carbonate disseminated and as thin pendants under rock fragments; moderately alkaline (pH 8.7); clear wavy boundary. (4 to 10 inches thick)
Cr--15 to 20 inches; calcareous sandstone.
TYPE LOCATION: Goshen County, Wyoming; 760 feet west and 1,090 feet north of the southeast corner of section 1, T27N, R65W. 42 degrees 20 minutes 17 seconds north latitude and 104 degrees 35 minutes 56 seconds west longitude.
RANGE IN CHARACTERISTICS: The mean annual soil temperature is 47 degrees to 54 degrees F. Depth to a paralithic contact is 10 to 20 inches. Depth to the base of the Bt horizon is 7 to 10 inches. Gravel, cobbles, and stones collectively in the profile range from 45 to 65 percent.
The A horizon has hue of 10YR or 7.5YR, value of 4 or 5 dry, 2 or 3 moist, and chroma of 2 or 3. It is fine sandy loam or loam modified by rock fragments. This horizon is mildly or moderately alkaline.
The Bt horizon has hue of 10YR or 7.5YR, value of 4 or 5 dry, 2 or 3 moist, and chroma of 2 or 3. It is loam, sandy clay loam, or clay loam averaging 18 to 35 percent clay, modified by rock fragments. This horizon is mildly or moderately alkaline.
The Bk or C horizon has hue of 10YR or 7.5YR. Texture is loam, sandy clay loam, or clay loam modified by rock fragments. It has a calcium carbonate equivalent of 4 to 15 percent.
COMPETING SERIES: There are no other series in this family.
GEOGRAPHIC SETTING: The Brownrigg soils are on gently undulating to steeply dissected pediments, hillslopes, mountain sides and alluvial fans. Slopes are 3 to 40 percent. The soils formed in colluvial outwash from mixed sedimentary, metamorphic, and igneous beds. Elevation is 4,800 to 5,800 feet. Annual precipitation is 13 to 15 inches. The average annual soil temperature is 47 to 52 degrees F. The frost-free season is 110 to 130 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Albinas, Featherlegs, Lambman, Rosebud, Satanta, Willowman and Wolf soils. Albinas soils are pachic. Featherlegs, Rosebud, Satanta, and Wolf soils are fine-loamy. Lambman soils are in the loamy family. Willowman and Wolf soils are very deep.
DRAINAGE AND PERMEABILITY: Well-drained; slow to rapid runoff; moderate permeability.
USE AND VEGETATION: These soils are used for rangeland and wildlife habitat. Native vegetation is blue grama, threadleaf sedge, little bluestem, prairie three-awn, western wheatgrass, needleandthread, scattered ponderosa pine and juniper.
DISTRIBUTION AND EXTENT: Southeastern Wyoming. The series is of small extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Denver, Colorado
Series Established: Goshen County (Northern Part), Wyoming, 1974.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
Mollic epipedon - 0 to 8 inches (A, Bt)
Argillic horizon - 3 to 8 inches (Bt)
SIR- WY0963
LRR=G