LOCATION BUCKSKIN ID+WYEstablished Series
TAXONOMIC CLASS: Fine, smectitic Vertic Argicryolls
TYPICAL PEDON: Buckskin silt loam - brush and grass. (Colors are for the dry soil unless otherwise noted.)
A1--0 to 4 inches; dark grayish brown (10YR 4/2) silt loam, very dark brown (10YR 2/2) moist; weak very thin and thin platy, parting to moderate fine and medium granular structure; slightly hard, friable, slightly plastic, slightly sticky; many very fine, fine, and medium roots; many very fine pores; very few uncoated silt particles; neutral (pH 6.8); clear smooth boundary. (4 to 10 inches thick)
A2--4 to 12 inches; dark grayish brown (10YR 4/2) silt loam, very dark brown (10YR 2/2) moist; weak very fine subangular blocky, parting to weak fine granular structure; hard, firm, slightly plastic, slightly sticky; many very fine, fine, and medium roots; common very fine tubular pores and very few insect channels 0.5 inch across; few uncoated silt particles; neutral (pH 7.0); clear smooth boundary. (4 to 10 inches thick)
Bt1--12 to 23 inches; brown (10YR 5/3) silty clay, dark brown (7.5YR 3/3) (7.5YR 4/3 crushed) moist; moderate medium prismatic, parting to strong fine and medium subangular blocky structure; extremely hard, very firm, very plastic, very sticky; few very fine, fine, and medium roots; many very fine and fine tubular pores; few 0.5 inch insect krotovinas; medium, nearly continuous clay films on peds and in pores; common uncoated silt particles on peds; neutral (pH 6.9); clear smooth boundary. (8 to 15 inches thick)
Bt2--23 to 35 inches; brown (7.5YR 5/3) silty clay loam, brown (7.5YR 4/3) (7.5YR 4/2 crushed) moist; moderate medium prismatic, parting to strong very fine and fine subangular blocky structure; very hard, very firm, moderately plastic, moderately sticky; few very fine, fine, and medium roots; many very fine and fine tubular pores; thin patchy clay films on peds and in pores; very few uncoated silt particles on peds; neutral (pH 6.8); clear wavy boundary. (10 to 22 inches thick)
Bt3--35 to 61 inches; brown (7.5YR 5/3) light silty clay loam, dark brown (7.5YR 3/2) moist; weak coarse prismatic, parting to moderate very fine and fine subangular blocky structure; hard, firm, moderately plastic, moderately sticky; few very fine roots; many very fine and fine tubular pores; thin patchy clay films on peds and in pores; noncalcareous; neutral (pH 7.1); clear wavy boundary. (5 to 30 inches thick)
C--61 to 70 inches; pale brown (10YR 6/3) silt loam; massive; friable; moderately calcareous.
TYPE LOCATION: Bannock County, Idaho; 95 feet northeast of large rock; at elevation 6,300 feet, 10 percent southwesterly slope; 500 feet south of the north quarter corner of sec. 10, T.6S., R.36E.
RANGE IN CHARACTERISTICS: The mean annual soil temperature ranges from 36 degrees to 44 degrees F., and the mean summer temperature at a depth of 20 inches ranges from 55 degrees to 59 degrees F. The soils are noncalcareous to 5 feet or deeper. They are slightly acid to slightly alkaline (pH 6.1 to 7.4) in the upper part and the reaction remains constant or becomes slightly more alkaline with depth. Na plus K saturation does not increase within 35 inches of the surface. No bedrock or contrasting texture is above 40 inches. The solum is 40 to 65 inches thick. The mollic epipedon is 10 to 16 inches thick. The upper 20 inches of the argillic horizon ranges from light silty clay to silty clay loam and has 35 to 45 percent clay, and thin patchy to medium continuous clay films. The B2t horizon has hue of 7.5YR or 10YR, value of 5 or 6 dry and 3 or 4 moist and chroma of 2 or 3. It has weak to moderate medium to coarse prismatic and moderate to strong very fine to medium subangular blocky structure. It has few to common coated silt specking on the peds.
COMPETING SERIES: These are Beaverdam, Cimarron, Cucharas, Gourley, Heathcoat, Slights, Sudduth, Toponce, Wetopa, and Youman series.
GEOGRAPHIC SETTING: These soils are on undulating to hilly uplands, particularly in concave or covelike positions. Elevations are 5,500 to 7,000 feet. Slopes are dominantly between 5 and 20 percent. At the lower elevations the slopes are northerly. These soils formed principally in loess. The continental subhumid climate has an average freeze-free period of 50 to 100 days and a mean annual precipitation of 17 to 25 inches, including 5 to 9 feet of snowfall.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Lanark and Robana soils. Lanark and Robana soils have a fine-silty control section. Also, Robana soils have a mollic epipedon more than 16 inches thick.
DRAINAGE AND PERMEABILITY: Well-drained; medium runoff; slow permeability in the B2t horizon.
USE AND VEGETATION: Used mostly for nonirrigated small grains, hay, and range. The natural vegetation is chiefly Nevada bluegrass, bluebunch wheatgrass, big sagebrush, forbs, and in places aspen.
DISTRIBUTION AND EXTENT: High loessal uplands of southeastern Idaho and western Wyoming. The series is of moderate extent.
MLRA OFFICE RESPONSIBLE: Bozeman, Montana
SERIES ESTABLISHED: Star Valley Area, Idaho and Wyoming, 1971.