LOCATION BUCKSKIN                ID

Established Series
Rev. WJL-RJE-RJS
06/2011

BUCKSKIN SERIES

The Buckskin series consists of very deep, well drained soils that formed in loess. These soils are on hills. Slopes are 5 and 20 percent. Mean annual precipitation is about 18 inches.

TAXONOMIC CLASS: Fine, smectitic Vertic Argicryolls

TYPICAL PEDON: Buckskin silt loam, in 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 structure, parting to moderate fine and medium granular; slightly hard, friable, slightly sticky and slightly plastic; 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 structure, parting to weak fine granular; hard, firm, slightly sticky and slightly plastic; 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, brown (7.5YR 4/3) moist; moderate medium prismatic structure, parting to strong fine and medium subangular blocky; extremely hard, very firm, very sticky and very plastic; 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 4/2) moist; moderate medium prismatic structure, parting to strong very fine and fine subangular blocky; very hard, very firm, moderately sticky and moderately plastic; 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 structure, parting to moderate very fine and fine subangular blocky; hard, firm, moderately sticky and moderately plastic; few very fine roots; many very fine and fine tubular pores; thin patchy clay films on peds and in pores; 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:
Moisture regime: xeric
Mean annual soil temperature - 36 to 44 degrees F.
Mean summer soil temperature at a depth of 20 inches - from 55 to 59 degrees F.
Thickness of mollic epipedon - 10 to 16 inches
Depth to calcareous material - 5 feet or deeper
Thickness of solum - 40 to 65 inches
Reaction class: 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

Note: Na plus K saturation does not increase within 35 inches of the surface

Bt1, Bt2 horizons
Hue: 7.5YR or 10YR; dry or moist
Value: 5 or 6 dry; 3 or 4 moist
Chroma: 2 or 3; dry or moist
Texture: light silty clay to silty clay loam
Clay content: 35 to 45 percent
Structure: weak to moderate medium to coarse prismatic and moderate to strong very fine to medium subangular blocky
Silt coatings: few to common on peds

COMPETING SERIES:
Beaverdam (ID) - have an udic moisture regime
Chicken (MT) - are moderately deep to a paralithic contact
Cimarron (CO) - have an ustic moisture regime
Cooperwash (NV) - have secondary calcium carbonate accumulation
Cucharas (CO) - are moderately deep to a paralithic contact
Gourley (CO) - have secondary calcium carbonate accumulation
Hairpin (MT) - have an ustic moisture regime
Heathcoat (ID) - have secondary calcium carbonate accumulation
Helmet (CO) - have an udic moisture regime
Savar (WY) - have an ustic moisture regime
Slights (ID) - have a mollic epipedon greater than 16 inches
Sudduth (CO) - have an udic moisture regime
Sudpeak (ID) - have a mollic epipedon greater than 16 inches
Toponce (ID) - have a mollic epipedon greater than 16 inches
Wetopa (CO) - have an udic moisture regime
Youman (CO) - have an ustic moisture regime

GEOGRAPHIC SETTING:
Landform - hills (particularly in concave or cove like positions)
Elevation - 5,500 to 7,000 feet; the lower elevations are on more northerly aspects
Slope - 5 and 20 percent
Parent material - loess
Climate - continental, subhumid
Mean annual precipitation - 17 to 25 inches; 5 to 9 feet of snowfall
Mean annual air temperature - not listed
Frost-free period - 50 to 100 days

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 mainly Nevada bluegrass, bluebunch wheatgrass, big sagebrush, forbs, and in places aspen.

DISTRIBUTION AND EXTENT: High loessal uplands of southeastern Idaho. The series is of moderate extent. MLRAs - 13, 43B.

MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Bozeman, Montana.

SERIES ESTABLISHED: Star Valley Area, Idaho and Wyoming, 1971.

REMARKS: Diagnostic horizons and features recognized in this pedon are:
Mollic epipedon - from 0 to 12 inches (A1, A2 horizons)
Argillic horizon - from 12 to 61 inches (Bt1, Bt2, Bt3 horizons)
Particle-size control section - from 12 to 32 inches (Bt1, part of Bt2 horizons)

Buckskin soils have a cryic temperature regime and a xeric moisture regime.

Additional Information: The soil moisture regime has been defined as xeric because the type location in Idaho is xeric (6/10/2011).

---

National Cooperative Soil Survey
U.S.A.