LOCATION JENKINSON WYEstablished Series
TAXONOMIC CLASS: Loamy, mixed, superactive Lithic Haplocryolls
TYPICAL PEDON: Jenkinson channery clay loam-rangeland. (Colors are for dry soil unless otherwise stated.)
A--0 to 8 inches; grayish brown (2.5Y 5/2) channery clay loam, very dark grayish brown (2.5Y 3/2) moist; moderate very fine granular structure; soft, very friable, moderately sticky; 25 percent small flat rock fragments; calcareous; moderately alkaline (pH 8.2); clear smooth boundary. (6 to 12 inches thick)
C--8 to 14 inches; light yellowish brown (2.5Y 6/3) channery clay loam, olive brown (2.5Y 4/3) moist; very weak medium subangular blocky structure; slightly hard; very friable, moderately sticky; 25 percent small flat rock fragments; calcareous; moderately alkaline (pH 8.3); gradual wavy boundary. (4 to 8 inches thick)
R--14 inches; interbedded hard sandstone and slate-like phyllitic shale.
TYPE LOCATION: Johnson County, Wyoming; NW1/4, NW1/4, sec. 27, T. 45 N., R. 85 W.
RANGE IN CHARACTERISTICS: The mollic epipedon is 7 to 12 inches thick. Depth to bedrock is 10 to 20 inches. The mean annual soil temperature is about 38 to 45 degrees F. The control section is channery loam or channery clay loam. Clay averages 18 to 35 percent. Small slate-like fragments range from 15 to 35 percent. The soil is calcareous throughout.
The A horizon has hue of 5Y through 10YR, value of 4 or 5 dry, 2 or 3 moist, and chroma of 2 or 3. It is channery loam or channery clay loam. This horizon is moderately or strongly alkaline.
The C horizon has hue of 5Y through 10YR, value of 5 through 7 dry, 4 through 6 moist, and chroma of 2 or 3. It is channery loam or channery clay loam. This horizon is moderately or strongly alkaline.
COMPETING SERIES: These are the Dickle, Hazton, Heisspitz, Lotex, Mucet, Paddy, Skisams, Spliten, Splitro, Taylow, Trump, Tuggle, and Udelope series. Hazton soils are noncalcareous, have less than 18 percent clay in the control section, contain a high proportion of medium and coarse angular granite sand and gravel. Heisspitz soils are not calcareous and have a udic moisture regime. Lotex soils are not calcareous and are 8 to18 percent clay. Paddy, Skisams, Tuggle, and Udelope soils are not calcareous. Splitro soils are noncalcareous and have less than 18 percent clay in the control section. Dickle, Spliten, and Taylow soils are not calcareous and have a xeric moisture regime. Mucet soils formed in material weathered from basalt. Trump soils have continuous horizons of secondary carbonate accumulation and have cambic horizons.
GEOGRAPHIC SETTING: These soils are on mountainsides and mountain crests. Slopes are 2 to 30 percent. The soils formed in parent material weathered from underlying interbedded sandstone and phyllitic shale. At the type location the average annual precipitation is about 18 to 24 inches. The average annual temperature is 36 to 42 degrees F. Elevations are 7,000 to 9,000 feet. The frost-free season is 60 to 90 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Turk soils and the competing Duncom soils. Turk soils have an argillic horizon and are very fine textured.
DRAINAGE AND PERMEABILITY: Well drained; medium to rapid runoff; moderate permeability.
USE AND VEGETATION: Used for range, recreation, and wildlife habitat. Native vegetation is Idaho fescue, green needlegrass, cactus, and yarrow.
DISTRIBUTION AND EXTENT: Big Horn Mountains of north central Wyoming. This series is of moderate extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Bozeman, Montana
SERIES ESTABLISHED: Johnson County (Southern Part), Wyoming; 1971.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
Mollic epipedon from the soil surface to 8 inches (A horizon);
Lithic contact at 14 inches (the contact at the top of the R horizon);
A particle-size control section from the soil surface to 14 inches.
Jenkinson soils have a cryic temperature regime and an ustic moisture regime.