LOCATION SHIRTTAIL SDEstablished Series
TAXONOMIC CLASS: Loamy-skeletal over sandy or sandy-skeletal, mixed, superactive, frigid Typic Argiustolls
TYPICAL PEDON: Shirttail channery loam - on a south-facing slope of 40 percent under native grass and scattered pine trees at an elevation of 4700 feet. When described, the soil was dry throughout. (Colors are for dry soil unless otherwise noted.)
A--0 to 6 inches; dark grayish brown (10YR 4/2) channery loam, very dark grayish brown (10YR 3/2) moist; weak fine granular structure; soft, friable; 20 percent by volume of fragments of rock; moderately acid; clear smooth boundary. (6 to 8 inches thick)
Bt1--6 to 11 inches; strong brown (7.5YR 5/6) very channery clay loam, dark brown (7.5YR 4/4) moist; moderate medium prismatic structure parting to moderate medium subangular blocky; hard, firm; 35 percent by volume of fragments of rock; slightly acid; gradual wavy boundary.
Bt2--11 to 18 inches; yellowish brown (10YR 5/4) very channery clay loam, dark yellowish brown (10YR 4/4) moist; weak medium subangular blocky structure; hard, friable; 45 percent by volume of fragments of rock; slightly acid; gradual wavy boundary. (Combined Bt horizons is 8 to 12 inches thick.)
BC--18 to 24 inches; yellowish brown (10YR 5/6) very channery loam, dark yellowish brown (10YR 4/6) moist; very weak fine and medium subangular blocky structure; soft, very friable; 40 percent by volume of fragments of rock; neutral; gradual wavy boundary. (0 to 20 inches thick)
C--24 to 44 inches; yellowish brown (10YR 5/4) very channery loamy fine sand, dark yellowish brown (10YR 4/4) moist; single grain; loose; 40 percent by volume of fragments of rock; neutral; abrupt wavy boundary.
R--44 to 60 inches; consolidated metamorphic rock.
TYPE LOCATION: Custer County, South Dakota; about 3 miles east and 1 mile north of Pringle; 1400 feet east and 1900 feet south of northwest corner, sec. 16, T. 5 S., R. 5 E.
RANGE IN CHARACTERISTICS: The thickness of the mollic epipedon ranges from 6 to 10 inches. The soil typically does not have carbonates throughout the profile, but some pedons have carbonates below depths of 40 inches. Fragments of rock are dominantly cobbles, channers, and flagstones and range from 15 to 30 percent by volume in the surface layer and from 35 to 70 percent by volume in the control section. Depth to consolidated bedrock is at depths of 40 to 60 inches.
The A horizon has hue of 7.5YR or 10YR, value of 4 to 6 and 2 or 3 moist, and chroma of 1 or 2. It is loam, or sandy loam. It ranges from moderately acid to slightly acid.
The Bt horizon has hue of 5YR to 10YR, value of 5 or 6 and 4 or 5 moist, and chroma of 3 to 6. Clay content ranges from 27 to 35 percent. It ranges from moderately acid to slightly acid.
The BC horizon has hue of 5YR to 10YR, value of 5 to 6 and 4 to 5 moist, and chroma of 3 to 6. It is loam or fine sandy loam and contains 35 to 70 percent by volume of fragments of rock. It ranges from moderately acid to neutral.
The C horizon has value of 5 to 7 and 4 to 6 moist and chroma of 4 to 6. It is loam, fine sandy loam, and loamy fine sand and contains 35 to 70 percent by volume of fragments of rock. It is strongly acid to neutral.
COMPETING SERIES: These are the Beaverton, Curecanti, Harol, Harpole, Hilger, Shawmut, and Widtsoe in the same family. Beaverton, Hilger, Shawmut, and the Widtsoe soils have a horizon of carbonate accumulation at the base of the argillic horizon. Curecanti soils are more than 20 inches deep to the base of the argillic horizon, do not have bedrock at depths above 60 inches and formed in alluvium and glacial outwash. Harol soils have thicker mollic epipedons and less clay and more sand in the C horizon. Harpole soils contain less clay in the argillic horizon and typically are more alkaline.
GEOGRAPHIC SETTING: Shirttail soils are gently sloping to very steep on uplands in mountains at elevations of 3600 to 6200 feet. Slope gradient ranges from 2 to 60 percent. These soils formed in residuum of metamorphic and granitic rocks. Mean annual temperature ranges from 37 to 45 degrees F. Mean annual precipitation ranges from 18 to 26 inches.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Buska, Cordeston, Mocmont, and Pactola soils. The Buska, Mocmont, and Pactola soils are on adjacent side slopes which are forested. The Buska soils have micaceous mineralogy. The Mocmont and Pactola soils do not have a mollic epipedon. The Cordeston soils do not have the coarse fragments and occur in the open parks.
DRAINAGE AND PERMEABILITY: Well drained. Permeability is moderate and runoff is medium or high.
USE AND VEGETATION: Used mainly for grazing, wildlife, and recreation. Native vegetation is big bluestem, little bluestem, sideoats grama, hairy grama, leadplant, and yucca. Most areas have a sparse overstory of ponderosa pine.
DISTRIBUTION AND EXTENT: Mountainuous areas of the Black Hills in South Dakota. It is of small extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Denver, Colorado
SERIES ESTABLISHED: Custer County, South Dakota, 1985.
REMARKS: Diagnostic horizons and features recognized in this pedon are: mollic epipedon - the zone from the surface to about 7 inches mixed (A horizon); argillic horizon - the zone from about 6 to 18 inches (Bt1 and Bt2 horizons).