LOCATION STETTER SD+WYEstablished Series
TAXONOMIC CLASS: Fine, smectitic, nonacid, mesic Torrertic Ustifluvents
TYPICAL PEDON: Stetter clay - on a plane slope of less than l percent in native grass. When described the soil was dry throughout. (Colors are for dry soil unless otherwise stated)
A--0 to 3 inches; grayish brown (2.5Y 5/2) clay, dark grayish brown (2.5Y 4/2) moist; weak fine platy structure; very hard, very firm, sticky and plastic; neutral; clear smooth boundary. (2 to 6 inches thick)
C--3 to 60 inches; grayish brown (2.5Y 5/2) clay, dark grayish brown (2.5Y 4/2) moist; massive; very hard, very firm, sticky and plastic; thin strata of vari-colored soil materials; slightly alkaline.
TYPE LOCATION: Butte County, South Dakota; about 3 miles east and 5 miles north of Newell; 2,000 feet east and 75 feet north of the southwest corner of sec. 26, T. l0 N., R. 6 E.
RANGE IN CHARACTERISTICS: These soils typically lack carbonates throughout, but some pedons have thin strata that contain carbonates and have carbonates within 15 inches of the surface. The particle-size control section averages between 45 and 60 percent clay. When the soil is dry, cracks l/2 to 2 inches wide and several feet long extend to depths of 4 feet or more. These soils formed in alluvium that has evident stratification. Thin dark-colored strata and buried horizons are common. Some pedons have thin strata of sand or silt. Rock fragments range from 0 to 5 percent.
The A horizon has hue of 2.5Y or 5Y, value of 4 to 6 and 3 to 5 moist, and chroma of 1 or 2. Where it has a color value of 5.5 or less dry and 3.5 or less moist it is too thin for a mollic epipedon. The A horizon typically is clay but some pedons are silty clay or silty clay loam. It is slightly acid to moderately alkaline. Some pedons have varved or platy layers of recent deposition on the surface.
The C horizon has hue of 2.5Y or 5Y, value of 4 to 6 and 3 to 5 moist, and chroma of l or 2. The dark colors are inherent from the parent material. The C horizon is clay or silty clay. It is neutral to moderately alkaline. It has weak blocky structure or is massive, and some pedons have unaltered horizontal bedding planes. The material below depths of 40 inches ranges from loamy sand through clay and includes bedded shale.
COMPETING SERIES: There are no other series in the family.
GEOGRAPHIC SETTING: Stetter soils are nearly level on floodplains and bottom lands along present day streams. Slope gradient is less than 3 percent. They formed in clayey alluvium derived from clay shales. Mean annual air temperature ranges from 43 to 48 degrees F., and mean annual precipitation from l4 to l8 inches.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Arvada, Haverson, Kyle, Lohmiller, Swanboy, Wasa and Winler soils. Arvada, Kyle and Swanboy Arvada soils are on terraces and fans. Arvada soils have natric horizons. Kyle and Swanboy soils have cambic horizons. Haverson and Lohmiller soils are on similar bottom lands. Haverson soils are fine-loamy. Lohmiller soils contain from 35 to 45 percent clay and contain free carbonates. The Wasa and Winler soils are on the nearby uplands and have bedded shale within depths of 40 inches.
DRAINAGE AND PERMEABILITY: Well drained. Surface runoff is low to medium depending on slope. Permeability is slow or very slow. These soils are occasionally or frequently flooded.
USE AND VEGETATION: Rangeland and native hay production. Western wheatgrass is the dominant grass and other vegetation is big bluestem, green needlegrass, sedges, and shrubs. Trees frequently are along the stream channel.
DISTRIBUTION AND EXTENT: Western South Dakota and possibly adjoining states. The series is of moderate extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Denver, Colorado
SERIES ESTABLISHED: Butte County, South Dakota, 3/70.
REMARKS: Diagnostic horizons and features recognized in this pedon: Ochric epipedon - the zone from the surface of the soil to a depth of 3 inches (A horizon).