LOCATION WINSHIP SDEstablished Series
TAXONOMIC CLASS: Fine-silty, mixed, superactive, frigid Pachic Argiudolls
TYPICAL PEDON: Winship silt loam - on a nearly level, plane slope of less than 1 percent in a flat drainageway in a plowed field. When described, the soil was moist throughout. (Colors are for dry soil unless otherwise stated.)
Ap--0 to 7 inches; dark gray (10YR 4/1) silt loam, black (10YR 2/1) moist; weak fine granular structure; slightly hard, very friable, common very fine and fine roots; slightly alkaline; abrupt smooth boundary.
A--7 to 22 inches; dark gray (10YR 4/1) silt loam, black (10YR 2/1) moist; weak coarse subangular blocky structure parting to weak fine granular; slightly hard, very friable, common very fine and fine roots; slightly alkaline; clear wavy boundary. (Combined thickness of A horizons is 15 to 27 inches.)
BA--22 to 33 inches; gray (10YR 5/1) silty clay loam, black (10YR 2/1) moist; weak fine prismatic structure parting to weak fine subangular blocky; hard, friable, slightly sticky and slightly plastic; few fine roots; light gray (10YR 6/1) coatings on surface of peds; neutral; clear smooth boundary. (7 to 15 inches thick)
Bt1--33 to 40 inches; gray (10YR 5/1) silty clay loam, very dark gray (10YR 3/1) moist; weak medium prismatic structure parting to moderate medium and fine blocky; hard, friable, slightly sticky and slightly plastic; light gray (10YR 6/1) coatings on surface of peds; neutral; clear wavy boundary.
Bt2--40 to 48 inches; light brownish gray (2.5Y 6/2) silty clay loam, dark grayish brown (2.5Y 4/2) moist; common medium distinct dark yellowish brown (10YR 4/4) redox concentrations; weak fine subangular blocky structure; hard, friable, slightly sticky and slightly plastic; neutral; gradual wavy boundary. (Combined thickness of Bt horizons is 10 to 30 inches.)
C-48 to 60 inches; light gray (2.5Y 7/2) silt loam, grayish brown (2.5Y 5/2) moist; many medium distinct yellowish brown (10YR 5/4) redox concentrations; massive; hard, friable, slightly sticky and slightly plastic; varved; mildly alkaline.
TYPE LOCATION: Brown County, South Dakota; about 4 miles north and 3 miles west of Groton; 1,860 feet west and 1,190 feet north of the southeast corner, sec. 27, T. 124 N., R. 61 W.
RANGE IN CHARACTERISTICS: The thickness of the mollic epipedon ranges from 32 to more than 60 inches. The depth to free carbonate ranges from 40 to 60 inches or more.
The A horizon has hue of 10YR, value of 3 or 4 and 2 or 3 moist, and chroma of 1. It typically is silt loam, but is silty clay loam in some pedons. It ranges from slightly acid to slightly alkaline.
The BA horizon has hue of 10YR, value of 4 to 6 and 2 or 3 moist, and chroma of 1 or 2. It is silt loam or silty clay loam. It typically has light gray (10YR 6/1) coatings on the surface of peds. It is neutral or slightly alkaline.
The Bt horizon has hue of 10YR or 2.5Y, value of 4 to 6 and 2 to 4 moist, and chroma of 1 or 2. It is silty clay loam and averages 27 to 35 percent clay. It typically has light gray (10YR 6/1) coatings on the surface of peds in the upper part. It is neutral or slightly alkaline.
A BC or Bk horizon is present in some pedons.
The C horizon has hue of 10YR to 5Y, value of 5 to 7 and 4 to 6 moist, and chroma of 2 or 3. It is silt loam or silty clay loam. Redox concentrations range from common to many, fine to medium, faint to distinct. It ranges from neutral to moderately alkaline. Loamy glacial till is below a depth of 40 inches in some pedons. Some pedons have varves below a depth of 40 inches.
COMPETING SERIES: These are the Barfus series in the same family and the Harmony, Hidewood, Parnell, and Tonka series. Barfus soils have carbonates throughout and are well drained. Harmony soils are fine-textured and are moderately well drained. Hidewood soils do not have an argillic horizon and have carbonates above a depth of 40 inches. Parnell and Tonka soils are fine textured and are more poorly drained.
GEOGRAPHIC SETTING: Winship soils are in shallow depressions and flat drainageways in glacial lake plains. Slope gradients generally are less than 1 percent but do go up to 2 percent. The soils formed in silty alluvial deposits and glaciolacustrine sediments. The mean annual air temperature ranges from 38 to 45 degrees F, and mean annual precipitation ranges from 16 to 24 inches.
GEOGRAPHIC SETTING SOILS: They are the competing Harmony and Tonka soils, and the Aberdeen, Bearden, Beotia, and Great Bend soils. Tonka soils are in closed depressions. The Aberdeen and Harmony soils are on broad smooth flats on nearby landscapes. Aberdeen soils have a natric horizon. Bearden soils have a calcic horizon within a depth of 16 inches, and are on slightly convex slopes along depressions and drainageways. Beotia and Great Bend soils are better drained and are on higher positions on adjacent landscapes.
DRAINAGE AND PERMEABILITY: Somewhat poorly drained. Surface runoff is negligible to low and ponded in the depressional phase. During the growing season, the water table is 2 feet to 4 feet in the spring and early summer. In years of excess rainfall or snowmelt, some areas of these soils are temporarily ponded. Permeability is moderately slow in the solum and moderately slow to slow in the substratum.
USE AND VEGETATION: Soils are cropped to corn, small grains, sunflowers, and alfalfa. Native vegetation is big bluestem, switchgrass, little bluestem, needlegrass, and sedges.
DISTRIBUTION AND EXTENT: Northeastern South Dakota. These soils are of small extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: St. Paul, Minnesota
SERIES ESTABLISHED: Brown County, South Dakota, 1987.
REMARKS: Diagnostic horizons and features recognized in this pedon are: mollic epipedon - the zone from the surface of the soil to a depth of about 40 inches (Ap, A, BA, Bt1 horizons); argillic horizon - the zone from about 33 to 48 inches (Bt1, Bt2 horizons).
ADDITIONAL DATA: NSSL Sample Nos. 83P46-51.