LOCATION FIRESTEEL SDEstablished Series
TAXONOMIC CLASS: Fine-silty, mesic Aeric Calciaquolls
TYPICAL PEDON: Firesteel silt loam on a plane slope of 1 percent in a cultivated field. (Colors are for moist soil unless otherwise stated.)
Ap--0 to 7 inches; very dark gray (10YR 3/1) silt loam, gray (10YR 5/1) dry; weak fine granular structure; soft, very friable; strong effervescence (45 percent calcium carbonate); moderately alkaline; abrupt smooth boundary. (6 to 9 inches thick)
Bk--7 to 15 inches; dark grayish brown (2.5Y 4/2) and grayish brown (2.5Y 5/2) silt loam, gray (2.5Y 6/1) and light gray (2.5Y 7/1) dry; weak medium and coarse prismatic structure parting to weak medium subangular blocky; soft, very friable; few gypsum crystals; violent effervescence (65 percent CaCO3); strongly alkaline; clear wavy boundary. (8 to 16 inches thick)
Bky--15 to 30 inches; light yellowish brown (2.5Y 6/3) silt loam, white (2.5Y 8/2) dry; weak fine and medium subangular blocky structure; slightly hard, friable; common gypsum crystals; common medium accumulations of carbonate; violent effervescence (65 percent CaCO3); strongly alkaline; gradual wavy boundary. (0 to 15 inches thick)
Cr--30 to 60 inches; pale yellow (5Y 7/3) siltstone, white (5Y 8/2) dry; thick platy bedrock structure; many gypsum crystals; violent effervescence (90 percent calcium carbonate); strongly alkaline.
TYPE LOCATION: Davison County, South Dakota; about 3 miles east and 4 1/2 miles north of Mount Vernon; 1,580 feet north and 72 feet east of the southwest corner of sec. 31, T. 104 N., R. 61 W.
RANGE IN CHARACTERISTICS: Depth to siltstone ranges from 24 to 40 inches. A thin mantle of loamy glacial sediments is at the surface of some pedons. Clay content of the control section ranges from 20 to 30 percent. The soil ranges from mildly alkaline to strongly alkaline throughout.
The A horizon has hue of 10YR or 2.5Y, value of 2 or 3 and 3 to 5 dry, and chroma of 1 or 2. It is silt loam or loam.
The Bk horizon has hue of 10YR or 2.5Y, value of 4 or 5 and 5 to 7 dry, and chroma of 1 or 2. It is silt loam or silty clay loam.
The Bky horizon has hue of 2.5Y or 5Y, value of 6 to 8 and 7 or 8 dry, and chroma of 2 to 4. Gypsum crystals are common or many. Small siltstone fragments are in some pedons. Calcium carbonate equivalent ranges from 40 to 70 percent. Some pedons have a C horizon.
The Cr horizon has color ranges similar to the Bky horizon. It is soft siltstone having thicky platy bedrock structure. Calcium carbonate equivalent ranges from 50 to 90 percent.
COMPETING SERIES: There are no other series in this family.
GEOGRAPHIC SETTING: Firesteel soils are on terraces, swales, and footslopes. Slope gradients range from 0 to 2 percent. Surfaces are plane or concave. These soils formed in residuum weathered from siltstone. The mean annual temperature ranges from 45 to 50 degrees F, and the mean annual precipitation ranges from 17 to 24 inches.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Betts, Blendon, Bon, Clarno, Enet, Ethan, Gavins, Houdek, Redstoe, and Prosper soils. The well drained Betts, Ethan, and Gavins soils are on steeper parts of the landscape. Blendon, Bon, and Prosper soils are on similar landscapes. Blendon soils are coarse-loamy and do not have Cr horizons of siltstone. Bon and Prosper soils are fine-loamy, have mollic epipedons greater than 20 inches thick, and do not have Cr horizons of siltstone. Enet soils are on similar landscapes, are moderately deep over sand and gravel, and are better drained. Clarno and Houdek soils are fine-loamy and formed in glacial till on higher landscapes. Redstoe soils are on nearby uplands and are better drained.
DRAINAGE AND PERMEABILITY: Somewhat poorly drained. Runoff is low. Permeability is moderate.
USE AND VEGETATION: About one-half of the acreage of these soils are cultivated. Alfalfa, small grains, and forage crops are the principal crops. Native vegetation is mainly big bluestem, little bluestem, western wheatgrass, sideoats grama, needleandthread, blue grama, sedges, and forbs.
DISTRIBUTION AND EXTENT: South-central South Dakota, east of the Missouri River. The series is inextensive.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: St. Paul, Minnesota
SERIES ESTABLISHED: Davison County, South Dakota, 1976.
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 7 inches (Ap horizon).