LOCATION DURRSTEIN SDEstablished Series
TAXONOMIC CLASS: Fine, smectitic, mesic Vertic Natraquolls
TYPICAL PEDON: Durrstein silt loam - on a slope of less than 1 percent under native grass. When described the soil was moist to 3 inches. (Colors are for dry soil unless otherwise stated)
E--0 to 3 inches; dark gray (10YR 4/1) silt loam, gray (10YR 6/1) dry; weak medium platy structure parting to weak fine granular; soft, friable; many roots; neutral; abrupt smooth boundary. (1 to 4 inches thick)
Btn1--3 to 8 inches; black (10YR 2/1) clay, dark gray (10YR 4/1) dry; moderate medium columnar structure parting to strong fine blocky and subangular blocky; very hard, very firm; moderately alkaline; clear smooth boundary.
Btn2--8 to 11 inches; very dark grayish brown (10YR 3/2) silty clay, grayish brown (10YR 5/2) dry; weak coarse prismatic structure parting to moderate medium subangular blocky; very hard, very firm; moderately alkaline; clear smooth boundary. (Combined Btn horizons 5 to 27 inches thick)
Bzg--11 to 16 inches; very dark grayish brown (2.5Y 3/2) silty clay, grayish brown (2.5Y 5/2) dry; few fine distinct olive brown (2.5Y 4/4) redox concentrations; moderate coarse subangular blocky structure; very hard, firm; few fine striations and nests of salts; slight effervescence; moderately alkaline; clear smooth boundary. (0 to 17 inches thick)
Bkzg--16 to 42 inches; dark gray (5Y 4/1) and gray (5Y 5/1) silty clay, gray (5Y 5/1 and 6/1) dry; few fine prominent olive brown (2.5Y 4/4) redox concentrations; weak medium and coarse subangular blocky structure; very hard, firm; common fine striations and nests of salts; common fine accumulations of carbonate; slight effervescence; moderately alkaline; abrupt smooth boundary. (18 to 44 inches thick)
Cg--42 to 60 inches; dark olive gray (5Y 3/2) silty clay, olive gray (5Y 5/2) dry; common fine prominent olive brown (2.5Y 4/4) redox concentrations; weak medium subangular blocky structure; hard, firm; slight effervescence; moderately alkaline.
TYPE LOCATION: Sully County, South Dakota; about 1.5 miles east and 2.5 miles north of Agar; 1696 feet south and 279 feet west of the northeast corner of sec. 8, T. 116 N., R. 75 W.
RANGE IN CHARACTERISTICS: The depth to accumulations of salts ranges from 5 to 15 inches and the SAR ranges from 13 to 25. The soils can contain up to 5 percent by volume of pebbles and more than 15 percent fine sand or coarser.
Some pedons have an A horizon 2 inches thick or less.
The E horizon has value of 3 or 4, and 5 or 6 dry, and chroma of 1 or 2. It typically is silt loam, but is loam in some pedons. It is slightly acid or neutral.
The Btn horizon has hue of 10YR or 2.5Y, value of 2 to 3, and 3 to 6 dry, and chroma of 1 or 2. Some pedons have moist value of 4 in the lower part. It is clay, clay loam, or silty clay averaging between 35 and 60 percent clay and more than 15 percent fine sand and coarser. It ranges from neutral to moderately alkaline in the upper part and slightly alkaline to strongly alkaline in the lower part. Some pedons have Btnz or Btnkz horizons.
The Bzg and Bkzg horizons have hue of 10YR, 2.5Y or 5Y, value of 2 to 5 and 5 or 6 dry, and chroma of 1 or 2. They are silty clay, clay loam, silty clay loam, or clay. They have few or common accumulations of salts and are slightly alkaline to strongly alkaline.
The Cg horizon has hue of 2.5Y or 5Y, value of 3 to 6 and 4 to 7 dry, and chroma of 1 or 2. It typically is clay, silty clay, clay loam, or silty clay loam, but is stratified with coarser material below 40 inches in some pedons. It ranges from slightly alkaline to very strongly alkaline. Buried horizons are common below depths of 40 inches. Most pedons have few to many, faint to prominent redox features in the Bzg, Bkzg, and Cg horizons. Some pedons have textures of sand to fine sandy loam below depths of 40 inches and some pedons contain up to 50 percent by volume of pebbles.
COMPETING SERIES: These are the Hoven and Thunderegg (as previously classified) series. Hoven soils are leached of salts to depths greater than 15 inches. Thunderegg soils have sand and gravel at depths of 25 to 50 inches.
GEOGRAPHIC SETTING: Durrstein soils are on level bottomlands along the larger drainageways and broad flats in glacial till plains. Slope gradients are less than 1 percent. Surfaces are plane or concave. These soils formed in clayey alluvium. Mean annual air temperature ranges from 45 to 52 degrees F, and the mean annual precipitation ranges from 17 to 26 inches.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the competing Hoven soils and the Bon, Egas and Farmsworth. Hoven soils are in depressions. Bon soils do not have a natric horizon and are on higher positions in the landscape. Egas soils do not have a natric horizon and are on slightly higher positions in the micro-relief. Farmsworth soils have thicker surface horizons and are leached of salts to greater depths and are on slightly higher positions in the micro-relief.
DRAINAGE AND PERMEABILITY: Poorly drained. Runoff is negible to high depending on slope. Permeability is very slow or slow. It has a water table that typically fluctuates between 1 and 6 feet, but is at the surface during the spring of most years and the soil is saturated to the surface.
USE AND VEGETATION: Used mainly as native rangeland and hayland. Native vegetation includes western wheatgrass, alkali cordgrass, inland saltgrass, and nuttail alkaligrass.
DISTRIBUTION AND EXTENT: Central and south-central South Dakota. The series is of moderate extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: St. Paul, Minnesota
SERIES ESTABLISHED: Hughes County, South Dakota, 1970.
REMARKS: Diagnostic horizons and features recognized in this pedon are: mollic epipedon - the zone from the surface of the soil to a depth of 16 inches (E, Btn1, Btn2, Bzg horizons); natric horizon - the zone from a depth of 3 to 11 inches (Btn1 and Btn2 horizons).