LOCATION MOSHER SDEstablished Series
TAXONOMIC CLASS: Fine, smectitic, mesic Vertic Natrustolls
TYPICAL PEDON: Mosher silt loam - on a plane slope of 1 percent in native grass. When described the soil was moist below 7 inches. (Colors are for dry soil unless otherwise stated).
A--0 to 5 inches; grayish brown (10YR 5/2) silt loam, very dark gray (10YR 3/1) moist; weak medium and fine granular structure; slightly hard, very friable; neutral; clear smooth boundary. (3 to 8 inches thick)
E--5 to 8 inches; gray (10YR 5/1) silt loam, very dark gray (10YR 3/1) moist; weak medium and fine granular structure; slightly hard, very friable; neutral; abrupt wavy boundary. (2 to 6 inches thick)
Btn1--8 to 11 inches; dark gray (10YR 4/1) clay, black (10YR 2/1) moist; moderate coarse and medium columnar structure; extremely hard, very firm, sticky and plastic; tops and faces of peds coated with gray (10YR 6/1) silt grains; few distinct clay films on faces of peds; moderately alkaline; clear wavy boundary. (2 to 5 inches thick)
Btn2--11 to 16 inches; dark gray (10YR 4/1) clay loam, very dark brown (10YR 2/2) moist; weak medium prismatic structure parting to moderate medium and fine blocky; very hard, firm, sticky and plastic; few distinct clay films on faces of peds; moderately alkaline; gradual wavy boundary. (3 to 14 inches thick)
Btnz--16 to 33 inches; grayish brown (10YR 5/2) clay loam, very dark grayish brown (2.5Y 3/2) moist; moderate medium blocky and subangular blocky structure; very hard, friable, sticky and plastic; common fine accumulations of salts in the upper part, few in the lower part; slight effervescence; strongly alkaline; clear irregular boundary. (0 to 18 inches thick)
Bkz--33 to 55 inches; white (10YR 8/1) silty clay loam, light gray (10YR 7/2) moist; weak coarse subangular blocky; hard, friable, sticky and plastic; common fine accumulations of carbonates and salts; strong effervescence; strongly alkaline; gradual wavy boundary. (5 to 36 inches)
2C--55 to 60 inches; light gray (2.5Y 7/2) loamy fine sand, grayish brown (2.5Y 5/2) moist; massive; soft, very friable; moderately alkaline.
TYPE LOCATION: Bennett County, South Dakota; about 3 miles east and 1/2 mile north of Tuthill; 2585 feet north and 405 feet east of the southwest corner of sec. 23, T. 37 N., R. 35 W.
RANGE IN CHARACTERISTICS: The depth to carbonate typically ranges from 15 to 35 inches, but some pedons have carbonate at the surface. The thickness of the mollic epipedon is 7 to 20 inches or more and it extends into the Bt horizon. The natric horizon has ESP or SAR of 10 to 20. Accumulations of salts are below depths of 16 inches and are typically in the lower Bt horizon or Bk horizon. The soil particle size control section contains more than 15 percent fine sand or coarser and less than 1 percent coarse fragments.
The A horizon commonly is silt loam but in some pedons it is loam, fine sandy loam, very fine sandy loam, or silty clay loam. The A horizon has value of 4 or 5 and 2 or 3 moist, and chroma of 1 or 2. It ranges from moderately acid to slightly alkaline.
The E horizon commonly is silt loam but is loam or very fine sandy loam in some pedons. It has value of 5 to 7 and 3 or 4 moist, and chroma of 1 or 2. It ranges from moderately acid or slightly alkaline.
The Bt horizon is clay, silty clay, silty clay loam, or clay loam averaging between 35 and 60 percent clay. It has value of 3 to 6 and 2 to 4 moist, and chroma of 1 to 3. It ranges from neutral to strongly alkaline.
The Bkz horizon is silty clay loam or clay loam but is clay in some pedons. It has hue of 10YR or 2.5Y, value of 5 to 8 and 4 to 7 moist, and chroma of 1 to 4. It ranges from slightly alkaline to strongly alkaline. Some pedons have a Bkyz horizon.
The C horizon has hue of 10YR, 2.5Y, or 5Y; value of 5 to 8 and 4 to 7 moist; and chroma of 2 to 4. It is clay loam, loam, silty clay, clay or sandy clay loam and is commonly stratified with layers of loamy fine sand to clay. It ranges from slightly alkaline to strongly alkaline. Some pedons have buried horizons below 40 inches.
COMPETING SERIES: These are Cavo, DeGrey, Dudley, Dwight, Farmsworth, and Wood River soils. The Cavo, DeGrey, and Dudley soils contain 1 to 10 percent coarse fragments. In addition, DeGrey soils contain less than 15 percent fine sand and coarser. Dwight soils are less alkaline, underlain by limestone and have a warmer soil temperature control section. Farmsworth soils contain less than 15 percent fine sand and more coarser. Wood River soils have a warmer soil temperture control section and mean annual air temperature greater than 49 degrees F.
GEOGRAPHIC SETTING: Mosher soils are on flood plains, terraces and along drainageways and on foot slopes on uplands. Slope gradients typically are less than 3 percent but range up to 6 percent. Microrelief commonly is evident. Mosher soils formed in loamy alluvium. The mean annual air temperature is 45 to 50 degrees F, and the mean annual precipitation is 12 to 24 inches. Growing season ranges from 125 to 160 days; growing season precipitation is about 11 to 17 inches; growing season degree days range from 2600 to 3300.
GEOGRAPHICALLY ASSOCIATED SOILS: These are Mobridge, Onita, Ree, and Reliance soils. Mobridge, Onita, Ree and Reliance are on slightly higher positions in the same landscape and do not have a natric horizon.
DRAINAGE AND PERMEABILITY: Moderately well drained and somewhat poorly drained. Surface runoff is low or medium. Permeability is very slow. A fluctuating water table is at depths ranging from 3 to 6 feet in some pedons.
USE AND VEGETATION: Used primarily for range. Alfalfa and winter wheat are the main crops in cultivated areas. The main native grasses are western wheatgrass, green needlegrass, needleandthread, blue grama, buffalograss, and sedges.
DISTRIBUTION AND EXTENT: South-central South Dakota and northeastern Colorado and possibly northwestern Nebraska and southeastern Wyoming. The series is of moderate extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Denver, Colorado
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 about 33 inches (A, E, Btn1, Btn2, Btnz horizons); argillic horizon - the zone from about 8 to 33 inches (Btn1, Btn2, Btnz horizons). Vertic properties - linear extensibility of 6.0 cm or greater at a depth of 0 to 40 inches.