LOCATION CORBIN KS+OKEstablished Series
TAXONOMIC CLASS: Fine-silty, mixed, active, thermic Pachic Argiustolls
TYPICAL PEDON: Corbin silt loam - cultivated. (Colors are for dry soil unless otherwise stated.)
A--0 to 12 inches; dark grayish brown (10YR 4/2) silt loam, very dark grayish brown (10YR 3/2) moist; weak fine granular structure; slightly hard, friable; slightly acid; gradual smooth boundary. (10 to 16 inches thick)
Bt1--12 to 31 inches; dark brown (7.5YR 4/3) silty clay loam, dark brown (7.5YR 3/2) moist; moderate medium and fine subangular blocky structure; hard, friable; faint clay films on some faces of peds; neutral; clear smooth boundary. (10 to 24 inches thick)
2Bt2--31 to 44 inches; dark grayish brown (10YR 4/2) clay, very dark grayish brown (10YR 3/2) moist; moderate medium blocky structure; very hard, very firm; distinct continuous clay films; neutral; clear smooth boundary. (8 to 20 inches thick)
2Bt3--44 to 60 inches; dark brown (10YR 4/3) clay, dark brown (10YR 3/3) moist; moderate coarse blocky structure; very hard, very firm; neutral; soil mass mostly lacks free carbonates but contains many fine calcareous accumulations; mildly alkaline; gradual smooth boundary. (10 to 24 inches thick)
2C--60 to 70 inches; brown (7.5YR 5/3) silty clay loam, dark brown (7.5YR 4/3) moist; massive; very hard, firm; mildly alkaline.
TYPE LOCATION: Harper County, Kansas; about 8.5 miles east and 1 mile south of Anthony, Kansas; 145 feet south and 1,320 feet east of the northwest corner of sec. 34, T. 33 S., R. 5 W.
RANGE IN CHARACTERISTICS: The thickness of solum ranges from about 40 to 70 inches or more. The A horizon ranges from medium acid to neutral. The Bt horizon is slightly acid or neutral, and the lower 2Bt and C horizons are neutral or mildly alkaline. Depth to free carbonates ranges from about 40 to 70 or more inches.
The A horizon has hue of 10YR or 7.5YR, value of 3 to 5 and 2 or 3 moist, and chroma of 2 or 3. It is typically silt loam and less commonly loam or clay loam.
The Bt horizon has hue of 7.5YR or 10YR, value of 3 to 5 and 2 or 3 moist, and chroma of 2 to 4. The upper 20 inches of the argillic horizon average between 27 and 35 percent clay and contain less than 15 percent of fine or coarser sand. Faint mottles are above the 2Bt horizon in some pedons but are at depths greater than 20 inches.
The 2Bt horizon has hue of 10YR or 7.5YR, value of 3 to 5 and 3 or 4 moist, and chroma of 2 or 3. It is clay or silty clay. The top of the 2Bt horizon is within depths of 40 inches.
The 2C horizon has hue of 10YR or 7.5YR, value of 4 to 6 and 3 to 5 moist, and chroma of 2 to 4. It is silty clay loam or silty clay.
COMPETING SERIES: These are the Pond Creek, St. Paul, and Westview series in the same family and the Bethany, Farnum, Grant, Kirkland, Norge, Tabler, Teller, and Vanoss series. Pond Creek, Grant, Norge, Teller, and Westview soils lack clay or silty clay lower Bt horizons. St. Paul soils have formed in residuum from silt beds and have redder hue. The Bethany, Kirkland and Tabler soils are fine. The Farnum soils are fine-loamy. Vanoss soils have a mollic epipedon less than 20 inches thick.
GEOGRAPHIC SETTING: Corbin soils are on nearly level and gently sloping uplands. The soil formed in loess and old alluvium. Slope gradients range from 0 to 3 percent. Mean annual precipitation ranges from 25 to 35 inches. Mean annual temperature at the type location is about 58 degrees F. Thornthwaites Annual PE Index ranges from 44 to 60.
GEOGRAPHICALLY ASSOCIATED SOILS: These include the competing Bethany, Kirkland, Pond Creek, and Tabler soils. All are on similar topography.
DRAINAGE AND PERMEABILITY: Well drained. Runoff is slow. Permeability is moderate in the B horizons and slow in the 2B horizons.
USE AND VEGETATION: Principally cultivated to wheat, sorghums and alfalfa. Vegetation in uncultivated areas is tall prairie grasses.
DISTRIBUTION AND EXTENT: South-central Kansas and north-central Oklahoma. The series is inextensive.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Temple, Texas
SERIES ESTABLISHED: Harper County, Kansas, 1970.