LOCATION SELMAN OKEstablished Series
TAXONOMIC CLASS: Fine-silty, mixed, superactive, thermic Typic Argiustolls
TYPICAL PEDON: Selman silt loam, on a smooth convex 2 percent slope, in cropland. (Colors are for dry soil unless otherwise stated.)
Ap--0 to 2 inches; brown (7.5YR 4/3), rubbed, silt loam, dark brown (7.5YR 3/3), rubbed, moist; weak fine granular structure; slightly hard, very friable; common fine and medium roots throughout; noneffervescent (HCl, unspecified); moderately acid; abrupt smooth boundary. (2 to 18 inches thick)
Ad--2 to 5 inches; brown (7.5YR 4/3), rubbed, silt loam, dark brown (7.5YR 3/3), rubbed, moist; moderate medium platy structure; very hard, very firm; common fine roots throughout and common fine in mat at top of horizon; common very fine moderate continuity vesicular pores; noneffervescent (HCl, unspecified); strongly acid; abrupt smooth boundary. (0 to 5 inches thick)
BA--5 to 16 inches; brown (7.5YR 4/3), rubbed, silt loam, dark brown (7.5YR 3/3), rubbed, moist; weak medium prismatic structure parting to moderate fine and medium subangular blocky; hard, friable; common very fine and fine roots throughout; common fine continuous tubular pores and few medium continuous tubular pores; few fine irregular calcium carbonate threads between peds; many fine irregular worm casts throughout; violently effervescent throughout (HCl, unspecified); moderately alkaline; clear smooth boundary. (6 to 11 inches thick)
Btk1--16 to 24 inches; light brown (7.5YR 6/4), broken face, silt loam, brown (7.5YR 4/4), broken face, moist; moderate medium prismatic structure parting to moderate medium subangular blocky; hard, friable; common very fine and fine roots throughout; common medium continuous tubular pores and common medium interstitial pores; very few faint discontinuous clay films on faces of peds and in pores; common fine calcium carbonate threads between peds; common fine irregular worm casts throughout; violently effervescent throughout (HCl, unspecified); moderately alkaline; gradual smooth boundary. (6 to 31 inches thick)
Btk2--24 to 34 inches; reddish yellow (5YR 6/6), broken face, silty clay loam, yellowish red (5YR 5/6), broken face, moist; moderate medium prismatic structure parting to moderate medium subangular blocky; hard, friable; common very fine and fine roots throughout; common medium continuous tubular pores and common medium interstitial pores; very few faint discontinuous clay films in root channels and/or pores; common medium irregular calcium carbonate nodules between peds; violently effervescent throughout (HCl, unspecified); moderately alkaline; gradual smooth boundary. (10 to 17 inches thick)
Btk3--34 to 51 inches; yellowish red (5YR 5/6), broken face, silt loam, yellowish red (5YR 4/6), broken face, moist; moderate coarse prismatic structure parting to moderate medium subangular blocky; hard, friable; common very fine and fine roots throughout; few medium continuous tubular pores and common fine continuous tubular pores; very few faint discontinuous clay films in root channels and/or pores; common fine and medium irregular calcium carbonate threads throughout; few medium irregular calcium carbonate nodules throughout; violently effervescent throughout (HCl, unspecified); moderately alkaline; abrupt smooth boundary. (10 to 17 inches thick)
BCk--51 to 61 inches; yellowish red (5YR 5/6), broken face, silt loam, yellowish red (5YR 4/6), broken face, moist; weak coarse prismatic structure parting to massive; hard, friable; common very fine and fine roots throughout; common very fine and fine continuous tubular pores; common fine and medium irregular soft masses of calcium carbonate throughout; few medium irregular calcium carbonate nodules throughout; violently effervescent throughout (HCl, unspecified); moderately alkaline; abrupt smooth boundary. (10 to 15 inches thick)
C--61 to 80 inches; yellowish red (5YR 5/6), broken face, silt loam, yellowish red (5YR 4/6), broken face, moist; massive; hard, friable; common very fine and fine roots throughout; common very fine and fine continuous tubular pores; few coarse irregular soft masses of calcium carbonate throughout; violently effervescent throughout (HCl, unspecified); moderately alkaline. (17 to 30 inches thick)
TYPE LOCATION: Harper County, Oklahoma; 0.5 mile north and 2.5 miles west of the town of Selman. 2650 feet west and 650 feet north of the southeast corner sec. 14, T. 27 N., R. 22 W. Latitude: 36 degrees, 48 minutes, 50 seconds North; Longitude: 99 degrees, 32 minutes, 20 seconds West.
RANGE IN CHARACTERISTICS: Solum thickness is greater than 50 inches. Depth to secondary carbonates ranges from 9 to 30 inches. Depth to nonparalithic bedrock is greater than 60 inches.
The A horizon has hue of 5YR to 7.5YR, value of 3 or 4 and chroma of 2 or 3. It is silt loam, loam or very fine sandy loam.
Where present, the Ad horizon, has hue of 5YR to 7.5YR, value of 3 or 4 and chroma of 2 or 3. It is very fine sandy loam, loam, or silt loam.
The BA horizon has hue of 5YR to 7.5YR, value of 4 and chroma of 3 or 4. It is silt loam, loam or very fine sandy loam.
The Btk1 horizon has hue of 5YR to 7.5YR, value of 4 to 7 and chroma of 3 to 8. It is silt loam, silty clay loam or clay loam.
The Btk2 horizon has hue of 2.5YR to 7.5YR, value of 4 or 5 and chroma of 3 to 6. It is silt loam, silty clay loam or loam.
The Btk3 horizon has hue of 2.5YR to 5YR, value of 4 or 5 and chroma of 4 to 6. It is silt loam or silty clay loam.
The BCk horizon has hue of 2.5YR to 5YR, value of 5 or 6 and chroma of 6 to 8. It is silt loam or loam.
The C horizon has hue of 2.5YR to 5YR, value of 5 or 6 and chroma of 6 to 8. It is silt loam or loam.
Where present, the Cr horizon is weakly cemented sandstone with excavation difficulty is low to moderate.
COMPETING SERIES: This is the Carey series. Carey soils are warmer and drier for longer periods.
GEOGRAPHIC SETTING: These soils are on stream terraces and old dissected terraces on uplands. Slope gradients range from 0 to 8 percent. The soils formed in materials weathered from silty or sandy Permian redbeds. The climate is dry subhumid with annual precipitation of 22 to 28 inches and Thornthwaite annual P-E indices of 34 to 44. Mean annual temperatures range from 57 degrees to 62 degrees F. The frost free period ranges from 190 to 225 days. Elevation ranges from 1500 to 2200 feet.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the competing Carey series and the Deepwood, Paducah, Quinlan, St. Paul, Tipton and Woodward series. Paducah, St. Paul, and Tipton soils are on similar areas. St. Paul and Tipton soils have mollic epipedons greater than 20 inches thick. In addition Tipton soils are fine loamy. Paducah soils do not have mollic epipedons. Deepwood, Quinlan and Woodward soils occur on positions. In addition, Deepwood, Quinlan and Woodward lack mollic epipedons and lack Bt horizons.
DRAINAGE AND PERMEABILITY: Well drained, negligible to medium surface runoff; moderately permeable.
USE AND VEGETATION: Most areas are cultivated to wheat and grain sorghum. Some areas remain in rangeland and support stands of blue grama, buffalograss, little bluestem, sand bluestem, switchgrass, and sideoats grama.
DISTRIBUTION AND EXTENT: The Central Rolling Red Plains (MLRA 78C) of Oklahoma, Texas, and Kansas. The series is moderately extensive.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Temple, Texas
SERIES ESTABLISHED: Woods County, Oklahoma; 1995.
REMARKS: Soil Interpretation Record: Series OK0446.
These soils were formerly included in the Carey series.
Diagnostic horizons and features:
Mollic epipedon - The zone from the soil surface to a depth of 16 inches.
Argillic horizon - The zone from approximately 16 inches to 51 inches (Bt horizon).