LOCATION KEOTA CO+NE SD WYEstablished Series
TAXONOMIC CLASS: Coarse-silty, mixed, superactive, calcareous, mesic Ustic Torriorthents
TYPICAL PEDON: Keota loam, grassland. (Colors are for dry soil unless otherwise noted)
A--0 to 4 inches; light brownish gray (10YR 6/2) loam, dark grayish brown (10YR 4/2) moist; moderate very fine granular structure; soft, very friable, slightly sticky and slightly plastic; calcareous; moderately alkaline (pH 8.2); clear smooth boundary. (3 to 6 inches thick)
AC--4 to 10 inches; light brownish gray (10YR 6/2) loam, dark grayish brown (10YR 4/2) moist; very weak coarse prismatic structure parting to weak coarse and medium subangular blocky; slightly hard, very friable, slightly sticky and slightly plastic; calcareous; moderately alkaline (pH 8.4); gradual smooth boundary. (4 to 8 inches thick)
C1--10 to 24 inches; very pale brown (10YR 7/3) loam, brown (10YR 5/3) moist; massive; slightly hard, very friable, slightly sticky and slightly plastic; some visible secondary calcium carbonate as soft concretions; 10 percent weathered Brule bedrock fragments with the amount of fragments increasing in the lower part of the horizon; calcareous; moderately alkaline (pH 8.4); clear smooth boundary. (13 to 26 inches thick)
C2r--24 to 40 inches; consolidated Brule silt stone.
TYPE LOCATION: Logan County, Colorado; approximately 2,250 feet west and 2,225 feet north of the southeast corner of sec. 36, T. 11 S., R. 52 W.
RANGE IN CHARACTERISTICS: Usually these soils are calcareous throughout but depth to uniformly calcareous material ranges from 0 to 10 inches. Depth to the paralithic contact ranges from 20 to 40 inches. The particle-size control section is typically loam or silt loam but clay ranges from 5 to 18 percent, silt from 30 to 70 percent, and sand from 12 to 50 percent. Exchangeable sodium ranges from 0 to 15 percent, and conductivity ranges from 0 to 14 millimhos/cm in a major part of the control section. Continuous subhorizons of secondary calcium carbonate and/or sulfate do not occur within the control section although some visible accumulation occurs in some pedons. Cation exchange capacity ranges from 100 to 400 milliequivalents per 100 grams of clay, and there is some volcanic ash and glass throughout the fine earth in the control section. Rock fragments are mainly 1/8 to 1/2 inch in diameter. A majority of subhorizons above the bedrock have hue of 7.5YR or yellower. The control section of some pedons has a few faint redoximorphic features and the chroma of both the matrix and redoximorphic features exceeds 2.
The A horizon has hue of 2.5Y, 10YR or 7.5YR, value of 5 to 8 dry and 3 to 7 moist, and chroma from 1 to 4. It is slightly alkaline or moderately alkaline.
The C horizon has hue of 2.5Y, 10YR or 7.5YR. It is moderately alkaline or strongly alkaline. Calcium carbonate equivalent of the fine earth ranges from 4 to 14 percent.
COMPETING SERIES: These are the Mitchell series (it is assumed the Mitchell series is competing pending an update in the classification). Mitchell soils lack bedrock above a depth of 40 inches.
GEOGRAPHIC SETTING: Keota soils are on hills and ridges. Slopes range from 0 to 45 percent. The soils formed in, calcareous, silty and loamy materials weathered residually or only locally transported from exposures of Brule deposits. At the type location, the mean annual precipitation is about 15 inches with peak periods of precipitation occurring in the spring and early summer months. Mean annual air temperature is 48 degrees F., mean summer temperature is 73 degrees F.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the competing Mitchell soils and the Epping soils. Epping soils have bedrock at a depth of 10 to 20 inches.
DRAINAGE AND PERMEABILITY: Well drained. Medium or rapid runoff. Moderate or moderately slow permeability.
USE AND VEGETATION: These soils are used as grazing land and as dry or irrigated cropland. Native vegetation is sage, cactus, blue grama and western wheatgrass.
DISTRIBUTION AND EXTENT: Eastern Colorado and Wyoming and western Nebraska and South Dakota. The series is of large extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Denver, Colorado
SERIES ESTABLISHED: Mellette County, South Dakota, 1971.
REMARKS: Some laboratory data indicates the soil has a calcic horizon and would classify as Ustic Haplocalcids.
ADDITIONAL DATA: Laboratory data - S64NE045-003, S53NE157-003, S53NE157-005, S50WY015-001, S53WY015-001 and S53WY015-002.