LOCATION RELIANCE SD+NEEstablished Series
TAXONOMIC CLASS: Fine, smectitic, mesic Typic Argiustolls
TYPICAL PEDON: Reliance silty clay loam - on a northeast-facing, slightly convex slope of 2 percent in a cultivated field. When described the soil was dry throughout. (Colors are for dry soil unless otherwise stated.)
Ap--0 to 7 inches; dark grayish brown (10YR 4/2) silty clay loam, very dark brown (10YR 2/2) moist; moderate fine granular structure; hard, friable; neutral; abrupt smooth boundary. (6 to 14 inches)
Bt1--7 to 12 inches; dark grayish brown (10YR 4/2) silty clay loam, very dark grayish brown (10YR 3/2) moist; weak medium prismatic structure parting to moderate medium and fine subangular blocky; hard, firm, slightly sticky and slightly plastic; many tongues of very dark brown (10YR 2/2) moist; organic coats on faces of peds; slightly alkaline; clear wavy boundary.
Bt2--12 to 22 inches; brown (10YR 5/3) silty clay loam, dark brown (10YR 4/3) moist; weak medium prismatic structure parting to strong medium and fine blocky; hard, firm, slightly sticky and slightly plastic; clay films on faces of peds; few tongues of very dark brown (10YR 2/2) moist; slightly alkaline; abrupt wavy boundary. (Combined thickness of the Bt horizon is 8 to 22 inches)
Btk--22 to 26 inches; brown (10YR 5/3) silty clay loam, dark brown (10YR 4/3) moist; weak coarse prismatic structure parting to moderate medium and fine blocky and subangular blocky; hard, firm, slightly sticky and slightly plastic; clay films on faces of peds; few fine soft accumulations of carbonate; slight effervescence; slightly alkaline; clear wavy boundary. (0 to 6 inches thick)
Bk1--26 to 33 inches; brown (10YR 5/3) silty clay loam, dark grayish brown (10YR 4/2) moist; weak coarse prismatic structure parting to moderate medium blocky; hard, friable, slightly sticky and slightly plastic; common fine soft accumulation of carbonates; strong effervescence; moderately alkaline; clear wavy boundary.
Bk2--33 to 41 inches; pale brown (10YR 6/3) silty clay loam, dark grayish brown (10YR 4/2) moist; weak coarse prismatic structure parting to weak subangular blocky; hard, friable; common fine soft accumulations of carbonate; strong effervescence; moderately alkaline; gradual wavy boundary. (Combined Bk horizon is 7 to 20 inches thick)
C--41 to 60 inches; brown (10YR 5/3) silty clay loam, dark grayish brown (10YR 4/2) moist; massive; hard, friable; strong effervescence; moderately alkaline.
TYPE LOCATION: Gregory County, South Dakota; about 2 miles east and 1 mile south of Lucas; 110 feet north and 1,100 feet east of the southwest corner of sec. 25, T. 98 N., R. 71 W.
RANGE IN CHARACTERISTICS: The depth to carbonates is at depths of 14 to 36 inches. The mollic epipedon typically is 10 to 20 inches in thickness, but is as thin as 7 inches when eroded.
The A horizon has a hue of 10YR, value of 4 or 5 and 2 or 3 moist, and chroma of 1 or 2. It is silty clay loam or silt loam and is slightly acid or neutral.
The Bt horizon has hue of 10YR or 2.5Y, value of 4 or 5 and 2 to 4 moist, and chroma of 2 to 4. It is silty clay loam or silty clay averaging between 35 and 45 percent clay and less than 15 percent fine sand or coarser. The Bt horizon ranges from slightly acid to mildly alkaline. Some pedons do not have accumulations of carbonate in the lower Bt horizon.
The Bk horizon has hue of 10YR or 2.5Y, value of 5 to 7 and 4 to 6 moist, and chroma of 2 to 4. It is silty clay loam or silt loam. It is slightly or moderately alkaline. It has common or many fine or medium accumulations of carbonate.
The C horizon has hue of 10YR or 2.5Y, value of 5 to 7 and 4 to 6 moist, and chroma of 2 to 4. It is silt loam or silty clay loam. It is slightly or moderately alkaline. Clay, bedded shale, sand or gravel, or weakly cemented sandstone or siltstone is between depths of 40 and 60 inches in some pedons.
COMPETING SERIES: These are the Beadle, Carlson, Harney, Kirley, McClure, Mento, Peno, Raber, and Spearville soils in the same family. Beadle, Peno, and Raber soils have clay loam or clay argillic horizons and formed in glacial till. Carlson, Harney, Mento, and Spearville soils have mean annual temperatures higher than 52 degrees F. In addition, Carlson soils typically have carbonates higher in the profile and formed in calcareous residuum or old alluvium; Harney soils typically have a thicker solum; Mento soils have 5 to 15 percent exchangeable sodium in the B and C horizons; and Spearville soils typically have more clay in the argillic horizon. Kirley soils contain more sand in the series control section and formed in alluvium. McClure soils have contrasting clayey substrata between depths of 20 and 40 inches.
GEOGRAPHIC SETTING: Reliance soils are on nearly level to strongly sloping uplands and terraces. Surfaces are plane or slightly convex. Slope gradients typically are less than 6 percent, but range from 0 to 15 percent. They typically formed in loess and silty materials of mixed origin with contrasting substrata typically below depths of 5 to 10 feet, but ranging to as shallow as 40 inches. The mean annual temperature ranges from 45 to 50 degrees F. and mean annual precipitation ranges from 15 to 24 inches.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the competing McClure soils and the Agar, DeGrey, Hoven, Lowry, Millboro, Onita, Promise and Scott soils. Agar and McClure soils are in similar nearby landscapes. Agar soils have a fine-silty argillic horizon. DeGrey and Hoven soils have a natric horizon. DeGrey soils are on similar landscapes. Hoven and Scott soils are in depressions. Scott soils are more moist and pond water. Lowry soils have a coarse-silty control section and do not have an argillic horizon, and are on nearby landscapes. Millboro soils contain more clay in the series control section and typically are on landscapes below the Reliance soils. Onita soils have a mollic epipedon more than 20 inches thick and are in swales. Promise soils are in similar nearby landscapes and have a very-fine textured control section.
DRAINAGE AND PERMEABILITY: Well drained. Surface runoff is low to very high. Permeability is moderately slow.
USE AND VEGETATION: Most areas are cropped to winter wheat, corn, sorghum, and alfalfa. Native vegetation includes western wheatgrass, green needlegrass, needleandthread, sideoats grama, blue grama, big bluestem, little bluestem, porcupine grass, sedges, and forbs.
DISTRIBUTION AND EXTENT: South-central South Dakota and north central Nebraska. The series is of large extent.
MLRA OFFICE RESPONSIBLE: Bismarck, North Dakota
SERIES ESTABLISHED: Lyman County, South Dakota, 1940.
REMARKS: Diagnostic horizons and features recognized in this pedon are: mollic epipedon - the zone from the surface of the soil to a depth of 12 inches (Ap and Bt1 horizons); argillic horizon - the zone from about 7 to 26 inches (Bt1, Bt2, and Btk horizons).