LOCATION CLARNO SD+NEEstablished Series
TAXONOMIC CLASS: Fine-loamy, mixed, superactive, mesic Typic Haplustolls
TYPICAL PEDON: Clarno loam - on a convex slope of 3 percent in a cultivated field. When described the soil was dry to a depth of 60 inches. (Colors are for dry soil unless otherwise stated.)
Ap--0 to 6 inches; dark grayish brown (10YR 4/2) loam, very dark brown (10YR 2/2) moist; weak medium and fine subangular blocky structure parting to weak fine granular; slightly hard, very friable; neutral; abrupt smooth boundary.
A--6 to 8 inches; dark grayish brown (10YR 4/2) loam, very dark brown (10YR 2/2) moist; moderate medium subangular blocky structure parting to weak fine subangular blocky; slightly hard, very friable; neutral; clear wavy boundary. (Combined A horizons is 6 to 12 inches thick.)
Bw1--8 to 12 inches; grayish brown (10YR 5/2) loam, dark brown (10YR 3/3) moist; weak medium prismatic structure parting to weak medium subangular blocky; slightly hard, friable; few pebbles; slightly alkaline; clear wavy boundary.
Bw2--12 to 16 inches; grayish brown (2.5Y 5/2) loam, dark grayish brown (2.5Y 4/2) moist; weak coarse and medium prismatic structure parting to weak medium subangular blocky; slightly hard, friable; few pebbles; slightly alkaline; clear wavy boundary. (Combined the Bw horizons is 6 to 14 inches thick.)
Bk1--16 to 30 inches; light yellowish brown (2.5Y 6/3) loam, light olive brown (2.5Y 5/3) moist; weak coarse prismatic structure parting to weak coarse subangular blocky; slightly hard, friable; few pebbles; many fine and medium soft masses and threads of calcium carbonate; violent effervescence; moderately alkaline; diffuse wavy boundary.
Bk2--30 to 48 inches; light yellowish brown (2.5Y 6/3) loam, light olive brown (2.5Y 5/3) moist; few fine distinct mottles of gray (2.5Y 6/1) redox depletions moist and few fine distinct olive yellow (2.5Y 6/6) redox concentrations moist; massive; slightly hard, friable; 5 percent pebbles (chalk rock); many medium and coarse masses of calcium carbonate; violent effervescence; moderately alkaline; diffuse wavy boundary. (Combined Bk horizons is 15 to 40 inches thick.)
C--48 to 60 inches; light yellowish brown (2.5Y 6/3) loam, light olive brown (2.5Y 5/4) moist; few fine distinct gray (2.5Y 6/l) redox depletions moist, few fine distinct olive yellow (2.5Y 6/6) and strong brown (7.5YR 5/6) redox concentrations moist; massive; slightly hard, friable; common pebbles; consolidated layers evident; few fine dark masses (Fe and Mn oxides); few fine threads of calcium carbonate; violent effervescence; moderately alkaline.
TYPE LOCATION: Davison County, South Dakota; 4 miles west and 4 miles north of Mitchell; 250 feet south and 1155 feet west of the northeast corner of sec. 3, T. 103 N., R. 61 W.
RANGE IN CHARACTERISTICS: Depth to calcium carbonates typically is 16 to 18 inches but ranges from 12 to 26 inches. Thickness of the mollic epipedon ranges from 8 to 20 inches and extends into the upper part of the Bw horizon in most pedons. The control section typically averages between 20 and 30 percent clay, but ranges to 34 percent in some pedons. Bulk density of the C horizon is between 1.50 to 1.80. Some pedons contain up to 10 percent by volume of rock fragments.
The A horizon has hue of 10YR, value of 3 or 4 and 2 or 3 moist, and chroma of 1 or 2. Typically it is loam, but some pedons are silt loam or fine sandy loam when mantled by a thin layer of sandy aeolian material. It is slightly acid or neutral.
The Bw horizon has hue of 10YR or 2.5Y, value of 4 or 5 and 2 to 4 moist, and chroma of 2 or 3. It is loam or clay loam. It ranges from slightly acid to slightly alkaline.
The Bk horizon has a hue of 10YR to 5Y, value of 5 to 7 and 4 to 6 moist, and chroma of 2 to 4. It is loam or clay loam. Masses of calcium carbonate are common or many. It is slightly or moderately alkaline. Crystals of gypsum are below depths of 40 inches in some pedons.
The C horizon has hue of 10YR to 5Y, value of 5 to 8 and 4 to 6 moist, and chroma of 2 to 4. It is loam or clay loam. It ranges from slightly to strongly alkaline. Some pedons have masses of gypsum.
COMPETING SERIES: These are the Hand and Josburg series. Hand soils have a lower bulk density in the C horizon. Josburg soils have carbonates below a depth of 26 inches.
GEOGRAPHIC SETTING: The Clarno soils are nearly level to moderately steep on glacial till plains. Slopes are plane to convex with slope gradients from 0 to 25 percent. The soil formed in friable, loam and clay loam glacial till. The mean annual air temperature is 45 to 52 degrees F, and the precipitation ranges from about 18 to 26 inches.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the competing Hand soils and the Betts, Bonilla, Crossplain, Davison, Dudley, Ethan, Houdek, Prosper, Stickney, and Tetonka soils. Hand soils are on similar landscapes as the Clarno soils. Betts soils do not have a mollic epipedon and are on ridgetops. Bonilla and Prosper soils have a mollic epipedon more than 20 inches thick and are in shallow ill-defined drainageways and flats. Crossplain soils have a fine textured argillic horizon and are wetter and in swales. Davison soils have a calcic horizon and are on slight rises and adjacent to swales and depressions. Dudley and Stickney soils have a natric horizon and are on nearly level landscape positions with microrelief. Ethan soils have carbonates within 10 inches of the surface and are on upper slopes. Houdek soils have an argillic horizon and are on similar landscapes to the Clarno soils. Tetonka soils are fine textured and wetter and are in depressions.
DRAINAGE AND PERMEABILITY: Well drained or moderately well drained. Surface runoff is low to high. Permeability is moderately slow.
USE AND VEGETATION: Most areas are cultivated and small grains, corn, and alfalfa are principal crops. Native vegetation is little bluestem, big bluestem, green needlegrass, needleandthread, western wheatgrass, sideoats grama, blue grama, and forbs.
DISTRIBUTION AND EXTENT: South-central and southeast South Dakota, east of the Missouri River and northeast Nebraska. The series is extensive.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: St. Paul, Minnesota
SERIES ESTABLISHED: Pierce County, Nebraska, 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 12 inches; cambic horizon - the zone from 12 to 16 inches (Bw2 horizon).
ADDITIONAL DATA: Lincoln Laboratory data 14247-14254 and 73469-73L490.