LOCATION CEDAR BUTTE SDEstablished Series
TAXONOMIC CLASS: Fine, smectitic, mesic Torrertic Natrustalfs
TYPICAL PEDON: Cedar Butte silt loam - on a nearly level area less than 2 percent slope in native grass. When described the soil was dry throughout. (Colors are for dry soil unless otherwise stated)
E1--0 to 4 inches; light brownish gray (10YR 6/2) silt loam, very dark grayish brown (10YR 3/2) moist; weak very fine platy and weak fine granular structure; slightly hard, very friable; slightly alkaline; abrupt smooth boundary.
E2--4 to 6 inches; light brownish gray (10YR 6/2) silt loam, very dark grayish brown (10YR 3/2) moist; weak very fine platy structure; slightly hard, very friable; vesicular pores; slightly alkaline; abrupt wavy boundary. (Combined E horizons 4 to 8 inches thick)
Btn1--6 to 8 inches; dark grayish brown (10YR 4/2) clay, very dark brown (10YR 2/2) moist; strong fine columnar structures; extremely hard, extremely firm, very sticky, very plastic; light gray (10YR 7/2) silt loam coatings on tops of columns, dark grayish brown (10YR 4/2) moist; slightly alkaline; abrupt smooth boundary. (2 to 4 inches thick)
Btn2--8 to 12 inches; dark grayish brown (10YR 4/2) clay, very dark grayish brown (10YR 3/2) crushing to dark grayish brown (10YR 4/2) moist; moderate medium prismatic structure parting to weak medium blocky structure; extremely hard, extremely firm, very sticky, very plastic; shiny film on faces of peds; moderately alkaline; clear smooth boundary. (4 to 12 inches thick)
Btkn--12 to 17 inches; light brownish gray (10YR 6/2) and grayish brown (10YR 5/2) clay, grayish brown (10YR 5/2) moist; weak coarse prismatic structure parting to weak medium blocky structure; very hard, very firm, slightly sticky and plastic; shiny film on faces of peds; few medium accumulations of carbonate; strong effervescence; strongly alkaline; gradual smooth boundary. (0 to 17 inches thick)
Bk--17 to 42 inches; light brownish gray (10YR 6/2) silty clay, grayish brown (10YR 5/2) moist; weak coarse prismatic structure; very hard, very firm, sticky, plastic; few fine accumulations of carbonate; strong effervescence; strongly alkaline; clear smooth boundary. (10 to 35 inches thick)
2C--42 to 60 inches; pale brown (10YR 6/3) gravelly sand, dark grayish brown (10YR 4/2) moist; single grained; loose both dry and moist; many pebbles coated on underside with carbonate; slight effervescence; abrupt wavy boundary. (0 to 30 inches thick)
3Cr--60 to 65 inches; green, olive and red bedded shale.
TYPE LOCATION: Mellette County, South Dakota; about 3 miles west and 2 miles north of Cedar Butte; 2080 feet south and 1320 feet east of the northwest corner of sec. 24, T. 42 N., R. 32 W.
RANGE IN CHARACTERISTICS: Depth to carbonates ranges from 10 to 24 inches. Accumulations of salt or gypsum typically are below 16 inches. SAR and ESP range from 13 to 30.
The E horizon has hue of 10YR or 2.5Y, value of 5 to 7 and 3 to 5 moist, and chroma of 2 or 3. It typically is silt loam, but some pedons are loam or very fine sandy loam. It is slightly acid to slightly alkaline. Some pedons have an A horizon.
The Btn1 horizon has hue of 10YR or 2.5Y, value of 3 to 5 and 2 or 3 moist, and chroma of 1 to 3. It is clay, silty clay or silty clay loam and is neutral to moderately alkaline. It has light gray coatings or a silt loam cap less than 1 inch thick on top of columns in some pedons.
The Btn2 horizon has hue of 10YR or 2.5Y, value of 4 to 6 and 3 to 5 moist, and chroma of 1 to 3. It is clay or silty clay and is slightly alkaline to strongly alkaline.
The Bk and Btkn horizons have hue of 10YR, 2.5Y or 5Y, value of 4 to 6 and 4 or 5 moist, and chroma of 1 to 3. They are clay, silty clay or silty clay loam. They have few to many fine or very fine accumulations of carbonates. They are moderately alkaline or strongly alkaline.
Some pedons have C horizons which have color and texture of the Bk horizons.
The 2C horizon when present occurs below a depth of 40 inches. It is multicolored shale and/or gravelly sand. It ranges from slightly alkaline to strongly alkaline.
COMPETING SERIES: These are the Arvada, Hisle, Wanblee and Winnett soils. Arvada soils typically have salt accumulation above depths of 16 inches. Hisle, Wanblee, and Winnett soils have paralithic contact within depths of 20 to 40 inches.
GEOGRAPHIC SETTING: Cedar Butte soils are on nearly level to gently sloping Uplands, alluvial fans, fan remnants, terraces and hills with gradients of 0 to 6 percent slope. Soils formed in clayey sediments or clayey residuum. Mean annual air temperature is about 45 to 48 degrees F, and mean annual precipitation from about 12 to 18 inches.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the competing Hisle soils and the Larvie, Metre, and Orella soils. Hisle soils are on similar positions as the Cedar Butte soils. Larvie and Metre soils do not have a natric horizon and are underlain by shale between depths of 20 and 40 inches. They are on slightly higher slopes. Orella soils have steeper slopes, are shallow to shale, and have high sodium content.
DRAINAGE AND PERMEABILITY: Well drained. Surface runoff is low to high depending on slope. Permeability is slow in the upper part and rapid in the underlying material.
USE AND VEGETATION: Mostly range; native vegetation is western wheatgrass, blue grama, green needlegrass and forbs.
DISTRIBUTION AND EXTENT: Small extent, mostly in southwestern South Dakota
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Denver, Colorado
SERIES ESTABLISHED: Mellette County, South Dakota, 1971.
REMARKS: Diagnostic horizons and features recognized in this pedon are: Ochric epipedon - the zone from the surface of the soil to a depth of 6 inches (E1 and E2 horizons); natric horizon - the zone from a depth of about 6 to 12 inches (Btn1 and Btn2 horizons).
The series may be in the Torrertic subgroup.