LOCATION BIGWINDER WY+NE SDEstablished Series
TAXONOMIC CLASS: Coarse-loamy, mixed, superactive, calcareous, mesic Aeric Fluvaquents
TYPICAL PEDON: Bigwinder fine sandy loam on an east facing stream terrace of one percent; utilized as rangeland. (Colors are for dry soil unless otherwise stated)
A--0 to 3 inches; light brownish gray (10YR 6/2) fine sandy loam, grayish brown (10YR 5/2) moist, common prominent strong brown (7.5YR 5/8) redox concentrations along root channels; moderate thick platy structure; slightly hard, very friable, nonsticky and nonplastic; strongly effervescent, calcium carbonate disseminated; slightly alkaline (pH 7.6); clear smooth boundary. (2 to 5 inches thick)
AC--3 to 8 inches; light gray (10YR 7/2) stratified sandy loam and loam, grayish brown (10YR 5/2) moist; common prominent strong brown (7.5YR 5/8) redox concentrations along root channels; moderate thick platy structure; hard, friable, slightly sticky and slightly plastic; strongly effervescent, calcium carbonate disseminated; moderately alkaline (pH 8.0); clear smooth boundary. (0 to 7 inches thick)
C1--8 to 17 inches; light gray (10YR 7/2) stratified loamy sand, loam, and sandy loam, pale brown (10YR 6/3) moist; common prominent strong brown (7.5YR 5/8) redox concentrations; faint organic stains in root channels; massive; slightly hard, very friable, nonsticky and nonplastic; violently effervescent, calcium carbonate disseminated; moderately alkaline (pH 8.0); clear wavy boundary.
C2--17 to 24 inches; light gray (10YR 7/2) stratified sandy loam and loamy sand, light brownish gray (10YR 6/2) moist; single grain; slightly hard, very friable, nonsticky and nonplastic; slightly effervescent, calcium carbonate disseminated; slightly alkaline (pH 7.4); gradual smooth boundary.
C3--24 to 60 inches; 60 percent light gray (10YR 7/2) and 40 percent reddish yellow (7.5YR 6/8) stratified loamy sand, sandy loam, and sand, light brownish gray (10YR 6/2) and reddish yellow (5YR 6/8) moist; massive; single grain; loose, nonsticky and nonplastic; slightly effervescent, calcium carbonate disseminated; slightly alkaline (pH 7.6).
TYPE LOCATION: Converse County, Wyoming; 1,250 feet north and 1,400 feet west of the southeast corner of Sec. 24, T. 39 N., R. 75 W. 43 degrees 20 minutes 00 seconds north latitude and 105 degrees 48 minutes 12 seconds west longitude.
RANGE IN CHARACTERISTICS: The mean annual soil temperature is 48 to 53 degrees F. The mean summer temperature is 63 to 73 degrees F. Organic matter content averages from 2 to 4 percent throughout the profile and decreases irregularly with depth. The particle size control section is highly stratified with thin to moderately thick lenses of sandy loam, loam, sand, very fine sandy loam and loamy sand but averages as fine or finer than loamy very fine sand. It is typically sandy loam or loam with less than 18 percent clay. EC ranges from 0 to 2 mmhos throughout. These soils have a seasonal high water at one to three feet from April through August in most years. Where mollic colors are present, they are not thick enough to be mollic epipedons.
The A horizon has hue of 10YR or 2.5Y, value of 5 through 7 dry, 3 through 5 moist and chroma of 1 or 2. It is fine sandy loam or very fine sandy loam. Reaction is neutral or slightly alkaline.
The AC horizon, when present, has the combined color properties of the A and C horizons. Reaction is slightly alkaline or moderately alkaline. The horizon consists of thin strata averaging sandy loam or loam.
The C horizon has hue of 10YR through 2.5Y, value of 5 through 7 dry, 3 through 6 moist, and chroma of 1 through 3. Textures are highly stratified with thin to moderately thick lenses of sand, loamy sand, loam, and sandy loams with an average texture of sandy loam. Reaction is slightly alkaline or moderately alkaline.
COMPETING SERIES: These are the Chesaning and Tweba series. Chesaning soils have a lithologic discontinuity at 25 to 40 inches and receive 30 to 37 inches of precipitation. Tweba soils have a seasonal high water table at 14 to 20 inches for a short period from February to June.
GEOGRAPHIC SETTING: The Bigwinder soils are on flood plains and low terraces. Slopes range from 0 to 3 percent. They formed in stratified deposits derived primarily from sandstone. Elevations range from 3600 to 5,500 feet. The mean annual precipitation is 10 to 14 inches with over half falling in March, April, May, and June. In South Dakota these soils are mapped at elevations as low as 2000 feet and at precipitation as high as 18 inches. These soils frequently flood for brief durations during spring months. A water table is present at a depth of one to three feet in the months of April through August. The mean annual air temperature averages 45 to 52 degrees F. The frost-free season is 105 to 130 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Clarkelen and Haverdad soils. The Clarkelen and Haverdad soils lack the wet properties and redoximorphic features. Also, Haverdad soils are fine-loamy. These soils typically occur somewhat higher on the flood plains and terraces.
DRAINAGE AND PERMEABILITY: Poorly drained; moderate permeability due to thin contrasting strata.
USE AND VEGETATION: Domestic livestock grazing and wildlife habitat. Native vegetation consists of Nebraska sedge, basin wildrye, slender wheatgrass, willow, and prairie cordgrass.
DISTRIBUTION AND EXTENT: East central Wyoming, western Nebraska, and South Dakota. The series is of minor extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Denver, Colorado
SERIES ESTABLISHED: Converse County, Wyoming; 1983.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
Ochric epipedon - 0 to 3 inches (A)
Aeric subgroup - The moist color of the C1 horizon meets the requirement for the Aeric subgroup
MLRR- G
SIRs'- WY0538, WY9094