LOCATION UCROSS WYEstablished Series
TAXONOMIC CLASS: Fine-loamy, mixed, superactive, calcareous, mesic Aridic Ustorthents
TYPICAL PEDON: Ucross loam - on a northeast facing slope of 5 percent, utilized rangeland. (Colors are for dry soil unless otherwise stated)
A--0 to 5 inches; brown (10YR 5/3) loam, brown (10YR 4/3) moist; moderate fine and medium granular structure; slightly hard, firm, nonsticky and nonplastic; many very fine and fine roots throughout and common medium throughout; many fine pores; slightly effervescent; moderately alkaline; clear smooth boundary. (1 to 7 inches thick)
Bk1--5 to 17 inches; pale brown (10YR 6/3) clay loam, brown (10YR 5/3) moist; moderate fine and medium subangular blocky structure; slightly hard, firm, slightly sticky and slightly plastic; many very fine and fine roots throughout and common medium throughout; many fine pores; common fine irregular light gray (10YR 7/2) carbonate threads throughout; strongly effervescent; moderately alkaline; clear smooth boundary.
Bk2--17 to 31 inches; light yellowish brown (10YR 6/4) clay loam, yellowish brown (10YR 5/4) moist; moderate fine and medium subangular blocky structure; slightly hard, firm, slightly sticky and slightly plastic; many very fine and fine roots throughout; common fine pores; common fine irregular light gray (10YR 7/2) carbonate threads throughout; strongly effervescent; strongly alkaline; abrupt wavy boundary. (Combined Bk horizons 0 to 33 inches thick)
Cr--31 to 60 inches; light yellowish brown (10YR 6/4) soft calcareous shale interbedded with mudstones and sandstone.
TYPE LOCATION: Campbell County, Wyoming; about 50 feet south and 25 feet west of the northeast corner Section 9 T 55 N, R 74 W.; USGS Reservoir Creek WY topographic quadrangle; lat. 44 degrees 45 minutes 58 seconds N. and long. 105 degrees 45 minutes 34 seconds W.
RANGE IN CHARACTERISTICS: Depth to bedrock is 20 to 40 inches. The soils are typically effervescent to the surface but may be noneffervescent in the upper 6 inches of some pedons. The particle-size control section averages 20 to 35 percent clay and 15 to 35 percent fine and coarser sand. It has 0 to 15 percent angular channers. The moisture control section is usually moist in some or all parts in March through June. The average annual soil temperature is 47 to 50 degrees F.
The A horizon has hue of 10YR or 2.5Y, value of 5 to 7 dry and 4 or 5 moist, and chroma of 2 to 4. It is loam, clay loam or silt loam. It is neutral to moderately alkaline.
An AC or Bw horizon is present in some pedons. They have properties similar to both the A horizon and C horizon. The Bw horizon is not thick enough to be cambic.
The Bk horizon (and C horizon, when present) has hue of 7.5YR, 10YR or 2.5Y, value of 5 to 7 dry and 4 to 6 moist, and chroma of 2 to 4. It is loam, silty clay loam or clay loam. It has less than 15 percent calcium carbonate equivalent. It is slightly alkaline to strongly alkaline.
The Cr horizon consists of sandy and silty shale, or interbedded sandstone and shale. The bedrock may be effervescent throughout, inconsistently effervescent in various layers, or noneffervescent. Thin layers of lignite occur in some pedons at various depths.
COMPETING SERIES: These are the Iwait and Kimst series. These soils are very deep.
GEOGRAPHIC SETTING: Ucross soils are on fan remnants, hills and ridges. They formed in residuum or alluvium over residuum derived from mixed sedimentary sources. Slopes are 0 to 50 percent. Elevations are 3,500 to 5,200 feet. The mean annual precipitation ranges from 15 to 17 inches, half of which falls as rain or snow from March through June. The mean annual air temperature ranges from 44 to 50 degrees F. The frost-free season is about 105 to 130 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the competing Iwait soils and the Deekay, Oldwolf, Fairburn and Ziggy soils. Deekay and Oldwolf soils have argillic horizons. Fairburn soils are shallow. Ziggy soils have cambic horizons.
DRAINAGE AND PERMEABILITY: Well drained; low to medium runoff; moderate permeability.
USE AND VEGETATION: These soils are utilized primarily as rangeland, hayland and pasture, nonirrigated cropland, and wildlife habitat. The native vegetation is mainly needleandthread, western wheatgrass, blue grama, and green needlegrass. Winter wheat, oats, and alfalfa are the principle cultivated crops.
DISTRIBUTION AND EXTENT: Ucross soils occur in the Powder River basin of north-central and northeastern Wyoming. The series is of limited extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Denver, Colorado
SERIES ESTABLISHED: Campbell County, Wyoming, Southern Part; 1995
REMARKS: Diagnostic horizons and features recognized in this pedon are: Ochric epipedon - 0 to 5 inches (A); Paralithic contact - 31 inches (top of the Cr horizon)
SIR- WY1367
LRR- G