LOCATION HILIGHT WYEstablished Series
TAXONOMIC CLASS: Clayey, smectitic, nonacid, mesic, shallow Ustic Torriorthents
TYPICAL PEDON: Hilight clay loam-on a 6 percent slope with a southerly aspect under native vegetation. (Colors are for dry soil unless otherwise stated)
A--0 to 4 inches; light brownish gray (10YR 6/2) clay loam, dark grayish brown (10YR 4/2) moist; moderate medium subangular blocky structure; very hard, firm, moderately sticky and moderately plastic; many fine roots; neutral; clear smooth boundary. (2 to 6 inches thick)
C--4 to 16 inches; grayish brown (10YR 5/2) clay, dark grayish brown (10YR 4/2) moist; weak coarse subangular blocky structure with over 60 percent plate-like rock structure; very hard, firm, moderately sticky and moderately plastic; few fine roots; neutral, abrupt wavy boundary.
Cr--16 inches; dark colored, platy, noncalcareous shale.
TYPE LOCATION: Weston County, Wyoming; 9 miles northeast of Upton, Wyoming; 1,980 feet west and 660 feet south of the center of sec. 2, T. 48 N., R. 64 W. 44 degrees 10 minutes 18 seconds north latitude and 104 degrees 30 minutes 53 seconds west longitude.
RANGE IN CHARACTERISTICS: Base saturation ranges from 60 to 100 percent but typically is more than 90 percent. Depth to the paralithic contact ranges from 6 to 20 inches. The mean annual soil temperature is 47 to 52 degrees F. The control section is usually heavy clay loam, silty clay loam, silty clay or clay and averages 35 to 55 percent clay. Rock fragments range from 0 to 15 percent by volume, are generally less than 5 percent, and break down with pretreatment. Gypsum may be present in some pedons in horizons immediately above the shale.
The A horizon has hue of 2.5Y, 10YR or 7.5YR, value of 4 to 7 dry, 3 to 6 moist, and chroma of 1 to 4. It ranges from slightly acid to moderately alkaline.
The C horizon has hue of 2.5Y, 10YR or 7.5YR, value of 5 to 7 dry, 3 to 6 moist, and chroma of 1 to 4. Reaction is slightly acid to moderately alkaline.
COMPETING SERIES: These are the Payan series. Payan soils are drier during the period of May 15 to July 15.
GEOGRAPHIC SETTING: The Hilight soils are on hills, breaks and ridges where shale bedrock occurs close to the surface. Slope gradients range from 0 to 60 percent. They formed in thin parent materials weathered from noncalcareous shale. Elevation ranges from 3,500 to 6,500 feet. At the type location the average annual precipitation is 12 inches but ranges from 10 to 14 inches with peak periods of precipitation occurring in April, May, and June. The mean annual temperature is 46 to 48 degrees F. The frost-free season is about 105 to 130 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Twotop, Wags and Winler soils. Twotop and Winler soils have cambic horizons and lack bedrock above 20 inches. Wags soils are moderately deep.
DRAINAGE AND PERMEABILITY: Well drained; rapid runoff; slow permeability.
USE AND VEGETATION: These soils are used principally as rangeland. Native vegetation is mainly rhizomatous wheatgrass, green needlegrass, and blue grama.
DISTRIBUTION AND EXTENT: Eastern and central Wyoming. The series is of moderate extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Denver, Colorado
SERIES ESTABLISHED: Weston County, Wyoming; 1983.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
Ochric epipedon - 0 to 4 inches (A)
Paralithic contact - 16 inches (Cr)
LRR- G
SIR- WY1142