LOCATION CHITTUM WY+CO UTEstablished Series
TAXONOMIC CLASS: Loamy, mixed, superactive Lithic Argicryolls
TYPICAL PEDON: Chittum gravelly loam-rangeland. (Colors are for dry soil unless otherwise stated.)
A--0 to 5 inches; brown (7.5YR 4/4) gravelly loam, dark brown (7.5YR 3/2) moist; moderate fine granular structure; soft, very friable, many very fine and fine roots; 15 percent gravel; slightly acid (pH 6.4); abrupt smooth boundary. (3 to 7 inches thick)
Bt1--5 to 11 inches; reddish brown (5YR 4/3) gravelly loam, dark reddish brown (5YR 3/2) moist; moderate medium prismatic structure parting to moderate fine subangular blocky; soft, very friable, slightly sticky and slightly plastic; many very fine and fine roots; continuous faint clay films on all faces of peds; 15 percent gravel; slightly acid (pH 6.2); clear wavy boundary. (4 to 8 inches thick)
Bt2--11 to 17 inches; yellowish red (5YR 5/6) gravel clay loam, reddish brown (5YR 4/4) moist; moderate medium prismatic structure that parts to moderate very fine subangular blocky; slightly hard, very friable, moderately sticky and slightly plastic; common very fine and fine roots; continuous faint clay films on vertical faces of peds and prominent clay films in pores and root channels; 15 percent gravel; moderately acid (pH 6.0); abrupt wavy boundary. (0 to 8 inches thick)
2R--17 inches; fractured sandstone; fractures more than 4 inches apart.
TYPE LOCATION: Washakie County, Wyoming; 30 feet SW of 1/4 corner of sec. 20, T. 42 N., R. 86 W.
RANGE IN CHARACTERISTICS: Depth to bedrock is 8 to 20 inches. The mean annual soil temperature ranges from 42 to 45 degrees F. Rock fragments, mainly less than 3 inches in diameter, range from 5 to 35 percent throughout.
The A horizon has hue of 2.5YR through 10YR, value of 3 through 5 dry, 2 or 3 moist, and chroma of 2 through 4. Reaction is moderately acid, slightly acid, or neutral.
The Bt horizon has hue of 5YR or 2.5YR. It is loam, clay loam, or sandy clay loam with 18 to 35 percent clay and may be modified by rock fragments. Sand content ranges from 20 to 52 percent with less than 35 percent fine sand or coarser. Reaction is moderately acid, slightly acid, or neutral.
COMPETING SERIES: These are the Carbol, Gilispie, Katseanes, and Mahogee series. Carbol soils have Bt2 horizons with more than 35 percent fine or coarser sand. Gilispie soils have Bt2 horizons with hue of 2.5Y through 7.5YR. Katseanes, and Mahogee soils have a hue of 10YR in the argillic horizon.
GEOGRAPHIC SETTING: Chittum soils are on upland backslopes and footslopes. Slopes are 2 to 45 percent. The soils formed in material weathered from hard sandstone. Elevation is 6,800 to 9.500 feet. The mean annual precipitation ranges from 15 to 19 inches. The mean annual temperature ranges from 33 to 43 degrees F. The frost-free season is estimated at less than 90 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Greenman, Irigul, Starley, Splitro, and Woosley soils. Greenman soils have bedrock at depths of 20 to 40 inches and are coarse-loamy. Irigul and Starley soils do not have an argillic horizon and are loamy-skeletal. Splitro soils have less than 18 percent clay in the control section. Woosley soils have bedrock at depths of 20 to 40 inches.
DRAINAGE AND PERMEABILITY: Well drained; slow to rapid runoff; moderate permeability.
USE AND VEGETATION: These soils are used for rangeland and wildlife habitat. Native vegetation is Idaho fescue, slender wheatgrass, oat grass, Canby bluegrass, upland sedge, and sandwort.
DISTRIBUTION AND EXTENT: In the Big Horn Mountains and foothills of north-central and west-central Wyoming. The series is of moderate extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Bozeman, Montana
SERIES ESTABLISHED: Washakie County, Wyoming; 1976.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
Mollic epipedon - The zone from the soil surface to 11 inches (A and Bt1 horizons).
Argillic horizon - The zone from 5 to 17 inches (Bt1 and Bt2 horizons).
Lithic contact - The boundary at 17 inches to underlying hard, unweathered bedrock (R layer).
Particle-size control section - The zone from 5 to 17 inches (Bt1 and Bt2 horizons).