LOCATION SEVIER UTEstablished Series
TAXONOMIC CLASS: Fine, mixed, superactive Ustic Argicryolls
TYPICAL PEDON: Sevier very fine sandy loam--rangeland (Colors are for air-dry soil unless otherwise stated).
A1--0 to 4 inches; brown (10YR 5/3) very fine sandy loam, dark brown (10YR 3/3) moist; crushed; weak very thin platy structure parting to weak fine granular; slightly hard, very friable, slightly sticky and slightly plastic; common very fine and fine roots; common fine pores; neutral (pH 7.0); clear smooth boundary. (2 to 4 inches thick)
A2--4 to 9 inches; brown (10YR 5/3) clay loam, dark brown (10YR 3/3) moist; crushed; weak medium subangular blocky structure parting to moderate fine granular; slightly hard, friable, slightly sticky and slightly plastic; few very fine, fine and medium roots; few very fine pores; neutral (pH 7.0); clear smooth boundary. (3 to 6 inches thick)
Bt--9 to 15 inches; pale brown (10YR 6/3) clay loam, dark brown (10YR 3/3) moist; crushed; moderate medium angular blocky structure parting to moderate fine angular blocky; extremely hard, very firm, sticky and plastic; few very fine roots; common very fine pores; common moderately thick clay films on faces of peds; neutral (pH 7.1); clear smooth boundary. (4 to 10 inches thick)
C--15 to 24 inches; light gray and light yellowish brown (N 7/ and 2.5Y 6/4) silty clay, light olive brown (2.5Y 5/4) moist; crushed; strong medium platy structure that parts to strong coarse angular blocky; extremely hard, very firm, sticky and plastic; few very fine roots; many very fine pores; neutral (pH 7.2).
Cr--24 inches; weathered shale.
TYPE LOCATION: Kane County, Utah; Podunk Creek; NW1/4 SW1/4 sec. 13, T. 38 S., R. 4 1/2 W.
RANGE IN CHARACTERISTICS: The mollic epipedon is 7 to 10 inches thick. The soil depth to soft bedrock (paralithic contact) ranges from 20 to 40 inches. Rock fragments average less than 35 percent in the solum. The mean annual soil temperature is about 38 to 44 degrees F. and the mean summer soil temperature at the paralithic contact is about 54 to 58 degrees F. The A horizon has hue of 7.5YR or 10YR, value of 4 or 5 dry, and chroma of 3 or 4 dry. It is calcareous.
The Bt horizon has hue of 7.5YR to 2.5Y, value of 5 to 7 dry, 3 to 5 moist, and chroma of 3 to 6. It ranges from sandy clay loam and clay loam to cobbly and gravelly clay loam; clay content (estimated) averages 35 to 42 percent. The Bt horizons are noncalcareous to strongly calcareous.
The C horizon has hue of 10YR or 2.5Y, value of 4 to 7 dry, 4 or 5 moist, and chroma of 1 to 4.
COMPETING SERIES: These are the Bridger, Echard, and Rattler series. All are deeper than 40 inches to bedrock.
GEOGRAPHIC SETTING: The Sevier soils are on moderately sloping to moderately steep benches and colluvial toeslopes above and adjacent to drainageways. They formed in colluvium and residuum from shale and thin-bedded sandstones. Elevations range from 7,800 to 8,500 feet. Slope gradients are 5 to 25 percent. The average annual precipitation is 16 to 20 inches and the freeze-free period ranges from 60 to 70 days. The mean annual temperature is 36 to 42 degrees F. and the average summer temperature is 54 to 58 degrees F.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Hatch, Pahrea, Sielo, Skutum, and Swapps soils. Hatch, Sielo and Swapps soils lack mollic epipedons. Pahreah soils have more than 35 percent rock fragments and less than 35 percent clay in the control section. Skutum soils are deeper than 40 inches.
DRAINAGE AND PERMEABILITY: Moderately well drained; rapid runoff; very slow permeability.
USE AND VEGETATION: Nearly all areas are used for rangeland and wildlife habitat. The native vegetation is big sagebrush and rabbitbrush, peavine, and grasses.
DISTRIBUTION AND EXTENT: These are in the south-central part of Utah. They are not extensive.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Bozeman, Montana
SERIES ESTABLISHED: Kane County (Panguitch Soil Survey Area), Utah, 1984.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
Mollic epipedon - the zone from the surface of the soil to 9 inches. (A1, A2 horizons)
Argillic horizon - the zone from 9 to 15 inches. (Bt horizon)