LOCATION SHEAR UTEstablished Series
TAXONOMIC CLASS: Fine, mixed, active, calcareous, mesic Typic Torriorthents
TYPICAL PEDON: Shear silty clay rangeland (Colors are for dry soils unless otherwise noted.)
A--0 to 3 inches; light brownish gray (10YR 6/2) silty clay, grayish brown (2.5Y 5/2) moist; grayish brown (10YR 5/2) coatings on peds; weak medium blocky structure that parts to moderate very fine granular structure; the individual granular peds are about medium sand in size and give a mass consistence of loose; peds are hard, firm, sticky, plastic; few very fine roots; few very fine tubular pores; strongly calcareous; strongly alkaline (pH 9.0); clear smooth boundary. (2 to 3 inches thick)
Cl--3 to 20 inches; light brownish gray (10YR 6/2) silty clay, grayish brown (2.5Y 5/2) moist; grayish brown (10YR 5/2) coatings on peds; moderate fine angular blocky structure; the individual peds are about medium sand in size, and give a mass consistence of loose; peds are very hard, firm, sticky, plastic; few medium and fine roots; common very fine tubular pores; strongly calcareous; strongly alkaline (pH 8.8); gradual wavy boundary. (3 to 17 inches thick)
C2--20 to 53 inches; light brownish gray (10YR 6/2) silty clay, grayish brown (10YR 5/2) moist; grayish brown (10YR 5/2) coating on peds; strong very fine granular structure; the individual peds are about the size of medium sand particles and give a mass consistence of loose; individual peds are hard, firm, sticky, plastic; few coarse and fine roots; few fine random tubular pores; few salt and/or gypsum flecks in upper half of horizon; strongly calcareous; moderately alkaline (pH 8.0); abrupt smooth boundary. (7 to 33 inches thick)
C3--53 to 60 inches; light gray (10YR 7/2) silty clay loam, grayish brown (10YR 5/2) moist; common fine distinct yellowish brown (10YR 5/6) moist mottles; strong fine angular blocky structure; very hard, firm, sticky, plastic; few large and fine roots; common very fine random tubular pores; strongly calcareous; moderately alkaline (pH 8.0).
TYPE LOCATION: Millard County, Utah; 3 1/8 miles northwest of Hinckley; 415 feet south and 1,100 feet east of the NW corner of sec. 13, T.17S., R.8W.; lat. 39 degrees 20 minutes 38.63 seconds N. and long. 112 degrees 42 minutes 13.36 seconds W., NAD 83.
RANGE IN CHARACTERISTICS: The mean annual soil temperature ranges from 51 to 54 degrees F., and the mean summer soil temperature at a depth of 20 inches ranges from 69 inches to 72 inches F. These soils are dry in all parts of the moisture control section 75 to 85 percent of the time the soil temperature is about 41 degrees F.
Salinity and alkali affect ranges from moderate to strong and the calcium carbonate equivalent ranges from 15 to 40 percent. The organic matter remains above 35 percent to a depth of 50 inches. The 10 to 40 inch control section averages 40 to 60 percent clay.
The A horizon has hue of l0YR or 2.5Y, value of 4 or 5 moist, and chroma of 1 or 2. The very fine granular structure gives the appearance and loose consistence of medium sand. This horizon is dominantly silty clay, but ranges to sandy clay loam. It is strongly or very strongly alkaline.
The C horizon has hue of 10YR or 2.5Y, value of 6 dry above 40 inches and 6 or 7 dry below 40 inches, 4 or 5 moist, and chroma of 1 or 2. It is silty clay or silty clay loam. The C horizon is moderately or strongly alkaline. In some pedons distinct or prominent mottles occur below 50 inches. In some pedons, the C horizon contains salt and/or gypsum flecks that range from few to many.
COMPETING SERIES: These are the Navajo, Pocker, Tezuma, Winkleman, and Yuba series. Navajo soils have hue of 2.5YR or 5YR in the C horizon. None of these soils have the very fine granular structure that gives the general loose consistence of the mass. Yuba soils have salic horizons at depths of less than 30 inches.
GEOGRAPHIC SETTING: Shear soils formed on nearly level to sloping wind deposited dunes at depths of 4,550 to 4,600 feet. Slope gradients are 1 to 6 percent. The soils formed in eolian clays derived from igneous and sedimentary rocks. The climate is arid; mean annual temperature is 49 to 52 degrees F., mean summer temperature is 70 to 73 degrees F., and the frost-free period is 115 to 120 days. Average annual precipitation is 6 to 8 inches.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Abbott and Anco soils and the competing Yuba soils. Abbott soils have distinct or prominent mottles or low chroma within 20 inches of the surface. Anco soils average 27 to 35 percent clay in the control section.
DRAINAGE AND PERMEABILITY: Well drained; slow runoff; moderate permeability.
USE AND VEGETATION: Used only for rangeland. Native vegetation is greasewood, shadscale, seepweed, and halogeton.
DISTRIBUTION AND EXTENT: West central Utah. It is inextensive.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Phoenix, Arizona
SERIES ESTABLISHED: Millard County (Delta Area), Utah, 1970.