LOCATION RADEC UTEstablished Series
TAXONOMIC CLASS: Clayey-skeletal, smectitic, mesic Lithic Argixerolls
TYPICAL PEDON: Radec very cobbly loam, rangeland. (Colors are for dry soil unless otherwise noted.)
The soil surface is covered with 2 percent stones, 40 percent cobbles and 10 percent gravel.
A--0 to 2 inches; brown (10YR 5/3) very cobbly loam, dark brown (10YR 3/3) moist; weak medium subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; few medium, many fine and very fine roots; common medium, many fine and very fine pores; 10 percent gravel; neutral (pH 6.8); abrupt wavy boundary. (1 to 4 inches thick)
Bt1--2 to 7 inches; brown (7.5YR 5/2) very cobbly clay loam, dark brown (7.5YR 3/2) moist; moderate medium subangular blocky structure; hard, firm, sticky and plastic; few medium, common fine and very fine roots; few medium, many fine and very fine pores; common distinct clay films on faces of peds and lining pores; 40 percent cobbles; neutral (pH 6.8); clear smooth boundary. (3 to 8 inches thick)
Bt2--7 to 13 inches; reddish brown (5YR 5/4) very cobbly clay loam, reddish brown (5YR 4/4) moist; strong medium subangular blocky structure; hard, firm, sticky and plastic; common fine and very fine roots; few medium, many fine and very fine pores; many prominent clay films on faces of peds and lining pores; 45 percent cobbles; neutral (pH 7.0); abrupt wavy boundary. (4 to 8 inches thick)
R--13 inches; igneous bedrock.
TYPE LOCATION: Iron County, Utah, about 3.5 miles south of the junction of the Jackson Wash Road and the Pine Valley Road, about 1,150 feet north and 800 feet east of the southwest corner of section 27, T. 31 S., R. 16 W; Bible Spring Quadrangle; lat. 38 degrees 3 minutes 38 seconds N. and long. 113 degrees 38 minutes 5 seconds W.
RANGE IN CHARACTERISTICS:
Soil moisture - the soil moisture regime is xeric bordering on aridic. This soil is dry in all parts of the moisture control section for 60 to 90 days consectutive days in the summer.
Soil temperature - 47 to 52 degrees F.
Depth to bedrock - 10 to 16 inches.
Thickness of mollic epipedon - 7 to 10 inches or when the upper 7 inches of the soil is mixed. The mollic epipedon extends into upper part of argillic horizon.
Reaction - Neutral or slightly alkaline.
Control section - Clay content: 35 to 50 percent.
Rock fragments: 35 to 50 percent, dominantly gravel and cobbles.
A horizon - Hue: 10YR or 7.5YR.
Value: 4 or 5 dry, 2 or 3 moist.
Chroma: 2 or 3.
Texture: very gravelly loam or very cobbly loam.
Bt horizon - Hue: 7.5YR or 5YR.
Value: 4 or 5 dry, 3 or 4 moist.
Chroma: 2 or 3.
Texture: very cobbly clay loam or very cobbly clay.
COMPETING SERIES: These are the Camaspatch T(WA), Flatron (ID), Gwinly (OR), Laufer (WA), Longcreek (CA), Loomer (NV), Lorella (OR), Pioche (NV), Ruckles (OR), Vantage T(WA), and Waterbury (OR) series. Flatron, Ruckles and Waterbury soils have 50 to 60 percent clay in the particle-size control section. Gwinly and Laufer soils have a mollic epipedons that are thicker than 10 inches. Longcreek and Pioche soils have an aridic soil moisture regimes. Loomer soils have an aridic soil moisture regimes and 60 to 80 percent rock fragments in the paticle size control section. Vantage soils have an aridic soil moisture regimes and have silica accumulations in the argillic horizons. Camaspatch and Lorella soils do not allow 5YR colors in the Bt horizon and have slightly acid reactions and are dry for 90 or more consectutive days when the soil temperature is above 41 degrees F.
GEOGRAPHIC SETTING: Radec soils are on foothills and mountainsides. These soils formed in residuum and colluvium dominantly from igneous rocks. Slopes are 8 to 40 percent. Elevations are 5,600 to 7,100 feet. The mean annual precipitation is 12 to 14 inches. Mean annual air temperature is 45 to 50 degrees F., and the frost free period is 90 to 110 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Bodacious and Checkett soils. Bodacious soils lack argillic horizons. Checkett soils are loamy-sketetal.
DRAINAGE AND PERMEABILITY: Well drained; medium or rapid runoff; moderately slow permeability.
USE AND VEGETATION: Rangeland and wildlife habitat. Important plants are singleleaf pinyon and Utah juniper with an understory of black sagebrush, bluebunch wheatgrass and Indian ricegrass.
DISTRIBUTION AND EXTENT: Southwestern Utah. MLRA 28A. Radec soils are moderately extensive.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Phoenix, Arizona
SERIES ESTABLISHED: Iron County, Utah, Iron-Washington Area Soil Survey; 1997.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
Mollic epipedon - The zone from the soil surface to a depth of 7 inches (A and Bt1 horizons).
Argillic horizon - The zone from about 2 to 13 inches (Bt1 and Bt2 horizons).
Lithic contact - the boundary at 13 inches.
Classification is based on the "Keys to Soil Taxonomy, Eighth Edition, 1998".