LOCATION DRAX IDEstablished Series
TAXONOMIC CLASS: Fine-loamy, mixed, superactive, mesic Fluventic Haploxerolls
TYPICAL PEDON: Drax silt loam, cultivated. (Colors are for dry soil unless otherwise noted.)
Ap--0 to 8 inches; grayish brown (10YR 5/2) silt loam, very dark grayish brown (10YR 3/2) moist; weak medium subangular blocky structure that parts to weak fine granular; slightly hard, friable, sticky and plastic; many fine roots; common fine pores; moderately alkaline (pH 8.4); clear smooth boundary. (6 to 10 inches thick)
A12--8 to 14 inches; grayish brown (10YR 5/2) silt loam, very dark grayish brown (10YR 3/2) moist; weak medium subangular blocky structure that parts to weak fine granular; slightly hard, friable, slightly sticky and plastic; many fine and very fine roots; common fine pores; moderately alkaline (pH 8.4); clear smooth boundary. (4 to 8 inches thick)
C1--14 to 21 inches; light brownish gray (10YR 6/2) silt loam, dark grayish brown (10YR 4/2) moist; weak medium subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; common very fine roots; many very fine pores; moderately alkaline (pH 8.3); clear smooth boundary. (5 to 9 inches thick)
C2--21 to 28 inches; light brownish gray (10YR 6/2) silt loam, dark grayish brown (10YR 4/2) moist; weak medium subangular blocky structure; soft, very friable, slightly sticky and slightly plastic; few very fine roots; common very fine pores; slightly calcareous; moderately alkaline (pH 8.4); clear smooth boundary. (5 to 9 inches thick)
IIA1b--28 to 38 inches; dark gray (10YR 4/1) silty clay loam, very dark gray (10YR 3/1) moist; few fine faint brown mottles; moderate medium and fine subangular blocky structure; slightly hard, friable, sticky and plastic; few very fine roots; common fine pores; moderately alkaline (pH 8.2); abrupt wavy boundary. (9 to 10 inches thick)
IIC3--38 to 48 inches; light brownish gray (10YR 6/2) silt loam, dark grayish brown (10YR 4/2) moist; weak medium subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; few very fine roots; many very fine pores; slightly calcareous; moderately alkaline (pH 8.2); abrupt wavy boundary. (9 to 10 inches thick)
IIC4--48 to 55 inches; light brownish gray (10YR 6/2) silt loam, dark grayish brown (10YR 4/2) moist; massive; slightly hard, friable, slightly sticky and slightly plastic; common very fine pores; slightly calcareous; moderately alkaline (pH 8.4); diffuse smooth boundary. (3 to 12 inches thick)
IIC5--55 to 72 inches; light brownish gray (10YR 6/2) silt loam, grayish brown (10YR 5/2) moist; few fine faint brown mottles; massive; slightly hard, friable, slightly sticky and slightly plastic; many very fine pores; moderately alkaline (pH 8.3).
TYPE LOCATION: Cassia County, Idaho; about 5 miles south of Burley; 800 feet south and 1,950 feet west of the NE corner of sec. 24, T. 11 S., R. 22 E.
RANGE IN CHARACTERISTICS: The mean annual soil temperature ranges from 49 degrees to 53 degrees F. Faint mottles commonly occur at depths below 28 inches and above 40 inches. In some pedons th soil profile contains 5 to 10 percent fine gravel.
The A horizon has value of 2 or 3 moist, 4 or 5 dry, and chroma of 2 or 3. Organic matter is about 3 to 5 percent in the A horizon, and decreases irregularly with increasing depth. Reaction ranges from neutral to mildly alkaline.
The C horizon has value of 6 or 7 dry, 4 or 5 moist, and chroma of 2 or 3. Stratification occurs in the C horizon, with buried A horizons common. Calcium carbonate content is variable, ranging from a trace to moderately calcareous, and commonly occurs below depth of 20 inches. Reaction ranges from mildly to moderately alkaline.
COMPETING SERIES: This is the Ebbs series. Ebbs soils are well drained and are calcareous on the surface.
GEOGRAPHIC SETTING: Drax soils are on low terraces and have slopes of 0 to 3 percent. They formed in material weathered from mixed alluvium derived mainly from acid igneous rocks and loess. Elevations are 2,500 to 4,800 feet. The climate is semiarid. Mean annual precipitation is 8 to 11 inches. Mean annual temperature is 47 degrees to 51 degrees F. Frost-free season is about 110 to 160 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Beetville and Goose Creek soils. Beetville soils are coarse-loamy. Goose Creek soils have a mollic epipedon more than 20 inches thick.
DRAINAGE AND PERMEABILITY: Moderately well drained; slow runoff; moderately slow permeability.
USE AND VEGETATION: Used mainly for irrigated cropland. Principal crops are beans, sugar beets and grain. Where the soils are not cultivated, vegetation is basin wildrye, big sagebrush, bluebunch wheatgrass, and associated forbs.
DISTRIBUTION AND EXTENT: Cassia County, Idaho. The series is inextensive.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Portland, Oregon