LOCATION ELKCREEK IDEstablished Series
TAXONOMIC CLASS: Fine-loamy, mixed, superactive, frigid Ultic Argixerolls
TYPICAL PEDON: Elkcreek loam - rangeland. (Colors are for dry soil unless otherwise noted.)
A1--0 to 3 inches; dark grayish brown (10YR 4/2) loam, very dark brown (10YR 2/2) moist; weak thin platy structure parting to moderate fine granular; soft, very friable, slightly sticky and slightly plastic; many very fine and fine roots; many fine interstitial pores; 10 percent fine pebbles; slightly acid (pH 6.4); clear smooth boundary. (2 to 5 inches thick)
A2--3 to 8 inches; dark grayish brown (10YR 4/2) loam, very dark brown (10YR 2/2) moist; weak fine and medium subangular blocky structure; slightly hard, very friable, slightly sticky and slightly plastic; many very fine and fine, few medium and coarse roots; many fine tubular pores; neutral (pH 6.6); clear wavy boundary. (2 to 7 inches thick)
BA--8 to 12 inches; brown (10YR 4/3) loam, dark brown (10YR 3/3) moist; moderate medium subangular blocky structure; slightly hard, very friable, slightly sticky and slightly plastic; many very fine and fine roots; many fine tubular pores; neutral (pH 6.6); clear smooth boundary. (0 to 6 inches thick)
Bt1--12 to 22 inches; brown (10YR 5/3) clay loam, dark brown (10YR 3/3) broken, dark brown (10YR 4/3) rubbed, moist; moderate medium subangular blocky structure; hard, friable, sticky and plastic; few very fine, fine, and medium, many fine tubular pores; common thin clay films on all faces of peds; neutral (pH 6.6); gradual smooth boundary. (9 to 11 inches thick)
Bt2--22 to 31 inches; pale brown (10YR 6/3) clay loam, dark yellowish brown (10YR 4/4) moist; moderate medium subangular blocky structure; hard, friable, sticky and plastic; few medium and coarse roots; many fine and medium pores; common nearly continuous clay films on faces of peds and in pores; slightly acid (pH 6.4); clear smooth boundary. (8 to 12 inches thick)
R--31 inches; bedrock.
TYPE LOCATION: Camas County, Idaho; about 13 miles east and 10 miles south of Fairfield; 2,200 feet south, 300 feet east of the northwest corner of sec. 34, T. 2 S., R. 16 E.
RANGE IN CHARACTERISTICS:
Depth to bedrock - 20 to 40 inches
Average annual soil temperature - 42 to 47 degrees F.
Thickness of mollic epipedon - 10 to 16 inches
Base saturation - 50 to 75 percent in upper 75 cm
Reaction - moderately acid to neutral
A horizon
Hue - 7.5YR or 10YR
Value - 4 or 5 dry, 2 or 3 moist
Chroma - 1 through 3 dry or moist
Rock fragments - 0 to 15 percent
Bt horizons
Hue - 10YR or 7.5YR
Value - 5 or 6 dry, 3 through 5 moist
Chroma - 2 through 4 dry or moist
Texture - L, SCL, CL, ST-CL, ST-SICL
Clay content - 20 to 35 percent
Rock fragments - 0 to 35 percent
BC horizon (when present)
Value - 5 or 6 dry
Texture - L, CL, ST-L, ST-CL
Rock fragments - 5 to 20 percent
COMPETING SERIES: These are the Buffom, Carmack, Johnson, Mojo, Molyneux, Muldoon, Simonton, Skelter (T), Suloaf, and Trojan. Buffom, Carmack, Johnson, Molyneux, Muldoon, Simonton, Skelter, Suloaf, and Trojan soils are more than 40 inches deep to bedrock. Mojo soils have 35 to 50 percent rock fragments in the lower part of the argillic horizon.
GEOGRAPHIC SETTING: Elkcreek soils are on foothills and mountainsides and have slopes of 0 to 60 percent. Elevation is 4,500 to 6,500 feet. The soils formed in loess and residuum and alluvium derived from igneous rock. The soils formed in a continental climate having cool dry summers and cold wet winters. Average annual precipitation is 12 to 18 inches and the average annual air temperature is 40 to 45 degrees F. The frost-free period is 60 to 100 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Gaib, Mulshoe, Peevywell, Polecreek, Rands, and the Simonton soils. Gaib and Polecreek soils are less than 20 inches deep. Mulshoe soils have greater than 35 percent rock fragments in the control section. Peevywell soils are moderately deep to a duripan. Rands soils have more than 35 percent clay in the control section and are very deep. Simonton soils are very deep. Peevywell, Rands, and Simonton soils occur on fan terraces. Gaib, Mulshoe, and Polecreek occur on the same landscape as Elkcreek.
DRAINAGE AND PERMEABILITY: Well drained, slow to very rapid runoff, moderately slow permeability.
USE AND VEGETATION: Used mainly for rangeland. Vegetation in the potential natural plant community is mountain big sagebrush, bluebunch wheatgrass, and Idaho fescue.
DISTRIBUTION AND EXTENT: South-central Idaho. The series is of moderate extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Portland, Oregon
SERIES ESTABLISHED: Camas County, Idaho, 1977.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
Mollic epipedon - occurs from the soil surface to approximately 12 inches (A1, A2, and Bw horizons)
Argillic horizon - in the zone from approximately 12 to 31 inches (Bt1 and Bt2 horizons)
Particle-size control section - the zone from approximately 12 to 31 inches (argillic horizon)
Base saturation - in 50 to 75 percent in the upper 75 cm