LOCATION SLUKA IDEstablished Series
TAXONOMIC CLASS: Coarse-silty, mixed, superactive, mesic Xeric Haplodurids
TYPICAL PEDON: Sluka silt loam--on a southwest facing slope of 7 percent under rangeland vegetation at 3,480 feet elevation. (Colors are for dry soil unless otherwise stated.) When described on November 16, 1983, the soil profile was dry.
A--0 to 4 inches; pale brown (10YR 6/3) silt loam, brown (10YR 4/3) moist; moderate medium platy structure; soft, very friable, slightly sticky and slightly plastic; many very fine, fine, and medium roots; many very fine and fine tubular pores; slightly effervescent (5 percent calcium carbonate); slightly alkaline (pH 7.8); gradual wavy boundary. (3 to 6 inches thick)
Bkq1--4 to 11 inches; pale brown (10YR 6/3) silt loam, brown (10YR 5/3) moist; weak medium subangular blocky structure; slightly hard, friable; nonsticky and nonplastic; many very fine, fine, and medium roots; many very fine and fine tubular pores; (20 percent durinodes); strongly effervescent (10 percent calcium carbonate); moderately alkaline (pH 8.0); clear smooth boundary. (6 to 26 inches thick)
Bkq2--11 to 21 inches; very pale brown (10YR 7/3) silt loam, pale brown (10YR 6/3) moist; weak medium subangular blocky structure; very hard, very firm; nonsticky and nonplastic; common very fine, fine, and medium roots; common very fine tubular pores; (40 percent durinodes); strongly effervescent (16 percent calcium carbonate); moderately alkaline (pH 8.0); abrupt smooth boundary. (6 to 20 inches thick)
Bkqm--21 to 37 inches; indurated duripan with continuous silica and calcium carbonate cemented 1/16 inch laminar cap over pale brown (10YR 6/3) loam, brown (10YR 5/3) moist; massive; very hard, very firm, and brittle; root matting on surface of laminar cap with few very fine roots along fracture planes; strongly effervescent (13 percent calcium carbonate) moderately alkaline (pH 8.0); abrupt smooth boundary. (10 to 40 inches thick)
2Bk--37 to 51 inches; pale brown (10YR 6/3) very fine sandy loam, brown (10YR 5/3) moist; massive; slightly hard, friable; nonsticky and nonplastic; strongly effervescent (13 percent calcium carbonate); moderately alkaline (pH 8.4); abrupt smooth boundary. (0 to 33 inches thick)
2Bkqm--51 to 61 inches; indurated duripan with continuous silica and calcium carbonate cemented 1/4 inch laminar cap over pale brown (10YR 6/3) loam, brown (10YR 4/3) moist; massive; very hard, very firm, and brittle; strongly effervescent 11 percent calcium carbonate); moderately alkaline (pH 8.4).
TYPE LOCATION: Twin Falls County, Idaho, about 16 miles northwest of Buhl, Idaho; in the southwest 1/4, southwest 1/4, southeast 1/4 of section 15 T. 8 S., R. 12 E.
RANGE IN CHARACTERISTICS:
Soil temperature - 51 to 53 degrees F.
Depth to carbonates - 0 to 12 inches
Depth to duripan - 20 to 40 inches
Depth to bedrock - greater than 60 inches
Control section; clay - 12 to 18 percent
Depth to calcic horizon - 10 to 30 inches
A horizon
Value - 5 or 6 dry, 3 or 4 moist
Chroma - 2 or 3 dry or moist
Gravel - 0 to 10 percent
Effervescence - none through strong
Reaction - neutral through slightly alkaline
Calcium carbonate - 0 to 10 percent
Bkq horizons
Value - 6 through 8 dry, 3 through 6
Chroma - 2 or 3 dry or moist
Texture - SIL or VFSL
Clay - 12 to 18 percent
Durinodes - 10 to 40 percent
Effervescence - strong or violent
Calcium carbonate - 10 to 20 percent
Bkqm horizon
Laminar cap thickness - 1/16 to 2 inches
Texture below laminar cap - L, VFSL, or SIL
Effervescence - strong or violent
Calcium carbonate - 10 to 25 percent
COMPETING SERIES: These are the Burke, Dolman, Minidoka, and Nyssa series. Burke and Nyssa soils lack a calcic horizon. Dolman soils do not have free carbonates above 12 inches. Minidoka soils are 40 to 60 inches to bedrock.
GEOGRAPHIC SETTING: Sluka soils are on old dissected terraces and backslopes. These soils formed in old alluvium from mixed sources. Slopes are 1 to 50 percent. Elevations are 3,000 to 4,500 feet. The average annual precipitation is 8 to 10 inches. The average annual temperature is 48 to 51 degrees F., and the frost free period is 120 to 140 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Blacknest, Chuska, Dolman, Purdam, Rakane, Tulch, and Yahoo soils. Blacknest soils do not have a duripan. Chuska and Yahoo soils are shallow to a duripan. Purdam soils have fine-silty argillic horizons. Rakane soils have fine-loamy argillic horizons. All the above soils are on the same landform as Sluka. Tulch soils do not have a duripan, have fine-silty control sections, and are on lower terraces and larger drainageways.
DRAINAGE AND PERMEABILITY: Well drained; runoff is medium; permeability is moderate.
USE AND VEGETATION: Sluka soils are used for rangeland and irrigated crops. Native vegetation is Wyoming big sagebrush, Thurber needlegrass, and Sandberg bluegrass. Irrigated crops are mainly wheat, barley, sugar beets, potatoes, beans, and alfalfa hay.
DISTRIBUTION AND EXTENT: Sluka soils are of moderate extent in south central Idaho.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Portland, Oregon
SERIES ESTABLISHED: Twin Falls County, Idaho, 1992.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
Ochric epipedon - the zone from the soil surface to 4 inches (A horizon)
Cambic horizon - the zone from 4 to 11 inches (Bkq1 horizon)
Calcic horizon - the zone from 11 to 21 inches (Bkq2 horizon)
Duripan - the zone from 21 to 37 inches (Bkqm horizon)
Particle size control section - the zone from 10 to 21 inches (part of the Bkq1 and the Bkq2 horizon)