LOCATION HUFFMAN IDEstablished Series
TAXONOMIC CLASS: Fine-silty, mixed, superactive, frigid Calcic Haploxerolls
TYPICAL PEDON: Huffman silt loam--on a 1 percent northeast-facing slope at 5,060 feet elevation--cropland. (Colors are for dry soil unless otherwise noted. When described on June 15, 1987, the soil was dry in the upper one inch and moist below.)
Ap1--0 to 7 inches; brown (10YR 4/3) silt loam, dark brown (10YR 3/3) moist; moderate fine granular structure; slightly hard, very friable; slightly sticky and slightly plastic; common very fine roots; many very fine irregular and common fine irregular and tubular pores; slightly alkaline (pH 7.8); abrupt smooth boundary. (4 to 10 inches thick)
Ap2--7 to 12 inches; brown (10YR 4/3) silt loam, dark brown (10YR 3/3) moist; moderate medium and thick platy structure; hard, friable; slightly sticky and slightly plastic; many very fine roots; many very fine irregular pores; slightly alkaline (pH 7.8); abrupt smooth boundary. (4 to 10 inches thick)
Bw1--12 to 17 inches; brown (10YR 4/3) silt loam, dark brown (7.5YR 3/2) moist; moderate very fine subangular blocky structure; hard, very friable; slightly sticky and slightly plastic; common very fine roots; many very fine irregular and few fine tubular pores; slightly alkaline (pH 7.8); gradual smooth boundary. (3 to 10 inches thick)
Bw2--17 to 28 inches; brown (7.5YR 5/4) silt loam, brown (7.5YR 4/4) moist; moderate fine subangular blocky structure; hard, firm, moderately sticky and moderately plastic; common very fine roots; common very fine irregular pores; moderately alkaline (pH 8.0); clear smooth boundary. (9 to 15 inches thick)
Bk1--28 to 37 inches; pink (7.5YR 7/4) silty clay loam, brown (7.5YR 5/4) moist; moderate fine subangular blocky structure; hard, firm, moderately sticky and moderately plastic; common very fine roots; common very fine tubular pores; common fine carbonate masses and filaments; violently effervescent (20 percent calcium carbonate equivalent); strongly alkaline (pH 8.6); abrupt smooth boundary. (6 to 18 inches thick)
Bk2--37 to 60 inches; pink (7.5YR 7/4) silty clay loam, brown (7.5YR 5/4) moist; layers of light reddish brown (2.5YR 6/4), reddish brown (2.5YR 5/4) moist; moderate thin and medium platy structure; hard, firm, moderately sticky and moderately plastic; few very fine roots; common very fine and fine tubular pores; common fine carbonate masses and filaments; violently effervescent (26 percent calcium carbonate equivalent); strongly alkaline (pH 8.6).
TYPE LOCATION: Franklin County, Idaho; about 0.75 mile north of Thatcher; approximately 1,300 feet north and 1,200 feet west of the southeast corner of section 36, T. 11 S., R. 40 E.; USGS Thatcher 7.5 minute topographic quadrangle; 42 degrees 25 minutes 11 seconds north latitude and 111 degrees 43 minutes 31 seconds west longitude, NAD83.
RANGE IN CHARACTERISTICS:
Mean annual soil temperature - 42 to 45 degrees F.
Mollic epipedon thickness - 9 to 20 inches.
Depth to secondary carbonates - 15 to 30 inches.
Particle-size control section - Clay content: Averages 24 to 34 percent.
A horizons
Value: 4 or 5 dry, 2 or 3 moist.
Chroma: 2 or 3, dry or moist.
Bw horizons
Hue: 7.5YR through 2.5YR.
Value: 4 through 6 dry, 3 or 4 moist.
Chroma: 2 through 4, dry or moist.
Bk horizons
Hue: 7.5YR through 2.5YR.
Value: 6 or 7 dry, 5 or 6 moist.
Chroma: 3 or 4, dry or moist.
Calcium carbonate equivalent: 15 to 30 percent.
COMPETING SERIES: This is the Truscreek series. Truscreek soils have C horizons with fine stratification.
GEOGRAPHIC SETTING: Huffman soils are on hills and lake terraces. These soils formed in silty alluvium and loess derived from mixed sources. Slopes are 0 to 30 percent. Elevations range from 4,900 to 5,500 feet. The mean annual precipitation is 14 to 18 inches, the mean annual air temperature is 40 to 45 degrees F., and the frost-free period is 70 to 100 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Brifox, Lanoak, Manila, and Oxford soils. Brifox, Manila, and Oxford soils have more than 35 percent clay in the control section. Lanoak soils have a mollic epipedon 20 inches or more thick.
DRAINAGE AND PERMEABILITY: Well drained; low through high surface runoff; moderately slow permeability (moderately high saturated hydraulic conductivity).
USE AND VEGETATION: Huffman soils are used for dryland crops and rangeland. The native vegetation is basin and mountain big sagebrush, bluebunch wheatgrass, rabbitbrush, and geranium.
DISTRIBUTION AND EXTENT: Southeastern Idaho. These soils are not extensive with about 3,400 acres of the series mapped to date. MLRAs 13 and 28A.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Portland, Oregon
SERIES ESTABLISHED: Oneida County, Idaho, 1994.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
Mollic epipedon - The zone from the soil surface to 17 inches (Ap1, Ap2, and Bw1 horizons).
Cambic horizon - The zone from 17 to 28 inches (Bw2 horizon).
Calcic horizon - The zone from 28 to 60 inches (Bk1 and Bk2 horizons).
Particle-size control section - The zone from 10 to 40 inches (Bw1, Bw2, and Bk1 horizons, and parts of the Ap2 and Bk2 horizons).
A previous revision moved the type location from Oneida County, Idaho to Franklin County, Idaho.