LOCATION MURPHILL IDEstablished Series
TAXONOMIC CLASS: Loamy-skeletal, mixed, superactive, mesic Lithic Xeric Haplocalcids
TYPICAL PEDON: Murphill very gravelly fine sandy loam -- on a convex south-facing slope of 5 percent, in native rangeland at 2,820 feet elevation. The surface has gravelly desert pavement. (When described on November 3, 1978, the soil was dry throughout. Colors are for air dry soil unless otherwise stated.)
A--0 to 3 inches; light yellowish brown (2.5Y 6/4) very gravelly fine sandy loam, olive brown (2.5Y 4/4) moist; moderate fine platy structure parting to moderate fine granular; slightly hard, very friable, slightly sticky and slightly plastic; few very fine and fine roots; many very fine and fine vesicular and interstitial pores; 30 percent gravel, 5 percent cobbles; strongly effervescent; mildly alkaline (pH 7.8); clear smooth boundary. (2 to 6 inches thick)
Bk1--3 to 9 inches; yellowish brown (10YR 5/4) very gravelly fine sandy loam, dark yellowish brown (10YR 3/4) moist; weak fine and medium subangular blocky structure parting to moderate fine granular; slightly hard, very friable; few very fine and fine roots; common very fine and fine vesicular and interstitial pores; 40 percent gravel; violently effervescent; moderately alkaline (pH 8.2); clear wavy boundary. (4 to 10 inches thick)
Bk2--9 to 14 inches; yellowish brown (10YR 5/4) extremely gravelly loamy sand, dark yellowish brown (10YR 3/4) moist; massive; few very fine and fine roots; 70 percent gravel, 10 percent cobbles; violently effervescent, lime segregated in common fine seams; moderately alkaline (pH 8.4); clear wavy boundary. (4 to 10 inches thick)
R--14 inches; moderately fractured vitric tuff, lime and silica fill most fractures.
TYPE LOCATION: Owyhee County, Idaho; about 3 miles south and 1 mile west of Walter's Ferry; 900 feet south and 800 feet west of the northeast corner of sec. 31, T.1S., R.2W.
RANGE IN CHARACTERISTICS:
Average annual soil temperature - 50 to 55 degrees F.
Depth to bedrock - 10 to 20 inches
Hue - 2.5Y or 10YR
Value - 5 or 6 dry, 3 or 4 moist
Chroma - 2 through 4
A horizon
Rock fragments - 35 to 60 percent
Effervescence - none to strong
Reaction (pH) - neutral or mildly alkaline
Bk horizon
Texture - GRV-FSL, GRX-LS, GRV-SL
Clay content - 7 to 18 percent clay
Rock fragments - 40 to 80 percent
Reaction (pH) - mildly or moderately alkaline
COMPETING SERIES: These are the Hoovers (T) and Rochpah series. Hoovers soils have 18 to 34 percent clay in the control section. Rochpah soils have an average annual soil temperature of 55 to 59 degrees F. and are moist for 10 to 20 days in summer following convection storms.
GEOGRAPHIC SETTING: Murphill soils are undulating to steep on summits and shoulders of foothills and of knolls on structural benches at elevations of 2,300 to 4,500 feet. Slopes range from 2 to 35 percent. These soils formed in residuum from vitric tuffs and basalt. The climate is cool and moist in the winter and hot and dry in the summer. Average annual precipitation is 8 to 10 inches, and average annual temperature is 48 to 53 degrees F. Frost-free period is 105 to 150 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Briabbit (T) and Hardtrigger (T) series. Briabbit soils are greater than 20 inches and Hardtrigger greater than 40 inches deep to bedrock. Both are on sideslope positions.
DRAINAGE AND PERMEABILITY: Well drained; medium to very rapid runoff; moderately rapid permeability.
USE AND VEGETATION: Murphill soils are used mainly for rangeland and wildlife habitat. The dominant natural vegetation is Wyoming big sagebrush, Indian ricegrass, bottlebrush squirreltail, and littleleaf horsebrush.
DISTRIBUTION AND EXTENT: Southwestern Idaho. Murphill soils are of small extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Portland, Oregon
SERIES ESTABLISHED: Owyhee County Area, Idaho, 1992.
REMARKS: Diagnostic horizons and other features recognized in this pedon:
Calcic horizon - zone 3 to 14 inches (Bk1 and Bk2 horizons)
Particle-size control section - 0 to 14 inches (A1, Bk1, and Bk2 horizons)