LOCATION WILSONGULCH        ID

Established Series
REV. FRK/GHL/TM
03/2009

WILSONGULCH SERIES

The Wilsongulch series consists of deep and very deep, well-drained moderately permeable soils. They formed in ashy alluvium and residuum, modified by rock fragments of quartz latite, on steep, south-facing mesa sides and hillsides and have slopes of 20 to 60 percent. The average annual temperature is about 46 degrees F, and the average annual precipitation is about 14 inches.

TAXONOMIC CLASS: Ashy-skeletal, glassy, mesic Vitrandic Haploxerolls

TYPICAL PEDON: Wilsongulch very stony loam - range. On a 45 percent concave slope, southwest aspect, 5,500 feet elevation. (Colors are for air dry soil unless otherwise stated. This profile was described on August 29, 1979.)

A--0 to 7 inches; brown (10YR 4/3) very stony loam, dark brown (10YR 3/3) moist; weak very fine granular structure; soft and very friable; many very fine and fine roots; many very fine irregular pores; Class 4 stones, 10 percent cobbles, 25 percent pebbles; moderately alkaline (pH 8.0 with phenol red); gradual smooth boundary. (2 to 9 inches thick)

Bw--7 to 14 inches; brown (10YR 5/3) very gravelly loam, dark brown (10YR 3/3) moist; weak fine subangular blocky structure; soft and very friable; many very fine and few fine roots; many very fine tubular pores; 30 percent cobbles, 30 percent pebbles); moderately effervescent; moderately alkaline (pH 8.2 with phenol red); clear wavy boundary. (5 to 8 inches thick)

Bk1--14 to 27 inches; very pale brown (10YR 8/2) very gravelly loam, pale brown (10YR 6/3) moist; massive; slightly hard, very friable, slightly plastic; common very fine roots; common very fine tubular pores; 20 percent cobbles, 30 percent pebbles; strongly effervescent; moderately alkaline (pH 8.2 with phenol red); abrupt wavy boundary. (7 to 14 inches thick)

Bk2--27 to 60 inches; very pale brown (10YR 8/2) very gravelly sandy loam, pale brown (10YR 6/3) moist; massive; soft and very friable; common very fine roots; common very fine tubular pores; 15 percent cobbles 20 percent pebbles; strongly effervescent; moderately alkaline (pH 8.4 with phenol red); clear smooth boundary. (31 to 45 inches thick)

TYPE LOCATION: Cassia County, Idaho; about 7 miles south of Oakley, Idaho, about 2,300 feet east and 1,700 feet south of the northwest corner of sec. 5, T.16S., R.22E.; lat. 42 degrees 03 minutes 53.9 seconds N and long. 113 degrees 54 minutes 11.9 seconds W, NAD83.

RANGE IN CHARACTERISTICS:
Average Annual soil temperature - 47 to 50 degrees F
Thickness of the mollic epipedon - 7 to 14 inches
Rock fragment content - 35 to 60 percent
Reaction - with sodium fluoride - less than 9.5

A horizons
Value - 4 or 5 dry, 2 or 3 moist
Chroma - 2 or 3
Reaction - mildly to moderately alkaline

Bw horizons
Value - 5 or 6 dry, 2 or 3 moist
Chroma - 2 or 3
Texture - GRV-L, GRV-SL, CBV-L and CBV-SL
Rock fragment content - 35 to 60 percent

Bk horizons
Hue - 10YR or 2.5Y
Value - 6 through 8 dry, 6 or 7 moist
Chroma - 2 through 4
Texture - GRV-L, GRV-SL, CBV-SL, STV-SL
Rock fragment content - 35 to 60 percent
Effervescence - strongly to violently

COMPETING SERIES: There are no competing series.

GEOGRAPHIC SETTING: Wilsongulch soils are on steep south-facing mesa sides and hillsides. Slopes range from 20 to 60 percent. Elevation ranges from 5,100 to 5,900 feet. The soils formed in alluvium and residuum from volcanic ash modified by rock fragments of quartz latite. The average annual precipitation is about 12 to 16 inches, the average annual air temperature is about 45 to 46 degrees F, and the frost-free season is 95 to 115 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Coalbank, Bluehill, Cottonthomas and Tomsherry series and the Stines(T) series. Bluehill soils are moderately deep to a paralithic contact. Coalbank, Cottonthomas, Stines and Tomsherry soils are frigid. Tomsherry soils have a duripan at a depth of 20 to 40 inches. Coalbank and Stines soils are on steep northerly slopes, Bluehill soils are on steep southerly slopes. Tomsherry soils are on fan terraces.

DRAINAGE AND PERMEABILITY: Well drained; moderate to rapid runoff; moderate or moderately rapid permeability.

USE AND VEGETATION: Wilsongulch soils are used for range. The natural vegetation is Wyoming big sagebrush, bluebunch wheatgrass, Indian ricegrass, Sandberg bluegrass and Nevada bluegrass.

DISTRIBUTION AND EXTENT: Wilsongulch soils are found in southern Idaho. They are not extensive.

MLRA OFFICE RESPONSIBLE: Reno, Nevada

SERIES ESTABLISHED: Cassia County, Idaho, 1986.

REMARKS:

Revision 3/2009 added geographic coordinates only.

Diagnostic horizons and features recognized in this pedon
are:

Mollic Epipedon - the zone from the surface to 11 inches (A and Bw horizons)
Control Section - 10 to 40 inches (Bw, Bk1 and part of the Bk2
horizons)
Andic feature - greater than 60 percent vitric material
Reaction with sodium fluoride - pH less than 9.5

National Cooperative Soil Survey
U.S.A.