LOCATION WILSPRING          MT 
Established Series
Rev. DES-BDD-JAL
03/1999

WILSPRING SERIES


The Wilspring series consists of moderately deep, well drained soils that formed in slope alluvium, colluvium or residuum derived from hard brown shale or argillite. These soils are on escarpments, ridges, sideslopes of hills and mountains. Slopes are 2 to 75 percent. Mean annual precipitation is about 16 inches, and mean annual temperature is about 40 degrees F.

TAXONOMIC CLASS: Loamy-skeletal, mixed, superactive, frigid Typic Haplustepts

TYPICAL PEDON: Wilspring channery loam, in rangeland (colors are for dry soil unless otherwise noted).

A--0 to 3 inches; dark grayish brown (10YR 4/2) channery loam, dark brown (10YR 3/3) moist; moderate medium granular structure; slightly hard, very friable, nonsticky and nonplastic; many fine and very fine roots; many fine and very fine interstitial pores; 5 percent flagstone, 20 percent channers; slightly effervescent; slightly alkaline (pH 7.8); clear wavy boundary. (3 to 5 inches thick)

Bw--3 to 7 inches; brown (10YR 5/3) channery loam, brown (10YR 4/3) moist; moderate medium subangular blocky structure; slightly hard, very friable, slightly sticky and slightly plastic; many fine and very fine roots; common to many fine and very fine tubular and interstitial pores; 5 percent flagstone, 20 percent channers; slightly effervescent; moderately alkaline (pH 8.0); clear wavy boundary. (3 to 7 inches thick)

Bk1--7 to 12 inches; pale brown (10YR 6/3) very channery loam, yellowish brown (10YR 5/4) moist; moderate medium subangular blocky structure; slightly hard, very friable, slightly sticky and nonplastic; many fine and very fine roots; common to many fine and very fine tubular and interstitial pores; 5 percent flagstones, 35 percent channers; disseminated lime, common distinct lime coatings on underside of rock fragments; strongly effervescent; moderately alkaline (pH 8.3); gradual wavy boundary.

Bk2--12 to 24 inches; light gray (10YR 7/2) very channery loam, light yellowish brown (10YR 6/4) moist; weak medium subangular blocky structure; slightly hard, very friable, slightly sticky and nonplastic; common to many very fine roots; few to common fine and very fine tubular and interstitial pores; 5 percent flagstones, 45 percent channers; disseminated lime, few fine masses of lime, continuous distinct lime crusts on surfaces of rock fragments; violently effervescent; moderately alkaline (pH 8.4); clear smooth boundary. (Combined thickness of Bk horizons is 13 to 20 inches.)

R--24 inches; brown (10YR 5/3) hard fractured shale.

TYPE LOCATION: Jefferson County, Montana; 2,300 feet north and 2,000 feet east of the southwest corner of sec. 35, T. 4 N., R. 2 W.

RANGE IN CHARACTERISTICS:

Annual soil temperature - 38 to 43 degrees F.

Moisture control section - between 4 and 12 inches.

Depth to Bk horizon - 7 to 10 inches.

Depth to bedrock - 20 to 40 inches.

The surface horizon, when mixed to a depth of 7 inches, does not meet the requirements of a mollic epipedon.

A horizon - Value: 4 or 5 dry

Chroma: 2, 3, or 4

Clay content: 15 to 27 percent

Rock fragments: 15 to 45 percent--0 to 5 percent flagstone, 15 to 40 percent channers or pebbles

Calcium carbonate equivalent: 0 to 5 percent

Reaction: pH 7.4 to 8.4

Bw horizon - Value: 5 or 6 dry

Chroma: 2 or 3

Texture: loam or clay loam

Clay content: 15 to 30 percent

Rock fragments: 15 to 45 percent--0 to 5 percent flagstone, 15 to 40 percent channers

Calcium carbonate equivalent: 5 to 10 percent

Reaction: pH 7.4 to 8.4

Bk horizons - Value: 5, 6, or 7 dry; 4, 5, or 6 moist

Chroma: 2, 3, 4, 5, or 6

Texture: sandy loam, loam, or clay loam

Clay content: 18 to 30 percent

Rock fragments: 35 to 80 percent--0 to 10 percent flagstones; 30 to 70 percent channers

Calcium carbonate equivalent: 5 to 15 percent

Reaction: pH 7.9 to 8.4

COMPETING SERIES:

Kadygulch (MT) - does not have a lithic contact above 60 inches.

Kingspoint (MT) - does not have a lithic contact above 60 inches; has albic horizons.

Mowbray (MT) - does not have a lithic contact above 60 inches; is not calcareous above a depth of 10 inches.

Repkie (MT) - does not have a lithic contact above 60 inches; has less than 18 percent clay in particle-size control section.

Repp (MT) - does not have a lithic contact above 60 inches; has albic horizons 6 to 15 inches thick.

Specie (CO) - does not have a lithic contact above 60 inches.

Wilde (MT) - is non calcareous throughout.

Wildgen (MT) - has a cambic horizon consisting of lamellae, does not have a lithic contact above 60 inches.

GEOGRAPHIC SETTING:

Landform - escarpments, ridges and sideslopes of hills and mountains.

Elevation - 4,400 to 6,600 feet.

Slope- 2 to 75 percent.

Parent material - residuum, colluvium, or slope alluvium from hard brown shale or argillite.

Climate - long, cold winters; moist springs; warm summers.

Mean annual precipitation - 15 to 19 inches.

Mean annual air temperature - 37 to 45 degrees F.

Frost-free period - 70 to 105 days.

DRAINAGE AND PERMEABILITY: Well drained, moderate permeability.

USE AND VEGETATION: Wilspring soils are primarily used for rangeland. Native vegetation is mainly bluebunch wheatgrass, Idaho fescue, needleandthread, Sandberg bluegrass, western yarrow, big sagebrush, and common juniper. Some areas have an overstory of low density stands of Douglas fir and limber pine.

DISTRIBUTION AND EXTENT: Wilspring soils are of small extent in southwestern Montana.

MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Bozeman, Montana

SERIES ESTABLISHED: Jefferson County, Montana, 1998.

REMARKS: Soil interpretation record: MT1590. Diagnostic horizons and features recognized in this pedon are: an ochric horizon from the soil surface to 7 inches, mixed (A, Bw horizons); a cambic horizon from 3 to 12 inches (Bw, Bk1 horizons); a particle-size control section from 10 to 24 inches (Bk horizons); a layer of secondary carbonate accumulation from 12 to 24 inches (Bk1, Bk2 horizons); hard, fractured shale bedrock at 24 inches (R horizon). Wilspring soils have a frigid temperature regime and an ustic moisture regime.


National Cooperative Soil Survey
U.S.A.