LOCATION WHITECOW MT
Established Series
Rev. DES-BDD-EMM
04/2014
WHITECOW SERIES
The Whitecow series consists of very deep, well drained soils that formed in alluvium and colluvium from limestone. These soils are on mountains, hills, alluvial fan remnants, and alluvial fans. Slopes are 0 to 80 percent. Mean annual precipitation is about 20 inches, and mean annual temperature is about 41 degrees F.
TAXONOMIC CLASS: Loamy-skeletal, carbonatic, frigid Typic Calciustepts
TYPICAL PEDON: Whitecow gravelly loam, woodland (colors are for dry soil unless otherwise noted).
Oi--0 to 1 inch; undecomposed forest litter of needles and twigs. (0 to 3 inches thick)
A--1 to 4 inches; dark grayish brown (10YR 4/2) gravelly loam, very dark grayish brown (10YR 3/2) moist; weak medium and fine granular structure; soft, very friable, slightly sticky and slightly plastic; common fine roots, few medium roots; 25 percent subrounded gravel; slightly effervescent; moderately alkaline; clear smooth boundary. (2 to 10 inches thick)
Bk1--4 to 11 inches; grayish brown (10YR 5/2) very gravelly loam, dark grayish brown (10YR 4/2) moist; weak fine granular structure; soft, very friable, slightly sticky and slightly plastic; common fine roots; common fine pores; 40 percent angular gravel; 5 percent angular cobbles; continuous faint lime crusts on undersides of rock fragments; disseminated lime; violently effervescent; moderately alkaline; clear boundary. (3 to 15 inches thick)
Bk2--11 to 21 inches; light brownish gray (2.5Y 6/2) very gravelly loam, light olive brown (2.5Y 5/4) moist; moderate fine and medium subangular blocky structure; slightly hard, friable, moderately sticky and slightly plastic; few or common fine roots; common fine pores; 50 percent angular gravel, 5 percent angular cobbles; continuous distinct lime coats on rock fragments; disseminated lime; violently effervescent; moderately alkaline; gradual boundary. (6 to 20 inches thick)
Bk3--21 to 31 inches; light brownish gray (2.5Y 6/2) extremely gravelly loam, light olive brown (2.5Y 5/4) moist; weak fine and medium subangular blocky structure; slightly hard, friable, moderately sticky and slightly plastic; few fine roots; few fine pores; 70 percent angular gravel, 5 percent angular cobbles; continuous distinct lime coats on rock fragments; violently effervescent; moderately alkaline; gradual boundary. (15 to 25 inches thick)
Bk4--31 to 60 inches; light brownish gray (2.5Y 6/2) extremely gravelly loam, light olive brown (2.5Y 5/4) moist; massive; slightly hard, friable, moderately sticky and slightly plastic; few fine roots; few fine pores; 70 percent angular gravel, 5 percent angular cobbles; violently effervescent; moderately alkaline.
TYPE LOCATION: Blaine County, Montana; 500 feet west and 1,500 feet south of the NE corner of sec. 20, T. 26 N., R. 24 E.
RANGE IN CHARACTERISTICS:
Soil temperature - 38 to 45 degrees F.
Moisture control section - between 4 and 12 inches.
Surface stones or boulders - 0 to 3 percent
A Bw or a cambic horizon is present in some pedons.
A horizon
Hue: 10YR or 2.5Y
Value: 4, 5 or 6 dry, 3 or 4 moist
Chroma: 2 or 3
Clay content: 18 to 35 percent
Rock fragments: 15 to 65 percent--0 to 30 percent stones and cobbles, 5 to 35 percent gravel and channers
Calcium carbonate equivalent: 0 to 45 percent
Reaction: pH 7.4 to 8.4
Bk1, Bk2 horizons
Hue: 10YR or 2.5Y
Value: 5, 6 or 7 dry, 4, 5 or 6 moist
Chroma: 2, 3, or 4
Texture: loam or clay loam
Clay content: 18 to 35 percent
Rock fragments: 35 to 70 percent--0 to 30 percent stones and cobbles, 5 to 60 percent gravel and channers
Calcium carbonate equivalent: 35 to 50 percent
Reaction: pH 7.4 to 9.0
Bk3, Bk4 horizons
Hue: 10YR or 2.5Y
Value: 6, 7, or 8 dry; 4, 5, 6, or 7 moist
Chroma: 2, 3, 4 or 6
Texture: loam, sandy loam, or clay loam
Clay content: 18 to 35 percent
Rock fragments: 35 to 90 percent--5 to 30 percent stones and cobbles, 25 to 70 percent gravel and channers
Calcium carbonate equivalent: 40 to 50 percent
Reaction: pH 7.4 to 9.0
COMPETING SERIES: There are no competing series.
GEOGRAPHIC SETTING:
Landform - mountains; hills; alluvial fan remnants, alluvial fans.
Elevation - 3,500 to 8,600 feet.
Slope - 0 to 80 percent.
Parent material - alluvium or colluvium from limestone and dolomite.
Climate - long, cold winters; moist springs; warm summers.
Mean annual precipitation - 12 to 30 inches.
Mean annual temperature - 37 to 43 degrees F.
Frost-free period - 70 to 115 days.
GEOGRAPHICALLY ASSOCIATED SOILS: None listed.
DRAINAGE AND PERMEABILITY: Well drained; moderate permeability.
USE AND VEGETATION: Whitecow soils are used mainly for woodland and range. Potential native vegetation is mainly ponderosa pine, Douglas-fir, and lodgepole pine with an understory and open area of bluebunch wheatgrass, pinegrass, Idaho fescue, rough fescue, Saskatoon, serviceberry, common chokecherry, arrowleaf balsamroot, common snowberry, kinnikinnick, woods rose, and other shrubs.
DISTRIBUTION AND EXTENT: Whitecow soils are extensive in central and western Montana. MLRAs 43B, 44B, and 46.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Bozeman, Montana
SERIES ESTABLISHED: Blaine County, Montana, 1976.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
Ochric epipedon - from the soil surface to 7 inches mixed (A, Bk1 horizons);
Calcic horizon with carbonatic mineralogy - from 3 to 60 inches (Bk1, Bk2, Bk3, Bk4 horizons);
Particle-size control section - from 10 to 40 inches (Bk2, Bk3, Bk4 horizons).
Whitecow soils have a frigid temperature regime and an ustic moisture regime.
Soil interpretations records: MT0172, MT0887, MT0364, MT0728.
National Cooperative Soil Survey
U.S.A.