LOCATION BOWLAKE MTEstablished Series
TAXONOMIC CLASS: Fine, illitic, frigid Calcic Argixerolls
TYPICAL PEDON: Bowlake gravelly loam, in cropland (colors are for dry soil unless otherwise noted).
Ap--0 to 11 inches; grayish brown (10YR 5/2) gravelly loam, very dark grayish brown (10YR 3/2) moist; moderate fine and medium granular structure; soft, friable, slightly sticky and slightly plastic; many fine and medium roots; common fine pores; 5 percent cobbles and 10 percent gravel; neutral (pH 7.0); clear smooth boundary. (7 to 12 inches thick)
Bt/E--11 to 19 inches; B part (70 percent) is light brown (7.5YR 6/3) gravelly silty clay, brown (7.5YR 4/4) moist; E part (30 percent) pinkish gray (7.5YR 7/2) gravelly silty clay loam, brown (7.5YR 5/2) moist; color mixed is brown (7.5YR 5/4) moist; gravelly silty clay loam; moderate fine and medium subangular blocky structure; hard, firm, moderately sticky and moderately plastic; few coarse and common fine roots; many fine tubular pores; 10 percent gravel and 5 percent cobbles; slightly alkaline (pH 7.4); clear smooth boundary. (0 to 8 inches thick)
Bt1--19 to 26 inches; light brown (7.5YR 6/4) gravelly clay, brown (7.5YR 5/4) moist; weak medium prismatic structure parting to strong medium subangular blocky; hard, firm, moderately sticky and moderately plastic; common fine roots and few coarse roots; many fine tubular pores; common prominent clay films on faces of peds; 5 percent cobbles and 10 percent gravel; slightly alkaline (pH 7.6); clear smooth boundary. (7 to 15 inches thick)
Bt2--26 to 32 inches; light brown (7.5YR 6/4) gravelly clay, brown (7.5YR 5/4) moist; moderate fine and medium subangular blocky structure; hard, firm, moderately sticky and moderately plastic; common fine roots; many fine tubular pores; continuous distinct clay films in tubular pores and on faces of peds; 10 percent gravel and 5 percent cobbles; slightly alkaline (pH 7.8); clear wavy boundary. (0 to 15 inches thick)
Bk--32 to 51 inches; pink (7.5YR 7/4) gravelly clay, brown (7.5YR 5/4) moist; weak fine and medium subangular blocky structure; hard, firm, moderately sticky and moderately plastic; few fine roots; many fine tubular pores; 10 percent gravel and 5 percent cobbles; common fine masses and threads of lime; strongly effervescent; moderately alkaline (pH 8.0); clear smooth boundary. (10 to 20 inches thick)
C--51 to 60 inches; light brown (7.5YR 6/4) gravelly sandy clay loam, strong brown (7.5YR 5/6) moist; massive; slightly hard, friable, slightly sticky and slightly plastic; very few fine roots; few fine tubular pores; 15 percent gravel and 5 percent cobbles; slightly effervescent; moderately alkaline (pH 8.0).
TYPE LOCATION: Lake County, Montana; 1,000 feet south and 30 feet east of the NW corner of sec. 31, T. 23 N., R. 21 W.
RANGE IN CHARACTERISTICS:
Soil temperature - 41 to 45 degrees F.
Moisture control section - between 4 and 12 inches.
Mollic epipedon thickness - 7 to 12 inches.
Control section - 35 to 60 percent clay.
Depth to secondary carbonate accumulation - 15 to 35 inches.
Ap horizon - Value: 4 or 5 dry, 2 or 3 moist
Chroma: 2 or 3
Clay content: 20 to 27 percent
Rock fragments: 15 to 30 percent--0 to 10 percent cobbles and stones, 10 to 25 percent gravel
Reaction: pH 6.6 to 7.8
Bt/E horizon - Hue: B part 7.5YR or 10YR, E part 7.5YR or 10YR
Value: B part 5 or 6 dry, 4 or 5 moist; E part 7 or 8 dry, 5 or 6 moist
Chroma: B part 2, 3, or 4; E part 2 or 3,
Texture: silty clay loam, clay loam, or silty clay
Clay content: 30 to 40 percent
Rock fragments: 5 to 30 percent--0 to 10 percent cobbles and stones, 5 to 20 percent gravel
Reaction: pH 6.6 to 7.8
Bt horizon - Hue: 7.5YR or 10YR
Value: 5, 6, or 7 dry; 4 or 5 moist
Chroma: 3, 4, or 6
Texture: silty clay, silty clay loam, or clay
Clay content: 35 to 60 percent
Rock fragments: 5 to 25 percent--0 to 5 percent cobbles, 5 to 25 percent gravel
Reaction: pH 6.6 to 7.8
Bk horizon - Hue: 7.5YR or 10YR
Value: 6 or 7 dry; 4, 5 or 6 moist
Chroma: 3 or 4
Texture: clay loam, silty clay, or clay
Clay content: 30 to 45 percent
Rock fragments: 5 to 60 percent--0 to 5 percent cobbles, 5 to 55 percent gravel
Calcium carbonate equivalent: 5 to 15 percent
Reaction: pH 7.8 to 8.4
C horizon - Hue: 7.5YR or 10YR
Value: 6, 7, or 8 dry; 5, 6, or 7 moist
Chroma: 2, 3, 4, or 6
Texture: loam, clay loam, silty clay, silt loam, or sandy clay loam
Clay content: 20 to 45 percent
Rock fragments: 5 to 50 percent cobbles; 5 to 40 percent gravel
Calcium carbonate equivalent: 1 to 5 percent
Reaction: pH 7.9 to 8.4
COMPETING SERIES: There are no competing series.
GEOGRAPHIC SETTING:
Landform- dissected alluvial fans, stream terraces, drainageways and giant ripple marks
Elevation - 2,800 to 3,600 feet
Slope - 0 to 15 percent
Parent material - alluvium and tertiary sediments
Climate - long, cold winters; moist falls and springs; warm dry summers.
Mean annual precipitation - 13 to 18 inches
Mean annual air temperature - 39 to 46 degrees F.
Frost-free period - 80 to 125 days
GEOGRAPHICALLY ASSOCIATED SOILS:
DRAINAGE AND PERMEABILITY: Well drained; slow permeability.
USE AND VEGETATION: Bowlake soils are used mainly for rangeland and dryland pasture. The potential native vegetation is rough fescue, bluebunch wheatgrass, and Idaho fescue.
DISTRIBUTION AND EXTENT: Bowlake soils are of small extent. They are in the intermountain valleys and foothills of western Montana. MLRA 44A and 46.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Bozeman, Montana.
SERIES ESTABLISHED: Lake County, Montana, 1991; proposed Lake County, Montana, 1982.
REMARKS: Soil Interpretation Record: MT0749. Diagnostic horizons and features recognized in this pedon are: a mollic epipedon from the soil surface to 11 inches (Ap horizon); an argillic horizon from 11 to 32 inches (Bt/E, Bt1, and Bt2 horizons); and a horizon of carbonate accumulation from 32 to 51 inches (Bk horizon). Bowlake soils have a frigid temperature regime and a xeric moisture regime.
ADDITIONAL DATA: Laboratory data: S81MT-047-462