LOCATION DOKER MTEstablished Series
TAXONOMIC CLASS: Ashy over loamy, mixed, superactive, nonacid, frigid Typic Vitraquands
TYPICAL PEDON: Doker ashy silt loam, in pasture (colors are for moist soil unless otherwise noted).
A--0 to 7 inches; black (10YR 2/1) ashy silt loam, dark grayish brown (10YR 4/2) dry; common fine distinct dark yellowish brown (10YR 4/6) dry redox concentrations; moderate fine and medium granular structure; soft, very friable, slightly sticky and slightly plastic; many fine and medium roots; common very fine and fine tubular pores; slightly acid (pH 6.2); abrupt smooth boundary. (7 to 14 inches thick)
Bw--7 to 13 inches; dark yellowish brown (10YR 4/4) ashy silt loam, light yellowish brown (10YR 6/4) dry; common fine distinct yellowish brown (10YR 5/6) dry redox concentrations; weak medium subangular blocky structure; soft, very friable, nonsticky and slightly plastic; many fine and medium roots; common very fine tubular pores; slightly acid (pH 6.2); abrupt smooth boundary.
Bg--13 to 15 inches; dark grayish brown (2.5Y 4/2) ashy silt loam, light brownish gray (2.5Y 6/2) dry; many fine and medium prominent yellowish brown (10YR 5/6) dry redox concentrations, many medium prominent dark yellowish brown (10YR 4/6) and dark yellowish brown (10YR 3/6) redox concentrations in root channels; massive; slightly hard, firm, slightly sticky and slightly plastic; many fine and medium roots; common very fine tubular pores; 1/2- to 3/4-inch thick band of very dark gray (10YR 3/1) silt loam; slightly acid (pH 6.2); abrupt smooth boundary. (Combined Bs horizon 7 to 14 inches thick)
2Cg1--15 to 22 inches; dark gray (5Y 4/1) fine sandy loam, grayish brown (2.5Y 5/2) dry; many fine and medium prominent yellowish brown (10YR 5/6) redox concentrations, many medium prominent dark yellowish brown (10YR 4/6) and dark yellowish brown (10YR 3/6) redox concentrations in root channels; massive; soft, friable, slightly sticky and slightly plastic; many fine and medium roots; common very fine tubular pores; slightly acid (pH 6.2); clear smooth boundary. (5 to 30 inches thick)
2Cg2--22 to 38 inches; gray (5Y 5/1) fine sandy loam, light brownish gray (2.5Y 6/2) dry; few faint yellowish brown (10YR 5/6) redox concentrations; massive; soft, very friable, slightly sticky and nonplastic; neutral (pH 6.6); gradual smooth boundary. (0 to 20 inches thick)
2Cg3--38 to 60 inches; gray (5Y 5/1) fine sandy loam, light gray (5Y 7/1) dry; few faint yellowish brown (10YR 5/6) redox concentrations; massive; soft, very friable, nonsticky and nonplastic; neutral (pH 6.8).
TYPE LOCATION: Lake County, Montana; 450 feet west and 2,000 feet south of the NE corner of sec. 14, T. 21 N., R. 20 W.
RANGE IN CHARACTERISTICS:
Soil temperature - 43 to 47 degrees F.
Moisture control section - between 4 to 12 inches.
Depth to water table - 0 to 24 inches.
Some pedons have a 1 to 3 inch surface layer of peat or muck.
A horizon - Hue: 10YR or 2.5Y
Value: 2 or 3 moist; 3 or 4 dry
Chroma: 1 or 2
Clay content: 18 to 27 percent
Bulk density: less than .90 grams per cubic centimeter
Reaction: 6.1 to 7.3
Bs horizon - Hue: 10YR or 2.5Y
Value: 4 or 5 moist; 5 or 6 dry
Chroma: 4 or 6
Clay content: 5 to 10 percent
Bulk density: less than .9 grams per cubic centimeter
Reaction: 6.1 to 7.3
Bgs horizon - Hue: 10YR or 2.5Y
Value: 4 or 5 moist; 5 or 6 dry
Chroma: matrix chroma of 2--the gleying masks the high chroma matrix colors
Clay content: 5 to 10 percent
Bulk density: less than .9 grams per cubic centimeter
Reaction: 6.1 to 7.3
2Cg horizons - Hue: 10YR, 2.5Y, or 5Y
Value: 4 or 5 moist; 5, 6, or 7 dry
Chroma: 1 or 2
Clay content: 8 to 18 percent
Reaction: 6.1 to 7.3
COMPETING SERIES: There are no competing series.
GEOGRAPHIC SETTING: The Doker soils are on flood plains. Elevation is 2,950 to 3,100 feet. Slope is 0 to 2 percent. These soils formed in alluvium. Mean annual precipitation is 14 to 19 inches. Mean annual temperature is 40 to 45 degrees F. The frost-free season is 105 to 130 days.
GEOGRAPHICALLY ASSOCIATED SOILS:
DRAINAGE AND PERMEABILITY: Poorly drained; slow runoff; moderate permeability.
USE AND VEGETATION: These soils are used for pasture, rangeland, and hayland. The potential native vegetation is mainly tall reedgrass, mannagrass, tufted hairgrass, and sedges.
DISTRIBUTION AND EXTENT: Doker soils are of small extent in western Montana.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Bozeman, Montana
SERIES ESTABLISHED: Lake County, Montana, 1991; proposed in Lake County, Montana, 1990. Doker is a coined name.
REMARKS: Soil Interpretation Record MT1246. Diagnostic horizons and features recognized in this pedon are: a dark colored ash influenced surface layer from the surface to 7 inches (A horizon); an ash influenced layer from 7 to 15 inches (Bw and Bg horizons); a lithologic discontinuity from 15 to 60 inches (2Cg1, 2Cg2, and 2Cg3 horizons); a particle size control section from 0 to 40 inches (A, Bw, Bg, 2Cg1, 2Cg2, and 2Cg3 horizons). Doker soils have a frigid temperature regime and an aquic moisture regime.