LOCATION BRODYK MTEstablished Series
TAXONOMIC CLASS: Coarse-silty, mixed, superactive, frigid Typic Calciustepts
TYPICAL PEDON: Brodyk silt loam in cropland (colors are for dry soil unless otherwise indicated).
Ap--0 to 6 inches; brown (10YR 5/3) silt loam, dark grayish brown (10YR 4/2) moist; weak medium platy structure; soft, very friable, slightly sticky and slightly plastic; many very fine and fine roots; strongly effervescent; slightly alkaline (pH 7.8); abrupt smooth boundary. (5 to 7 inches thick)
Bk1--6 to 30 inches; pale brown (10YR 6/3) silt loam, brown (10YR 5/3) moist; weak medium subangular blocky structure; soft, very friable, slightly sticky and nonplastic; common very fine and fine roots; common fine masses of lime; violently effervescent; moderately alkaline (pH 8.4); gradual wavy boundary. (15 to 25 inches thick)
Bk2--30 to 60 inches; light gray (10YR 7/2) silt loam, brown (10YR 5/3) moist; weak fine subangular blocky structure; soft, very friable, slightly sticky and nonplastic; few very fine roots; dissemenated lime; few fine seams of lime; violently effervescent; moderately alkaline (pH 8.4).
TYPE LOCATION: Gallatin County, Montana; 1,500 feet east and 1,900 feet north of the SW corner of sec. 12, T.2N., R.4E.
RANGE IN CHARACTERISTICS:
Mean annual soil temperature - 41 to 45 degrees F.
Moisture control section - between 4 and 12 inches.
Depth to calcic horizon - 5 to 7 inches.
Ap horizon - Value: 5 or 6 dry
Chroma: 2 or 3
Clay content: 18 to 22 percent
Reaction: 7.4 to 8.4
Bk1 horizon - Value: 6 or 7 dry
Clay content: 10 to 18 percent
CaCO3 equivalent: 15 to 30 percent
Reaction: 7.9 to 8.4
Bk2 horizon - Value: 6 or 7 dry, 5 or 6 moist
Chroma: 2 or 3
Texture: silt loam, very fine sandy loam
Clay content: 10 to 18 percent
Rock fragments: 0 to 5 percent pebbles
CaCO3 equivalent: 15 to 30 percent
Reaction: 7.9 to 8.4
COMPETING SERIES: There are no competing series.
GEOGRAPHIC SETTING:
Landform - relict stream terraces.
Elevation - 4,600 to 5,700 feet.
Parent material - loess.
Slope - 4 to 45 percent.
Climate - long cold winters; moist springs; warm summers.
Mean annual precipitation - 14 to 18 inches.
Mean annual air temperature - 39 to 43 degrees F.
Frost-free period - 90 to 110 days.
DRAINAGE AND PERMEABILITY: Well drained; moderate permeability.
USE AND VEGETATION: Brodyk soils are used mainly for nonirrigated cropland. The potential native vegetation is mainly bluebunch wheatgrass, Idaho fescue, western wheatgrass, and prairie junegrass.
DISTRIBUTION AND EXTENT: Brodyk soils are of small extent in southwestern Montana.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Bozeman, Montana
SERIES ESTABLISHED: Gallatin County, Montana, 1997.
REMARKS: Soil interpretation record: MT1445. Diagnostic horizons and features recognized in this pedon are: an ochric epipedon from the surface to 6 inches (Ap horizon); a calcic horizon from 6 to 60 inches (Bk1, Bk2 horizons); a coarse-silty particle size control section from 10 to 40 inches (Bk1, Bk2 horizons). Brodyk soils have a frigid temperature regime and an ustic moisture regime.