LOCATION BLOSSBERG MT
Established Series
Rev. ADI-KTS-RJS
05/2013
BLOSSBERG SERIES
The Blossberg series consists of very deep, poorly drained soils on flood plains, depressions, drainageways, alluvial fans and stream terraces. These soils formed in loamy alluvium 20 to 40 inches deep over sand and gravel. Slope is 0 to 4 percent. Mean annual precipitation is about 12 inches, and mean annual air temperature is about 41 degrees F.
TAXONOMIC CLASS: Fine-loamy over sandy or sandy-skeletal, mixed, superactive, frigid Typic Endoaquolls
TYPICAL PEDON: Blossberg loam, 0 to 4 percent slopes, in pasture (colors are for moist soil unless otherwise noted).
A--0 to 14 inches; black (10YR 2/1) loam, very dark gray (10YR 3/1) dry; many large prominent yellowish brown (10YR 5/6) redox concentrations, dry; moderate fine granular structure; slightly hard, very friable, slightly sticky and slightly plastic; many very fine, fine, medium, and coarse roots, many very fine and fine irregular pores; neutral (pH 7.2); clear smooth boundary. (6 to 15 inches thick)
Bg1--14 to 23 inches; dark grayish brown (2.5Y 4/2) loam, grayish brown (2.5Y 5/2) dry; many coarse prominent yellowish brown (10YR 5/8) redox concentrations, dry; moderate medium subangular blocky structure; slightly hard, very friable, slightly sticky and moderately plastic; many very fine roots; many very fine and fine irregular pores; 5 percent cobbles; slightly alkaline (pH 7.6); gradual smooth boundary.
Bg2--23 to 28 inches; grayish brown (2.5Y 5/2) gravelly loam, light brownish gray (2.5Y 6/2) dry; few fine prominent red (2.5YR 5/8) redox concentrations, dry; moderate medium subangular blocky structure; slightly hard, very friable, slightly sticky and moderately plastic; many very fine and fine roots; many very fine and fine irregular pores; 20 percent gravel and 5 percent cobbles; slightly alkaline (pH 7.6); gradual wavy boundary. (Combined thickness of Bg horizons is 10 to 30 inches.)
2Cg--28 to 60 inches; dark grayish brown (10YR 4/2) very cobbly loamy coarse sand, light brownish gray (10YR 6/2) dry; common coarse prominent red (2.5YR 5/8) redox concentrations, dry; single grain; loose, nonsticky and nonplastic; many very fine and fine roots; many very fine and fine irregular pores; 20 percent gravel, 35 percent cobbles; slightly alkaline (pH 7.6).
TYPE LOCATION: Powell County, Montana; 2,400 feet south and 200 feet west of the NE corner of sec. 6, T. 6 N., R. 9 W.
RANGE IN CHARACTERISTICS:
Soil temperature - 41 to 47 degrees F.
Depth to seasonal high water table - 12 to 24 inches
Depth to 2Cg - 20 to 40 inches
Mollic epipedon thickness - 10 to 24 inches
Does not effervesce in all parts between 10 and 20 inches
A horizon
Value: 2 or 3 moist; 3 to 5 dry
Redox concentrations: 10YR 4/4 or 10YR 4/6 moist; 10YR 5/6 or 10YR 5/8 dry
Texture: silty clay loam, clay loam or loam
Clay content: 18 to 35 percent
Rock fragments: 0 to 15 percent--0 to 10 percent gravel, 0 to 5 percent cobbles
Calcium carbonate equivalent: 0 to 5 percent
Reaction: pH 6.6 to 8.0
Bg1 horizon
Hue: 2.5Y, 5Y or 10YR; dry or moist
Value: 3 or 4 moist; 3 to 6 dry
Chroma: 2 or 3; dry or moist
Redox concentrations: 10YR 4/4 or 10YR 4/6, moist; 10YR 5/6 or 10YR 5/8 dry
Texture: clay loam, loam or silty clay loam
Clay content: 18 to 35 percent
Rock fragments: 0 to 15 percent--0 to 10 percent gravel, 0 to 5 percent cobbles
Calcium carbonate equivalent: 0 to 15 percent
Reaction: pH 6.6 to 8.4
Bg2 horizon
Hue: 2.5Y, 5Y, or 10YR; dry or moist
Value: 4 or 5 moist; 5 or 6 dry
Chroma: 1 or 2; dry or moist
Redox concentrations: 2.5YR 4/6, 2.5YR 4/8 moist; 2.5YR 5/6, 2.5YR 5/8 dry
Texture: loam, sandy loam or sandy clay loam
Clay content: 10 to 35 percent
Rock fragments: 0 to 40 percent--0 to 25 percent gravel, 0 to 15 percent cobbles
Calcium carbonate equivalent: 0 to 10 percent
Reaction: pH 6.6 to 8.4
2Cg horizon
Value: 5 or 4 moist; 6 or 7 dry
Chroma: 2 to 4; dry or moist
Redox concentrations: 2.5YR 4/6 or 2.5YR 4/8 moist; 2.5YR 5/6 or 2.5YR 5/8 dry
Texture: coarse sand, loamy coarse sand or sand
Clay content: 0 to 10 percent
Rock fragments: 35 to 80 percent--15 to 50 percent gravel, 20 to 35 percent cobbles
Calcium carbonate equivalent: 0 to 5 percent
Reaction: pH 6.6 to 8.4
COMPETING SERIES:
Gerrard (CO) - do not have a cambic horizon
Vastine (CO) - has a lithologic discontinuity of sand with less than 15 percent coarse fragments at a depth of 20 to 40 inches.
GEOGRAPHIC SETTING:
Landform - flood plains, depressions, drainageways, alluvial fans and stream terraces
Elevation - 3,350 to 6,000 feet
Slope - 0 to 4 percent
Parent material - loamy alluvium that is 20 to 40 inches deep over sand and gravel
Mean annual precipitation - 10 to 19 inches
Mean annual air temperature - 39 to 45 degrees F.
Frost-free period - 70 to 110 days
GEOGRAPHICALLY ASSOCIATED SOILS: None listed.
DRAINAGE AND PERMEABILITY: Poorly drained; moderately slow permeability above the sandy-skeletal materials and rapid in the sandy-skeletal material.
USE AND VEGETATION: Blossberg soils are used mainly for pasture and hayland. Potential native vegetation is mainly reedgrass, tufted hairgrass, prairie cordgrass, sedges and shrubs.
DISTRIBUTION AND EXTENT: Blossberg soils are of moderate extent in mountain valleys of Western Montana. MLRAs 43B and 44B.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Bozeman, Montana.
SERIES ESTABLISHED: Powell County, Montana, 1995.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
Mollic epipedon - from 0 to 14 inches (A horizon)
Cambic horizon - from 14 to 28 inches (Bg1 and Bg2 horizons)
Lithologic discontinuity - from 28 to 60 inches (2Cg horizon)
Particle-size control section from 10 to 40 inches (part of A, Bg1, Bg2 and part of 2Cg horizons)
Blossberg soils have a frigid temperature regime and an aquic moisture regime.
ADDITIONAL DATA: Laboratory data - S88MT-077-1216; Soil interpretation record - MT1273.
National Cooperative Soil Survey
U.S.A.