LOCATION MASCHETAH MTEstablished Series
TAXONOMIC CLASS: Fine-silty, mixed, superactive, frigid Typic Calciustolls
TYPICAL PEDON: Maschetah silt loam, grassland. (Colors are for dry soil unless otherwise noted)
A1--0 to 3 inches; grayish brown (10YR 5/2) silt loam, very dark grayish brown (10YR 3/2) moist; moderate fine granular structure; slightly hard, friable, slightly sticky and slightly plastic; many very fine roots; slightly alkaline; clear smooth boundary.
A2--3 to 6 inches; grayish brown (10YR 5/2) silt loam, very dark grayish brown (10YR 3/2) moist; weak very fine blocky structure; hard, friable, slightly sticky and plastic; common very fine roots; slightly effervescent; moderately alkaline; clear wavy boundary. (Combined A horizons 5 to 8 inches thick)
Bk1--6 to 13 inches; light brownish gray (2.5Y 6/2) silty clay loam, dark grayish brown (2.5Y 4/2) moist; moderate medium prismatic structure parting to moderate fine and medium blocks; hard, friable, sticky and plastic; common very fine roots; common very fine tubular pores; strongly effervescent; few fine masses of lime; moderately alkaline; clear wavy boundary.
Bk2--13 to 19 inches; light gray (2.5Y 7/2) silty clay loam, light olive brown (2.5Y 5/3) moist; weak medium prismatic structure parting to moderate fine and medium blocks; hard, friable, sticky and slightly plastic; common very fine roots; many very fine tubular pores; moderately effervescent; many fine and medium masses of lime; moderately alkaline; diffuse irregular boundary.
Bk3--19 to 30 inches; light gray (2.5Y 7/2) silt loam, light olive brown (2.5Y 5/3) moist; moderate coarse prismatic structure parting to weak coarse blocks; hard, friable, sticky and slightly plastic; few very fine roots; common very fine tubular pores; violently effervescent; common fine and medium masses of lime; moderately alkaline; gradual wavy boundary. (Combined Bk horizons 15 to 42 inches thick)
BCk--30 to 43 inches; pale yellow (2.5Y 7/3) silt loam, light olive brown (2.5Y 5/4) moist; weak coarse prismatic structure; hard, friable, slightly sticky and slightly plastic; few very fine roots; common very fine tubular pores; strongly effervescent; common fine masses of lime; moderately alkaline; gradual wavy boundary.
C--43 to 65 inches; pale yellow (2.5Y 7/3) silt loam, light olive brown (2.5Y 5/4) moist; massive; hard, friable, slightly sticky and slightly plastic; common very fine tubular pores; strongly effervescent; moderately alkaline.
TYPE LOCATION: Big Horn County, Montana; 600 feet north and 385 feet west of the SE corner of sec. 20, T. 5 S., R. 33 E.
RANGE IN CHARACTERISTICS:
Soil temperature - 44 to 47 degrees F.
Moisture control section - between 4 and 12 inches.
A calcareous Bw horizon up to 10 inches thick is allowed.
A horizons - Hue: 10YR, 2.5Y or 5Y
Value: 4 or 5 dry; 3 or 4 moist
Chroma: 2 or 3
Clay content: 20 to 27 percent
Reaction: pH 7.4 to 8.4
Bk horizons - Hue: 10YR, 2.5Y or 5Y
Value: 6 or 7 dry; 4 or 5 moist
Chroma: 2, 3 or 4
Texture, less than 2 mm: silt loam or silty clay loam
Clay content: 20 to 35 percent
Rock fragments: 0 to 5 percent pebbles
Calcium carbonate equivalent: 20 to 40 percent
Reaction: pH 7.9 to 8.4
C horizon - Hue: 10YR, 2.5Y or 5Y
Value: 6 or 7 dry; 4 or 5 moist
Chroma: 2, 3 or 4
Texture, less than 2 mm: silt loam or silty clay loam
Clay content: 20 to 35 percent
Rock fragments: 0 to 5 percent pebbles
Reaction: pH 7.9 to 8.4
COMPETING SERIES:
Chama - has paralithic beds at depths of 20 to 40 inches.
GEOGRAPHIC SETTING:
Landform - sedimentary plains and hills.
Elevation - 2,000 to 5,000 feet.
Parent material - calcareous silty eolian or alluvial deposits.
Slope- 0 to 45 percent.
Climate - long, cold winters; moist springs, warm summers.
Mean annual precipitation - 15 to 19 inches.
Mean annual air temperature - 40 to 45 degrees F.
Frost-free period - 90 to 125 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Cabba, Cherry, Lambert and Norbert series. These soils do not have a mollic epipedon. In addition, Cabba and Norbert soils are shallow to paralithic beds, and Cherry soils have a cambic horizon. Cabba soils occur on convex shoulder slopes above the Maschetah soils. Cherry and Lambert soils occur on similar positions to the Maschetah soils. Norbert soils occur below the Maschetah soils on the landscape.
DRAINAGE AND PERMEABILITY: Well drained; moderately slow permeability.
USE AND VEGETATION: Maschetah soils are used mainly for range and some for growing small grains. Potential native vegetation is mainly western wheatgrass, blue grama, bluegrass, needleandthread, and fringed sagewort.
DISTRIBUTION AND EXTENT: Maschetah soils are of small extent in south-central and southeastern Montana, and western North Dakota.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Denver, Colorado
SERIES ESTABLISHED: Big Horn County (Big Horn Area), Montana, 1970.
REMARKS: Soil Interpretations Record: MT0515. Diagnostic horizons and features recognized in this pedon are: a mollic epipedon from the soil surface to 7 inches mixed (A1, A2, Bk1 horizons); a calcic horizon from 6 to 43 inches (Bk1, Bk2, Bk3, BCk horizons); a particle-size control section from 10 to 40 inches (Bk1, Bk2, Bk3, BCk horizons). Maschetah soils have a frigid temperature regime and an Ustic moisture regime.