LOCATION HACKNEY MTEstablished Series
TAXONOMIC CLASS: Loamy, mixed, superactive, frigid, shallow Typic Haplustolls
TYPICAL PEDON: Hackney loam, in rangeland (colors are for dry soil unless otherwise noted).
A1--0 to 3 inches; dark gray (10YR 4/1) loam, very dark gray (10YR 3/1) moist; moderate fine granular structure; soft, friable, slightly sticky and slightly plastic, many very fine and fine roots; many very fine tubular pores; neutral (pH 6.8); clear smooth boundary. (2 to 4 inches thick)
A2--3 to 8 inches; dark gray (10YR 4/1) clay loam, very dark gray (10YR 3/1) moist; moderate medium subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; many very fine and fine roots; many very fine and fine tubular pores; neutral (pH 7.0); clear smooth boundary. (0 to 8 inches thick)
Bw--8 to 13 inches; dark grayish brown (2.5Y 4/2) clay loam, very dark grayish brown (2.5Y 3/2) moist; moderate coarse subangular blocky structure; hard, firm, moderately sticky and moderately plastic; many very fine roots; many very fine tubular pores; neutral (pH 7.0); clear smooth boundary. (5 to 7 inches thick.)
Cr--13 to 60 inches; semiconsolidated shale.
TYPE LOCATION: Granite County, Montana; 1,900 feet east and 1,600 feet north of the SW corner of sec. 34, T. 11 N., R. 12 W.
RANGE IN CHARACTERISTICS:
Soil temperature - 41 to 47 degrees F.
Moisture control section - between 4 and 12 inches.
Mollic epipedon thickness - 7 to 15 inches.
Depth to Cr horizon - 10 to 20 inches.
A1 horizon - Value: 4 or 5 dry, 3 or 4 moist
Chroma: 1, 2, or 3
Clay content: 18 to 27 percent
Reaction: pH 6.6 to 7.3
A2 horizon - Value: 4 or 5 dry
Chroma: 1 or 2
Texture: loam or clay loam
Clay content: 18 to 30 percent
Reaction: pH 6.6 to 7.3
Bw horizon - Value: 4 or 5 dry, 3 or 4 moist
Chroma: 1 or 2
Clay content: 27 to 35 percent
Reaction: pH 6.6 to 7.3
COMPETING SERIES:
Cuniff (MT) - has horizons of secondary carbonate accumulation.
GEOGRAPHIC SETTING:
Landform - sedimentary plains and hills.
Elevation - 3,600 to 6,000 feet.
Slope- 4 to 50 percent.
Parent material - material derived from semiconsolidated shale.
Climate - long, cold winters; moist springs; warm summers.
Mean annual precipitation - 15 to 19 inches.
Mean annual air temperature - 39 to 45 degrees F.
Frost free period - 70 to 90 days.
DRAINAGE AND PERMEABILITY: Well drained, moderate permeability.
USE AND VEGETATION: Hackney soils are used mainly for rangeland. Native vegetation is western wheatgrass, bluebunch wheatgrass, Idaho fescue, antelope bitterbrush, lupine, woods rose, prairie junegrass, and rough fescue.
DISTRIBUTION AND EXTENT: Hackney soils are of small extent in southwestern Montana.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Bozeman, Montana
SERIES ESTABLISHED: Granite County, Montana, 1997.
REMARKS: Soil interpretation record: MT1402. Diagnostic horizons and features recognized in this pedon are: a mollic epipedon from the soil surface to 13 inches (A1, A2, Bw horizons); a paralithic contact at a depth of 13 inches. Hackney soils have a frigid temperature regime and an ustic moisture regime.