LOCATION CUNIFF MTEstablished Series
TAXONOMIC CLASS: Loamy, mixed, superactive, frigid, shallow Typic Haplustolls
TYPICAL PEDON: Cuniff fine sandy loam, rangeland (colors are for dry soil unless otherwise noted).
A--0 to 5 inches; dark grayish brown (10YR 4/2) fine sandy loam, very dark grayish brown (10YR 3/2) moist; weak very fine granular structure; soft, very friable, slightly sticky and slightly plastic; many very fine roots; slightly alkaline (pH 7.6); clear smooth boundary. (5 to 7 inches thick)
Bw--5 to 11 inches; light brownish gray (10YR 6/2) fine sandy loam, dark brown (10YR 4/3) moist; weak medium prismatic structure parting to weak medium and fine subangular blocky; soft, very friable, slightly sticky and slightly plastic; common very fine roots; many very fine tubular and interstitial pores; disseminated lime; strongly effervescent, moderately alkaline (pH 8.0); gradual smooth boundary. (5 to 10 inches thick)
Bk--11 to 16 inches; light brownish gray (2.5Y 6/2) fine sandy loam, grayish brown (2.5Y 5/2) moist; weak medium prismatic structure parting to weak medium and fine subangular blocky; soft, very friable, slightly sticky and nonplastic; common very fine roots; common very fine tubular and interstitial pores; 20 percent soft sandstone pebbles; continuous distinct coatings of lime on fragments; disseminated lime; strongly effervescent; moderately alkaline (pH 8.4); clear smooth boundary. (3 to 8 inches thick)
Cr--16 to 60 inches; light olive gray (5Y 6/2) semiconsolidated sedimentary beds; olive gray (5Y 5/2) moist; few fine roots between cracks in upper part; strongly effervescent; moderately alkaline (pH 8.4).
TYPE LOCATION: Lewis and Clark County, Montana; 2,100 feet north and 2,000 feet east of the SW corner of sec. 15, T. 19 N., R. 7 W.
RANGE IN CHARACTERISTICS:
Soil temperature - 42 to 47 degrees F.
Moisture control section - between 4 and 12 inches.
Depth to Cr horizon - 13 to 20 inches.
Depth to Bk horizon - 5 to 9 inches.
A horizon - Value: 4 or 5 dry
Chroma: 2 or 3
Clay content: 10 to 18 percent
Reaction: pH 6.6 to 7.8
Bw horizon - Value: 5 or 6 dry
Chroma: 2, 3, or 4
Clay content: 8 to 18 percent
Calcium carbonate equivalent: 0 to 5 percent
Reaction: pH 7.4 to 8.4
Bk horizon - Hue: 10YR or 2.5Y
Value: 6 or 7 dry, 4 or 5 moist
Chroma: 2 or 3
Clay content: 8 to 15 percent
Calcium carbonate equivalent: 5 to 10 percent
Reaction: pH 7.9 to 8.4
COMPETING SERIES:
Hackney (MT) - does not have horizon of secondary carbonate accumulation.
GEOGRAPHIC SETTING:
Landform - sedimentary plains, hills.
Elevation - 4,200 to 5,000 feet.
Slope - 2 to 35 percent.
Parent material - residuum from sandstone or in colluvium over the sandstone.
Climate - long, cold winters; moist springs; and warm summers.
Mean annual precipitation - 15 to 19 inches.
Mean annual temperature - 40 to 45 degrees F.
Frost-free period - 90 to 110 days.
DRAINAGE AND PERMEABILITY: Well drained; moderate permeability.
USE AND VEGETATION: Cuniff soils are used mainly for rangeland.
Potential native vegetation is mainly rough fescue, bluebunch wheatgrass, Idaho fescue, and prairie junegrass.
DISTRIBUTION AND EXTENT: Cuniff soils are inextensive in west central and southwestern Montana.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Bozeman, Montana
SERIES ESTABLISHED: Lewis and Clark County, Montana, 1991; proposed in Lewis and Clark County, Montana, 1987.
REMARKS: Soil interpretation record: MT1210. Diagnostic horizons and features recognized in this pedon are: a mollic epipedon from the surface to 7 inches (A, upper Bw horizons); a cambic horizon from 5 to 11 inches (Bw horizon); a particle-size control section from 10 inches to the paralithic contact (Bw, Bk horizons); and a paralithic contact at a depth of 16 inches (Cr horizon). Cuniff soils have a frigid temperature regime and an ustic moisture regime.