LOCATION HAUZ MTEstablished Series
TAXONOMIC CLASS: Loamy-skeletal, mixed, superactive, frigid Aridic Argiustolls
TYPICAL PEDON: Hauz channery loam, grassland (colors are for dry soil unless otherwise noted).
A--0 to 5 inches; brown (7.5YR 5/2) channery loam, dark brown (7.5YR 3/2) moist; moderate very thin platy structure parting to moderate very fine granular; slightly hard, friable, moderately sticky and slightly plastic; many very fine roots; 25 percent channers; slightly acid (pH 6.4); clear smooth boundary. (4 to 6 inches thick)
Bt--5 to 15 inches; brown (7.5YR 5/4) very channery clay loam, reddish brown (5YR 4/3) moist; moderate medium prismatic structure parting to moderate very fine subangular blocky; hard, friable, moderately sticky and moderately plastic; common very fine roots; many very fine tubular and interstitial pores; many distinct clay films on faces of peds and on surface of fragments; 45 percent channers; neutral (pH 6.8); gradual smooth boundary. (6 to 17 inches thick)
BC--15 to 24 inches; brown (7.5YR 5/4) extremely channery loam, reddish brown (5YR 4/3) moist; weak medium and fine subangular blocky structure; slightly hard, very friable, moderately sticky and slightly plastic; common very fine roots; few faint clay films on faces of peds; 70 percent channers; neutral (pH 6.8); gradual smooth boundary. (10 to 20 inches thick)
R--24 inches; hard fractured bedrock; few fine roots extending into vertical cracks in upper part; few faint lime coatings on undersides of some fragments.
TYPE LOCATION: Lewis and Clark County, Montana; 1,200 feet south and 1,400 feet east of the NE corner of sec. 3, T. 12 N., R.5 W.
RANGE IN CHARACTERISTICS:
Soil temperature - 42 to 47 degrees F.
Moisture control section - between 4 and 12 inches.
Depth to bedrock - 20 to 40 inches.
Control section - 27 to 35 percent clay and less than 35 percent fine and coarser sand.
A horizon - Hue: 5YR, 7.5YR, or 10YR
Chroma: 2 or 3
Clay content: 15 to 25 percent
Rock fragments: 15 to 35 percent--0 to 5 percent flagstones, 15 to 30 percent channers
Reaction: pH 6.1 to 7.8
Bt horizon - Hue: 5YR, 7.5YR, or 10YR
Value: 5 or 6 dry, 3 or 4 moist
Chroma: 3 or 4
Clay content: 27 to 35 percent
Rock fragments: 50 to 85 percent--5 to 15 percent flagstones, 45 to 70 percent channers
Reaction: pH 6.1 to 7.8
The upper 1 to 3 inches of the Bt horizon has values of 5 dry, 3 moist, and chroma of 2 or 3.
BC horizon - Hue: 5YR through 10YR
Value: 5 or 6 dry, 4 or 5 moist
Chroma: 2, 3, or 4
Clay content: 10 to 25 percent
Rock fragments: 60 to 80 percent--10 to 20 percent flagstones, 50 to 60 percent channers
Reaction: pH 6.6 to 7.8
COMPETING SERIES:
Badito (CO) - moderately deep to a paralithic contact of tuff underlain by hard sandstone at depths between 40 and 60 inches.
Boyle (CO) - has a paralithic contact of weathered granite at 10 to 20 inches.
Ironco (UT) - is very deep.
San Isabel (CO) - do not have bedrock above a depth of 40 inches.
Simmont (WY) - have more than 35 percent fine and coarser sand in the control section.
Zillman (WY) - do not have bedrock above a depth of 40 inches.
GEOGRAPHIC SETTING:
Landform - hills and mountains.
Elevation - 4,000 to 5,500 feet.
Slope - 8 to 45 percent.
Parent material - material derived from igneous and argillite rock.
Climate - long, cold winters; moist springs; warm summers.
Mean annual precipitation - 10 to 14 inches.
Mean annual temperature - 40 to 45 degrees F.
Frost-free period - 105 to 120 days.
DRAINAGE AND PERMEABILITY: Well drained; moderate permeability.
USE AND VEGETATION: Hauz soils are used mainly for rangeland. Native vegetation is mainly bluebunch wheatgrass, needleandthread, prairie junegrass, western wheatgrass, fringed sagewort, and silver sage.
DISTRIBUTION AND EXTENT: Hauz soils are moderately extensive in southwestern Montana.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Bozeman, Montana
SERIES ESTABLISHED: Lewis and Clark County Area, Montana, 1991; proposed in Lewis and Clark County, Montana, 1979.
REMARKS: Soil interpretations record: MT0378. Diagnostic horizons and features recognized in this pedon are: a mollic epipedon from the surface to 7 inches mixed (A horizon); an argillic horizon and particle-size control section from 5 to 15 inches (Bt horizon); a lithic contact at 24 inches (R horizon). Hauz soils have a frigid temperature regime and an ustic moisture regime that borders on aridic.