LOCATION NIEMAN MTEstablished Series
TAXONOMIC CLASS: Loamy-skeletal, mixed, superactive Lithic Argicryolls
TYPICAL PEDON: Nieman very cobbly loam, very stony, in rangeland (colors are for dry soil unless otherwise noted).
A--0 to 4 inches; brown (10YR 4/3) very cobbly loam, dark brown (10YR 3/3) moist; moderate medium granular structure; slightly hard, friable, slightly sticky and slightly plastic; many very fine and fine roots; many very fine and fine interstitial pores; 20 percent cobbles, 25 percent gravel; neutral (pH 6.8); clear wavy boundary. (4 to 7 inches thick)
Bt1--4 to 8 inches; dark grayish brown (10YR 4/2) very cobbly loam, very dark grayish brown (10YR 3/2) moist; moderate fine and medium subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; many very fine and fine roots; many very fine and fine interstitial pores; common faint brown (10YR 4/3) clay films on faces of peds; 25 percent cobbles, 30 percent gravel; neutral (pH 7.0); clear wavy boundary.
Bt2--8 to 13 inches; dark grayish brown (10YR 4/2) extremely cobbly loam, dark grayish brown (10YR 4/2) moist; moderate fine and medium subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; common very fine and many fine roots; many very fine and fine interstitial pores; common distinct clay films on faces of peds; 35 percent cobbles, 35 percent gravel, neutral (pH 7.0). (Combined thickness of Bt horizons is 6 to 12 inches)
R--13 inches; hard fine grained igneous bedrock.
TYPE LOCATION: Jefferson County, Montana; 700 feet north and 75 feet east of the SW corner of sec. 18, T. 3 N., R. 4 W.
RANGE IN CHARACTERISTICS:
Soil temperature - 35 to 42 degrees F.
Moisture control section - between 4 and 12 inches, or between 4 inches and the lithic contact if bedrock is at less than 12 inches.
Mollic epipedon thickness - 7 to 12 inches, includes all or part of the Bt horizon.
Depth to argillic horizon - 4 to 7 inches.
Depth to bedrock - 10 to 20 inches.
Surface stones or boulders - 0 to 15 percent
Some pedons have a BC and/or C horizon
A horizon - Hue: 2.5Y or 10YR
Value: 3 to 5 dry; 2 or 3 moist
Chroma: 2 or 3
Clay content: 10 to 27 percent
Rock fragments: 10 to 60 percent--0 to 25 percent cobbles, 10 to 35 percent gravel
Reaction: pH 6.6 to 7.3
Bt horizons - Hue: 7.5YRm 10YR, 2.5Y, or 5Y
Value: 4 to 6 dry; 3 to 5 moist
Chroma: 2, 3, or 4
Texture: loam, sandy loam, sandy clay loam or clay loam
Clay content: 18 to 30 percent
Rock fragments: 35 to 80 percent--0 to 35 percent cobbles, 30 to 55 percent gravel
Reaction: pH 6.0 to 7.8
COMPETING SERIES:
Bushpark (CO) - has a udic moisture regime.
Copenhaver (MT) - has hues redder than 10YR in the argillic horizon.
Donkehill (ID) - has a horizon of secondary carbonate accumulation; formed in calcareous materials.
Hogmalat (ID) - is strongly to moderately acid throughout; formed in materials derived from welded tuff.
Layview (NV) - has a mean annual soil temperature greater than 42 degrees; is dry 90 or more consecutive days (July 15 through October 15) in the moisture control section; formed in andesite, rhyolite, and tuff.
Maygal (NV) - has a xeric moisture regime.
Mosroc (WY) - has a moisture control section that is dry between four-tenths and five-tenths of the year cumulative; has 10 to 14 inches of precipitation.
Mountpatterson (CA) has a xeric moisture regime.
Nielsen (ID) - has rock fragments that are channer size in the argillic horizon.
Notstew (NV) has a xeric moisture regime.
Thiefridge (CA) has a xeric moisture regime.
GEOGRAPHIC SETTING:
Landform - escarpments, ridges, strath terraces, cuestas and sideslopes of hills and mountains.
Elevation - 5,500 to 8,500 feet.
Slope - 2 to 70 percent.
Parent material - fine grained sandstone; fine grained igneous rock.
Climate - long, cold winters; cool, moist springs; short, cool summers.
Mean annual precipitation - 14 to 24 inches.
Mean annual air temperature - 34 to 40 degrees F.
Frost-free period - 30 to 70 days.
GEOGRAPHICALLY ASSOCIATED SOILS: This is the Libeg soil. Libeg soils are very deep and are on less convex positions.
DRAINAGE AND PERMEABILITY: Well drained, moderate permeability.
USE AND VEGETATION: Nieman soils are primarily used for rangeland, woodland, and wildlife habitat. The potential native vegetation is mainly rough fescue, Idaho fescue, sandberg bluegrass, lupine, bluebunch wheatgrass, prairie Junegrass, Western yarrow, hoods phlox, and big sagebrush. Areas in woodland have an overstory of Douglas fir and an understory of rough fescue, Idaho fescue, bluebunch wheatgrass, sandberg bluegrass, Rocky Mountain juniper, and big sagebrush.
DISTRIBUTION AND EXTENT: Nieman soils are of moderate extent in southwestern Montana.
MLRA OFFICE RESPONSIBLE: Bozeman, Montana
SERIES ESTABLISHED: Jefferson County, Montana, 1998.
REMARKS: Soil interpretation record: MT3053, MT3054. Diagnostic horizons and features recognized in this pedon are: a mollic epipedon from the soil surface to 8 inches (A, Bt horizons); an argillic horizon from 4 to 13 inches (Bt1, Bt2 horizons); a particle-size control section from the soil surface to 13 inches (A, Bt1, Bt2 horizons); hard fine grained igneous bedrock at a depth of 13 inches (R horizon). Nieman soils have a cryic temperature regime and an ustic moisture regime.