LOCATION BLAINE MT+CO WYEstablished Series
TAXONOMIC CLASS: Loamy-skeletal, mixed, superactive Ustic Argicryolls
TYPICAL PEDON: Blaine gravelly loam, rangeland (colors are for dry soil unless otherwise noted).
A--0 to 4 inches; grayish brown (10YR 5/2) gravelly loam, very dark grayish brown (10YR 3/2) moist; moderate fine granular structure; slightly hard, very friable, slightly sticky and slightly plastic; many fine and very fine roots; 35 percent pebbles; slightly alkaline (pH 7.4); clear smooth boundary. (3 to 6 inches thick)
Bt--4 to 10 inches; brown (10YR 4/3) very gravelly clay loam, dark brown (10YR 3/3) moist; moderate medium prismatic structure parting to moderate fine blocky; hard, friable, moderately sticky and moderately plastic; common fine and very fine roots; common distinct clay films on faces of peds and on coarse fragments; 35 percent pebbles and 5 percent cobbles; slightly alkaline (pH 7.4); clear wavy boundary. (4 to 14 inches thick)
Bk1--10 to 16 inches; light gray (2.5Y 7/2) very gravelly loam, grayish brown (2.5Y 5/2) moist; weak medium prismatic structure parting to moderate fine blocky; slightly hard, very friable, slightly sticky and slightly plastic; common fine and very fine roots; 30 percent pebbles and 15 percent cobbles; many films and soft masses of calcium carbonate and limecasts on undersides of fragments; violently effervescent; clear wavy boundary.
Bk2--16 to 24 inches; light olive gray (5Y 6/2) very gravelly loam, olive (5Y 4/3) moist; massive; slightly hard, very friable, slightly sticky and slightly plastic; few very fine roots; 35 percent pebbles and 15 percent cobbles; few soft masses of calcium carbonate and many thin limecasts on undersides of fragments; strongly effervescent; abrupt wavy boundary.
R--24 inches; fractured igneous bedrock.
TYPE LOCATION: Broadwater County Area, Montana; 1,200 feet south and 600 feet west of the center of sec. 10, T. 5 N., R. 1 W.
RANGE IN CHARACTERISTICS:
Soil temperature - 38 to 42 degrees F.
Moisture control section - between 4 and 12 inches.
Mollic epipedon thickness - 7 to 15 inches.
Depth to bedrock - 20 to 40 inches.
Some pedons have a Cr horizon above the R horizon at 20 to 40 inches.
A horizon - Hue: 10YR or 2.5Y
Value: 4 or 5 dry; 2 or 3 moist
Chroma: 1, 2, or 3
Texture: loam, sandy clay loam or sandy loam
Clay content: 5 to 27 percent
Rock fragments: 0 to 80 percent--0 to 45 percent cobbles and stones; 0 to 50 percent pebbles
Reaction: pH 6.1 to 7.8
Bt horizon - Hue: 10YR or 2.5Y
Value: 4, 5 or 6 dry; 2, 3, 4 or 5 moist
Chroma: 2, 3 or 4
Texture: loam, clay loam or sandy clay loam
Clay content: 22 to 35 percent
Rock fragments: 35 to 70 percent--5 to 30 percent cobbles and stones; 25 to 55 percent pebbles
Reaction: pH 6.6 to 7.8
Bk horizons - Hue: 10YR through 5Y
Value: 5, 6, 7, or 8 dry; 4, 5, or 6 moist
Chroma: 2, 3, or 4
Texture: loam, sandy loam, fine sandy loam, silt loam or sandy clay loam
Clay content: 10 to 25 percent
Rock fragments: 35 to 80 percent--10 to 35 percent cobbles and stones; 25 to 60 percent pebbles
Calcium carbonate equivalent: 5 to 15 percent
Reaction: pH 7.4 to 8.4
COMPETING SERIES:
Bowen (CO) - does not have horizons of secondary carbonate accumulation.
Fourmile (CO) - is very deep; does not have horizons of secondary carbonate accumulation.
Fornor (WY) - is very deep; formed in glacial drift.
Geertsen (UT) - is deep; does not have horizons of secondary carbonate accumulation.
Hodden (CO) - is very deep.
Hoodle (UT) - is very deep.
Lagarita (CO) - is very deep.
Libeg (MT) - is very deep; does not have horizons of secondary carbonate accumulation.
Maciver (MT) - is very deep.
Nathale (WY) - has more than 35 percent fine or coarser sand in the Bt horizon; formed in interbedded limestone and sandstone.
Nathrop (CO) - has a BA horizon; formed in residuum from limestone.
Norriston (CO) - is very deep; does not have horizons of secondary carbonate accumulation; has a lithologic discontinuity at 10 to 20 inches.
Parkview (CO) - has a paralithic contact at 20 to 40 inches; does not have horizons of secondary carbonate accumulation.
Quander (CO) - is deep or very deep; does not have horizons of secondary carbonate accumulation.
Ratiopeak (MT) - is very deep.
Spanpeak (MT) - is very deep; has an O horizon.
Teeler (WY) - is very deep.
Woodhall (CO) - does not have horizons of secondary carbonate accumulation.
GEOGRAPHIC SETTING:
Landform - hills, ridges, cuestas and mountains.
Elevation - 4,000 to 7,500 feet.
Slope - 0 to 60 percent.
Parent material - Colluvium and residuum from igneous rock or hard shale and sandstone.
Climate - long cold winters, cool, moist springs; short summers.
Mean annual precipitation - 15 to 19 inches.
Mean annual temperature is 36 to 45 degrees F.
Frost-free period - 30 to 70 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Cheadle and Rootel soils. Cheadle soils are shallow to a lithic contact. Rootel soils have a calcic horizon and do not have a mollic epipedon.
DRAINAGE AND PERMEABILITY: Well drained; moderate permeability.
USE AND VEGETATION: Blaine soils are used mainly for rangeland. Potential native vegetation is mainly bluebunch wheatgrass, Idaho fescue, needleandthread, blue grama, forbs, and shrubs.
DISTRIBUTION AND EXTENT: Blaine soils are of moderate extent in central and southwestern Montana.
MLRA OFFICE RESPONSIBLE: Bozeman, Montana
SERIES ESTABLISHED: Northern plains of Montana (Reconnaissance), 1929.
REMARKS: Soil Interpretations Records: MT0051, MT0501, and MT9052. Diagnostic horizons and features recognized in this pedon are: a mollic epipedon from the soil surface to 10 inches (A, Bt horizons); an argillic horizon from 4 to 10 inches (Bt horizon); horizons of secondary carbonate accumulation from 10 to 24 inches (Bk horizons); a lithic contact at 24 inches (R horizon); and a particle-size control section from 4 to 24 inches (Bt, Bk1, Bk2 horizons). Blaine soils have a cryic temperature regime and an ustic moisture regime.