LOCATION NEEN MT
Established Series
Rev. GFB-KTS-RJS
05/2011
NEEN SERIES
The Neen series consists of very deep, somewhat poorly drained, saline soils that formed in alluvium. These soils are on flood plains, stream terraces and drainageways. Slopes are 0 to 4 percent. Mean annual precipitation is about 12 inches, and mean annual air temperature is about 43 degrees F.
TAXONOMIC CLASS: Fine-silty, mixed, superactive, frigid Aridic Calciustepts
TYPICAL PEDON: Neen silty clay loam, native grassland (colors are for dry soil unless otherwise noted).
Az1--0 to 2 inches; grayish brown (10YR 5/2) silty clay loam, dark grayish brown (10YR 4/2) moist; moderate fine and medium granular structure; slightly hard, friable, moderately sticky and moderately plastic; few very fine and fine roots; many very fine interstitial pores; many very fine salt crystals; finely disseminated calcium carbonate; violently effervescent; moderately alkaline (pH 8.0); abrupt smooth boundary. (1 to 3 inches thick)
Az2--2 to 9 inches; gray (10YR 6/1) silty clay loam, dark gray (10YR 4/1) moist; weak very fine and fine granular structure; slightly hard, friable, moderately sticky and moderately plastic; many very fine roots; many very fine interstitial pores; many very fine salt crystals; finely disseminated calcium carbonate; strongly effervescent; moderately alkaline (pH 8.0); abrupt wavy boundary. (5 to 10 inches thick)
Bkz1--9 to 32 inches; light gray (10YR 7/2) silty clay loam, grayish brown (10YR 5/2) moist; moderate fine granular structure; slightly hard, friable, moderately sticky and moderately plastic; few very fine roots; common very fine continuous tubular pores; many very fine salt crystals; finely disseminated calcium carbonate and few fine soft masses of calcium carbonate; violently effervescent; moderately alkaline (pH 8.0); clear smooth boundary. (15 to 30 inches thick)
Bkz2--32 to 50 inches; light gray (10YR 7/2) silty clay loam, grayish brown (10YR 5/2) moist; few fine prominent yellowish red (5YR 5/8) redox concentrations; moderate fine and medium subangular blocky structure; slightly hard, friable, moderately sticky and moderately plastic; few very fine roots; common very fine continuous tubular pores; few very fine salt crystals; finely disseminated calcium carbonate and common fine soft masses of calcium carbonate; violently effervescent; moderately alkaline (pH 8.0); clear smooth boundary. (15 to 20 inches thick)
Bkzg--50 to 60 inches; light gray (5Y 7/2) silty clay loam, olive gray (5Y 5/2) moist; common fine prominent yellowish red (5YR 4/6) redox concentrations; massive; hard, firm, moderately sticky and moderately plastic; many very fine roots; many very fine interstitial pores; few very fine salt crystals; finely disseminated calcium carbonate and few fine soft masses of calcium carbonate; strongly effervescent; moderately alkaline (pH 8.0).
TYPE LOCATION: Madison County, Montana; 2,140 feet west and 1,940 feet north of the SE corner of sec. 25, T. 4S, R. 7W.
RANGE IN CHARACTERISTICS:
Soil temperature - 40 to 44 degrees F.
Depth to a seasonally high water table - 24 to 50 inches (dominantly 30 to 45 inches)
Particle-size control section (weighted average) - less than 15 percent by weight fine sand or coarser (includes gravel) and more than 18 percent clay
Soil phases - drained and wet
Note: Some pedons may have an O, Bz and/or Bkg horizon. Also, some pedons may have a 2Cg horizon (lithologic discontinuity) at depths greater than 100 cm below the surface.
Az1 horizon
Hue: 10YR or 2.5Y; dry or moist
Value: 5 to 7 dry; 2 to 4 moist
Chroma: 1 or 2; dry or moist
Texture: silty clay loam, silt loam or loam
Clay content: 18 to 35 percent
Calcium carbonate equivalent: 1 to 15 percent
Sodium adsorption ratio: 13 to 30
Electrical conductivity: 0 to 10 mmhos/cm; drained phase--2 to 16 mmhos/cm
Reaction: pH 7.4 to 9.0
Az2 horizon
Hue: 10YR or 2.5Y; dry or moist
Value: 5 to 7 dry, 2 to 4 moist
Chroma: 1 or 2; dry or moist
Texture: silty clay loam or silt loam
Clay content: 18 to 35 percent
Calcium carbonate equivalent: 2 to 15 percent
Sodium adsorption ratio: 13 to 30
Electrical conductivity: 0 to 10 mmhos/cm; drained phase--2 to 16 mmhos/cm
Reaction: pH 7.4 to 9.0
Bkz1 horizon
Hue: 2.5Y or 5Y; dry or moist
Value: 6 to 8 dry; 5 to 7 moist
Chroma: 1 or 2; dry or moist
Redox concentrations: none to few
Texture: silty clay loam or silt loam
Clay content: 18 to 35 percent
Calcium carbonate equivalent: 20 to 40 percent
Sodium adsorption ratio: 13 to 30
Electrical conductivity: 2 to 10 mmhos/cm; drained phase--2 to 16 mmhos/cm
Reaction: pH 7.4 to 9.0
Bkz2 horizon
Hue: 2.5Y or 5Y; dry or moist
Value: 6 to 8 dry; 5 to 7 moist
Chroma: 1 or 2; dry or moist
Redox concentrations: few to many
Texture: silty clay loam, silt loam or fine sandy loam
Clay content: 18 to 35 percent
Calcium carbonate equivalent: 15 to 40 percent
Sodium adsorption ratio: 13 to 30
Electrical conductivity: 2 to 10 mmhos/cm; drained phase--2 to 16 mmhos/cm
Reaction: pH 7.4 to 9.0
Bkzg horizon
Hue: 10YR, 2.5Y, 5Y or 5GY; dry or moist
Value: 6 to 8 dry; 3 to 6 moist
Chroma: 1 or 2; dry or moist
Redox concentrations: few to many
Texture: silty clay loam, clay loam, loam or silt loam
Clay content: 18 to 35 percent
Sodium adsorption ratio: 5 to 30
Electrical conductivity: 4 to 8 mmhos/cm; drained phase--2 to 16 mmhos/cm
Calcium carbonate equivalent: 15 to 35 percent
Reaction: pH 7.4 to 9.0
2Cg horizon (where present)
Hue: 2.5Y, 5Y or 5GY; dry or moist
Value: 6 to 8 dry; 3 to 6 moist
Chroma: 1 or 2; dry or moist
Redox concentrations: few to many
Texture: loamy sand or sandy loam
Clay content: 5 to 12 percent
Rock fragments: 35 to 70 percent gravel
Sodium adsorption ratio: 0 to 5
Electrical conductivity: 0 to 4 mmhos/cm
Calcium carbonate equivalent: 2 to 15 percent
Reaction: pH 7.8 to 8.4
COMPETING SERIES:
Brockway (MT) - does not have horizons of salt accumulation
Cambeth (MT) - are moderately deep to a paralithic contact
GEOGRAPHIC SETTING:
Landform - flood plains, stream terraces and drainageways
Elevation - 3,600 to 6,500 feet
Slope - 0 to 4 percent
Parent material - alluvium
Climate - cool with long, cold winters; moist springs; warm summers
Mean annual precipitation - 10 to 14 inches
Mean annual air temperature - 38 to 43 degrees F.
Frost-free period - 70 to 120 days
GEOGRAPHICALLY ASSOCIATED SOILS: None listed.
DRAINAGE AND PERMEABILITY: Somewhat poorly drained; moderately slow permeability.
USE AND VEGETATION: These soils are used for irrigated hay, pasture, small grains, and as rangeland. The potential native vegetation is mainly western wheatgrass, basin wildrye, alkali sacaton, inland saltgrass, silver buffaloberry, and greasewood.
DISTRIBUTION AND EXTENT: Southwestern Montana. Neen soils are not extensive. MLRAs - 43B, 44B.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Bozeman, Montana.
SERIES ESTABLISHED: Madison County, Montana, 1983; proposed in Madison County, Montana 1978.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
Accumulation of salts - from 0 to 60 inches (Az1, Az2, Bkz1, Bkz2, Bkzg horizons)
Calcic horizon - from 9 to 60 inches (Bkz1, Bkz2, Bkzg horizons)
Redox concentrations - from 32 to 60 inches (Bkz2, Bkzg horizons)
Particle-size control section - from 10 to 40 inches (part of Bkz1, part of Bkz2 horizons)
Neen soils have a frigid temperature regime and an ustic moisture regime bordering on aridic.
ADDITIONAL DATA: Soil interpretation records - MT0396, MT0387, MT0668
National Cooperative Soil Survey
U.S.A.