LOCATION NYTHAR MTEstablished Series
TAXONOMIC CLASS: Fine-loamy, mixed, superactive, frigid Cumulic Endoaquolls
TYPICAL PEDON: Nythar silty clay loam, in pasture (colors are for moist colors unless otherwise noted).
Oi--0 to 2 inches; partially decomposed organic matter
A--2 to 16 inches; black (N 2/0) silty clay loam, black (N 2/0) dry; moderate medium granular structure; hard, friable, slightly sticky and slightly plastic; many very fine, fine and medium roots; common fine tubular pores; 5 percent cobbles, 5 percent pebbles; neutral (pH 7.0); gradual wavy boundary. (8 to 15 inches thick)
Bg1--16 to 25 inches; very dark gray (N 3/0) silty clay loam, gray (10YR 5/1) dry; moderate fine subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; many very fine, fine and medium roots; common fine and medium pores; 5 percent cobbles, 5 percent pebbles; neutral (pH 6.8); gradual wavy boundary.
Bg2--25 to 36 inches; very dark gray (5Y 3/1) silty clay loam, gray (N 5/0) dry; moderate medium subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; few very fine roots; common fine and medium pores; 5 percent cobbles, 5 percent pebbles; neutral (pH 6.8); gradual wavy boundary. (Combined thickness of Bg1 and Bg2 horizons is 15 to 25 inches)
Bg3--36 to 46 inches; dark grayish brown (2.5Y 4/2) silt loam, light gray (5Y 7/1) dry; many medium brownish yellow (10YR 6/6) redox concentrations; weak medium subangular blocky structure; hard, friable, slightly sticky and slightly plastic; few very fine roots; common fine pores; neutral (pH 7.0); gradual wavy boundary. (0 to 10 inches thick)
Cg--46 to 60 inches; light gray (2.5Y 7/2) cobbly silty clay loam, pale yellow (2.5Y 8/2) dry; many medium yellow (10YR 7/6) redox concentrations; massive; slightly hard, very friable, slightly sticky and slightly plastic; few very fine roots; common fine pores; 15 percent cobbles and 10 percent pebbles; neutral (pH 7.2).
TYPE LOCATION: Granite County, Montana; 700 feet east and 2350 feet north of the SW corner of sec. 28, T. 10 N., R. 13 W.
RANGE IN CHARACTERISTICS:
Soil temperature - 41 to 46 degrees F.
Moisture control section - between 4 and 12 inches.
Depth to seasonal high water table - 0 to 12 inches.
Mollic epipedon thickness - 24 to 60 inches.
A horizon
Hue: 2.5Y, 10YR or N
Value: 2, 3 or 4 dry; 2 or 3 moist
Chroma: 0, 1 or 2
Texture: silty clay loam, silt loam or loam
Clay content: 18 to 35 percent
Rock fragments: 0 to 15 percent--0 to 5 percent cobbles; 0 to 10 percent pebbles
Reaction: pH 6.6 to 7.8
Bg1 and Bg2 horizons
Hue: 2.5Y, 10YR, 5Y or N
Value: 4 or 5 dry; 2 or 3 moist
Chroma: 0, 1 or 2
Texture: silty clay loam, loam or silt loam
Clay content: 18 to 35 percent
Rock fragments: 0 to 35 percent--0 to 5 percent cobbles; 0 to 30 percent pebbles
Reaction: 6.6 to 7.3
Bg3 horizon - Hue: 2.5Y, 5Y or 10YR
Value: 4, 5, 6 or 7 dry, 2, 3 or 4 moist
Chroma: 1 or 2
Texture: silty clay loam, loam or silt loam
Clay content: 18 to 35 percent
Rock fragments: 0 to 35 percent--0 to 5 percent cobbles; 0 to 30 percent pebbles
Reaction: pH 6.6 to 7.3
Cg horizon - Hue: 2.5Y, 10YR or N
Value: 4, 5, 6, 7 or 8 dry, 2, 3, 4, 5, 6 or 7 moist
Chroma: 0, 1 or 2
Texture: silty clay loam, sandy clay loam, loam or sandy loam
Clay content: 18 to 35 percent
Rock fragments: 0 to 45 percent--0 to 15 percent cobbles; 0 to 30 percent pebbles
Reaction: 6.6 to 7.3
COMPETING SERIES:
Chamita (NM) - is poorly drained
Cometcrik (MT) - has a lithologic discontinuity at 40 to 60 inches.
Eagleton (MT) - does not have Bg horizons; is stratified throughout the particle-size control section; is poorly drained.
Kerkhoven (MN) - is poorly drained
Kovich (UT) - has a skeletal lithologic discontinuity in the particle-size control section.
Lakepark (MN) - has free carbonates at 25 to 50 inches.
Lobe (CO) - is poorly drained and has a lithologic discontinuity at depth of less than 60 inches.
Mannixlee (MT) - has a lithologic discontinuity at 40 to 60 inches.
Marshbrook (SD) - is poorly or somewhat poorly drained.
Marshdale - is poorly drained and has a lithologic discontinuity at depth of less than 60 inches.
Sibannac - has a lithologic discontinuity in the particle-size control section.
Welch (NV) - has a high component of vitric pyroclastic material in the particle-size control section.
GEOGRAPHIC SETTING:
Landform- glacial outwash plains, stream terraces, drainageways, alluvial fans and flood plains.
Elevation - 3600 to 6400 feet.
Slope - 0 to 6 percent.
Parent material - alluvium
Climate - long, cold winters; moist springs; warm summers.
Mean annual precipitation - 10 to 22 inches
Mean annual air temperature - 39 to 44 degrees F.
Frost-free period - 70 to 110 days.
GEOGRAPHICALLY ASSOCIATED SOILS:
DRAINAGE AND PERMEABILITY: Very poorly drained, moderate permeability.
USE AND VEGETATION: Nythar soils are primarily used for pasture and wildlife habitat. The potential native vegetation is mainly tall reedgrass, tufted hairgrass, blue-eye grass and willows.
DISTRIBUTION AND EXTENT: Nythar soils are inextensive in western Montana valleys.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Bozeman, Montana
SERIES ESTABLISHED: Gallatin County, Montana, 1997; series proposed: Granite County, Montana, 1995.
REMARKS: Soil interpretive record: MT1598. Diagnostic horizons and features recognized in this pedon are: a mollic epipedon from the top of the mineral layer to 36 inches (A, Bg1, Bg2 horizons; a cambic horizon from 36 to 46 inches (Bg3 horizon); a particle-size control section from 10 to 40 inches (A, Bg1, Bg2 and Bg3 horizons). Nythar soils have a frigid temperature regime and an aquic moisture regime.