LOCATION NEWTMAN MT
Established Series
Rev. GAR-KTS-RJS
05/2011
NEWTMAN SERIES
The Newtman series consists of very deep, very poorly drained soils that formed in alluvium. These soils are on flood plains, stream terraces, depressions and marshes. Slopes are 0 to 4 percent. Mean annual precipitation is about 14 inches, and the mean annual air temperature is about 42 degrees F.
TAXONOMIC CLASS: Fine-loamy, mixed, superactive, calcareous, frigid Histic Humaquepts
TYPICAL PEDON: Newtman mucky peat, in pasture (colors are for moist soil unless otherwise noted).
Oe--0 to 9 inches; black (10YR 2/1) mucky peat, very dark gray (10YR 3/1) dry; few fine prominent strong brown (7.5YR 5/8) redox concentrations; weak fine granular structure; soft, very friable, nonsticky and nonplastic; strongly effervescent; moderately alkaline (pH 8.2); clear smooth boundary. (8 to 16 inches thick)
A--9 to 15 inches; black (10YR 2/1) silty clay loam, very dark gray (10YR 3/1) dry; weak medium subangular blocky structure parting to moderate fine granular; very hard, firm, moderately sticky and moderately plastic; common very fine and fine roots; slightly effervescent; slightly alkaline (pH 7.8); clear wavy boundary. (0 to 9 inches thick)
Cg--15 to 24 inches; gray (5Y 5/1) silty clay loam, gray (5Y 6/1) dry; massive; very hard, very firm, moderately sticky and moderately plastic; common very fine and fine roots; 5 percent gravel, 5 percent cobbles; slightly effervescent; moderately alkaline (pH 8.4); clear smooth boundary. (8 to 24 inches thick)
2Cg--24 to 60 inches; dark gray (5Y 4/1) very gravelly sandy clay loam, light brownish gray (10YR 6/2) dry; massive; hard, firm, slightly sticky and slightly plastic; 40 percent gravel, 10 percent cobbles; slightly effervescent, moderately alkaline (pH 8.0).
TYPE LOCATION: Gallatin County, Montana; 1400 feet south and 1900 feet west of the northeast corner of sec. 15, T. 1N, R. 4E.
RANGE IN CHARACTERISTICS:
Mean annual soil temperature - 39 to 43 degrees F.
Histic epipedon thickness - 8 to 16 inches
Depth to lithologic discontinuity - 22 to 36 inches
Depth to seasonal high water table - ponded to 12 inches
Oe horizon
Hue: 10YR or N; dry or moist
Value: 2 to 6 dry; 2 to 4 moist
Chroma: 1 or 2; dry or moist
Reaction: pH 7.4 to 8.4
A horizon
Hue: 10YR or N; dry or moist
Value: 3 to 6 dry; 2 to 4 moist
Chroma: 0 to 2; dry or moist
Texture: silt loam or silty clay loam
Clay content: 20 to 35 percent
Rock fragments: 0 to 5 percent gravel
Calcium carbonate equivalent: 2 to 15 percent
Reaction: pH 7.4 to 8.4
Cg horizon
Hue: 5Y, 2.5Y, 5BG, 5GY or N; dry or moist
Value: 4 to 7 dry; 2 to 6 moist
Chroma: 0 to 2; dry or moist
Texture: silty clay loam, silt loam, loam or clay loam
Clay content: 20 to 35 percent
Rock fragments: 0 to 10 percent--0 to 5 percent gravel, 0 to 5 percent cobbles
Calcium carbonate equivalent: 2 to 15 percent
Reaction: pH 7.9 to 8.4
2Cg horizon
Hue: 10YR, 5Y, 2.5Y or N; dry or moist
Value: 4 to 6 dry; 2 to 5 moist
Chroma: 1 or 2; dry or moist
Texture: sandy clay loam, sandy loam, clay loam or loam
Clay content: 18 to 30 percent
Rock fragments: 15 to 60 percent--10 to 45 percent gravel, 0 to 15 percent cobbles
Calcium carbonate equivalent: 1 to 10 percent
Reaction: pH 7.4 to 8.4
COMPETING SERIES: There are no competing series.
GEOGRAPHIC SETTING:
Landform - floodplains, stream terraces, depressions and marshes
Elevation - 4,100 to 6,300 feet
Slope - 0 to 4 percent
Parent material - mixed alluvium
Climate - long cold winters; moist springs; warm summers
Mean annual precipitation - 10 to 18 inches
Mean annual air temperature - 37 to 43 degrees F.
Frost-free period - 70 to 110 days
GEOGRAPHICALLY ASSOCIATED SOILS: None listed.
DRAINAGE AND PERMEABILITY: Very poorly drained; moderately slow permeability.
USE AND VEGETATION: Newtman soils are used mainly for pasture and wildlife habitat. Potential native vegetation may include tall reedgrasses, tall sedges and rushes, American sloughgrass, iris, willows, waterbirch, dogwood and silver buffaloberry as well as other grasses, sedges, forbs and shrubs.
DISTRIBUTION AND EXTENT: Newtman soils are of small extent in southwestern Montana. MLRA - 44B.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Bozeman, Montana.
SERIES ESTABLISHED: Gallatin County, Montana, 1997.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
Histic epipedon - from 0 to 9 inches (Oa horizon)
Particle-size control section - from 19 to 49 inches (part of A, Cg, part of 2Cg horizons)
Newtman soils have a frigid temperature regime and an aquic moisture regime.
ADDITIONAL DATA: Soil interpretation record - MT1639.
National Cooperative Soil Survey
U.S.A.