LOCATION HEWOLF MTEstablished Series
TAXONOMIC CLASS: Sandy-skeletal, mixed, frigid Fluventic Haploxerolls
TYPICAL PEDON: Hewolf gravelly loam, in irrigated grass pasture. (Colors are for dry soil unless otherwise noted)
Ap--0 to 7 inches; grayish brown (10YR 5/2) gravelly loam, very dark grayish brown (10YR 3/2) moist; moderate fine subangular blocky structure; soft, very friable, nonsticky and nonplastic; many very fine, fine and medium roots; 20 percent pebbles; neutral (pH 7.2); clear smooth boundary. (6 to 11 inches thick)
Bw--7 to 13 inches; light brownish gray (10YR 6/2) very gravelly sandy loam, dark grayish brown (10YR 4/2) moist; weak fine subangular blocky structure; soft, very friable, nonsticky and nonplastic; many very fine, fine and medium roots; 40 percent pebbles; neutral (pH 7.2); clear wavy boundary. (0 to 8 inches thick)
2C--13 to 60 inches; light brownish gray (10YR 6/2) extremely gravelly sand, dark grayish brown (10YR 4/2) moist; single grain; loose, nonsticky and nonplastic; few very fine roots; 60 percent pebbles; neutral. (pH 7.0)
TYPE LOCATION: Sanders County, Montana; 700 feet south and 1500 feet east of the northwest corner of sec. 27, T. 18 N., R. 21 W.
RANGE IN CHARACTERISTICS:
Soil temperature - 43 to 47 degrees F.
Moisture control section - between 12 and 35 inches.
Mollic epipedon thickness - 7 to 11 inches. The soil when mixed to a depth of 7 inches meets the requirements of a mollic epipedon. Unmixed areas have an erratic carbon distribution.
Depth to seasonal high water table - 60 to 72 inches.
Control section - 0 to 6 percent clay and 35 to 75 percent rock fragments.
A horizon - Value: 4 or 5 dry; 2 or 3 moist
Chroma: 1, 2 or 3
Clay content: 8 to 15 percent
Rock fragments: 15 to 35 percent - 0 to 5 percent cobbles; 15 to 30 percent pebbles
Reaction: pH 6.6 to 7.3
Bw horizon - Value: 5 or 6 dry; 4 or 5 moist
Chroma: 2 or 3
Texture: sandy loam, fine sandy loam
Clay content: 5 to 15 percent
Rock fragments: 35 to 60 percent - 0 to 10 percent cobbles; 35 to 50 percent pebbles
Reaction: pH 6.6 to 7.3
2C- Value: 6 or 7 dry; 4, 5 or 6 moist
Chroma: 2 or 3
Texture: sand or loamy sand
Clay content: 0 to 5 percent
Rock fragments: 45 to 75 percent - 0 to 10 percent cobbles; 45 to 65 percent pebbles
Reaction: pH 6.6 to 7.3
COMPETING SERIES:
Mippon (WA) - have mollic colors to a depth of 60 inches; do not have a cambic horizon.
Smout (ID) - have a mollic epipedon 11 to 18 inches thick; do not have a cambic horizon.
GEOGRAPHIC SETTING:
Landform - low stream terraces in mountain valleys.
Elevation - 2500 to 2900 feet.
Slope- 0 to 2 percent.
Parent material - alluvium.
Climate - long cold winters, moist springs, warm, dry summers.
Mean annual precipitation - 14 to 18 inches, much of which falls as snow and spring rains.
Mean annual temperature - 41 to 45 degrees F.
Frost-free period - 90 to 110 days.
DRAINAGE AND PERMEABILITY: Moderately well drained; moderately rapid over rapid permeability.
USE AND VEGETATION: These soils are used as irrigated and dryland pasture and cropland, and wildlife habitat. The potential native vegetation is mainly mid and short grasses with riparian shrubs.
DISTRIBUTION AND EXTENT: These soils are of limited extent in northwestern Montana mountain valleys.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Bozeman, Montana
SERIES ESTABLISHED: Sanders County, Montana, 1997.
REMARKS: Soil Interpretation record: MT1175. Diagnostic horizons and features recognized in this pedon are: a mollic epipedon from the surface to 7 inches (Ap horizon); a cambic horizon from 7 to 13 inches (Bw horizon); a particle size control section from 10 to 40 inches (Bw and 2C horizons); Hewolf soils have a frigid temperature regime and a Xeric moisture regime.