LOCATION SHEAFMAN MT
Established Series
Rev. EMR/JMS/RJS
07/2013
SHEAFMAN SERIES
The Sheafman series consists of very deep, excessively drained soils that formed in coarse gravelly outwash or colluvium derived from igneous rock. These soils are on outwash fans and escarpments. Slopes are 1 to 35 percent. Mean annual precipitation is about 368 mm and mean annual air temperature is about 6.0 degrees C.
TAXONOMIC CLASS: Sandy-skeletal, mixed, frigid Typic Haplustolls
TYPICAL PEDON: Sheafman gravelly coarse sandy loam, in rangeland on a 2 percent slope at 1,036 meters elevation (colors are for dry soil unless otherwise indicated).
A--0 to 20 cm; grayish brown (10YR 5/2) gravelly coarse sandy loam, very dark grayish brown (10YR 3/2) moist; moderate medium granular structure; very friable, soft, nonsticky and nonplastic; many fine and common medium roots; many fine irregular and interstitial pores; 20 percent gravel; neutral (pH 6.8); clear smooth boundary. (18 to 33 cm thick)
Bw--20 to 36 cm; pale brown (10YR 6/3) gravelly coarse sandy loam, brown (10YR 4/3) moist; moderate fine subangular blocky structure; very friable, soft, nonsticky and nonplastic; common fine and medium roots; many fine interstitial pores; 30 percent gravel; neutral (pH 6.8); clear smooth boundary. (15 to 43 cm thick)
C1--36 to 76 cm; pale brown (10YR 6/3) very gravelly loamy coarse sand, brown (10YR 4/3) moist; single grain; loose, nonsticky and nonplastic; very few fine roots; common fine interstitial pores; 45 percent gravel, 10 percent cobbles; neutral (pH 7.0); gradual wavy boundary.
C2--76 to 152 cm; pale brown (10YR 6/3) extremely gravelly coarse sand, brown (10YR 4/3) moist; single grain; loose, nonsticky and nonplastic; few fine roots; common fine interstitial pores; 55 percent gravel, 10 percent cobbles; neutral (pH 7.0).
TYPE LOCATION: Victor topographic quadrangle, Ravalli County, Montana; 20 meters south and 265 meters west of the NE corner of section 31, T. 8 N., R. 20 W. UTM Zone 11: 719871e, 5144039n, NAD 83.
RANGE IN CHARACTERISTICS:
Mean annual soil temperature - 5.0 to 8.0 degrees C
Mollic epipedon thickness - 18 to 33 cm
A horizon
Value: 4 or 5 dry; 3 or 2 moist
Chroma: 2 or 3; dry or moist
Texture: coarse sandy loam, sandy loam or loam
Clay content: 8 to 18 percent
Rock fragments: 5 to 35 percent - 5 to 35 percent gravel, 0 to 20 percent cobbles, 0 to 5 percent stones
Reaction: pH 5.6 to 7.5
Bw horizon
Value: 6 or 7 dry; 3 or 4 moist
Chroma: 2 or 3; dry or moist
Texture: coarse sandy loam or sandy loam
Clay content: 5 to 18 percent
Rock fragments: 15 to 60 percent--15 to 50 percent gravel, 0 to 20 percent cobbles
Reaction: pH 5.6 to 7.3
C horizon(s)
Value: 6 or 7 dry; 4 or 5 moist
Chroma: 2 to 4; dry or moist
Texture: loamy coarse sand, coarse sand, or loamy sand
Clay content: 0 to 10 percent
Rock fragments: 35 to 80 percent--15 to 70 percent gravel, 0 to 35 percent cobbles and stones
Reaction: pH 5.1 to 7.3
COMPETING SERIES:
Holman (NM) - do not have a cambic horizon
Lone Rock (CO) - do not have a cambic horizon
Wheelbarrow (MT) - are moderately deep to a paralithic and lithic
GEOGRAPHIC SETTING:
Landform - outwash fans and escarpments
Elevation - 975 to 1,300 meters
Slope - 1 to 35 percent
Parent material - outwash and colluvium derived from igneous rock
Climate - long, cold winters; moist springs; warm summers
Mean annual precipitation - 330 to 435 millimeters, much of which falls as snow and as spring rain
Mean annual air temperature - 4.0 to 7.0 degrees C
Frost-free period - 80 to 105 days
GEOGRAPHICALLY ASSOCIATED SOILS: None listed.
DRAINAGE AND PERMEABILITY: Excessively drained; moderate permeability to a depth of 36 cm, rapid and very rapid below.
USE AND VEGETATION: Sheafman soils are mainly used for irrigated pasture and hayland, or for dry-land pasture.
DISTRIBUTION AND EXTENT: Sheafman soils are of small extent in the valleys of western Montana. MLRA - 44A.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Bozeman, Montana.
SERIES ESTABLISHED: Bitterroot Valley Area, Montana, 2013; proposed in Ravalli County, Montana, 2006.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
Mollic epipedon - from 0 to 20 cm (A horizon)
Cambic horizon - from 20 to 36 cm (Bw horizon)
Particle-size control section - from 25 to 100 cm (part of the Bw, C1, and part of the C2 horizons)
Sheafman soils have a frigid temperature regime and an ustic moisture regime.
National Cooperative Soil Survey
U.S.A.