LOCATION SCOTMONT MTEstablished Series
TAXONOMIC CLASS: Coarse-loamy, mixed, superactive, frigid Vitrandic Hapludalfs
TYPICAL PEDON: Scotmont ashy fine sandy loam, forested (colors are for dry soil unless otherwise noted).
Oi--0 to 1 inch; undecomposed and slightly decomposed forest litter. (1 to 2 inches thick)
A--1 to 8 inches; pale brown (10YR 6/3) ashy fine sandy loam, brown (10YR 4/3) moist, weak fine and medium subangular blocky structure; soft, very friable, nonsticky and nonplastic; many fine, medium, and coarse roots; moderately acid (pH 6.0); gradual wavy boundary. (3 to 7 inches thick)
E--8 to 15 inches; very pale brown (10YR 7/3) ashy fine sandy loam, brown (10YR 5/3) moist; moderate fine and medium subangular blocky structure; soft, very friable, nonsticky and nonplastic; many fine, medium, and coarse roots; moderately acid (pH 6.0); gradual wavy boundary. (6 to 20 inches thick)
E & Bt1--15 to 29 inches; E (90 percent) is very pale brown (10YR 7/3) fine sandy loam, brown (10YR 5/3) moist; massive; soft, very friable, nonsticky and nonplastic; common fine, medium, and coarse roots; Bt (10 percent) is very pale brown (10YR 7/4) 1/8- to 3/8-inch thick fine sandy loam lamellae, yellowish brown (10YR 5/4) moist; moderate medium subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; common clay films bridging sand grains; common fine, medium, and coarse roots; moderately acid (pH 6.0); gradual wavy boundary. (8 to 20 inches thick)
E & Bt2--29 to 44 inches; E (80 percent) is very pale brown (10YR 7/3) loamy very fine sand, brown (10YR 5/3) moist; massive; soft, very friable, nonsticky and nonplastic; common fine and medium, and few coarse roots; Bt (20 percent) is very pale brown (10YR 7/4) 3/8- to 1 1/2- inch thick very fine sandy loam lamellae, yellowish brown (10YR 5/4) moist; moderate medium subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; many clay films bridging sand grains; common fine and medium, and few coarse roots; slightly acid (pH 6.2); clear wavy boundary. (8 to 20 inches thick)
E & Bt3--44 to 60 inches; E (50 percent) is very pale brown (10YR 7/3) loamy fine sand, brown (10YR 5/3) moist; massive; soft, very friable, nonsticky and nonplastic; common medium and few coarse roots; Bt (50 percent) is very pale brown (10YR 7/4) 3/8- to 2-inch thick fine sandy loam lamellae, yellowish brown (10YR 5/4) moist; moderate medium subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; many clay films bridging sand grains; common medium and few coarse roots; slightly acid (pH 6.2).
TYPE LOCATION: Sanders County, Montana; 1,500 feet west and 800 feet south of the NE corner of sec. 6, T. 21 N., R. 29 W.
RANGE IN CHARACTERISTICS:
Soil temperature - 44 to 47 degrees F.
Moisture control section - between 8 and 24 inches.
A horizon - Value: 5 or 6 dry, 4 or 5 moist
Clay content: 4 to 10 percent
Bulk density: 1.0 to 1.40 g/cc
Acid oxalate (Al + 1/2 Fe): 0.4 to 1.0 percent
Reaction: 5.1 to 6.5
E horizon - Value: 6 or 7 dry, 5 or 6 moist
Clay content: 4 to 10 percent
Bulk density: 1.0 to 1.40 g/cc
Acid oxalate (Al + 1/2 Fe): 0.4 to 1.0 percent
Reaction: 5.1 to 6.5
E & Bt1 horizon - Value: E part 6 or 7, Bt part 5, 6 or 7 dry; E part 5 or 6, Bt part 4 or 5 moist
Clay content: E part 4 to 10 percent, Bt part 8 to 15 percent
Reaction: 5.6 to 6.5
E & Bt2 horizon - Value: E part 6 or 7, Bt part 5, 6 or 7 dry; E part 5 or 6, Bt part 4 or 5 moist
Clay content: E part 4 to 10 percent, Bt part 8 to 15 percent
Reaction: 5.6 to 6.5
E & Bt3 horizon - Value: E part 6 or 7, B part 5, 6 or 7 dry; E part 5 or 6, B part 4 or 5 moist
Clay content: E part 4 to 10 percent, Bt part 8 to 15 percent
Reaction: 5.6 to 6.5
COMPETING SERIES:
Lionwood (MT) - has a 2Bt horizon below 40 inches.
GEOGRAPHIC SETTING:
Landform - lake plains and terraces.
Elevation - 2,300 to 2,800 feet.
Slope - 0 to 35 percent.
Parent material - a component of volcanic ash in the surface layers and formed in glaciolacustrine deposits.
Climate - long, cold winters; moist springs; warm summers.
Mean annual precipitation - 24 to 28 inches.
Mean annual air temperature - 42 to 45 degrees F.
Frost-free period - 90 to 115 days.
DRAINAGE AND PERMEABILITY: Well drained, moderate permeability.
USE AND VEGETATION: Scotmont soils are used mainly for woodland, understory grazing, and wildlife habitat. Potential native vegetation is mainly Douglas fir, ponderosa pine, western larch, lodgepole pine, western white pine, and grand fir. Understory vegetation is mainly elk sedge, brackenfern, pinegrass, and other forbs and shrubs.
DISTRIBUTION AND EXTENT: Scotmont soils are of limited extent in the valleys of northwestern Montana.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Bozeman, Montana
SERIES ESTABLISHED: Sanders County, Montana, 1997.
REMARKS: Soil interpretation record: MT1384. Diagnostic horizons and features recognized in this pedon are: an ash influenced layer from 1 to 15 inches (A, E horizons); an ochric epipedon from the mineral soil surface to 7 inches (A horizon); an albic horizon from 8 to 15 inches (E horizon); an argillic horizon consisting of 3/8- to 2-inch lamellae totaling 6 inches or more in thickness between a depth of 44 and 60 inches (E & Bt3 horizon); a particle-size control section from 10 to 40 inches below the mineral soil surface (E, E & Bt1, E & Bt2 horizons). Scotmont soils have a udic moisture regime and a frigid temperature regime.