LOCATION STARGULCH MTEstablished Series
TAXONOMIC CLASS: Coarse-loamy, mixed, superactive, frigid Andic Hapludalfs
TYPICAL PEDON: Stargulch ashy very fine sandy loam, forested (colors are for moist soil unless otherwise noted).
Oi--0 to 2 inches; undecomposed and slightly decomposed forest litter. (1 to 3 inches thick)
A--2 to 4 inches; dark brown (10YR 3/3) ashy very fine sandy loam, brown (10YR 5/3) dry; weak fine granular structure; soft, very friable, nonsticky and nonplastic; many very fine, fine, and medium and common coarse roots; moderately acid (pH 5.8); clear wavy boundary. (1 to 3 inches thick)
Bw1--4 to 10 inches; dark yellowish brown (10YR 4/4) ashy very fine sandy loam, yellowish brown (10YR 5/6) dry; weak fine and medium subangular blocky structure; soft, very friable, nonsticky and nonplastic; many very fine, fine, and medium and common coarse roots; moderately acid (pH 5.8); clear wavy boundary. (4 to 8 inches thick)
Bw2--10 to 15 inches; dark yellowish brown (10YR 4/4) ashy very fine sandy loam, brownish yellow (10YR 6/6) dry; weak medium subangular blocky structure; soft, very friable, nonsticky and nonplastic; many very fine and fine and common medium and coarse roots; moderately acid (pH 5.8); clear wavy boundary. (4 to 8 inches thick)
2E and Bt1--15 to 27 inches; E part (90 percent) is brown (10YR 5/3) loamy fine sand, pale brown (10YR 6/3) dry, Bt part (10 percent) is dark yellowish brown (10YR 4/4) fine sandy loam lamellae, 1/4 to 3/8 inch thick, light yellowish brown (10YR 6/4) dry; moderate medium subangular blocky structure; soft, very friable, nonsticky and nonplastic; common fine, medium, and coarse roots; moderately acid (pH 5.8); gradual wavy boundary. (8 to 16 inches thick)
2E and Bt2--27 to 46 inches; E part (70 percent) is brown (10YR 5/3) loamy fine sand, pale brown (10YR 6/3) dry; massive; soft, very friable, nonsticky and nonplastic; common fine and medium, and few coarse roots; moderately acid (pH 5.8); Bt part (30 percent) is dark yellowish brown (10YR 4/4) 1 to 2 inch thick fine sandy loam lamellae, light yellowish brown (10YR 6/4) dry; 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; moderately acid (pH 6.0); gradual wavy boundary. (12 to 24 inches thick)
2Bt and E--46 to 60 inches; Bt part (60 percent) is dark yellowish brown (10YR 4/4) 1 to 2 inch thick very fine sandy loam lamellae, light yellowish brown (10YR 6/4) dry; moderate medium subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; many clay films bridging sand grains; few fine, medium, and coarse roots; moderately acid (pH 6.0); E part (70 percent) is brown (10YR 5/3) loamy fine sand, pale brown (10YR 6/3) dry; massive; soft, very friable, nonsticky and nonplastic; few fine, medium, and coarse roots; moderately acid (pH 5.8).
TYPE LOCATION: Sanders County, Montana; 1200 feet north and 1800 feet west of the southeast corner of section 27, T. 27 N., R. 34 W.
RANGE IN CHARACTERISTICS:
Soil temperature - 44 to 47 degrees F.
Moisture control section - between 8 and 24 inches
A horizon - Value: 4, 5, or 6 dry, 3, 4, or 5 moist
Clay content: 0 to 6 percent
Bulk density: 0.85 to 1.0 g/cc
Acid oxalate extractable Al + 1/2 Fe: 1.0 to 1.5 percent
Reaction: 5.1 to 6.5
Bw horizons - Value: 5 or 6 dry, 4 or 5 moist
Clay content: 0 to 6 percent
Bulk density: 0.85 to 1.0 g/cc
Acid oxalate extractable Al + 1/2 Fe: 1.0 to 2.0 percent
Reaction: 5.1 to 6.5
2E and Bt1 horizon - Value: 5 or 6 dry, 4 or 5 moist
Clay content: E part 0 to 6 percent, Bt part 8 to 12 percent
Reaction: 5.6 to 6.5
2E and Bt2 horizon - Value: 5 or 6 dry, 4 or 5 moist
Clay content: E part 0 to 6 percent, Bt part 8 to 12 percent5
Reaction: 5.6 to 6.5
2Bt and E horizon - Value: 5 or 6, 4 or 5 moist
Clay content: Bt part 8 to 15 percent, E part 4 to 10 percent
Reaction: 5.6 to 6.5
COMPETING SERIES:
Mushel (ID) - does not have horizons containing lamellae.
GEOGRAPHIC SETTING:
Landform - stream terraces in valleys.
Elevation - 2200 to 2600 feet.
Slope - 0 to 15 percent.
Parent material - volcanic ash over alluvium or outwash.
Climate - long, cold winters; moist springs;warm summers.
Mean annual precipitation - 30 to 34 inches.
Mean annual temperature - 42 to 45 degrees F.
Frost-free period - 90 to 105 days.
DRAINAGE AND PERMEABILITY: Well drained, moderate permeability.
USE AND VEGETATION: Stargulch soils are used mainly for woodland, understory grazing, and wildlife habitat. Potential native vegetation is mainly western redcedar, western hemlock, western white pine, grand fir, western larch, Douglas fir, and ponderosa pine. Understory vegetation is mainly trailing blackberry, thinleaf alder, oceanspray, white spirea, brackenfern, western goldthread, trailplant, queencup beadlily, bunchberry dogwood, twinflower, sweetscented bedstraw, pinegrass, and other shrubs, forbs, and grasses.
DISTRIBUTION AND EXTENT: Stargulch soils are of small 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: MT1516. Diagnostic horizons and features recognized in this pedon are: an ash influenced layer from 2 to 15 inches (A, Bw1, Bw2 horizons); an ochric epipedon from 2 to 9 inches mixed (A, Bw1 horizons); an argillic horizon consisting of 1 to 2 inch lamellae totaling 6 inches or more in thickness between a depth of 27 and 60 inches (2E and Bt, 2Bt and E horizons); a particle size control section from 27 to 60 inches (2E and Bt2, 2Bt and E horizons). Stargulch soils have a udic moisture regime and a frigid temperature regime.
ADDITIONAL DATA: NSSL data S93MT-089-001.