LOCATION FERNLINE MTEstablished Series
TAXONOMIC CLASS: Fine, mixed, active, frigid Andic Hapludalfs
TYPICAL PEDON: Fernline ashy silt loam, forested (colors are for dry soil unless otherwise noted).
Oi--0 to 2 inches; undecomposed and slightly decomposed forest litter. (1 to 2 inches thick)
A--2 to 3 inches; grayish brown (10YR 5/2) ashy silt loam, very dark grayish brown (10YR 3/2) moist; weak fine granular structure; soft, very friable, nonsticky and nonplastic; common very fine and fine roots; volcanic ash component; moderately acid (pH 6.0); clear wavy boundary. (0 to 3 inches thick)
Bw--3 to 11 inches; light yellowish brown (10YR 6/4) ashy silt loam, dark yellowish brown (10YR 4/4) moist; weak fine and medium subangular blocky structure parting to weak fine granular; soft, very friable, nonsticky and nonplastic; common very fine and fine roots; moderately acid (pH 6.0); clear wavy boundary. (7 to 11 inches thick)
2E--11 to 16 inches; very pale brown (10YR 7/3) silty clay loam, brown (10YR 5/3) moist; moderate medium subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; common very fine and fine roots; moderately acid (pH 6.0); gradual wavy boundary. (3 to 10 inches thick)
2Bt/E--16 to 23 inches; Bt part (60 percent) is pink (7.5YR 7/4) silty clay, brown (7.5YR 5/4) moist, E part (40 percent) is very pale brown (10YR 7/3) silty clay, brown (10YR 5/3) moist; moderate medium subangular blocky structure; hard, firm, sticky and plastic; common very fine and fine roots; few distinct clay films on faces of peds; strongly acid (pH 5.4); gradual wavy boundary. (4 to 11 inches thick)
2Bt--23 to 36 inches; pink (7.5YR 7/4) and pinkish white (7.5YR 8/2) silty clay, brown (7.5YR 5/4) and pinkish gray (7.5YR 6/2) moist; strong medium subangular blocky structure; hard, firm, sticky and plastic; common very fine and fine roots; common distinct clay films on faces of peds; strongly acid (pH 5.4); gradual wavy boundary. (10 to 24 inches thick)
2C--36 to 60 inches; pink (7.5YR 7/4) and pinkish white (7.5YR 8/2) silty clay, brown (7.5YR 5/4) and pinkish gray (7.5YR 6/2) moist; massive; hard, firm, sticky and plastic; common very fine and fine roots; few fine distinct mottles; neutral (pH 7.2).
TYPE LOCATION: Sanders County, Montana; 1,900 feet north and 500 feet west of the SE corner of sec. 33, T. 26 N., R. 32 W.
RANGE IN CHARACTERISTICS:
Soil temperature - 44 to 47 degrees F.
Moisture control section - between 8 and 24 inches.
A horizon - Value: 5, 6, or 7 dry, 3, 4, or 5 moist
Clay content: 8 to 15 percent
Bulk density: 0.85 to 1.00 g/cc
Acid Oxalate (Al + 1/2 Fe): 1.0 to 2.0 percent
Reaction: 5.6 to 6.5
Bw horizon - Value: 5, 6, or 7 dry; 4, 5, or 6 moist
Clay content: 8 to 15 percent
Bulk density: 0.85 to 1.00 g/cc
Acid Oxalate (Al + 1/2 Fe): 1.0 to 2.0 percent
Reaction: 5.6 to 6.5
2E horizon - Value: 6, 7, or 8 dry; 5, 6, or 7 moist
Clay content: 27 to 35 percent
Reaction: 5.1 to 6.5
2Bt/E horizon - Hue: 7.5YR or 10YR
Value: B part 6 or 7, E part 6 or 7 dry; B part 4 or 5, E part 5 or 6 moist
Chroma: E part 2 or 3
Clay content: 40 to 50 percent
Base saturation: 60 to 75 percent
Reaction: 5.1 to 6.5
2Bt horizon - Hue: 7.5YR, 10YR, or 5YR
Value: 5, 6, or 7 dry; 4, 5, or 6 moist
Clay content: 40 to 60 percent
Base saturation: 60 to 75 percent
Reaction: 5.1 to 6.5
2C horizon - Hue: 7.5YR, 10YR, or 5YR
Value: 5, 6, or 7 dry; 4, 5, or 6 moist
Clay content: 40 to 60 percent
Reaction: 5.1 to 7.3
COMPETING SERIES: There are no competing series.
GEOGRAPHIC SETTING:
Landform - lake plains or terraces in valleys.
Elevation - 2,200 to 2,800 feet.
Slope - 0 to 35 percent.
Parent material - volcanic ash over glaciolacustrine deposits.
Climate - long, cold winters; moist springs; warm summers.
Mean annual precipitation - 28 to 34 inches.
Mean annual air temperature - 42 to 45 degrees F.
Frost-free period - 90 to 105 days.
DRAINAGE AND PERMEABILITY: Well drained, very slow permeability.
USE AND VEGETATION: Fernline soils are used mainly for woodland, understory grazing, and wildlife habitat. Potential native vegetation is mainly Douglas fir, ponderosa pine, western larch, lodgepole pine, grand fir, western white pine, western red cedar, and western hemlock. Understory vegetation is mainly common snowberry, white spirea, oceanspray, twinflower, queencup beadlily, western goldthread, columbia brome, starry false solomonseal, trailplant, and other forbs and shrubs.
DISTRIBUTION AND EXTENT: Fernline 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: MT1381. Diagnostic horizons and features recognized in this pedon are: an ochric epipedon from the mineral soil surface to 7 inches, mixed (A, Bw horizons); an ash influenced layer from 2 to 11 inches (A, Bw horizons); an albic horizon from 11 to 16 inches (2E horizon); an argillic horizon from 16 to 36 inches (2Bt/E, 2Bt horizons); a particle-size control section from 16 to 36 inches (2Bt/E, 2Bt horizons). Fernline soils have a udic moisture regime and a frigid temperature regime.
ADDITIONAL DATA: Laboratory data S91MT-089-018.