LOCATION HOGHEAVEN MTEstablished Series
TAXONOMIC CLASS: Coarse-silty, mixed, superactive, frigid Aquic Haploxerolls
TYPICAL PEDON: Hogheaven silt loam, pasture. (Colors are for dry soils unless otherwise noted.)
Apn1--0 to 2 inches; dark grayish brown (10YR 4/2) silt loam, very dark brown (10YR 2/2) moist; moderate very fine granular structure; soft, very friable, slightly sticky and slightly plastic; many very fine and fine and common medium roots; slightly effervescent; moderately alkaline (pH 8.2); clear smooth boundary. (0 to 3 inches thick)
Apn2--2 to 8 inches; dark grayish brown (10YR 4/2) silt loam, very dark brown (10YR 2/2) moist; moderate medium subangular blocky structure; slightly hard, very friable, slightly sticky and slightly plastic; common very fine and fine roots; common fine tubular pores; slightly effervescent; moderately alkaline (pH 8.4); clear smooth boundary. (5 to 9 inches thick)
Bkn1--8 to 15 inches; grayish brown (10YR 5/2) silt loam, very dark grayish brown (10YR 3/2) moist; moderate fine subangular blocky structure; slightly hard, very friable, sticky and slightly plastic; common very fine and fine roots; common very fine and fine pores; disseminated lime; violently effervescent; strongly alkaline (pH 8.6); clear smooth boundary. (5 to 15 inches thick)
Bkn2--15 to 21 inches; light gray (10YR 7/2) silt loam, grayish brown, (10YR 5/2) moist; weak coarse subangular blocky structure; soft, very friable, nonsticky and nonplastic, few very fine and fine roots; few fine pores; disseminated lime; strongly effervescent; strongly alkaline (pH 8.6); gradual smooth boundary. (4 to 10 inches thick)
C1--21 to 42 inches; white (10YR 8/2) silt loam, brown (10YR 5/3) moist; few faint yellowish brown (10YR 5/8) redox concentrations; massive; soft, very friable, nonsticky and nonplastic; few fine and very fine roots; moderately alkaline (pH 8.0); gradual smooth boundary. (10 to 30 inches thick)
C2--42 to 60 inches; white (10YR 8/2) silt loam, pale brown (10YR 6/3) moist; common faint yellowish brown (10YR 5/8) redox concentrations; massive; soft, very friable, nonsticky and nonplastic; moderately alkaline (pH 8.2).
TYPE LOCATION: Sanders County, Montana; 1,250 feet west, 2,800 feet south of the NE corner of sec. 13, T. 24 N., R. 23 W.
RANGE IN CHARACTERISTICS:
Soil temperature - 43 to 45 degrees F.
Moisture control section - between 4 and 12 inches.
Mollic epipedon thickness - 7 to 16 inches.
Control section - 5 to 18 percent clay.
Depth to Bkn horizon: 5 to 12 inches.
Depth to seasonal high water table - 24 to 42 inches.
A horizons: Value: 4 or 5 dry; 2 or 3 moist
Chroma: 1 or 2
Clay content: 10 to 18 percent
EC: 2 to 4 mmhos/cm
SAR: 13 to 40
Calcium Carbonate equivalent: 3 to 10 percent
Reaction: pH 7.9 to 9.0
Thin surface layer may have SAR from 10 to 13
Bkn horizons - Value: 5, 6 or 7 dry; 3, 4 or 5 moist
Chroma: 2, 3 or 4
Texture: silt loam, silt
Clay content: 5 to 18 percent
Calcium Carbonate equivalent: 3 to 15 percent
EC: 1 to 3 mmhos/cm
SAR: 10 to 20
Reaction: pH 7.9 to 9.0
C horizons - Value: 6, 7 or 8 dry; 4, 5 or 6 moist
Chroma: 2, 3 or 4
Texture: silt loam, very fine sandy loam, silt
Clay content: 5 to 18 percent
EC: 0 to 1 mmhos/cm
SAR: 5 to 13
Reaction: 7.9 to 8.4
COMPETING SERIES: There are no competing series.
GEOGRAPHIC SETTING:
Landform - flood plains.
Slope- 0 to 2 percent.
Elevation - 2,700 to 3,000 feet.
Parent material - alluvium.
Climate - long, cold winters; moist springs; warm, dry summers.
Mean annual precipitation - 12 to 14 inches, much of which falls as snow and spring rains.
Mean annual temperature - 41 to 43 degrees F.
Frost-free period - 105 to 120 days.
DRAINAGE AND PERMEABILITY: Somewhat poorly drained, moderate permeability.
USE AND VEGETATION: Hogheaven soils are used for rangeland, pasture and hayland. The principle crop is grass hay. Native vegetation is dominated by basin wildrye and Nuttall alkaligrass.
DISTRIBUTION AND EXTENT: Hogheaven soils are of limited extent in the intermountain valleys of northwestern Montana.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Bozeman, Montana
SERIES ESTABLISHED: Sanders County, Montana, 1997.
REMARKS: Soil interpretation record MT1220. Diagnostic horizons and features recognized in this pedon are: a mollic epipedon from 0 to 15 inches (Apn1, Apn2 and Bkn1 horizons); accumulation of lime from 8 to 21 inches (Bkn1 and Bkn2 horizons); accumulation of sodium from the soil surface to 21 inches (Apn1, Apn2, Bkn1 and Bkn2 horizons); faint redox concentrations from 21 ot 60 inches (C1 and C2 horizons); a particle size control section from 10 to 40 inches (Bkn1, Bkn2 and C1 horizons). Hogheaven soils have a frigid temperature regime and an aridic moisture regime bordering on xeric.