LOCATION MUSSIGBROD MTEstablished Series
TAXONOMIC CLASS: Fine-loamy, mixed, superactive Cumulic Haplocryolls
TYPICAL PEDON: Mussigbrod loam, in rangeland (colors are for dry soil unless otherwise noted).
A1--0 to 3 inches; dark grayish brown (10YR 4/2) loam, very dark brown (10YR 2/2) moist; weak medium and fine platy structure; soft, very friable, slightly sticky and non-plastic; many very fine and fine and common medium roots; many very fine and fine interstitial pores; 5 percent gravel; neutral (pH 7.0); clear smooth boundary.
A2--3 to 8 inches; brown (10YR 4/3) loam, very dark grayish brown (10YR 3/2) moist; moderate medium and fine subangular blocky structure; slightly hard, very friable, slightly sticky and non-plastic; many very fine and fine and few medium roots; many very fine and fine tubular pores; 5 percent gravel; very slightly effervescent; neutral (pH 7.2); clear wavy boundary.
A3--8 to 17 inches; grayish brown (10YR 5/2) loam, dark brown (10YR 3/3) moist; moderate medium and fine subangular blocky structure; slightly hard, very friable, slightly sticky and non-plastic; common very fine and fine and few medium roots; many very fine and fine tubular pores; 5 percent gravel; slightly effervescent; slightly alkaline (pH 7.5); gradual wavy boundary. (Combined thickness of A horizons is 16 to 24 inches thick)
Bk--17 to 27 inches; pale brown (10YR 6/3) loam, brown (10YR 4/3) moist; moderate medium subangular blocky structure; slightly hard, very friable, slightly sticky and non-plastic; few very fine, fine and medium roots; common medium pores; many soft masses of lime and coatings on rock fragments; 10 percent gravel; strongly effervescent; slightly alkaline (pH 7.8); gradual wavy boundary. (10 to 40 inches thick)
Ab--27 to 38 inches; brown (10YR 5/3) loam, dark brown (10YR 3/3) moist; weak medium subangular blocky structure parting to moderate medium and fine granular; soft, very friable, slightly sticky and non-plastic; few very fine roots; many very fine tubular pores; 5 percent gravel; slightly effervescent; slightly alkaline (pH 7.6); gradual wavy boundary. (0 to15 inches thick)
Bwb--38 to 49 inches; light yellowish brown (10YR 6/4) loam, brown (10YR 4/3) moist; weak medium and fine subangular blocky structure parting to weak fine and very fine granular; hard, friable, slightly sticky and slightly plastic; few very fine roots; few very fine tubular pores; 5 percent gravel; slightly alkaline (pH 7.6); gradual wavy boundary. (0 to 15 inches thick)
2C--49 to 60 inches; very pale brown (10YR 7/4) extremely gravelly sand, dark yellowish brown (10YR 4/4) moist; single grain; loose, non-sticky and non-plastic; 65 percent gravel; neutral (pH 7.1)
TYPE LOCATION: Beaverhead County, Montana; approximately 500 feet north and 1500 feet west of the SE corner of sec. 15, T 2 S, R 16 W; USGS Gibbons School, Montana topographic quadrangle; North American Datum 83, zone 12T, UTM 300519E, 5058898N.
RANGE IN CHARACTERISTICS:
Mean annual soil temperature - 35 to 40 degrees F., Cryic temperature regime.
Mean summer soil temperature - 53 to 57 degrees F.
Soil moisture control section - between 4 and 12 inches; dry in some or all parts for 90 or more cumulative days in normal years; not dry in all parts for more than half of the cumulative days. Ustic moisture regime.
Mollic epipedon thickness - 16 to 40 inches.
Depth to Bk horizon or secondary CaCO3 accumulation - 10 to 30 inches.
Some pedons have a Bw horizon above the Bk.
Some pedons are effervescent to the surface.
A horizons Hue: 10YR
Value: 3, 4 or 5 dry; 2 or 3 moist
Chroma: 1, 2 or 3
Texture: loam, silt loam or fine sandy loam
Clay content: 15 to 25 percent
Rock fragments: 0 to 35 percent gravel
Calcium Carbonate Equivalent: 0 to 10 percent
Reaction: pH 6.6 to 7.6
Bk horizon - Hue: 10YR
Value: 5, 6 or 7 dry; 3, 4 or 5 moist
Chroma: 3 or 4
Texture: loam, fine sandy loam or sandy clay loam
Clay content: 18 to 27 percent
Rock fragments: 0 to 35 percent gravel
Calcium Carbonate Equivalent: 5 to 15 percent
Reaction: pH 7.6 to 8.4
Ab horizon - Hue: 10YR
Value: 4 or 5 dry; 3 or 4 moist
Chroma: 2, 3 or 4
Texture: loam, fine sandy loam or sandy clay loam
Clay content: 15 to 25 percent
Rock fragments: 0 to 35 percent gravel
Calcium Carbonate Equivalent: 0 to 10 percent
Reaction: pH 6.6 to 8.0
Bwb horizon - Hue: 10YR
Value: 4, 5, 6 dry; 3, 4 or 5 moist
Chroma: 2, 3 or 4
Texture: loam, fine sandy loam or sandy clay loam
Clay content: 18 to 27 percent
Rock fragments: 0 to 35 percent gravel
Calcium Carbonate Equivalent: 0 to 10 percent
Reaction: pH 6.6 to 8.0
2C horizon - Hue: 7.5YR or 10YR
Value: 5, 6 or 7 dry; 4, 5 or 6 moist
Chroma: 4 or 6
Texture: sand, loamy sand or sandy loam
Clay content: 0 to 15 percent
Rock fragments: 25 to 75 percent--0 to 10 percent cobbles, 25 to 65 percent gravel
Reaction: pH 6.6 to 7.6
COMPETING SERIES:
Adderton - does not have horizon of carbonate accumulation; has a udic bordering on ustic moisture regime.
Lanswick - does not have a lithologic discontinuity; has a aridic ustic moisture regime.
Middlecreek - does not have horizon of carbonate accumulation; has a udic bordering on ustic moisture regime.
Silas - does not have horizon of carbonate accumulation; is moderately well drained.
GEOGRAPHIC SETTING:
Landform - Remnant outwash terraces and alluvial fans
Elevation - 5,900 to 6,600 feet
Slope - 0 to 15 percent.
Parent material - mixed alluvium.
Climate - long, cold winters; cool, moist springs; short, cool summers.
Mean annual precipitation - 14 to 19 inches.
Mean annual air temperature - 34 to 39 degrees F.
Frost-free period - 30 to 50 days
GEOGRAPHICALLY ASSOCIATED SOILS:
These are the Philipsburg and Briston soils. Philipsburg soils have an argillic and calcic horizon and are on alluvial fans. The Briston soils have an argillic horizon and lack a mollic epipedon and are on the same landform in the micro low position.
DRAINAGE AND PERMEABILITY: Well drained, moderate permeability.
USE AND VEGETATION: Mussigbrod soils are used for rangeland grazing and as wildlife habitat. The vegetation is mainly Idaho fescue, bluebunch wheatgrass, basin wildrye, mountain big sagebrush, and other miscellaneous grasses and forbs.
DISTRIBUTION AND EXTENT: Mussigbrod soils are not extensive in the intermountain valleys of southwestern Montana. MLRA 44.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Bozeman, Montana
SERIES ESTABLISHED: Beaverhead County, Montana, Big Hole Valley Area, 2005.
REMARKS: Diagnostic horizons and features recognized in this pedon are: a mollic epipedon from 0 to 17 inches (A1, A2 and A3 horizons); an accumulation of secondary calcium carbonates from 17 to 27 inches (Bk horizon); buried horizons from 27 to 49 inches (Ab and Bwb horizons); a lithologic discontinuity at 49 inches (2C horizon); a particle-size control section from 10 to 40 inches. Mussigbrod soils have a cryic temperature regime and an ustic moisture regime.
ADDITIONAL DATA: National Soil Survey Laboratory Data S03MT-001-006