LOCATION FOXGULCH MT

Established Series
Rev: PEM-KTS-RJS
04/2011

FOXGULCH SERIES

The Foxgulch series consists of very deep, somewhat poorly drained soils that formed in mixed alluvium on floodplains, drainageways, swales and outwash plains. These soils are subject to prolonged saturation due to flood irrigation. Slopes are 0 to 4 percent. Mean annual precipitation is about 16 inches, and mean annual air temperature is about 37 degrees F.

TAXONOMIC CLASS: Fine-loamy over sandy or sandy-skeletal, mixed, superactive Fluvaquentic Haplocryolls

TYPICAL PEDON: Foxgulch silt loam, in irrigated grass pasture (colors are for dry soil unless otherwise noted).

Oi--0 to 1 inch; undecomposed and partially decomposed matted roots; abrupt smooth boundary. (1 to 3 inches thick)

A1--1 to 11 inches; dark grayish brown (10YR 4/2) silt loam, very dark gray (10YR 3/1) moist; weak fine and medium subangular blocky structure parting to weak very fine and fine granular; soft, very friable, slightly sticky and slightly plastic; many very fine and few fine roots; many very fine and fine dendritic tubular pores; 5 percent mica flakes; neutral (pH 6.7); clear wavy boundary.

A2--11 to 16 inches; very dark gray (10YR 3/1) silty clay loam, black (10YR 2/1) moist; strong fine and medium subangular blocky structure; hard, firm, moderately sticky and moderately plastic; common very fine and few fine roots; many very fine and fine dendritic tubular pores; 5 percent mica flakes; slightly alkaline (pH 7.5); clear wavy boundary. (combined thickness of A1 and A2 horizons - 7 to 16 inches)

Bw--16 to 29 inches; light brownish gray (10YR 6/2) silt loam, dark grayish brown (10YR 4/2) moist; common threads and masses of dark grayish brown (10YR 4/2) silt loam, very dark gray (10YR 3/1) moist; strong medium and coarse subangular blocky structure; hard, friable, slightly sticky and slightly plastic; common very fine and few fine roots; common very fine and few fine dendritic tubular pores; 10 percent mica flakes; slightly alkaline (pH 7.6); clear wavy boundary. (10 to 20 inches thick)

BC--29 to 36 inches; light gray (2.5Y 7/2) sandy clay loam, light olive brown (2.5Y 5/3) moist; few fine faint yellowish brown (10YR 5/6) moist redox concentrations; weak fine and medium subangular blocky structure parting to weak very fine and fine granular; soft, very friable, slightly sticky and slightly plastic; few very fine roots; common very fine and few fine dendritic tubular pores; 10 percent mica flakes; 5 percent gravel; neutral (pH 7.3); clear wavy boundary. (0 to 11 inches thick)

2C--36 to 60 inches; pinkish gray (7.5YR 6/2) very gravelly sand, brown (7.5YR 5/2) moist; the upper 10 inches is stratified with lenses of loamy sand, sandy loam and loam with common fine and medium distinct strong brown (7.5YR 5/6) moist redox concentrations; single grain; loose, nonsticky and nonplastic; 10 percent mica flakes; 45 percent gravel, 5 percent cobbles; neutral (pH 6.8).

TYPE LOCATION: Beaverhead County, Montana; approximately 900 feet north and 1800 feet west of the SE corner of sec. 10, T. 5 S., R. 15 W. Wisdom topographic quadrangle, UTM 12T 0310006e, 5050781n. NAD 83

RANGE IN CHARACTERISTICS:
Mean annual soil temperature - 35 to 40 degrees F.
Mollic epipedon thickness - 7 to 16 inches
Depth to a lithologic discontinuity - 15 to 40 inches
Depth to a seasonally high water table - 24 to 42 inches

A horizons
Value: 3 to 5 dry; 2 or 3 moist
Chroma: 1 to 3; dry or moist
Texture: loam, silt loam or silty clay loam
Clay content: 18 to 35 percent
Rock fragments: 0 to 10 percent gravel
Mica flakes: 0 to 15 percent
Reaction: pH 6.5 to 7.5

Bw horizon
Hue: 10YR or 2.5Y; dry or moist
Value: 5 or 6 dry; 4 or 5 moist
Chroma: 1 to 3; dry or moist
Texture: loam, clay loam or silt loam
Clay content: 18 to 35 percent
Rock fragments: 0 to 10 percent gravel
Mica flakes: 0 to 15 percent
Reaction: pH 6.6 to 7.6

BC horizon
Hue: 10YR or 2.5Y; dry or moist
Value: 5 to 7 dry; 4 or 5 moist
Chroma: 1 to 3; dry or moist
Texture: sandy clay loam, loam, clay loam or silt loam
Clay content: 15 to 35 percent
Rock fragments: 0 to 30 percent gravel
Mica flakes: 0 to 15 percent
Reaction: pH 6.3 to 7.3

2C horizon
Hue: 7.5YR, 10YR or 2.5Y; dry or moist
Value: 5 to 7 dry; 4 to 6 moist
Chroma: 2 or 3; dry or moist
Texture: loamy sand, loamy coarse sand, sand or coarse sand
Clay content: 0 to 10 percent
Rock Fragments: 35 to 75 percent--30 to 50 percent gravel, 5 to 25 percent cobbles
Reaction: pH 6.6 to 7.3

COMPETING SERIES: There are no competing series.

GEOGRAPHIC SETTING:
Landform - flood plains, drainageways, swales and outwash plains
Elevation - 5,900 to 6,900 feet
Slope - 0 to 4 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 40 degrees F.
Frost-free period - 30 to 70 days

GEOGRAPHICALLY ASSOCIATED SOILS:
These are the Copperbasin, Mooseflat, Shewag and Wisdom soils. The Copperbasin soils do not have a cambic horizon. Mooseflat soils are poorly drained. Shewag and Wisdom soils are well drained.

DRAINAGE AND PERMEABILITY: Somewhat poorly drained; moderately slow permeability above the 2C horizon and rapid in the 2C horizon.

USE AND VEGETATION: Foxgulch soils are used for irrigated grass hay and irrigated pasture. The vegetation is mainly Garrison creeping foxtail, meadow foxtail, timothy, tufted hairgrass, and other miscellaneous sedges, rushes and forbs.

DISTRIBUTION AND EXTENT: Foxgulch soils are not extensive in the intermountain valleys of southwestern Montana. MLRAs - 43B, 44B.

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:
Mollic epipedon - from 1 to 16 inches (A1, A2 horizons)
Cambic horizon - from 16 to 30 inches (Bw horizon)
Horizons with redox concentrations - from 30 to 60 inches (C, 2C horizons)
Lithologic discontinuity - at 36 inches (2C horizon)
Particle-size control section - from 11 to 41 inches (A2, Bw, C, part of 2C horizons)

Foxgulch soils have a cryic temperature regime, an ustic moisture regime, and an aquic moisture subclass.

National Cooperative Soil Survey
U.S.A.