LOCATION MOOSEFLAT               MT

Established Series
Rev. TJK-KTS-RJS
05/2011

MOOSEFLAT SERIES


The Mooseflat series consists of very deep, very poorly drained soils that formed in alluvium. These soils are on flood plains, stream terraces, drainageways, depressions and mountain bases. Slopes are 0 to 8 percent. Mean annual precipitation is about 17 inches, and mean annual air temperature is about 38 degrees F.

TAXONOMIC CLASS: Fine-loamy over sandy or sandy-skeletal, mixed, superactive Typic Cryaquolls

TYPICAL PEDON: Mooseflat loam, in pasture (colors are for moist soil unless otherwise noted).

Oe--0 to 2 inches; black (10YR 2/1) moderately decomposed plant material, very dark grayish brown (10YR 3/2) dry; neutral (pH 6.8); clear smooth boundary. (0 to 4 inches thick)

A--2 to 10 inches; black (10YR 2/1) loam, gray (10YR 5/1) dry; many fine prominent yellowish brown (10YR 5/6) redox concentrations; moderate medium granular structure; slightly hard, friable, slightly sticky and moderately plastic; many very fine and fine roots; many very fine and fine pores; neutral (pH 7.2); clear smooth boundary. (6 to 15 inches thick)

Bg--10 to 18 inches; very dark gray (10YR 3/1) silt loam, gray (10YR 5/1) dry; common fine prominent dark yellowish brown (10YR 4/6) redox concentrations; weak thin platy structure; hard, friable, slightly sticky and slightly plastic; many very fine and fine roots; common very fine pores; neutral (pH 6.8); abrupt smooth boundary. (0 to 12 inches thick)

2BCg--18 to 22 inches; dark gray (10YR 4/1) loamy fine sand, light gray (10YR 7/1) dry; common fine distinct yellowish brown (10YR 5/4) redox concentrations; weak medium subangular blocky structure; soft, very friable, nonsticky and nonplastic; few fine roots; 5 percent gravel; neutral (pH 6.8); abrupt smooth boundary. (0 to 6 inches thick)

2Cg--22 to 60 inches; gray (10YR 5/1) extremely cobbly loamy sand, gray (10YR 6/1) dry; single grain; loose, nonsticky and nonplastic; 25 percent gravel and 35 percent cobbles; neutral (pH 7.2).

TYPE LOCATION: Jefferson County, Montana; 1,600 feet east and 1,700 feet south of the NW corner of sec. 22, T. 6N, R. 6W.

RANGE IN CHARACTERISTICS:
Soil temperature - 35 to 42 degrees F.
Mollic epipedon thickness - 10 to 19 inches
Depth to lithologic discontinuity - 14 to 26 inches
Depth to seasonal high water table - 0 to 12 inches during the months of April to June

Note: Some pedons may have a Bw and/or Cg horizon.

A horizon
Hue: 10YR, 2.5Y or 5Y; dry or moist
Value: 4 or 5 dry; 2 or 3 moist
Chroma: 1 or 2; dry or moist
Texture: loam, silty clay loam or silt loam
Clay content: 15 to 35 percent
Rock fragments: 0 to 10 percent--0 to 5 percent gravel, 0 to 5 percent cobbles
Reaction: pH 5.6 to 7.3

Bg horizon
Hue: 10YR, 2.5Y or 5Y; dry or moist
Value: 4 to 6 dry; 2 to 5 moist
Chroma: 1 or 2; dry or moist
Texture: sandy loam, loam, silt loam or silty clay loam
Clay content: 15 to 35 percent
Rock fragments: 0 to 20 percent--0 to 15 percent gravel, 0 to 5 percent cobbles
Reaction: pH 6.1 to 7.8

2BCg horizon
Hue: 10YR, 2.5Y or 5Y; dry or moist
Value: 6 or 7 dry; 4 or 5 moist
Chroma: 1 or 2; dry or moist
Texture: sandy loam, fine sandy loam or loamy fine sand
Clay content: 10 to 18 percent
Rock fragments: 5 to 20 percent--5 to 15 percent gravel, 0 to 5 percent cobbles
Reaction: pH 6.1 to 7.8

2Cg horizon
Hue: 10YR or 2.5Y; dry or moist
Value: 5 to 7 dry; 4 to 6 moist
Chroma: 1 to 3; dry or moist
Texture: sand, loamy sand, coarse sand or loamy coarse sand
Clay content: 0 to 12 percent
Rock fragments: 35 to 70 percent--20 to 35 percent gravel, 10 to 50 percent cobbles and stones
Reaction: pH 5.6 to 7.8

COMPETING SERIES:
Foxcreek (ID) - have secondary calcium carbonate accumulation
Walden (CO) - have a calcic horizon

GEOGRAPHIC SETTING:
Landform - flood plains, stream terraces, drainageways, depressions, and mountain bases
Elevation - 5,200 to 8,000 feet
Slope - 0 to 8 percent. (Slopes are as high as 50 percent in seeped areas of mountains.)
Parent material - alluvium
Climate - long, cold winters; cool moist springs; short, cool summers
Mean annual precipitation - 14 to 24 inches
Mean annual air temperature - 34 to 40 degrees F.
Frost-free period - 30 to 70 days

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Elvick and Libeg soils. Elvick soils are loamy-skeletal, do not have a mollic epipedon, and are somewhat poorly drained. Libeg soils are loamy-skeletal, have an argillic horizon, and are well drained. These soils are on higher landform positions.

DRAINAGE AND PERMEABILITY: Very poorly drained; moderate over rapid permeability.

USE AND VEGETATION: Mooseflat soils are primarily used for rangeland and wildlife habitat. The potential native vegetation is mainly northern reedgrass, bluejoint reedgrass, American mannagrass, tufted hairgrass, mountain alder, tall sedges and willows.

DISTRIBUTION AND EXTENT: Mooseflat soils are of small extent in southwestern Montana. MLRA - 43B, 44B.

MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Bozeman, Montana.

SERIES ESTABLISHED: Gallatin County, Montana, 1997; proposed Jefferson County, Montana, 1994.

REMARKS: Diagnostic horizons and features recognized in this pedon are:
Mollic epipedon - from 2 to 18 inches (A, Bg horizons)
Lithologic discontinuity - at 18 inches (2BCg horizon)
Strongly contrasting particle-size class - between the fine-loamy Bg horizon and the sandy 2BCg horizon
Particle-size control section - from 12 to 42 inches (part of Bg, BCg, part of 2Cg horizons)

Mooseflat soils have a cryic temperature regime and an aquic moisture regime.

ADDITIONAL DATA: Soil interpretive record - MT1521.


National Cooperative Soil Survey
U.S.A.