LOCATION FAIRSMITH               MT

Tentative Series
Rev. LCB-JAL-EMM
07/2012

FAIRSMITH SERIES

The Fairsmith series consists of very deep, somewhat poorly drained soils that formed in alluvium. These soils are on flood plains and flood plain steps. Slopes are 0 to 2 percent. Mean annual precipitation is about 13 inches and mean annual temperature is about 41 degrees F.

TAXONOMIC CLASS: Fine-loamy, mixed, superactive, calcareous, frigid Oxyaquic Ustifluvents

TYPICAL PEDON: Fairsmith silt loam, in irrigated hayland (colors are for dry soil unless otherwise noted).

Ap--0 to 7 inches; grayish brown (10YR 5/2) silt loam, dark grayish brown (10YR 4/2) moist; moderate medium and fine subangular blocky structure; soft, friable, moderately sticky and slightly plastic; many very fine roots; strongly effervescent; moderately alkaline (pH 8.2); clear smooth boundary. (5 to 9 inches thick)

Bw1--7 to 24 inches; light gray (2.5Y 7/2) loam with thin strata of silt loam, dark grayish brown (2.5Y 4/2) moist; weak medium prismatic structure parting to weak medium and coarse subangular blocky; soft, very friable, moderately sticky and slightly plastic; common very fine roots; many very fine tubular and interstitial pores; disseminated lime; violently effervescent; moderately alkaline (pH 8.2); clear smooth boundary.

Bw2--24 to 35 inches; light gray (2.5Y 7/2) silt loam with thin strata of loam, dark grayish brown (2.5Y 4/2) moist; weak medium and coarse subangular blocky structure; soft, very friable, moderately sticky and slightly plastic; common very fine roots; many very fine tubular and interstitial pores; common fine prominent brown (7.5YR 4/4) redox concentrations, moist; disseminated lime; violently effervescent; moderately alkaline (pH 8.2); gradual smooth boundary. (combined thickness of the Bw horizons is 23 to 35 inches thick)

Cg--35 to 50 inches; light gray (2.5Y 7/2) loam, with thin strata of silt loam and sandy loam, dark grayish brown (2.5Y 4/2) moist; massive; soft, very friable, sticky and slightly plastic; common very fine roots, few small pieces of charcoal; common fine prominent brown (7.5YR 4/4) redox concentrations, and common fine prominent dark gray (10YR 4/1) redox depletions, moist; disseminated lime; violently effervescent; moderately alkaline (pH 8.2); gradual smooth boundary. (12 to 20 inches thick)

2C--50 to 60 inches; light brownish gray (2.5Y 6/2) very gravelly sand, dark grayish brown (2.5Y 4/2) moist; single grain; loose, nonsticky and nonplastic; few fine and medium prominent brown (7.5YR 4/4) redox concentrations, moist; 50 percent gravel; disseminated lime; strongly effervescent; moderately alkaline (pH 8.2).

TYPE LOCATION: Meagher County, Montana; 1,200 feet south and 2,300 feet west of the NE corner of sec. 24, T. 12 N., R. 4 E.

RANGE IN CHARACTERISTICS:

Soil temperature - 40 to 45 degrees F.
Moisture control section - between 4 and 12 inches.
Depth to seasonal water table - 24 to 42 inches.
Depth to 2C horizon - 40 to 60 inches.

A horizon
Value: 5 or 6 dry; 3 or 4 moist
Chroma: 2 or 3
Clay content: 20 to 27 percent
Reaction: pH 7.9 to 8.4

Bw1 horizon
Hue: 10YR or 2.5Y
Value: 6 or 7 dry; 4 or 5 moist
Chroma: 2 or 3
Texture: silt loam or silty clay loam with thin strata of loam
Clay content: 20 to 30 percent
Reaction: pH 7.9 to 8.4

Bw2 horizon
Hue: 10YR or 2.5Y
Value: 6 or 7 dry; 4 or 5 moist
Chroma: 2 or 3
Redoximorphic features - Value: 5 or 6 dry, 4 or 5 moist; Chromas: 4 or 6
Texture: silt loam or silty clay loam with thin strata of loam
Clay content: 20 to 30 percent
Reaction: pH 7.9 to 8.4

Cg horizon
Value: 6 or 7 dry; 4 or 5 moist
Chroma: 1 or 2
Redoximorphic features - Hue: 7.5YR or 10YR; Value: 5 or 6 dry, 4 or 5 moist; Chroma: 2, 3, or 4
Texture: loam or silt loam with strata of sandy loam
Clay content: 15 to 25 percent
Reaction: pH 7.9 to 8.4

2C horizon
Hue: 2.5Y, 10YR, or 7.5YR
Chroma: 1 or 2
Redoximorphic features - Value: 5 or 6 dry, 4 or 5 moist; Chroma: 4 or 6
Texture: sand or loamy sand
Clay content: 0 to 5 percent
Rock fragments: 0 to 55 percent - 0 to 55 percent gravel, 0 to 5 percent cobbles.
Reaction: pH 7.9 to 8.4

COMPETING SERIES:

Pieriver (MT) - does not have a discontinuity of sandy of sandy-skeletal material at depths of 40 to 60 inches.

Thibadeau (MT) - has SAR of 13 to 20 in the particle-size control section.

GEOGRAPHIC SETTING:

Landform - flood plains.
Elevation - 4,500 to 6,000 feet.
Slope - 0 to 2 percent.
Parent material - alluvium.
Climate - long, cold winters; moist springs; short, warm summers.
Mean annual precipitation - 12 to 15 inches.
Mean annual air temperature - 38 to 43 degrees F.
Frost-free period - 80 to 100 days.

GEOGRAPHICALLY ASSOCIATED SOILS: This is the Nesda series. Nesda soils have a mollic epipedon and are sandy-skeletal.

DRAINAGE AND PERMEABILITY: Somewhat poorly drained; moderate permeability.

USE AND VEGETATION: Fairsmith soils are used mainly for grass and legume hay and grazing for livestock. The potential native vegetation is mainly basin wildrye, western wheatgrass, slender wheatgrass, bearded wheatgrass, canby bluegrass, sedges, shrubby cinquefoil, other perennial grasses, and forbs.

DISTRIBUTION AND EXTENT: Fairsmith soils are of small extent in the valleys of western Montana. MLRA 44B.

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

SERIES PROPOSED: Meagher County, Montana, 1992.

REMARKS: Soil interpretation record: MT1466.
Diagnostic horizons and features recognized in this pedon are:
Ochric epipedon - from the surface to 7 inches (A horizon);
Particle-size control section - from 10 to 40 inches (parts of the Bw and Cg horizons).

Fairsmith soils have a frigid temperature regime and an ustic moisture regime that borders on aquic.

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National Cooperative Soil Survey
U.S.A.