LOCATION FAIRWAY MT
Established Series
Rev. JB-KTS-JCK
04/2021
FAIRWAY SERIES
The Fairway series consists of very deep, somewhat poorly drained soils that formed in alluvium. These soils are on flood plains, flood-plain steps, stream terraces, and drainageways. Slopes are 0 to 4 percent. Mean annual precipitation is about 305 mm, and mean annual air temperature is about 6 degrees C.
TAXONOMIC CLASS: Fine-loamy, mixed, superactive, frigid Fluvaquentic Haplustolls
TYPICAL PEDON: Fairway silt loam, cultivated (colors are for dry soil unless otherwise noted).
Ap--0 to 20 cm; grayish brown (10YR 5/2) silt loam, very dark grayish brown (10YR 3/2) moist; moderate very fine and fine granular structure; slightly hard, friable, moderately sticky and slightly plastic; common very fine, medium and coarse roots; finely disseminated calcium carbonate; strongly effervescent; slightly alkaline (pH 7.6); clear smooth boundary.
A--20 to 38 cm; grayish brown (2.5Y 5/2) loam, very dark grayish brown (2.5Y 3/2) moist; weak medium prismatic structure parting to weak medium subangular blocky; slightly hard, friable, moderately sticky and slightly plastic; common very fine, medium and coarse roots; common very fine tubular and interstitial pores; finely disseminated calcium carbonate; strongly effervescent; slightly alkaline (pH 7.8); clear smooth boundary. (combined thickness of the A horizons is 25 to 46 cm thick)
Bk--38 to 76 cm; light brownish gray (2.5Y 6/2) silt loam, dark grayish brown (2.5Y 4/2) moist; weak medium prismatic structure parting to weak coarse subangular blocky; hard, friable, moderately sticky and slightly plastic; common very fine, medium and coarse roots; common very fine tubular and interstitial pores; few thin grayish brown (2.5Y 5/2) layers of soil, very dark grayish brown (2.5Y 3/2) moist; few fine threadlike and irregular calcium carbonate masses; strongly effervescent; slightly alkaline (pH 7.8); clear smooth boundary. (25 to 51 cm thick)
Bg--76 to 114 cm; light brownish gray (2.5Y 6/2) silty clay loam, dark grayish brown (2.5Y 4/2) moist; many fine and medium prominent reddish brown (5YR 4/4) moist redox concentrations; massive; hard, friable, moderately sticky and moderately plastic; finely disseminated calcium carbonate; slightly effervescent; neutral (pH 7.2); gradual smooth boundary. (25 to 61 cm thick)
2Cg--114 to 152 cm; light brownish gray (2.5Y 6/2) sand, dark grayish brown (2.5Y 4/2) moist; few fine and medium prominent brown (7.5YR 4/4) moist redox concentrations, moist; single grain; loose, nonsticky and nonplastic; neutral (pH 7.2). (0 to 51 cm thick)
TYPE LOCATION: Lewis and Clark County, Montana; 640 meters feet north and 732 meters east of the SW corner of sec. 15, T. 10 N., R. 3 W.
RANGE IN CHARACTERISTICS:
Mean annual soil temperature - 5.5 to 8.0 degrees C
Mollic epipedon thickness - 25 to 38 cm
Depth to lithologic discontinuity - 102 cm or more
Depth to seasonal high water table - 60 to 100 cm
Note: Some pedons do not have a thin layer of dark colored material in the Bk horizon. Some pedons have a Bkg horizon.
Ap horizon
Hue: 10YR or 2.5Y; dry or moist
Value: 4 or 5 dry; 2 or 3 moist
Chroma: 1 or 2; dry or moist
Texture: loam, silt loam, silty clay loam, clay loam or silty clay
Clay content: 15 to 45 percent
Electrical conductivity: 0 to 8 mmhos/cm
Calcium carbonate equivalent: 2 to 15 percent
Reaction: pH 6.6 to 8.4
A horizon
Hue: 10YR or 2.5Y; dry or moist
Value: 4 or 5 dry; 2 or 3 moist
Chroma: 1 to 3; dry or moist
Texture: loam, silt loam, clay loam or silty clay loam
Clay content: 18 to 35 percent
Rock fragments: 0 to 15 percent gravel
Electrical conductivity: 0 to 8 mmhos/cm
Calcium carbonate equivalent: 2 to 15 percent
Reaction: pH 6.6 to 8.4
Bk horizon
Hue: 10YR or 2.5Y; dry or moist
Value: 5 or 6 dry; 3 or 4 moist
Chroma: 2 or 3; dry or moist
Texture: loam, silt loam or clay loam
Clay content: 18 to 35 percent
Rock fragments: 0 to 15 percent gravel
Calcium carbonate equivalent: 5 to 15 percent
Reaction: pH 6.6 to 8.4
Bg horizon
Hue: 10YR or 2.5Y; dry or moist
Value: 5 or 6 dry; 3 or 4 moist
Chroma: 1 to 3; dry or moist
Texture: loam, silt loam, silty clay loam, with some thin strata of sandy loam, loamy sand and clay loam
Clay content: 18 to 30 percent
Rock fragments: 0 to 15 percent gravel
Calcium carbonate equivalent: 2 to 15 percent
Reaction: pH 6.6 to 8.4
2Cg horizon
Hue: 10YR, 2.5Y or 5Y; dry or moist
Value: 6 or 7 dry; 3 or 4 moist
Chroma: 1 or 2; dry or moist
Texture: sand, loamy sand, sandy loam or silt loam with strata of fine sand
Clay content: 0 to 22 percent
Rock fragments: 0 to 60 percent--0 to 55 percent gravel, 0 to 15 percent cobbles
Calcium carbonate equivalent: 0 to 15 percent
Reaction: pH 6.6 to 8.4
COMPETING SERIES:
Bobkitty (MT) - does not have a horizon of secondary calcium carbonate accumulation
Lander (WY) - does not have a horizon of secondary calcium carbonate accumulation
GEOGRAPHIC SETTING:
Landform - flood plains, flood-plain steps, stream terraces, and drainageways
Elevation - 1,128 to 1,890 meters
Slope - 0 to 4 percent
Parent material - alluvium
Climate - long, cold winters; moist springs; and warm summers
Mean annual precipitation - 254 to 559 mm, most of which falls during the spring and early summer
Mean annual air temperature - 3.9 to 7.2 degrees C
Frost-free period - 70 to 130 days
GEOGRAPHICALLY ASSOCIATED SOILS: None listed.
DRAINAGE AND PERMEABILITY: Somewhat poorly drained; moderate permeability above the 2Cg horizon and very rapid permeability below.
USE AND VEGETATION: Fairway soils are used mainly for irrigated crops, and some small areas are used for rangeland. Potential native vegetation is mainly reedgrass, western wheatgrass, slender wheatgrass, tufted hairgrass, basin wildrye, prairie cordgrass, sedges and forbs.
DISTRIBUTION AND EXTENT: Fairway soils are of moderate extent in western and central Montana. MLRAs - 43B, 44B, 46, 52, 58A.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Bozeman, Montana.
SERIES ESTABLISHED: Choteau-Conrad Area, parts of Teton and Pondera Counties, Montana, 1991; proposed in Lewis and Clark County, Montana, 1979.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
Mollic epipedon - from 0 to 38 cm (Ap and A horizons)
Secondary calcium carbonate accumulation - from 38 to 76 cm (Bk horizon)
Redox concentrations - from 76 to 152 cm (Bg and 2Cg horizons)
Lithologic discontinuity - at 114 cm (2Cg horizon)
Particle-size control section - from 25 to 100 cm (part of the A, Bk, and Bg horizons)
Fairway soils have a frigid temperature regime, an ustic moisture regime, and an aquic moisture subclass.
Redox depletions were not recorded at the type location in 1979. The need for documentation in support of the Fluvaquentic subgroup is recognized and should be investigated.
ADDITIONAL DATA: Soil Interpretation Records - MT0375, MT7046, MT7047.
National Cooperative Soil Survey
U.S.A.