LOCATION MEADOWCREEK MT
Established Series
Rev. DES-WDB-JCK
04/2021
MEADOWCREEK SERIES
The Meadowcreek series consists of very deep, somewhat poorly drained soils that formed in alluvium. They are on flood plains, flood-plain steps, drainageways, and stream terraces. 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 over sandy or sandy-skeletal, mixed, superactive, frigid Fluvaquentic Haplustolls
TYPICAL PEDON: Meadowcreek loam, cultivated (colors are for dry soil unless otherwise noted).
Ap--0 to 13 cm; grayish brown (10YR 5/2) loam, very dark grayish brown (10YR 3/2) moist; weak fine and medium subangular blocky structure; slightly hard, friable, moderately sticky and slightly plastic; many very fine roots; strongly effervescent; moderately alkaline (pH 8.0); abrupt smooth boundary. (10 to 18 cm thick)
A1--13 to 25 cm; grayish brown (10YR 5/2) loam, very dark grayish brown (10YR 3/2) moist; weak medium prismatic structure parting to weak fine and medium subangular blocky; slightly hard, friable, moderately sticky and slightly plastic; common very fine roots; many fine tubular and interstitial pores; strongly effervescent; moderately alkaline (pH 8.0); clear smooth boundary. (8 to 20 cm thick)
A2--25 to 38 cm; gray (10YR 5/1) silt loam, very dark gray (10YR 3/1) moist; weak medium prismatic structure; slightly hard, friable, moderately sticky and slightly plastic; common very fine roots; many very fine tubular and interstitial pores; slightly alkaline (pH 7.4); clear smooth boundary. (0 to 15 cm thick)
Bg1--38 to 69 cm; light brownish gray (10YR 6/2) loam, dark grayish brown (10YR 4/2) moist; few fine distinct brown (7.5YR 5/3) moist redox concentrations; weak coarse prismatic structure; few thin very dark grayish brown (10YR 3/2) moist, layers of soil; slightly hard, friable, moderately sticky and slightly plastic; common very fine roots; many very fine tubular and interstitial pores; neutral (pH 7.0); gradual smooth boundary. (13 to 38 cm thick)
Bg2--69 to 79 cm; gray (10YR 6/1) sandy loam, dark grayish brown (10YR 4/2) moist; common fine distinct brown (7.5YR 5/4) moist redox concentrations; weak coarse prismatic structure; slightly hard, friable, nonsticky and moderately plastic; common very fine roots; many very fine tubular and interstitial pores; 5 percent gravel; neutral (pH 7.2); clear smooth boundary. (0 to 12 cm thick)
2C--79 to 152 cm; varigated colors, very gravelly sand; single grain; loose, nonsticky and nonplastic; few very fine roots; 55 percent gravel; neutral (pH 7.2).
TYPE LOCATION: Lewis and Clark County, Montana; 396 meters south and 610 meters east of the NW corner of sec. 8, T. 10 N., R. 3 W. Latitude is 46 degrees, 30 minutes, 35 seconds; longitude is 112 degrees, 00 minutes, 47 seconds.
RANGE IN CHARACTERISTICS:
Soil temperature - 5.5 to 8.0 degrees C
Mollic epipedon thickness - 25 to 38 cm
Depth to lithologic discontinuity - 50 to 100 cm
Depth to seasonal high water table - 60 to 100 cm
A horizons
Hue: 10YR or 2.5Y
Value: 4 or 5 dry; 2 or 3 moist
Chroma: 1 or 2
Texture: loam, silt loam, clay loam, or silty clay loam with thin strata of sandy loam or sandy clay loam
Clay content: 18 to 35 percent
Rock fragments: 0 to 15 percent--0 to 10 percent gravel; 0 to 5 percent cobbles
Electrical conductivity: 0 to 8 mmhos/cm
Calcium carbonate equivalent: 0 to 10 percent
Reaction: pH 6.6 to 8.4
Bg horizons
Hue: 10YR, 2.5Y or 5Y
Value: 5 or 6 dry; 3 or 4 moist
Chroma: 1, 2, or 3
Texture: loam, sandy loam, sandy clay loam, or silt loam, with some thin strata of fine sandy loam
Clay content: 18 to 25 percent
Rock fragments: 0 to 5 percent gravel
Electrical conductivity: 0 to 4 mmhos/cm
Calcium carbonate equivalent: 0 to 10 percent
Reaction: pH 6.1 to 8.4
2C horizon
Texture: sand, coarse sand or loamy sand
Clay content: 0 to 10 percent
Rock fragments: 35 to 75 percent--35 to 70 percent gravel; 0 to 15 percent cobbles and stones
Reaction: pH 6.1 to 8.4
COMPETING SERIES: There are no competing series.
GEOGRAPHIC SETTING:
Landform - flood plains, flood-plain steps, drainageways, and stream terraces
Elevation - 1,067 to 1,890 meters
Slope - 0 to 4 percent
Parent material - alluvium
Climate - long, cold winters; moist springs; warm, dry summers
Mean annual precipitation - 254 to 483 mm
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 over very rapid permeability.
USE AND VEGETATION: Meadowcreek soils are used mainly for irrigated crops. Some small areas are used for rangeland. Potential native vegetation is mainly western wheatgrass, slender wheatgrass, tall reedgrass, basin wildrye, prairie cordgrass, tufted hairgrass, sedges, and forbs.
DISTRIBUTION AND EXTENT: Meadowcreek soils are of moderate extent in western Montana. MLRAs - 43B, 44B, 46, 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, A1, and A2 horizons)
Redox concentrations - 38 to 79 cm (Bg1 and Bg2 horizons)
Lithologic discontinuity - at 79 cm (2C horizon)
Particle-size control section - from 25 to 100 cm (A2, Bg1, Bg2, and part of the 2C horizons)
Meadowcreek 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 record - MT0407
National Cooperative Soil Survey
U.S.A.