LOCATION BEAVERELL MT

Established Series
Rev. DES-JAL-EMM
06/2012

BEAVERELL SERIES

The Beaverell series consists of very deep, well drained soils that formed in alluvium or glacial outwash that is 10 to 20 inches deep over very gravelly loamy sand or very gravelly sand. These soils are on stream terraces, outwash terraces, kames, eskers and alluvial fans. Slopes are 0 to 35 percent. Mean annual precipitation is about 12 inches, and mean annual temperature is about 41 degrees F.

TAXONOMIC CLASS: Loamy-skeletal over sandy or sandy-skeletal, mixed, superactive, frigid Calcidic Argiustolls

TYPICAL PEDON: Beaverell gravelly loam, grassland (colors are for dry soil unless otherwise noted).

A--0 to 3 inches; brown (10YR 5/3) gravelly loam, dark brown (10YR 3/3) moist; weak very fine granular structure; slightly hard, very friable, slightly sticky and nonplastic; many fine and very fine roots; many fine and medium pores; 15 percent gravel; neutral (pH 6.6); clear smooth boundary. (2 to 6 inches thick)

Bt1--3 to 9 inches; brown (10YR 5/3) very gravelly clay loam, dark brown (10YR 3/3) moist; moderate medium prismatic structure parting to moderate medium and fine blocky; hard, friable, moderately sticky and slightly plastic; many fine and very fine roots; many fine and very fine pores; many faint clay films on faces of peds; 35 percent gravel; neutral (pH 6.6); clear smooth boundary.

Bt2--9 to 11 inches; brown (10YR 5/3) very gravelly sandy clay loam, dark brown (10YR 3/3) moist; moderate fine blocky structure; slightly hard, very friable, slightly sticky and slightly plastic; common fine and very fine roots; many medium and fine pores; many faint clay films on faces of peds; 50 percent gravel; lime coatings on underside of larger gravel; neutral (pH 6.8); clear wavy boundary. (Combined thickness of Bt horizons is 7 to 19 inches)

2Bk1--11 to 17 inches; brown (10YR 5/3) very gravelly loamy sand, brown (10YR 4/3) moist; single grain; loose, very friable, nonsticky and nonplastic; common very fine roots; 60 percent gravel; continuous distinct lime coatings on underside of smaller gravel and lime casts on underside of larger gravel; disseminated lime; strongly effervescent; slightly alkaline (pH 7.8); gradual wavy boundary. (4 to 25 inches thick)

2Bk2--17 to 60 inches; brown (10YR 5/3) very gravelly sand, brown (10YR 4/3) moist; single grain; loose, soft and very friable; 60 percent gravel; common faint lime coating on underside of gravel; disseminated lime; strongly effervescent; slightly alkaline (pH 7.8).

TYPE LOCATION: Blaine County, Montana; 30 feet north and 1,000 feet west of the SE corner of sec. 15, T. 33 N., R. 23 E.

RANGE IN CHARACTERISTICS:

Soil temperature - 40 to 47 degrees F.
Moisture control section - between 4 and 12 inches; dry in all parts between four tenths and five tenths of the cumulative days per year when the soil temperature at 20 inches is 41 degrees F or higher.
Mollic epipedon thickness - 7 to 14 inches and may include all or part of the argillic horizon.
Depth to 2Bk horizon - 10 to 20 inches.
Soil phases - moderately wet.
A 2C horizon is allowed.

A horizon
Value: 2 or 3 moist
Chroma: 2 or 3
Texture: loam, sandy loam, clay loam or sandy clay loam
Clay content: 10 to 35 percent
Rock fragments: 5 to 70 percent--0 to 40 percent cobbles and stones, 5 to 40 percent gravel
Reaction: pH 4.5 to 7.8

Bt1 horizon
Hue: 10YR or 7.5YR
Value: 3, 4, or 5 dry; 2, 3, or 4 moist
Chroma: 2, 3, or 4
Texture: clay loam, sandy clay loam, or loam
Clay content: 20 to 35 percent
Rock fragments: 35 to 60 percent--0 to 15 percent cobbles, 30 to 45 percent gravel
Reaction: pH 6.6 to 7.8

Bt2 horizon
Hue: 10YR, 7.5Y, or 2.5Y
Value: 3, 4, or 5 dry; 2, 3, or 4 moist
Chroma: 2, 3, 4, or 6
Texture: clay loam, sandy clay loam, or loam
Clay content: 20 to 35 percent
Rock fragments: 35 to 70 percent--0 to 35 percent cobbles, 35 to 45 percent gravel
Reaction: pH 6.6 to 7.8

2Bk1 horizon
Hue: 10YR or 2.5Y
Value: 4, 5, 6, 7, or 8 dry; 4, 5, or 6 moist
Chroma: 2, 3, or 4
Texture: loamy sand, sand, or sandy loam
Clay content: 0 to 18 percent
Rock fragments: 35 to 75 percent--5 to 40 percent cobbles and stones, 30 to 45 percent gravel
Calcium carbonate equivalent: 5 to 15 percent
Reaction: pH 7.4 to 8.4

2Bk2 horizon
Hue: 10YR, 5YR, or 2.5Y
Value: 4, 5, or 6 dry; 3, 4, 5, or 6 moist
Chroma: 2, 3, 4, or 6
Texture: loamy sand, sand, loamy coarse sand or coarse sand
Clay content: 0 to 10 percent
Rock fragments: 35 to 80 percent--5 to 30 percent cobbles and stones, 30 to 60 percent gravel
Calcium carbonate equivalent: 2 to 15 percent
Reaction: pH 6.6 to 8.4

COMPETING SERIES:

There are no competing series.

GEOGRAPHIC SETTING:

Landform - stream terraces; outwash terraces; kames; eskers; alluvial fans.
Elevation - 2,400 to 6,500 feet.
Slope - 0 to 35 percent.
Parent material - alluvium or glacial outwash that is 10 to 20 inches deep over very gravelly loamy sand or very gravelly sand.
Climate - long cold winters; moist springs; hot, dry summers.
Mean annual precipitation - 10 to 14 inches.
Mean annual air temperature - 37 to 45 degrees F.
Frost-free period - 70 to 130 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Attewan and Wabek soils. Attewan soils are fine-loamy over sandy or sandy-skeletal. Wabek soils are sandy-skeletal and do not have argillic horizons.

DRAINAGE AND PERMEABILITY: Well drained; moderate permeability above the sandy-skeletal horizon and rapid in the sandy-skeletal horizon. Moderately wet phase has a seasonal high water table at 4 to 6 feet.

USE AND VEGETATION: Beaverell soils are used for irrigated small grain, irrigated hay and pasture, and as rangeland. Potential native vegetation is mainly western wheatgrass, bluebunch wheatgrass, green needlegrass, needleandthread, forbs, and shrubs.

DISTRIBUTION AND EXTENT: Beaverell soils are of moderate extent in Montana.

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

SERIES ESTABLISHED: Stillwater County, Montana, 1975.

REMARKS: Soil interpretation record: MT0178, MT1030.

Diagnostic horizons and features recognized in this pedon are:

Mollic epipedon - from the soil surface to 11 inches (A, Bt1, Bt2 horizons)
Argillic horizon - from 8 to 11 inches (Bt1, Bt2 horizons)
Horizon of carbonate accumulation (2Bk1, 2Bk2 horizons)
Calcic horizon - from 11 to 17 inches (2Bk1) and likely from 11 to 60 inches (2Bk1 and 2Bk2)
Sandy-skeletal material - from 17 to 60 inches (2Bk1, 2Bk2 horizons)
Particle-size control section - from 3 to 40 inches (Bt1, Bt2, 2Bk1, 2Bk2 horizons).

Beaverell soils have a frigid temperature regime and an ustic moisture regime that borders on aridic.

The 6/2012 revision reflects a reclassification from Aridic Argiustolls to Calcidic Argiustolls because the 2Bk1 horizon meets the criteria for a calcic horizon. A check of NASIS data shows that component data as populated for Bk horizons also consistently meets criteria for a calcic horizon. Classifications of Beaverell components in all survey areas should be reviewed as part of a future update project. The 2Bk2 horizon at the type location should be investigated to determine if it is part of the calcic horizon.

National Cooperative Soil Survey
U.S.A.