LOCATION MUSSEL             MT+CO
Established Series
Rev. LCB-JAL
11/2002

MUSSEL SERIES


The Mussel series consists of very deep, well-drained soils that formed in alluvium or colluvium. The soils are on alluvial fans, hills, and stream terraces. Slopes are 0 to 25 percent. Mean annual precipitation is about 12 inches, and mean annual temperature is about 42 degrees F.

TAXONOMIC CLASS: Fine-loamy, mixed, superactive, calcareous, frigid Aridic Ustorthents

TYPICAL PEDON: Mussel loam in cropland (colors are for dry soil unless otherwise noted).

Ap--0 to 7 inches; light brownish gray (10YR 6/2) loam, very dark grayish brown (10YR 3/2) moist; weak medium blocky structure; hard, friable, slightly sticky and slightly plastic; slightly effervescent; moderately alkaline (pH 8.0); clear smooth boundary. (4 to 8 inches thick)

Bk1--7 to 41 inches; light gray (10YR 7/2) loam, brown (10YR 5/3) moist; weak coarse prismatic structure parting to weak very coarse platy; slightly hard, very friable, slightly sticky and slightly plastic; common fine roots, common fine tubular pores; common fine filaments and soft masses of lime; violently effervescent; moderately alkaline (pH 8.2); clear smooth boundary. (30 to 40 inches thick)

Bk2--41 to 47 inches; light brownish gray (10YR 6/2) gravelly loamy sand, dark grayish brown (10YR 4/2) moist; single grain; loose; 30 percent pebbles; lime is disseminated, strongly effervescent; moderately alkaline (pH 8.2); clear smooth boundary. (5 to 15 inches thick)

Bk3--47 to 60 inches; very pale brown (10YR 7/3) silt loam, pale brown (10YR 6/3) moist; massive; slightly hard, very friable, slightly sticky and slightly plastic; lime is disseminated, strongly effervescent; moderately alkaline (pH 8.2).

TYPE LOCATION: Broadwater County, Montana; 1,300 feet west and 450 feet north of the SE corner of sec. 3, T. 4 N., R. 1 E.

RANGE IN CHARACTERISTICS:

Soil temperature - 40 to 47 degrees F.
Moisture control section - between 4 and 12 inches.
Control section - 18 to 30 percent clay and 0 to 5 percent coarse fragments.
Depth to stratified material - mainly greater than 40 inches but ranges from 34 to 45 inches.
Soil phases - warm.

Ap horizon - Hue: 10YR, 5Y, or 2.5Y
Value: 5, 6, or 7 dry; 4 or 5 moist
Chroma: 2 or 3
Texture: loam, silt loam, or sandy loam
Clay content: 10 to 27 percent
Rock fragments: 0 to 30 percent pebbles
Reaction: pH 7.9 to 8.4

Bk1 horizon - Hue: 10YR, 5Y, or 2.5Y
Value: 5, 6, or 7 dry; 4, 5, or 6 moist
Chroma: 2 or 3
Texture: loam or sandy clay loam
Clay content: 18 to 30 percent
Rock fragments: 0 to 5 percent pebbles
Calcium carbonate equivalent: 5 to 15 percent
EC: 0 to 2 mmhos/cm
Reaction: pH 7.9 to 8.4

Bk2 horizon - Hue: 10YR, 5Y, or 2.5Y
Value: 5, 6, or 7 dry; 4, 5, or 6 moist
Chroma: 2 or 3
Clay content: 5 to 10 percent
Rock fragments: 0 to 30 percent pebbles
Calcium carbonate equivalent: 5 to 15 percent
EC: 0 to 4 mmhos/cm
Reaction: pH 7.9 to 8.4

Bk3 horizon - Hue: 10YR, 5Y, or 2.5Y
Value: 5, 6, or 7 dry; 4, 5, or 6 moist
Chroma: 2 or 3
Clay content: 10 to 25 percent
Rock fragments: 0 to 30 percent pebbles
Calcium Carbonate Equivalent: 5 to 15 percent
EC: 0 to 4 mmhos/cm
Reaction: pH 7.8 to 8.4

COMPETING SERIES:

Benz - has 15 to 30 SAR in the control section.

Bigpack - does not have horizons of secondary carbonate accumulation.

Delridge - moderately deep to a paralithic contact.

Hillon - formed in glacial till; has a bulk density greater than 1.55 g/ccm.

Patent - does not have a horizon of secondary carbonate accumulation.

GEOGRAPHIC SETTING:

Landform - alluvial fans, hills, and stream terraces.
Elevation - 3,800 to 5,200 feet. Elevations in Colorado range to 7,600 feet.
Slope - 0 to 25 percent.
Parent material - alluvium and colluvium from the surrounding uplands.
Climate - long, cold winters; moist springs and falls; hot, dry summers.
Mean annual precipitation - 10 to 15 inches, most of which falls during spring and the very early part of summer.
Mean annual temperature - 38 to 45 degrees F.
Frost-free period - 90 to 130 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Amesha, Crago, Musselshell, and Scravo series. These soils all have calcic horizons. In addition Amesha soils are coarse-loamy. Crago soils are loamy-skeletal. Musselshell soils are carbonatic. Scravo soils are sandy-skeletal.

DRAINAGE AND PERMEABILITY: Well-drained; moderate permeability.

USE AND VEGETATION: Mussel soils are used for crops and rangeland. The crops are wheat, barley, sugar beets, alfalfa hay, and pasture. The potential native vegetation is bluebunch wheatgrass, needleandthread, western wheatgrass, forbs, and shrubs.

DISTRIBUTION AND EXTENT: Valleys of western and central Montana and in Colorado. The Mussel soils are of moderate extent.

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

SERIES ESTABLISHED: Broadwater County Area, Montana, 1971

REMARKS: Soil Interpretation Records: MT0136, MT1011. Diagnostic horizons and features recognized in this pedon are: an ochric epipedon from the soil surface to 7 inches (Ap horizon). A Bk horizon from 7 to 60 inches (Bkl, Bk2, Bk3 horizons). A particle-size control section from 10 to 40 inches (Bk horizon). Mussel soils have a frigid temperature regime and an ustic moisture regime bordering on aridic. Additional data: S85MT-007-006.


National Cooperative Soil Survey
U.S.A.