LOCATION FERBALL                 MT

Established Series
Rev. PEM-KTS-RJS
04/2011

FERBALL SERIES

The Ferball series consists of very deep, well drained soils that formed in alluvium or colluvium. These soils are on alluvial fans, strike valleys and hills. Slopes are 2 to 35 percent. Mean annual precipitation is about 12 inches, and mean annual air temperature is about 41 degrees F.

TAXONOMIC CLASS: Fine-loamy, mixed, superactive, frigid Aridic Haplustalfs

TYPICAL PEDON: Ferball clay loam, in rangeland (colors are for dry soil unless otherwise noted).

A--0 to 5 inches; yellowish red (5YR 4/6) clay loam, reddish brown (5YR 4/4) moist; strong fine blocky structure parting to moderate fine granular; slightly hard, friable, moderately sticky and slightly plastic; many very fine and few fine roots; many very fine and fine pores; slightly effervescent; finely disseminated calcium carbonate; moderately alkaline (pH 8.0); clear smooth boundary. (3 to 5 inches thick)

Btk--5 to 12 inches; red (2.5YR 5/6) clay loam, red (2.5YR 4/6) moist; strong medium prismatic structure; hard, firm, moderately sticky and slightly plastic; many very fine and few fine roots; many very fine tubular pores; many faint clay films on faces of peds; few fine masses of calcium carbonate; strongly effervescent; moderately alkaline (pH 8.0); gradual wavy boundary. (7 to 10 inches thick)

Bk1--12 to 45 inches; red (2.5YR 5/6) clay loam, red (2.5YR 4/6) moist; moderate fine subangular blocky structure; slightly hard, friable, moderately sticky and slightly plastic; common very fine and few fine roots; many very fine tubular pores; finely disseminated calcium carbonate and few fine masses of calcium carbonate; violently effervescent; moderately alkaline (pH 8.0); gradual wavy boundary. (10 to 48 inches thick)

Bk2--45 to 60 inches; red (2.5YR 5/6) silty clay loam, red (2.5YR 4/6) moist; weak fine subangular blocky structure; slightly hard, friable, moderately sticky and slightly plastic; few very fine roots; common very fine tubular pores; finely disseminated calcium carbonate and few fine masses of calcium carbonate; violently effervescent; moderately alkaline (pH 8.0).

TYPE LOCATION: Jefferson County, Montana; 200 feet south and 2,900 feet west of the NE corner of sec. 27, T. 2 N., R. 3 W.

RANGE IN CHARACTERISTICS:
Soil temperature - 40 to 46 degrees F.
Depth to top of argillic horizon - 3 to 5 inches
Depth to Bk horizon - 10 to 15 inches

Note: Some pedons may have a Bt horizon above the Btk horizon.

A horizon
Hue: 5YR or 7.5YR; dry or moist
Value: 4 or 5 dry; 3 or 4 moist
Chroma: 3 to 6; dry or moist
Texture: loam or clay loam
Clay content: 22 to 30 percent
Rock fragments: 0 to 15 percent gravel
Calcium carbonate equivalent: 0 to 5 percent
Reaction: pH 7.4 to 8.4

Btk horizon
Hue: 2.5YR or 5YR; dry or moist
Value: 5 or 6 dry; 4 or 5 moist
Chroma: 4 to 8; dry or moist
Texture: loam, clay loam or silty clay loam
Clay content: 25 to 35 percent
Rock fragments: 0 to 15 percent gravel
Calcium carbonate equivalent: 5 to 10 percent
Reaction: pH 7.9 to 8.4

Bk horizons
Hue: 2.5YR or 5YR; dry or moist
Value: 5 or 6 dry; 3 to 5 moist
Chroma: 4 to 8; dry or moist
Texture: loam, clay loam or silty clay loam
Clay content: 15 to 30 percent
Rock fragments: 0 to 35 percent gravel
Calcium carbonate equivalent: 5 to 15 percent
Reaction: pH 7.9 to 8.4

COMPETING SERIES:
Bondoe (MT) - have loamy-skeletal below the argillic horizon
Bonfri (MT) - is moderately deep to a paralithic contact
Chinatown (MT) - is moderately deep to a lithic contact
Fattig (MT) - is moderately deep to a lithic contact
Foreleft (MT) - does not have hues of 7.5YR or redder
Raghorn (MT) - does not have secondary calcium carbonate accumulation

GEOGRAPHIC SETTING:
Landform - alluvial fans, strike valleys and hills
Elevation - 3,800 to 6,300 feet
Slope - 2 to 35 percent
Parent material - alluvium or colluvium
Climate - long, cold winters; moist springs; warm summers
Mean annual precipitation - 10 to 16 inches
Mean annual air temperature - 40 to 44 degrees F.
Frost-free period - 80 to 115 days

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Redfist, Quaint and Quincreek series. Quincreek and Redfist soils are on similar landforms, but have a loamy-skeletal family. Quaint soils are on ridges and are less than 20 inches to lithic contact.

DRAINAGE AND PERMEABILITY: Well drained; moderately slow permeability.

USE AND VEGETATION: Ferball soils are mainly used for rangeland. The potential native vegetation is mainly bluebunch wheatgrass, western wheatgrass, green needlegrass, needleleaf sedge, eriogonum, milkvetch, fringed sagewort, big sagebrush.

DISTRIBUTION AND EXTENT: Ferball soils are of small extent in southwestern Montana. MLRAs - 43B, 44B.

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

SERIES ESTABLISHED: Jefferson County, Montana, 1998.

REMARKS: Diagnostic horizons and features recognized in this pedon are:
Ochric epipedon - from 0-5 inches (A horizon)
Argillic horizon - from 5 to 12 inches (Btk horizon)
Secondary calcium carbonate accumulation - from 5 to 60 inches (Btk, Bk1, Bk2 horizons)
Particle-size control section - from 5 to 12 inches (Btk horizon)

Ferball soils have a frigid temperature regime and an ustic moisture regime bordering on aridic.

Additional Information: Classification changed from Typic Eutroboralfs in 1997.

ADDITIONAL DATA: Soil interpretation record - MT1565.

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National Cooperative Soil Survey
U.S.A.