LOCATION MISHAKAL MTEstablished Series
TAXONOMIC CLASS: Fine, mixed, superactive, frigid Typic Argiustolls
TYPICAL PEDON: Mishakal loam, in forest (colors are for dry soil unless otherwise noted).
A1--0 to 3 inches; brown (10YR 4/3) channery loam, very dark grayish brown (10YR 3/2) moist; weak fine granular structure; soft, very friable, moderately sticky and slightly plastic; many fine and few fine and medium roots; 5 percent flagstones and 10 percent channers; neutral (pH 6.6); clear smooth boundary.
A2--3 to 10 inches; brown (10YR 4/3) clay loam, very dark grayish brown (10YR 3/2) moist; moderate fine subangular blocky structure; slightly hard, friable, very sticky and very plastic; many fine and very fine, common very fine and few fine and medium roots; common very fine and few fine tubular pores; 5 percent channers; neutral (pH 7.0); clear smooth boundary. (Combined thickness of A horizons is 8 to 15 inches.)
Bt1--10 to 17 inches; light olive brown (2.5Y 5/4) channery clay, olive brown (2.5Y 4/3) moist; weak fine prismatic structure parting to strong fine subangular blocky; very hard, firm, very sticky and very plastic; common very fine and few fine and medium roots; common very fine and few fine tubular pores; common distinct clay films on faces of peds; 15 percent channers; neutral (pH 7.2); gradual smooth boundary.
Bt2--17 to 28 inches; light olive brown (2.5Y 5/4) clay loam, olive brown (2.5Y 4/3) moist; weak medium subangular blocky structure; hard, firm, moderately sticky and very plastic; few very fine roots; few very fine tubular pores; few distinct clay films on faces of peds; 10 percent channers; slightly alkaline (pH 7.4); abrupt smooth boundary. (Combined thickness of Bt horizons is 12 to 30 inches.)
Cr--28 to 60 inches; fractured argillite.
TYPE LOCATION: Deer Lodge County, Montana; about 350 feet east and 700 feet north of SW corner of sec. 28, T. 5 N., R. 11 W.
RANGE IN CHARACTERISTICS:
Soil temperature - 39 to 45 degrees F.
Moisture control section - between 4 and 12 inches.
Mollic epipedon thickness - 8 to 15 inches.
Depth to Cr horizon - 20 to 40 inches.
Phases - moderately impacted.
A1 horizon - Hue: 10YR or 2.5Y
Value: 4 or 5 dry; 2 or 3 moist
Chroma: 2 or 3
Clay content: 18 to 27 percent
Rock fragments: 0 to 35 percent--0 to 10 percent flagstones; 0 to 25 percent channers
Reaction: pH 6.1 to 7.3
A2 horizon - Hue: 10YR or 2.5Y
Value: 4 or 5 dry; 2 or 3 moist
Chroma: 2 or 3
Clay content: 27 to 40 percent
Rock fragments: 0 to 35 percent--0 to 10 percent flagstones; 0 to 25 percent channers
Reaction: pH 6.1 to 7.3
Bt horizons - Hue: 10YR or 2.5Y
Value: 5 or 6 dry; 3 or 4 moist
Chroma: 3 or 4
Texture: clay loam or clay
Clay content: 35 to 50 percent
Rock fragments: 0 to 20 percent channers
Reaction: pH 6.6 to 7.8
COMPETING SERIES:
Alder - horizon of secondary carbonate accumulation.
Bacbuster - horizon of secondary carbonate accumulation.
Bigbear - very deep; has horizon of secondary carbonate accumulation.
Billman - rock fragments are mainly pebbles and cobbles; formed in residuum from interbedded sandstone and shale.
Charo - moderately deep to a lithic contact.
Darret - hues of 7.5YR or redder throughout.
Durston - very deep; has horizon of secondary carbonate accumulation.
Microy - moderately deep to a lithic contact.
Pino - moderately deep to a lithic contact.
Wilcoxson - deep to a lithic contact; has horizon of secondary carbonate accumulation.
GEOGRAPHIC SETTING:
Landform - mountains and hills.
Elevation - 5,200 to 6,600 feet.
Slope - 35 to 60 percent.
Parent material - residum from argilite.
Climate - long, cold winters; moist springs; warm summers.
Mean annual precipitation - 15 to 22 inches.
Mean annual air temperature - 37 to 43 degrees F.
Frost-free period - 70 to 90 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Roy, Tolbert, and Wilspring soils. Roy soils are very deep and clayey-skeletal. Tolbert soils are shallow to a lithic contact and are loamy-skeletal. Wilspring soils are moderately deep to a lithic contact and are loamy-skeletal. These soils are on similar landform positions.
DRAINAGE AND PERMEABILITY: Well drained; slow permeability.
USE AND VEGETATION: Mishakal soils are used for timber production, understory grazing, watershed and wildlife habitat. Potential native vegetation is mainly Douglas fir, limber pine and rocky mountain juniper with an understory of bluebunch wheatgrass, common juniper and woods rose.
DISTRIBUTION AND EXTENT: Mishakal soils are of small extent in southwestern Montana.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Bozeman, Montana
SERIES ESTABLISHED: Deer Lodge County, Montana, 2003.
REMARKS: Diagnostic horizons and features recognized in this pedon are: a mollic epipedon from the soil surface to 10 inches (A1 and A2 horizons); an argillic horizon which is the particle-size control section from 10 to 28 inches (Bt1 and Bt2 horizons); a paralithic contact at 28 inches (Cr horizon). Mishakal soils have a frigid temperature regime and an ustic moisture regime. Areas where the Mishakal series has been mapped in Deer Lodge County are moderately impacted from past smelter emissions and may contain significant levels of heavy metal contaminants in surface horizons.