LOCATION BATA MTEstablished Series
TAXONOMIC CLASS: Loamy-skeletal, mixed, superactive Andic Glossocryalfs
TYPICAL PEDON: Bata gravelly ashy silt loam, forested. (Colors are for dry soil unless otherwise noted.)
Oi--0 to 2 inches; undecomposed and slightly decomposed forest litter.
Bw--2 to 11 inches; brown (7.5YR 5/4) gravelly ashy silt loam, brown (7.5YR 4/4) moist; moderate fine and medium granular structure; soft, very friable, nonsticky and nonplastic; many fine through coarse roots; many fine pores; 15 percent gravel; moderately acid (pH 6.0); clear wavy boundary. (7 to 11 inches thick)
2E/Bt--11 to 22 inches; E part (70 percent) is pinkish gray (7.5YR 7/2) gravelly loam, pinkish gray (7.5YR 6/2) moist interfingering into B part; B part (30 percent) is pink (7.5YR 7/4) gravelly loam, brown (7.5YR 5/4) moist; texture mixed is gravelly loam; weak medium subangular blocky structure; slightly hard, very friable, nonsticky and nonplastic; many fine and medium roots; many fine pores; 30 percent gravel; moderately acid (pH 5.7); clear wavy boundary. (8 to 18 inches thick)
2Bt1--22 to 38 inches; pink (7.5YR 7/4) very gravelly clay loam, brown (7.5YR 5/4) moist; moderate medium and fine subangular blocky structure; very hard, firm, slightly sticky and moderately plastic; few fine roots; common fine pores; few distinct clay films on faces of peds and lining pores; 40 percent gravel; moderately acid (pH 6.0); gradual wavy boundary.
2Bt2--38 to 60 inches; light brown (7.5YR 6/4) very gravelly clay loam, brown (7.5YR 4/4) moist; moderate medium subangular blocky structure; very hard, firm, slightly sticky and moderately plastic; few fine roots; common fine pores; continuous prominent clay films on faces of peds and lining pores; 35 percent gravel and 10 percent cobbles; slightly acid (pH 6.2).
TYPE LOCATION: Missoula County, Montana; approximately 1,450 feet east and 1,050 feet north of the SW corner of sec. 25, T. 18 N., R. 16 W.
RANGE IN CHARACTERISTICS:
Soil temperature - 37 to 44 degrees F. (mean temperature in June, July, and August is less than 59 degrees F.)
Moisture control section - between 4 and 12 inches.
Some pedons have a thin discontinuous E horizon above the Bw horizon. Some pedons have a 2E and 2Bt/E horizons.
Bw horizon - Hue: 10YR or 7.5YR
Value: 5 or 6 dry; 4 or 5 moist
Chroma: 4 or 6
Texture: ashy silt loam or ashy loam
Clay content: 5 to 15 percent
Rock fragments: 15 to 35 percent--0 to 10 percent cobbles and stones; 15 to 30 percent gravel.
Acid oxalate extractable Al + 1/2 Fe: more than 1.0 percent
Moist bulk density: 1.0 g/cc or less
Reaction: pH 5.1 to 6.5
2E/Bt horizon - Hue: 10YR, 7.5YR, or 5YR
Value: E part 6, 7, or 8 dry, 5 or 6 moist; B part 5, 6 or 7 dry, 4 or 5 moist
Chroma: E part 2 or 3; B part 3 or 4
Texture: loam, silt loam, fine sandy loam, sandy loam
Clay content, mixed: 12 to 25 percent
Rock fragments: 25 to 60 percent--0 to 15 percent cobbles and stones; 20 to 50 percent gravel
Reaction: pH 5.6 to 7.3
2Bt horizon - Hue: 10YR, 7.5YR, or 5YR
Value: 5, 6, or 7 dry; 4 or 5 moist
Chroma: 3, 4 or 6
Texture, less than 2 mm: sandy clay loam, clay loam or silty clay loam
Clay content: 20 to 35 percent
Rock fragments: 35 to 60 percent--0 to 15 percent cobbles and stones; 20 to 50 percent gravel
Reaction: pH 5.6 to 7.3
COMPETING SERIES:
Jimlake (MT) - have a BC horizon.
GEOGRAPHIC SETTING:
Landform- moraines in glaciated valleys and on mountain slopes.
Elevation - 3,800 to 7,500 feet.
Slope - 2 to 60 percent.
Parent material - volcanic ash over glacial till or colluvium.
Climate - long, cold winters; cool, moist springs; short summers.
Mean annual precipitation - 25 to 45 inches, much of which falls as snow and spring rain.
Mean annual temperature - 35 to 42 degrees F.
Frost-free period - 30 to 70 days.
GEOGRAPHICALLY ASSOCIATED SOILS:
DRAINAGE AND PERMEABILITY: Well drained; moderately slow permeability.
USE AND VEGETATION: Bata soils are used for timber production, as wildlife habitat, and for watersheds. The native vegetation is subalpine fir, western larch, Douglas-fir, Engelmann spruce, and lodgepole pine with an understory of queencup beadlily, twinflower, blue huckleberry, rusty menziesia, common beargrass, and grouse whortleberry.
DISTRIBUTION AND EXTENT: Bata soils are of moderate extent in western Montana. MLRA 43A, 43B, 44A, 44B and 46.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Bozeman, Montana.
SERIES ESTABLISHED: Missoula County, Montana, 1985.
REMARKS: Soil Interpretations Record: MT0161. Diagnostic horizons and features recognized in this pedon are: an ochric epipedon from the surface to 11 inches (Oi and Bw horizons); a glossic horizon from 11 to 22 inches (2E/Bt horizon); an argillic horizon from 22 to 60 inches (2Bt1, 2Bt2 horizons); a particle-size control section from 22 to 42 inches (2Bt1, 2Bt2 horizons). Bata soils have a udic moisture regime and a cryic temperature regime.
ADDITIONAL DATA: Laboratory data--SMT74-63-009.