LOCATION WHITEBEAR MTTentative Series
TAXONOMIC CLASS: Coarse-silty, mixed, superactive, frigid Typic Natrustalfs
TYPICAL PEDON: Whitebear silt loam, rangeland (Colors are for dry soil unless otherwise noted.)
E1--0 to 4 inches; light gray (10YR 7/1) silt loam, gray (10YR 5/1) moist; weak fine subangular blocky structure parting to moderate fine granular; slightly hard, friable, nonsticky and slightly plastic; few fine and medium roots; strongly effervescent; moderately alkaline (pH 8.4); gradual wavy boundary.
E2--4 to 10 inches; light gray (10YR 7/2) silt loam, light brownish gray (10YR 6/2) moist; weak medium subangular blocky structure parting to moderate fine platy; slightly hard, friable, nonsticky and slightly plastic; few fine roots; strongly effervescent; very strongly alkaline (pH 9.5); gradual wavy boundary. (Combined thickness of E horizons is 2 to 10 inches)
E/Btn--10 to 13 inches; E part (70 percent) light gray (10YR 7/2) silt loam, light brownish gray (10YR 6/2) moist; Bt part (30 percent) light brownish gray (2.5Y 6/2), dark grayish brown (2.5Y 4/2) moist; moderate medium prismatic structure parting to moderate fine platy; slightly hard, friable, slightly sticky and slightly plastic; few fine roots; few distinct clay films on faces of peds; strongly effervescent; very strongly alkaline (pH 10.0); clear wavy boundary. (0 to 4 inches thick)
Btn--13 to 18 inches; light brownish gray (2.5Y 6/2) loam, dark grayish brown (2.5Y 4/2) moist; moderate medium subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; few fine roots; common distinct clay films on faces of peds; strongly effervescent; very strongly alkaline (pH 10.1); clear wavy boundary. (5 to 20 inches thick)
BC--18 to 23 inches; light gray (2.5Y 7/2) silt loam, grayish brown (2.5Y 5/2) moist; massive; slightly hard, friable, slightly sticky and slightly plastic; few fine distinct light olive brown (2.5Y 5/4) redox concentrations; strongly effervescent; very strongly alkaline (pH 10.1); gradual wavy boundary. (0 to 16 inches thick)
C1--23 to 40 inches; pale yellow (2.5Y 8/2) silt, light brownish gray (2.5Y 6/2) moist; massive; slightly hard, friable, nonsticky and slightly plastic; common fine distinct light olive brown (2.5Y 5/4) redox concentrations; strongly effervescent; very strongly alkaline (pH 10.2); gradual wavy boundary. (10 to 20 inches thick)
C2--40 to 56 inches; pale yellow (2.5Y 8/2) silt loam, pale yellow (2.5Y 7/4) moist; thin platy varves; hard, firm, moderately sticky and moderately plastic; common fine distinct light olive brown (2.5Y 5/4) redox concentrations; strongly effervescent; very strongly alkaline (pH 9.5); gradual wavy boundry.
C3--56 to 60 inches; pale yellow (2.5Y 8/2) very fine sandy loam, pale yellow (2.5Y 7/4) moist; massive; slightly hard, friable, nonsticky and nonplastic; many fine distinct light olive brown (2.5Y 5/4) redox concentrations; slightly effervescent; moderately alkaline (pH 8.2).
TYPE LOCATION: Flathead County, Montana; 1,100 feet west and 900 feet south of the northeast corner of sec. 18, T. 27 N., R. 25 W. Mcgregor Peak topographic quadrangle. UTM zone 11: Northing 5330150, Easting 659120.
RANGE IN CHARACTERISTICS:
Average annual soil temperature - 42 to 45 degrees F.
Depth to seasonal high water table - 24 to 42 inches.
E horizons
Hue - 2.5Y or 10YR
Value - 5 to 7 dry, 3 to 6 moist
Chroma - 1 or 2
Texture - silt loam or silt
Clay content - 5 to 15 percent
EC - 1 to 2 mmhos/cm
SAR - 6 to 30
Reaction - pH 7.9 to 9.6
E/Btn horizon (some pedons have Btn/E)
Hue - 2.5Y or 10YR
Value - E part: 5 to 7 dry, 3 to 6 moist
Btn part: 4 to 7 dry, 3 to 5 moist
Chroma - 1 to 3
Texture - silt loam
Clay content - 8 to 18 percent mixed
EC - 1 to 4 mmhos/cm
SAR - 13 to 40
Reaction - pH 8.4 to 10.0
Btn horizon
Hue - 2.5Y or 10YR
Value - 4 to 7 dry, 3 to 5 moist
Chroma - 1 to 3
Texture - loam or silt loam
Clay content - 8 to 18 percent
EC - 2 to 4 mmhos/cm
SAR - 13 to 40
Reaction - pH 8.4 to 10.0
BC horizon
Hue - 2.5Y or 10YR
Value - 5 to 8 dry, 4 to 6 moist
Chroma - 1 or 2
Texture - silt loam or very fine sandy loam
Clay content - 5 to 15 percent
EC - 2 to 4 mmhos/cm
SAR - 13 to 40
Reaction - pH 8.4 to 10.0
C horizons
Hue - 2.5Y or 10YR
Value - 5 to 8 dry, 4 to 7 moist
Chroma - 1 to 3
Texture - silt, silt loam or very fine sandy loam
Clay content - 5 to 15 percent
Rock fragments - 0 to 35 percent, 0 to 30 percent gravel, 0 to 5 percent cobbles
EC - 1 to 4 mmhos/cm
SAR - 13 to 40
Reaction - pH 8.4 to 10.0
COMPETING SERIES: There are no competing series.
GEOGRAPHIC SETTING: Whitebear soils are lake terraces, flood plains and alluvial fans in mountain valleys. Slopes range from 0 to 2 percent. These soils formed in mixed lacustrine sediments. Elevations range from 3,100 to 3,600 feet. The average annual air temperature ranges from 43 to 47 degrees F., average annual precipitation ranges from 15 to 21 inches, and the average frost-free period is from 70 to 100 days
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Dahlake (T), Meadowpeak, McLangor, and Barzee series. Dahlake soils are on lake terraces and are fine-silty. Meadowpeak, McLangor, and Barzee soils are on floodplains and closed depressions. Meadowpeak soils do not have argillic horizons. McLangor soils have a histic epipedon. Barzee soils consist of organic materials.
DRAINAGE AND PERMEABILITY: Somewhat poorly drained, moderately slow permeability.
USE AND VEGETATION: These soils are used for rangeland, wildlife habitat, and watershed. Potential natural vegetation is mainly Alkali cordgrass, Alkali sacaton, Nuttall's alkaligrass, Inland saltgrass, Alkali bluegrass, and Fowl bluegrass.
DISTRIBUTION AND EXTENT: Northwestern Montana. This soil is not extensive. MLRA 44A.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Bozeman, Montana
SERIES PROPOSED: Flathead County, Montana, 2003. Whitebear is a coined name.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
Ochric epipedon - the zone from 0 to 13 inches (E, E/Btn horizons)
Natric horizon - the zone from 13 to 18 inches (Btn horizon)
Particle-size control section - the zone from 13 to 18 inches (Btn horizon)
Whitebear soils have an ustic moisture regime and a frigid temperature regime.
ADDITIONAL DATA: NSSL S92MT-029-001.