LOCATION TIMBERLIN MTEstablished Series
TAXONOMIC CLASS: Loamy-skeletal, mixed, superactive Ustollic Haplocryalfs
TYPICAL PEDON: Timberlin flaggy loam, forested (colors are for dry soil unless otherwise noted).
Oi--0 to 1 inch; slightly decomposed needles, twigs and leaves.
A--1 to 6 inches; grayish brown (10YR 5/2) flaggy loam, very dark gray (10YR 3/1) moist; moderate medium granular structure; soft, very friable, slighty sticky and slightly plastic; many very fine and fine, common medium and few coarse roots; 15 percent channers, 15 percent flagstones, 3 percent stones; neutral (pH 6.6); clear smooth boundary. (4 to 9 inches thick)
Bt1--6 to 11 inches; brown (10YR 5/3) very flaggy clay loam, brown (10YR 4/3) moist; moderate fine subangular blocky structure; slightly hard, very friable, moderately sticky and moderately plastic; common very fine and fine, few medium and coarse roots; common distinct clay films on faces of peds and lining pores; 15 percent channers and 30 percent flagstones; neutral (pH 6.6); clear smooth boundary.
Bt2--11 to 25 inches; brown (10YR 5/3) very flaggy clay loam; brown (10YR 4/3) moist; moderate medium subangular blocky structure; slighty hard, friable, very sticky and very plastic; common very fine and few fine and medium roots; common distinct clay films on faces of peds and lining pores; 15 percent channers, 30 percent flagstones; slightly acid (pH 6.4); clear wavy boundary. (Combined thicknes of Bt horizons is 16 to 31 inches).
Cr--25 to 30 inches; pale brown (10YR 6/3) semiconsolidated shale that textures to clay loam; slightly acid (pH 6.4).
R--30 inches; olive (5Y 5/3) hard sandstone.
TYPE LOCATION: Gallatin County, Montana; 1400 feet south and 300 feet east of the NW corner of sec. 11, T.1N.,R. 7E.
RANGE IN CHARACTERISTICS:
Mean annual soil temperature - 36 to 40 degrees F.
Mean summer soil temperature - 45 to 47 degrees F.
Moisture control section - between 4 and 12 inches.
Depth to R horizon - 20 to 40 inches.
Note: The A horizon does not meet the thickness requirements for a mollic epipedon.
A horizon - Value: 4 or 5 dry; 2 or 3 moist
Chroma: 1 or 2
Clay content: 18 to 27 percent
Rock fragments: 5 to 35 percent--5 to 25 percent channers or angular pebbles, 0 to 20 percent flagstones or angular cobbles, 0 to 3 percent stones.
Reaction: pH 6.6 to 7.3
Note: Some pedons contain an E horizon below the A horizon.
Bt1 horizon - Hue: 10YR or 2.5Y
Value: 5 or 6 dry; 4 or 5 moist
Chroma: 3 or 4
Texture: loam, sandy clay loam or clay loam
Clay content: 25 to 35 percent
Rock fragments: 35 to 60 percent--15 to 40 percent channers or angular pebbles, 5 to 35 percent flagstones or angular cobbles
Reaction: pH 6.1 to 7.3
Bt2 horizon - Hue: 10YR or 2.5Y
Value: 5 or 6 dry; 4 or 5 moist
Chroma: 3 or 4
Texture: loam, sandy clay loam or clay loam
Clay content: 25 to 35 percent
Rock fragments: 35 to 70 percent--15 to 45 percent channers or angular pebbles, 5 to 40 percent flagstones or angular cobbles
Reaction: pH 6.1 to 7.3
COMPETING SERIES:
Buffmeyer (CO) - does not have a lithic contact above 60 inches; does not have an O horizon; has 8 to 18 percent clay in the particle-size control section.
Guiser (NV) - does not have a lithic contact above 60 inches; has 18 to 25 percent clay in the particle-size control section; has mean annual soil temperature of 42 to 44 degrees F.
Namon (UT) - does not have a lithic contact at 20 to 40 inches; has transitional BE horizon; has mean annual soil temperature of 41 to 45 degrees F.
Rocko (MT) - does not have a lithic contact above 60 inches.
Scandard (CO) - has argillic horizon with hue of 10R to 5YR.
Wapshilla (ID) - does not have a lithic contact above 60 inches; has mean annual soil temperature of 43 to 47 degrees F.; formed in loess mixed with basalt colluvium.
GEOGRAPHIC SETTING:
Landform - mountains and hills.
Elevation - 5,200 to 7,500 feet.
Slope - 15 to 60 percent.
Parent material - interbedded sandstone and shale residuum or colluvium.
Climate - long, cold winters; cool, moist springs; short summers.
Mean annual precipitation - 17 to 24 inches.
Mean annual air temperature - 34 to 39 degrees F.
Frost-free period - 50 to 70 days.
DRAINAGE AND PERMEABILITY: Well drained; moderately slow permeability.
USE AND VEGETATION: Timberlin soils are used mainly for woodland and wildlife habitat. Potential native vegetation may include Douglas fir, lodgepole pine, common snowberry, white spiraea, elk sedge, western meadowrue and Engelmann aster.
DISTRIBUTION AND EXTENT: Timberlin soils are of small extent in southwestern Montana.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Bozeman, Montana
SERIES ESTABLISHED: Gallatin County, Montana, 1997.
REMARKS: Soil interpretation record: MT1623. Diagnostic horizons and features recognized in this pedon are: an ochric epipedon from the soil surface to 5 inches (A horizon); an argillic horizon from 5 to 24 inches (Bt1 and Bt2 horizons); a particle size control section from 5 to 24 inches (Bt1 and Bt2 horizons). Timberline soils have a cryic temperature regime and an ustic moisture regime.