LOCATION BEARSPRING WAEstablished Series
TAXONOMIC CLASS: Loamy-skeletal, isotic, frigid Vitrandic Haploxerolls
TYPICAL PEDON: Bearspring cobbly ashy loam - on a 65 percent north-facing slope, at 2,720 feet elevation, under a mixed ponderosa pine-Douglas-fir canopy. (Colors are for dry soil unless otherwise stated.)
Oi--0 to 1 inch; needles, leaves, bark and partially decomposed organic matter; abrupt smooth boundary.
A1--1 to 7 inches; grayish brown (10YR 5/2) cobbly ashy loam, very dark grayish brown (10YR 3/2) moist; moderate fine subangular blocky structure; soft, very friable, nonsticky and nonplastic, many very fine, fine, and few medium roots; 15 percent angular gravel and 15 percent angular cobbles; neutral (pH 6.8); clear wavy boundary.
A2--7 to 12 inches; brown (10YR 5/3) gravelly ashy loam, dark brown (10YR 3/3) moist; moderate medium subangular blocky structure; soft, very friable, nonsticky and nonplastic; many very fine, fine, and few medium roots; 25 percent angular gravel; slightly acid (pH 6.2); clear wavy boundary. (Combined thickness of the A horizon is 10 to 15 inches)
Bw1--12 to 20 inches; pale brown (10YR 6/3) gravelly loam, brown (10YR 4/3) moist; weak fine subangular blocky structure; soft, very friable, nonsticky and nonplastic; common very fine and fine roots; 30 percent angular gravel; slightly acid (pH 6.2); abrupt wavy boundary.
Bw2--20 to 28 inches; pale brown (10YR 6/3) very gravelly sandy loam, brown (10YR 4/3) moist; massive; soft, very friable, nonsticky and nonplastic; common fine roots; 35 percent angular gravel and 5 percent angular cobbles; slightly acid (pH 6.4); gradual wavy boundary. (Combined thickness of Bw horizon is 7 to 35 inches)
C1--28 to 51 inches; pale brown (10YR 6/3) very cobbly sandy loam, yellowish brown (10YR 5/4) moist; massive; soft, very friable, nonsticky and nonplastic; common fine roots; 10 percent angular gravel and 40 percent angular cobbles; slightly acid (pH 6.4); clear wavy boundary. (13 to 23 inches thick)
C2--51 to 60 inches; light yellowish brown (10YR 6/4) extremely gravelly coarse sandy loam, yellowish brown (10YR 5/4) moist; massive; soft, very friable, nonsticky and nonplastic; 75 percent angular gravel; neutral (pH 6.6).
TYPE LOCATION: Colville Indian Reservation; Okanogan County, Washington; about 7 miles southeast of the town of Nespelem; 2,300 feet south, 400 feet west of the northeast corner of section 12, T. 30 N., R. 31 E., W.M.
RANGE IN CHARACTERISTICS: The mean annual soil temperature is 40 to 46 degrees F. These soils are usually moist but are dry for 60 to 75 consecutive days following the summer solstice. The mollic epipedon is 10 to 15 inches. The base saturation (by sum of cations) is assumed to be above 75 percent throughout most of the particle-size control section, but to be less than 75 percent in part of the mollic epipedon. The upper 10 to 15 inches has an estimated moist bulk density of 1.10 to 1.50 g/cc, volcanic glass content of 5 to 20 percent, acid-oxalate extractable aluminum plus one-half of the acid-oxalate extractable iron of 0.4 to 1.0 percent, and 15-bar water retention of 5 to 12 percent for air dried samples. The particle-size control section averages 7 to 15 percent clay and 35 to 50 percent angular granitic rock fragments. Reaction is slightly acid or neutral throughout.
The A horizon has value of 4 or 5 dry, and chroma of 1 to 3 dry or moist. It is ashy loam, gravelly ashy loam, gravelly ashy sandy loam or cobbly ashy loam. This horizon is 5 to 25 percent angular gravel and 0 to 15 percent cobbles.
The Bw horizon has value of 5 to 7 dry, 4 or 5 moist, and chroma of 2 to 4 dry or moist. It is loam or sandy loam and is gravelly, very gravelly, or very cobbly. This horizon is 15 to 45 percent angular granitic gravel, 0 to 15 angular granitic cobbles, and 0 to 10 percent angular granitic stones.
The C horizon has value of 6 or 7 dry, 4 or 5 moist, and chroma of 2 to 4 dry or moist. It is sandy loam or coarse sandy loam and may be loamy coarse sand in the lower part of the horizon. It is very gravelly, very cobbly, extremely gravelly, or extremely cobbly. This horizon is 15 to 75 percent angular granitic gravel, 0 to 40 percent angular granitic cobbles, and 0 to 15 percent angular granitic stones.
COMPETING SERIES: These are the Cassal, Cherrycreek, Eastpine, Egyptcreek, Fredonyer, Longs, Midpeak, Mineral, Peahke, Scoap, Shalrock, Shilling, Umatilla, and Yellcreek series. Cassal soils have distinct redox features at 30 to 45 inches. Cherrycreek and Longs soils are deep to a lithic contact. Eastpine, Egyptcreek, Fredonyer, Midpeak, Mineral, Peahke, and Shalrock soils are moderately deep to a lithic contact. Scoap soils have a mollic epipedon 20 to 30 inches thick. Shilling soils are 18 to 27 percent clay in the particle-size control section. Umatilla soils are 25 to 35 percent clay in the particle-size control section. Yellcreek soils have 50 to 80 percent rock fragments in the particle-size control section.
GEOGRAPHIC SETTING: Bearspring soils are on backslopes and footslopes of mountains at elevations of 1,900 to 4,600 feet. These soils formed in colluvium and residuum from granitic rock, with a component of loess and volcanic ash. In glaciated areas these soils also contain a small component of granitic glacial drift. Rock fragments and bedrock consist of granodiorite, quartz monzonite, diorite, porphyritic rhyodacite, and granitic gneiss. Slopes are 20 to 65 percent with primarily west, north, and east-facing aspect. The climate is characterized by warm, dry summers and cold, moist winters. The average annual precipitation is 15 to 24 inches. The mean January temperature is about 23 degrees F, mean July temperature is about 65 degrees F, and the mean annual air temperature is about 43 degrees F. The frost-free season is 90 to 120 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Canteen, Centralpeak, Dinkelman, Ginnis, Kellerbutte, Mineral, Ohscow, Skanid, Spokane, and Tyee soils. Ginnis, Skanid, Spokane, and Tyee soils have a mesic temperature regime. Ginnis soils are on footslopes, backslopes and shoulders of hills. Skanid and Tyee soils are on mountains. Spokane soils are on foothills, mountains and ridgetops. Canteen, Centralpeak, and Dinkelman soils are coarse-loamy. Dinkelman soils are on footslopes and sideslopes of mountains. Mineral soils are 20 to 40 inches to bedrock and are on mountainsides and ridges. Ohscow soils have a 7-to 14-inch volcanic ash mantle. Kellerbutte soils have a volcanic ash mantle which is greater than 14 inches thick. Canteen, Centralpeak, Mineral, and Kellerbutte soils are on similar landscapes as Bearspring soils.
DRAINAGE AND PERMEABILITY: Well drained; slow to rapid runoff; moderate permeability.
USE AND VEGETATION: Timber production, wildlife habitat, watershed, and grazing are the principal uses. The native vegetation is Douglas-fir, ponderosa pine, western larch, white spirea, common snowberry, Saskatoon serviceberry, pinegrass, creambush oceanspray, mallow ninebark, Rocky Mountain maple, Lewis mockorange, Oregon-grape, pachystima, kinnikinnick, fat false-solomons-seal, dwarf rose, and Idaho fescue.
DISTRIBUTION AND EXTENT: North-central Washington. MLRA 43A, 6. The series is of small extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Bozeman, Montana
SERIES ESTABLISHED: Colville Indian Reservation; Ferry and Okanogan Counties, Washington, 1987.
REMARKS: Diagnostic horizons and features recognized in this soil are a mollic epipedon from the mineral surface to 11 inches, a cambic horizon from 12 to 28 inches, and an average of 41 percent angular rock fragments in the particle-size control section.