LOCATION BALDKNOB WAEstablished Series
The Baldknob series consists of shallow, well drained soils formed in colluvium and residuum from rhyodacite and andesite with a minor component of glacial till. The upper part also has an admixture of volcanic ash and loess. These soils are on summits, shoulders, and backslopes of glacially scoured foothills and mountains. Slopes are 5 to 65 percent. The average annual precipitation is about 17 inches, and the mean annual air temperature is about 43 degrees F.
TAXONOMIC CLASS: Loamy-skeletal, mixed, superactive, frigid Lithic Ultic Haploxerolls
TYPICAL PEDON: Baldknob very stony loam - on a 55 percent south facing slope under native grasses and shrubs, at an elevation of 4,000 feet. (Colors are for dry soil unless otherwise noted.)
A--0 to 4 inches; brown (10YR 5/3) very stony loam, very dark grayish brown (10YR 3/2) moist; moderate fine subangular blocky structure; soft, very friable, slightly sticky, nonplastic; common very fine and fine roots; 30 percent pebbles, 5 percent cobbles, 10 percent surface stones; slightly acid (pH 6.2); clear wavy boundary. (4 to 10 inches thick)
Bw1--4 to 9 inches; brown (10YR 5/3) very gravelly loam, dark brown (10YR 3/3) moist; moderate fine subangular blocky structure; soft, very friable, slightly sticky, slightly plastic; common very fine and fine roots; 40 percent pebbles, 15 percent cobbles; slightly acid (pH 6.2); gradual wavy boundary. (3 to 8 inches thick)
Bw2--9 to 14 inches; yellowish brown (10YR 5/4) extremely gravelly loam, brown (7.5YR 4/3) moist; weak fine subangular blocky structure; soft, very friable, slightly sticky, slightly plastic; few fine roots; 45 percent pebbles, 20 percent cobbles; slightly acid (pH 6.2); abrupt wavy boundary. (0 to 9 inches thick)
R--14 inches; hard rhyodacite.
TYPE LOCATION: Colville Indian Reservation; Ferry County, Washington; about 15 miles northeast of the town of Nespelem; 2,000 feet north, 400 feet east of the southwest corner of sec. 13, T. 33 N., R. 31 E., W.M.
RANGE IN CHARACTERISTICS: Depth to a lithic contact ranges from 10 to 20 inches. The mean annual soil temperature at the lithic contact ranges from 44 to 46 degrees F. These soils are usually moist but are dry between a depth of 8 inches and the lithic contact for 60 to 75 consecutive days following the summer solstice. The mollic epipedon is 7 to 12 inches thick. The particle-size control section is 8 to 18 percent clay and 35 to 70 percent rock fragments by weighted average. Reaction is slightly acid or neutral throughout.
The A horizon has hue of 7.5YR or l0YR, value of 4 or 5 dry, 2 or 3 moist; and chroma of 2 through 4 dry, 2 or 3 moist. It is l0 to 30 percent pebbles, 0 to 20 percent cobbles, and stones may cover up to l5 percent of the surface.
The Bw horizon has hue of 7.5YR or 10YR, value of 5 or 6 dry, 3 or 4 moist, and chroma of 3 or 4 dry or moist. It is very gravelly, extremely gravelly, very cobbly, or extremely cobbly and is l5 to 50 percent pebbles, 5 to 30 percent cobbles, and 0 to l5 percent stones.
COMPETING SERIES: These are the Blewett (T), Chumstick, Franktown, Laycock, and Logdell series. Blewett soils are 5 to 20 percent soft sandstone in the particle-size control section. Chumstick soils are 35 to 70 percent schist and gneiss rock fragments which are high in quartz and feldspars, and the fine-earth fraction is sandy loam or fine sandy loam. Franktown soils lack a Bw horizon and have a C horizon. Laycock and Logdell soils lack a Bw horizon and average 18 to 30 percent clay in the fine-earth fraction of the particle-size control section.
GEOGRAPHIC SETTING: Baldknob soils are on summits, shoulders, and backslopes of glacially scoured foothills and mountains. These soils formed mainly in colluvium and residuum from rhyodacite and andesite, with a minor component of glacial till. The upper part of the soil also contains an admixture of volcanic ash and loess. Slopes are 5 to 65 percent. Elevations range from 2,200 to 5,500 feet. The climate is characterized by warm, dry summers and cold, moist winters. The average annual precipitation is 14 to 22 inches. The mean January temperature is about 23 degrees F, the mean July temperature is about 64 degrees F, and the mean annual air temperature is about 43 degrees F. The frost-free period is 90 to 120 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Inkler, Johntom, Nevine, Northstar, and Thout soils. Inkler and Nevine soils are deep. Johntom soils are mesic. Northstar soils are 20 to 40 inches deep and mesic. Thout soils are 20 to 40 inches deep.
DRAINAGE AND PERMEABILITY: Well drained; moderate permeability; slow to very rapid runoff.
USE AND VEGETATION: Principal uses are livestock grazing and wildlife habitat. Native vegetation includes bluebunch wheatgrass, Idaho fescue, arrowleaf balsamroot, lupine, common yarrow, Wyeth eriogonum, common snowberry, and Saskatoon serviceberry. Tree species are widely scattered, stunted Douglas-fir and ponderosa pine.
DISTRIBUTION AND EXTENT: Northcentral Washington. The series is of moderate extent.
MLRA OFFICE RESPONSIBLE: Portland, Oregon
SERIES ESTABLISHED: Ferry County (Colville Indian Reservation), Washington, 1987.
REMARKS: Diagnostic horizons and features recognized in this soil are a mollic epipedon from the surface to 9 inches, a cambic horizon from 9 to 14 inches, and a lithic contact at 14 inches. The particle-size control section is from the surface to 14 inches in this pedon, and it is 53 percent rock fragments by weighted average.