LOCATION OJIBWAY WAEstablished Series
TAXONOMIC CLASS: Coarse-loamy, isotic, frigid Vitrandic Dystroxerepts
TYPICAL PEDON: Ojibway gravelly loam-woodland. (Colors are for dry soil unless otherwise stated.)
0e--2 inches to 0; fresh and partly decomposed organic litter composed of needles, leaves, bark, moss, and twigs; abrupt smooth boundary. (1 to 3 inches thick)
A1--0 to 1/2 inch; light gray (2.5Y 7/2) very fine sandy loam (volcanic ash), grayish brown (2.5Y 5/2) moist; weak very fine and fine subangular blocky structure; soft very friable, nonsticky and nonplastic; common very fine, fine, medium, and coarse roots; neutral (pH 6.8); abrupt smooth boundary. (0 to 1 inch thick)
A2--1/2 to 5 inches; dark brown (7.5YR 4/4) gravelly loam, dark reddish brown (5YR 3/2) moist; weak medium granular and weak fine subangular blocky structure; slightly hard, friable, nonsticky and slightly plastic; common very fine, fine, medium, and coarse roots; 25 percent angular pebbles and 5 percent angular cobbles; NaF pH 9.9; slightly acid (pH 6.4); clear wavy boundary. (5 to 7 inches thick)
Bw1--5 to 11 inches; dark brown (7.5YR 4/4) very gravelly loam, dark reddish brown (5YR 3/4) moist; weak fine subangular blocky structure; slightly hard, friable, nonsticky and slightly plastic; common very fine, fine, medium, and coarse roots; 35 percent angular pebbles, 10 percent angular cobbles, and 5 percent angular and subangular saprolitic fragments; NaF pH 9.6; slightly acid (pH 6.4); clear wavy boundary. (5 to 7 inches thick)
Bw2--11 to 17 inches; strong brown (7.5YR 5/6) gravelly loam, dark brown (7.5YR 4/4) moist; moderate fine subangular blocky and moderate medium and coarse granular structure; hard, firm, nonsticky and slightly plastic; common very fine and fine roots; 20 percent angular pebbles and 10 percent angular cobbles, and 25 percent angular and subangular saprolitic fragments; NaF pH 9.2; slightly acid (pH 6.2); clear wavy boundary. (5 to 7 inches thick)
Bw3--17 to 23 inches; strong brown (7.5YR 5/6) gravelly sandy loam, dark brown (7.5YR 4/4) moist; moderate fine subangular blocky and moderate medium and coarse granular structure; hard, firm, nonsticky and slightly plastic; few very fine, fine, and medium roots; 15 percent angular pebbles, 5 percent cobbles, and 40 percent angular and subangular saprolitic fragments; NaF pH 9.2; moderately acid (pH 6.0) abrupt wavy boundary. (5 to 6 inches thick)
Cr--23 inches; weathered amphibolite; few very fine, fine, and medium roots and many thick clay films oriented along fracture planes.
TYPE LOCATION: Pend Oreille County, Washington; 600 feet west and 350 feet north of the southeast corner, sec. 15, T. 32N., R. 45 E.
RANGE IN CHARACTERISTICS: Depth to a paralithic contact is 20 to 40 inches. The mean annual soil temperature at 20 inches ranges from 45 to 47 degrees F. These soils are dry in the moisture control section for 45 to 60 consecutive days following the summer solstice. The particle-size control section averages 25 to 45 percent sand and includes increasing percentages of saprolitic material with depth with percentages, ranging from 5 to 40 percent. The hard rock, mostly quartzitic and amphibolite, averages 20 to 35 percent in the control section, but ranges to 45 percent in some subhorizons.
The A1 horizon, when present, has value of 6 or 7 dry, 5 or 6 moist, and chroma of 1 or 2 moist and dry.
The A2 horizon has hue of 7.5YR or 5YR, value of 3 or 4 dry, and chroma of 3 or 4 dry, 2 or 3 moist. Hard rock fragments range from 20 to 50 percent and include pebbles and cobbles; soft fragments range from 5 to 20 percent.
The Bw horizon has hue of 5YR or 7.5YR, value of 4 or 5 dry, 3 or 4 moist, and chroma of 4 to 6 moist and dry. The texture of the fine earth fraction is loam or sandy loam. It has 15 to 35 percent hard pebbles and 5 to 15 percent hard cobbles in the upper part and 15 to 30 percent hard pebbles and 0 to 10 percent hard cobbles in the lower part. It has 5 to 40 percent soft saprolite fragments with the larger amounts in the lower part. It is slightly acid or moderately acid.
COMPETING SERIES: This is the Switchback series. Similar series in other families are Aits, Apex, Canteen, Centralpeak, Leadpoint, Moonville, Moscow, Moso, Osborn, Roslyn, Volperie, and Waits series. Switchback soils are dry for 75 to 90 consecutive days. Aits, Apex, Canteen, Moonville, Moso, Roslyn, and Waits soils lack bedrock within depth of 40 inches. Centralpeak soils are dry for 60 to 75 consecutive days and have hue of 2.5Y or 10YR in the 2Bw horizon. Leadpoint soils are neutral or mildly alkaline and have colors with a value of 2 or 3 moist, 2 to 5 dry, and chroma of 0 or 1 throughout. Moscow and Moso soils have a lithologic discontinuity in the control section and the lower part of the control section has hue of 10YR or 2.5Y. Osborn soils have a 7 or 8 inch thick volcanic ash mantle and are 45 to 70 percent sand in the particle-size control section. Volperie soils are dry 60 to 75 days, are 5 to 15 percent mica in the particle-size control section, and have a 7 to 13 inch thick volcanic ash mantle.
GEOGRAPHIC SETTING: Ojibway soils are on mountains and have slopes of 30 to 65 percent. These soils formed in mixed colluvium and residual material mainly from amphibolite with a admixture of volcanic ash and loess. Elevations are 2,600 to 4,750 feet. The average annual temperature ranges from 43 to 45 degrees F. The average annual precipitation ranges from 30 to 45 inches and the frost-free season ranges from 90 to 110 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Bonner, Hartill, Huckleberry, Rufus, and Raisio soils. Bonner soils are coarse-loamy over sandy or sandy-skeletal. Hartill soils are loamy-skeletal. Huckleberry soils are ashy and cryic. Rufus and Raisio soils are mesic and loamy-skeletal.
DRAINAGE AND PERMEABILITY: Well drained; slow to rapid runoff; permeability is moderate.
USE AND VEGETATION: Grazable woodland, wildlife habitat, watershed, and recreation. Native vegetation includes Douglas-fir, grand fir, western larch, ponderosa pine, western hemlock, and western redcedar with an understory of common snowberry, common yarrow, starry false -Solomons-seal, Oregon-grape, and serviceberry.
DISTRIBUTION AND EXTENT: Mountainous area of northeastern Washington (Pend Oreille County) and possibly northern Idaho. Series is of small extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Bozeman, Montana
SERIES ESTABLISHED: Pend Oreille County Area, Washington, 1981.
REMARKS: Diagnostic horizons and features recognized in this pedon are: Albic horizon from the mineral surface to 1/2 inch Cambic horizon from 1/2 inch to 23 inches Lithic contact at 23 inches. The upper 11 inches of the mineral soil is estimated to have volcanic glass content of 5 to 20 percent and acid-oxalate extractable aluminum plus one-half of the acid-oxalate extractable iron of 0.4 to 1.0 percent. This description reflects a change in classification due to Andisols Order from Coarse-loamy, mixed, frigid Andic Xerochrepts to Coarse-loamy, mixed, frigid Vitrandic Xerochrepts.