LOCATION CHAMOKANE          WA+MT
Established Series
Rev. NCD/JJR/JAL
10/2002

CHAMOKANE SERIES


The Chamokane series consists of very deep, somewhat poorly drained soils that formed in alluvium having mixed mineralogy. Chamokane soils are on bottom land and have slopes of 0 to 3 percent. The mean annual precipitation is about 20 inches and the mean annual temperature is about 47 degrees F.

TAXONOMIC CLASS: Coarse-loamy over sandy or sandy-skeletal, mixed, superactive, mesic Fluvaquentic Haploxerolls

TYPICAL PEDON: Chamokane loam - cultivated. (Colors are for dry soil unless otherwise stated.)

Ap--0 to 8 inches; brown (10YR 5/3) loam, dark brown (10YR 3/3) moist; weak fine and medium granular structure; slightly hard, very friable, slightly sticky and slightly plastic; many fine roots; many very fine and fine pores; slightly alkaline (pH 7.8); abrupt smooth boundary. (6 to 10 inches thick)

A--8 to 16 inches; brown (10YR 5/3) loam, dark brown (10YR 3/3) moist; weak medium subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; many fine roots; many very fine and fine pores; moderately alkaline (pH 8.2); clear wavy boundary. (4 to 10 inches thick)

C1--16 to 26 inches; light gray (2.5Y 7/2) loam, light brownish gray (2.5Y 6/2) moist; massive; slightly hard, friable, slightly sticky and slightly plastic; common fine roots; common very fine and fine pores; common fine distinct redox features; neutral (pH 7.2); clear wavy boundary. (6 to 18 inches thick)

C2--26 to 28 inches; light gray (2.5Y 7/2) loam, light brownish gray (2.5Y 6/2) moist; massive; very hard, very firm, slightly sticky and slightly plastic; few fine roots; few fine and medium pores; weakly cemented; neutral (pH 7.0); clear wavy boundary. (2 to 4 inches thick)

IIC3--28 to 60 inches; multicolored stratified gravelly loamy sand; single grain; loose; 20 percent pebbles; neutral (pH 7.0).

TYPE LOCATION: Stevens County, Washington; 1,500 feet west, 50 feet south of the northeast corner of section 30, T. 36 N., R. 39 E.

RANGE IN CHARACTERISTICS: These soils are saturated during the winter and spring. Mean annual soil temperature ranges from 47 degrees to 49 degrees F. Organic carbon decreases irregularly with increasing depth. The upper part of the particle-size control section is loam or fine sandy loam with lenses of clay loam and loamy sand in some pedons. It has less than 18 percent clay. The depth to the gravelly sandy IIC horizon ranges from 24 to 40 inches. The reaction is neutral to moderately alkaline.

The A horizon has value of 4 or 5 dry, 2 or 3 moist, and chroma of 2 or 3 dry or moist. The A horizon is calcareous in some pedons.

The C horizon has value of 6 or 7 dry and 5 or 6 moist. It is loam, heavy loam, fine sandy loam and has lenses of clay loam in some pedons. It has 0 to 15 percent pebbles.

The IIC horizon is gravelly loamy sand or gravelly sand. Some pedons have thin lenses of volcanic ash, loam, or sandy loams. This horizon has 15 to 25 percent pebbles.

COMPETING SERIES: This is the Balm series. Balm soils are calcareous in the upper part of the control section and have very gravelly sand in the lower part of the control section.

GEOGRAPHIC SETTING: These soils are on bottom land adjacent to streams at elevations of 1,600 to 3,000 feet. Slopes are 0 to 3 percent. These soils formed in alluvium. The summers are warm and dry and the winters are moist and cold. Mean annual precipitation is 18 to 22 inches. Mean January temperature is about 26 degrees F., mean July temperature is about 68 degrees F., mean annual temperature is about 47 degrees F., and the average frost-free season is 90 to 120 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Bonner, Eloika, Narcisse, and Springdale soils. Bonner and Springdale soils have more than 35 percent coarse fragments in the lower part of the control section. Eloika soils have more than 60 percent volcanic ash in the upper part of the control section. Narcisse soils have a mollic epipedon more than 20 inches thick.

DRAINAGE AND PERMEABILITY: Somewhat poorly drained; very slow runoff; moderate permeability to about 28 inches and very rapid below. Subject to occasional stream overflow.

USE AND VEGETATION: Cropland and grazed woodland; native vegetation is Douglas-fir, western redcedar, aspen, red alder, Engelmann spruce, western larch, grand fir, willow, shrubs, and grasses.

DISTRIBUTION AND EXTENT: Northeastern Washington. The series is small in extent.

MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Bozeman, Montana

SERIES ESTABLISHED: Stevens County, Washington, 1913.


National Cooperative Soil Survey
U.S.A.