LOCATION BENGE              WA
Established Series


The soils of the Benge series are deep, well drained soils formed in glacial outwash with a mixture of loess in the upper part. They are on terraces. The mean annual precipitation is about 14 inches and the mean annual air temperature is about 52 degrees F.

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

TYPIFYING PEDON: Benge silt loam, grassland. (Colors are for dry soil unless otherwise noted.)

A11--0 to 6 inches; dark grayish brown (10YR 4/2) silt loam, very dark brown (10YR 2/2) when moist; weak fine and medium granular structure; soft, very friable, slightly sticky and slightly plastic; many roots; mildly alkaline (pH 7.6); clear, wavy boundary. 5 to 7 inches thick.

A12--6 to 10 inches; grayish brown (10YR 5/2) silt loam, very dark grayish brown (10YR 3/2) when moist; weak, fine and medium, granular structure; slightly hard, very friable, slightly sticky and slightly plastic; common roots; mildly alkaline (pH 7.6); clear, wavy boundary. 4 to 7 inches thick.

B2--10 to 16 inches; brown (10YR 5/3) silt loam, dark brown (10YR 3/3) when moist; weak, fine, subangular blocky structure; slightly hard, very friable, slightly sticky and slightly plastic; common roots; common very fine tubular pores; mildly alkaline (pH 7.8); clear, wavy boundary. 6 to 18 inches thick.

C1--16 to 26 inches; brown (10YR 5/3) gravelly loam, dark brown (10YR 4/3) when moist; massive; soft, very friable; common roots; mildly alkaline (pH 7.8); clear, wavy boundary. 4 to 12 inches thick.

IIC2--26 to 60 inches; basalt gravel and sand; some lime coatings on underside of pebbles; moderately alkaline.

TYPE LOCATION: Adams County, Washington; 2,640 feet east and 1,650 feet south of the NW corner of sec. 35, T.19N., R.36E.

RANGE IN CHARACTERISTICS: The sola range from 15 to 24 inches thick. The depth to the discontinuity and to lime if present is 24 to 36 inches and ranges from 24 to 40 inches. The mollic epipedon is 9 to 14 inches thick. The mean annual soil temperature at depth of 20 inches is 50 degrees to 56 degrees F. These soils are usually moist, but are dry in all parts between depths of 8 to 25 inches for 70 to 90 consecutive days. The upper part of the control section averages less than 10 percent rock fragments and has less than 50 percent fine or coarser sand.

The A horizon has value of 4 or 5 dry and 2 or 3 moist. It has weak granular or blocky structure and is neutral to mildly alkaline.

The B horizon has value of 4 or 5 dry. It is silt loam or loam. This horizon has weak subangular blocky or weak prismatic structure.

The C1 horizon has value of 5 or 6 dry, and 3 or 4 moist. It is gravelly loam or gravelly silt loam. This horizon is mildly or moderately alkaline. The IIC horizon is dominantly gravel with sand filling the voids larger than 1 mm.

COMPETING SERIES AND THEIR DIFFERENTIAE: These are the Beckley, Cheney, Chewelah and Haley series. Beckley and Haley soils have a coarse sandy loam or fine sandy loam control section. Also, Haley soils lack rock fragments. Cheney soils have a chroma of 4 in the control section. Chewelah soils are calcareous in all parts of the solum.

GEOGRAPHIC SETTING: Benge soils are on nearly level to very steep terraces at elevations of 600 to 2,500 feet. The soils formed in glacial outwash materials with a mixture of loess in the upper part. Summers are hot and dry and winters are cool and moist. Mean annual precipitation is 12 to 16 inches. Mean July temperature is 73 degrees F.; mean January temperature is 32 degrees F.; mean annual temperature is 52 degrees F., and the frost-free season is 135 to 180 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Anders, Chard, Henningson, Quincy, and Weirman soils. Anders soils have basalt bedrock at depths of 20 to 40 inches. Chard soils are nonskeletal. Henningson, Quincy, and Weirman soils are coarse textured throughout the control section and Henningson soils have an aquic moisture regime.

DRAINAGE AND PERMEABILITY: Well drained; slow to rapid runoff; moderate permeability above the IIC horizon; very rapid permeability in the IIC horizon.

USE AND VEGETATION: Used for growing orchards, small grains, hay and pasture, mostly under irrigation; and are also used for range, recreation, wildlife habitat and watershed protection. Native vegetation is mostly bluebunch wheatgrass, Sandberg bluegrass, and cheatgrass.

DISTRIBUTION AND EXTENT: Southeastern Washington. The series is of moderate extent.


SERIES ESTABLISHED: Adams County, Washington, 1970.

REMARKS: These soils were formerly classified as Chestnut soils.

ADDITIONAL DATA: Riverside Lab. Nos. 61253-61257 and 61258-61263.

National Cooperative Soil Survey
U. S. A.