LOCATION BRAZLAN WAEstablished Series
TAXONOMIC CLASS: Loamy-skeletal, mixed, superactive, mesic Vitrandic Durixerolls
TYPICAL PEDON: Brazlan cobbly ashy fine sandy loam - cropland, on a 3 percent slope at 2,500 feet elevation. (Colors are for dry soil unless otherwise stated. All textures are apparent field textures.)
Ap--0 to 5 inches; grayish brown (10YR 5/2) cobbly ashy fine sandy loam, very dark grayish brown (10YR 3/2) moist; moderate fine and medium platy structure; soft, very friable, nonsticky and slightly plastic; many very fine and few fine roots; common very fine tubular pores; 15 percent gravel, 10 percent cobbles and 1 percent surface cobbles; 3 percent ash 0.5 to 2.0 mm. in diameter; neutral (pH 7.0); clear wavy boundary. (4 to 6 inches thick)
AB--5 to 13 inches; brown (10YR 5/3) very cobbly ashy loam, dark brown (10YR 3/3) moist; moderate medium subangular blocky structure; slightly hard, firm, slightly sticky and slightly plastic; common very fine roots; common fine tubular and irregular pores; 20 percent gravel and 20 percent cobbles; 3 percent ash 0.5 to 2.0 mm. in diameter; neutral (pH 7.2); abrupt wavy boundary. (6 to 10 inches thick)
2Bw--13 to 20 inches; gray (10YR 5/1) very gravelly sandy loam, very dark gray (10YR 3/1) moist; massive; slightly hard, friable, nonsticky and nonplastic; common very fine roots; common fine irregular pores; 35 percent gravel and 10 percent cobbles; slightly alkaline (pH 7.4); abrupt wavy boundary. (6 to 12 inches thick)
2Bqm--20 to 25 inches; dark gray (10YR 4/1) weakly cemented duripan crushes to gravelly coarse sandy loam, very dark gray (10YR 3/1) moist; many distinct grayish brown 2.5Y 5/2 silica coatings less than 1 mm thick covering the upper duripan surface; massive, very hard, very firm, nonsticky and nonplastic; few fine tubular pores; 20 percent gravel and 10 percent cobbles; slightly alkaline (pH 7.4); abrupt wavy boundary. (4 to 10 inches thick)
3R--25 inches; basalt
TYPE LOCATION: Douglas County, Washington, about 4 miles northwest of Elbow Lake; approximately 2,800 feet east and 1,200 feet north of the southwest corner section 31, T.30N. R.29E. (Latitude 48 degrees 03 minutes 38 seconds N, Longitude 119 degrees 12 minutes 26 seconds W)
RANGE IN CHARACTERISTICS: The mean annual soil temperature is 49 to 51 degrees F. These soils are usually moist but are dry in the moisture control section for 90 to 105 consecutive days after the summer solstice. The mollic epipedon is 10 to 14 inches thick and has an estimated moist bulk density of 1.10 to 1.35 g/cc, volcanic glass content of 30 to 60 percent, including 2 to 15 percent sand-size pumice, 0.5 to 2.0 mm. in diameter, acid-oxalate extractable aluminum plus one-half of the acid oxalate extractable iron of 0.15 to 0.40 percent, 15-bar water retention of 5 to 10 percent, and 5 to 14 percent apparent field textured clay content. The particle-size control section contains 35 to 55 percent rock fragments. Depth to duripan is 20 to 36 inches and basalt bedrock is at 24 to 40 inches.
The A horizon has a value of 4 or 5 dry and 2 or 3 moist. The chroma is 1 to 3 dry or moist.
The AB horizon has hue of 10YR or 2.5Y, value of 5 or 6 dry, 3 or 4 moist, chroma of 2 to 4 dry and 2 or 3 moist. Texture is very cobbly ashy loam, very gravelly ashy sandy loam or very gravelly ashy loam. Reaction is neutral or slightly alkaline.
The 2Bw horizon has hue of 2.5Y, 5Y or 10YR. The value is 4 to 6 dry and 3 or 4 moist. The chroma is 1 to 3 dry and 1 or 2 moist. Texture is very gravelly sandy loam or very gravelly loam. The apparent field clay content is 5 to 10 percent. Reaction is slightly alkaline or moderately alkaline.
The 2Bqm horizon has hue of 7.5YR to 2.5Y, value of 3 or 4 moist or dry. It is weakly or moderately cemented. It is fine sandy loam, sandy loam, coarse sandy loam or loam with 10 to 35 percent gravel, 0 to 20 percent cobbles and 0 to 10 percent stones. It is slightly to moderately alkaline.
COMPETING SERIES: This is the Townsend series. Townsend soils have a mollic epipedon 20 to 30 inches thick and depth to weakly cemented basal till is 30 to 40 inches.
GEOGRAPHIC SETTING: Brazlan soils are on glaciated plateaus. Slopes are 0 to 50 percent. These soils formed in glacial till mixed with loess and volcanic ash over basalt. Elevations are 1,700 to 3,200 feet. Climate is characterized by warm, dry summers and cool, moist winters. Average annual precipitation is 12 to 15 inches. Average January temperature is about 26 degrees F. Average July temperature is about 70 degrees F. Average annual temperature is 47 to 49 degrees F. Frost-free season is 110 to 165 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Dezellem, Timentwa, and Siweeka soils, all are on upland till plains. Dezellem soils are very deep. Timentwa soils have less than 35 percent rock fragments in the particle-size control section and are deep to cemented duripan.
DRAINAGE AND PERMEABILITY: Well drained; very slow to rapid runoff; moderately rapid permeability above the duripan.
USE AND VEGETATION: These soils are used mainly for crop production. Dryland wheat and barley are the principal crops. Small areas are used for livestock grazing and wildlife habitat. Potential native vegetation is bluebunch wheatgrass, Sandberg bluegrass, threetip sagebrush and Wyoming big sagebrush.
DISTRIBUTION AND EXTENT: Douglas County, Washington.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Portland, Oregon
SERIES ESTABLISHED: Douglas County, Washington, 1998.
REMARKS: Diagnostic horizons and features recognized in this pedon are a mollic epipedon from the surface to 13 inches, with an estimated 30 to 60 percent volcanic glass, and a cambic horizon from 13 to 20 inches over a weakly cemented duripan at 20 inches. The particle-size control section is from 10 to 20 inches (part of the AB horizon and all of the 2Bw horizon).
ADDITIONAL DATA: Partial lab data is available on another pedon from the National Soil Survey Laboratory in Lincoln, Nebraska, pedon number 90P0350.