LOCATION AARUP WAEstablished Series
TAXONOMIC CLASS: Ashy, glassy, mesic, shallow Vitritorrandic Durixerolls
TYPICAL PEDON: Aarup ashy fine sandy loam- cropland, on a 1 percent slope at an elevation of 2,430 feet. (Colors are for dry soil unless otherwise stated. All textures are apparent field textures.)
Ap1--0 to 7 inches; brown (10YR 5/3) ashy fine sandy loam, very dark grayish brown (10YR 3/2) moist; weak fine granular structure; soft, very friable, nonsticky and slightly plastic, common very fine and fine roots; few very fine interstitial and tubular pores; 15 percent sand-size pumice less than 2.0mm in diameter; neutral (pH 6.6); clear smooth boundary. (0 to 8 inches thick)
Ap2--7 to 9 inches; brown (10YR 5/3) ashy fine sandy loam, very dark grayish brown (10YR 3/2) moist; weak medium granular structure; slightly hard, friable, nonsticky and slightly plastic; common very fine and fine roots; common fine and very fine tubular and interstitial pores; 20 percent sand-size pumice less than 2.0mm in diameter; neutral (pH 7.0); clear wavy boundary. (0 to 7 inches thick)
Bw--9 to 16 inches; brown (10YR 5/3) ashy very fine sandy loam, dark brown (10YR 3/3) moist; weak medium subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; few fine roots; few fine tubular and interstitial pores; 10 percent sand-size pumice less than 2.0 mm in diameter; 5 percent basalt gravel and duripan fragments; slightly alkaline (pH 7.6); abrupt wavy boundary. (4 to 8 inches thick)
2Bkqm--16 to 26 inches; indurated lime-silica cemented duripan; very pale brown (10YR 8/2), light yellowish brown (10YR 6/4) moist; violently effervescent, abrupt wavy boundary. (4 to 12 inches thick)
3R--26 inches; basalt.
TYPE LOCATION: Douglas County, Washington; about 3/4 miles west and 1/4 miles north of the Farmer Elevators; 800 feet north and 250 feet east of the southwest corner section 33, T.25N., R.24E. (Latitude 47 degrees 36 minutes 58 seconds N, Longitude 119 degrees 49 minutes 54 seconds W)
RANGE IN CHARACTERISTICS: The mean annual soil temperature is 50 to 52 degrees F. These soils are usually dry in the moisture control section for 105 to 120 consecutive days when the soil temperature at duripan contact is above 40 F. The mollic epipedon is 4 to 12 inches thick. The particle-size control section has an estimated moist bulk density of 1.10 to 1.35 g/cc, volcanic glass content of 30 to 60 percent, including 10 to 30 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 for air dried samples, and 15 percent fine sand or coarser including pan fragments greater than 2.0mm, and field estimate of 4 to 10 percent clay. Depth to indurated duripan ranges from 4 to 20 inches. Basalt bedrock is at 20 to 40 inches.
The Ap horizon has a chroma of 2 or 3 moist. Duripan fragments range from 0 to 15 percent.
The Bw horizon has value of 5 or 6 dry, 3 or 4 moist. It is a ashy very fine sandy loam, ashy fine sandy loam, or ashy sandy loam. Reaction is slightly alkaline to moderately alkaline. Basalt gravel and duripan fragments range from 0 to 15 percent and 0 to 3 percent cobbles. Some pedons have a Bk horizon.
COMPETING SERIES: There are no competing series.
GEOGRAPHIC SETTING: Aarup soils are on upland summits, dissected hill slopes and toe slopes on basalt plateaus. Slopes are 0 to 15 percent. They formed in mixed loess, volcanic ash and pumice from Glacier Peak over an indurated duripan. Elevation are 1,900 to 2,800 feet. These soils are in a semiarid climate with warm, dry summers and cool, moist winters. The mean annual precipitation is 9 to 12 inches. Average January temperature is about 27 degrees F., average July temperature is about 71 degrees F., and average annual temperature is 48 to 50 degrees F. Frost-free season is 130 to 180 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Deercut, Corbaley, Slusser, Sprauer, Toler and Whiteye soils. All of these soils are on uplands. Deercut and Sprauer soils are 20 to 40 inches to duripan. Corbaley soils are 10 to 20 inches to basalt. Slusser soils are deep. Toler soils are 20 to 40 inches to basalt. Whiteye soils have an argillic horizon.
DRAINAGE AND PERMEABILITY: Well drained; slow to medium runoff; moderate permeability above the duripan, and very slow within the duripan.
USE AND VEGETATION: These soils are mainly used for cropland. Wheat and barley are the principal crops. Small areas are used for livestock production. Native vegetation is bluebunch wheatgrass, Sandberg bluegrass, lupine and Wyoming big sagebrush.
DISTRIBUTION AND EXTENT: North Central Washington. The series is of small extent.
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 9 inches, a cambic horizon from 9 to 16 inches, and an indurated duripan at 16 inches. Sand-size pumice in the 0 to 16 inch zone is 10 to 20 percent. The particle size control section is a zone from 10 to 16 inches (the Bw horizon).