LOCATION VAN NOSTERN WAEstablished Series
TAXONOMIC CLASS: Fine-silty, mixed, superactive, mesic Pachic Argixerolls
TYPICAL PEDON: Van Nostern silt loam - rangeland on a 3 percent southeast-facing slope at an elevation of 3,120 feet. (Colors are for dry soil unless otherwise noted.)
A1--0 to 6 inches; brown (10YR 5/3) silt loam, very dark grayish brown (10YR 3/2) moist; weak very fine and fine granular structure; soft, very friable, nonsticky and nonplastic; many very fine roots; common very fine irregular pores; neutral (pH 6.8); clear smooth boundary. (2 to 6 inches thick)
A2--6 to 11 inches; grayish brown (10YR 5/2) silt loam, very dark grayish brown (10YR 3/2) moist; moderate fine and medium subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; many very fine roots; common very fine tubular and few very fine irregular pores; neutral (pH 6.8); clear smooth boundary. (5 to 11 inches thick)
BAt--11 to 19 inches; brown (10YR 5/3) silt loam, dark brown (10YR 3/3) moist; moderate coarse prismatic structure parting to strong fine and medium subangular blocky; slightly hard, friable, slightly sticky and slightly plastic; common very fine roots; many very fine and fine tubular pores; common faint clay films on ped faces; neutral (pH 6.6); clear wavy boundary. (7 to 12 inches thick)
Bt1--19 to 28 inches; brown (10YR 5/3) silt loam, dark brown (10YR 3/3) moist; moderate medium prismatic structure parting to strong fine and medium subangular blocky; hard, firm, moderately sticky and moderately plastic; common very fine roots; many very fine and fine tubular pores; common faint clay films on ped faces; neutral (pH 6.6); clear smooth boundary. (4 to 10 inches thick)
Bt2--28 to 34 inches; pale brown (10YR 6/3) silt loam, brown (10YR 4/3) moist; moderate medium subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; few very fine roots; common very fine tubular pores; few faint clay films on ped faces; 5 percent gravel; neutral (pH 6.6); abrupt wavy boundary. (2 to 8 inches thick)
2R--34 inches; basalt.
TYPE LOCATION: Klickitat County, Washington, 1 mile west of Cleveland, about 20 feet south and 2,000 feet east of the northwest corner, section 36, T 6N., R. 19 E.
RANGE IN CHARACTERISTICS: These soils are usually moist, but are dry in the moisture control section for 90 to 105 consecutive days following the summer solstice. The mean annual soil temperature is 48 to 52 degrees F. Depth to bedrock is 20 to 40 inches. Clay content in the particle-size control section averages from 18 to 27 percent. The mollic epipedon is 20 to 30 inches thick.
The A horizon has value of 4 or 5 dry, 2 or 3 moist and chroma of 2 or 3 dry and moist. Reaction is slightly acid or neutral.
The BAt horizon has value of 4 or 5 dry and chroma of 2 or 3 dry and moist. It has prismatic or subangular blocky structure.
The Bt horizon has value of 4 to 6 dry, 3 or 4 moist and chroma of 3 or 4 dry and moist. It has prismatic or subangular blocky structure. Reaction is neutral or slightly alkaline. It contains 0 to 5 percent gravel in the lower part of horizon.
COMPETING SERIES: These are the Hanning, Hendricks, and Mohler series. Hanning soils are more than 40 inches deep. Hendricks soils have argillic horizons with 27 to 35 percent clay and are dry for 45 to 60 consecutive days following the summer solstice. Mohler soils are more than 60 inches deep, have argillic horizons with 27 to 35 percent clay, and are dry for 75 to 90 consecutive days following the summer solstice..
GEOGRAPHIC SETTING: Van Nostern soils are on plateaus at elevations of 2,200 to 3,500 feet. Slopes are 0 to 30 percent. They formed in loess over basalt. Summers are warm and dry; winters are cool and moist. The mean annual precipitation is 12 to 15 inches. The average January temperature is 26 degrees F. and the average July temperature is 65 degrees F. The mean annual temperature is 46 to 49 degrees F. The frost-free season is 110 to 165 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are Bakeoven, Bickleton, Morrow and Onyx soils. Bakeoven soils are 4 to 12 inches deep to bedrock and are on uplands. Bickleton soils are fine-loamy, more than 40 inches deep to bedrock, have free carbonates within 40 inches, and are on uplands. Morrow soils have secondary carbonates at 10 to 20 inches and are on uplands and plateaus. Onyx soils are coarse-silty, more than 60 inches to bedrock, and are on flood plains and fans.
DRAINAGE AND PERMEABILITY: Well drained; slow to medium runoff; moderate permeability.
USE AND VEGETATION: These soils are used for cropland, pasture, and rangeland. Native vegetation is Idaho fescue, bluebunch wheatgrass, Sandberg bluegrass, arrowleaf balsamroot, eriogonum, hawksbeard, and antelope bitterbrush.
DISTRIBUTION AND EXTENT: Central and south-central, Washington. MLRA 8. The series is moderately extensive.
MLRA OFFICE RESPONSIBLE: Portland, Oregon
SERIES ESTABLISHED: Douglas County, Washington, 1998.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
Mollic epipedon - the zone from 0 to 28 inches
Argillic horizon - the zone from 11 to 34 inches
Lithic contact - the zone beginning at 34 inches
Particle-size control section - the zone from 11 to 31 inches