LOCATION EMDENT WAEstablished Series
TAXONOMIC CLASS: Ashy, glassy, calcareous, mesic Typic Vitraquands
TYPICAL PEDON: Emdent silt loam - grassland. (Colors are for moist soil unless otherwise stated.)
A1kzn--0 to 5 inches; very dark gray (10YR 3/1) ashy silt loam, gray (10YR 5/1) dry; moderate thin platy structure; slightly hard, friable, slightly sticky and slightly plastic; many roots; violently effervescent; very strongly alkaline (pH 9.2); abrupt smooth boundary. (4 to 6 inches thick)
A2kzn--5 to 16 inches; very dark gray (10YR 3/1) ashy silt loam, gray (10YR 5/1) dry; weak medium subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; common roots; common fine and very fine tubular pores; violently effervescent; very strongly alkaline (pH 9.2); gradual wavy boundary. (4 to 14 inches thick)
Bkzn--16 to 21 inches; dark gray (10YR 4/1) ashy silt loam, gray (10YR 6/1) dry; massive; slightly hard, friable, slightly sticky and slightly plastic; few roots; many very fine tubular pores; violently effervescent; moderately alkaline (pH 8.4); gradual wavy boundary. (4 to 10 inches thick)
C1--21 to 26 inches; grayish brown (10YR 5/2) ashy silt loam, light gray (10YR 7/1) dry; massive; slightly hard, friable, slightly sticky and slightly plastic; few roots; many very fine tubular pores; slightly effervescent; moderately alkaline (pH 8.2); gradual wavy boundary. (4 to 15 inches thick)
C2--26 to 52 inches; light brownish gray (10YR 6/2) ashy very fine sandy loam, white (10YR 8/1) dry; massive; soft, very friable, nonsticky and nonplastic; few roots; few very fine tubular pores; slightly effervescent; moderately alkaline (pH 8.0); clear wavy boundary. (20 to 40 inches thick)
C3--52 to 60 inches; dark gray (10YR 4/1) ashy silt loam, gray (10YR 6/1) dry; massive; slightly hard, friable, slightly sticky and slightly plastic; few very fine pores; non-effervescent; moderately alkaline (pH 8.4)
TYPE LOCATION: Adams County, Washington, about 8 miles north of the town of Benge; 1,000 feet north of southeast corner of section 30, T. 18 N., R. 38 E., W.M.
RANGE IN CHARACTERISTICS: Mean annual soil temperature at a depth of 20 inches ranges from 47 degrees to 51 degrees F. Depth to bedrock is greater than 60 inches. The mollic epipedon is 10 to 20 inches thick. The the 0 to 40 inch particle-size control section has an estimated moist bulk density of 0.75 to 0.95 g/cc, volcanic glass content of more than 60 percent, acid-oxalate extractable aluminum plus one-half of the acid-oxalate extractable iron of 0.4 to 1.0 percent, and 15-bar water retention of 5 to 12 percent for air dried samples. Sodium saturation exceeds 15 percent in more than half of the upper 20 inches of the soil and decreases with depth below 20 inches.
The Akzn horizon has value of 4 or 5 dry, 2 or 3 moist, and chroma of 1 through 3 dry or moist. It is very strongly alkaline or strongly alkaline.
The Bkzn horizon has hue of 10YR or 2.5Y, value of 5 through 7 dry, 3 through 5 moist, and chroma of 1 through 4 dry or moist. It is ashy silt loam, ashy loam, or ashy very fine sandy loam. It is slightly effervescent to violently effervescent. Reaction is moderately alkaline to strongly alkaline.
Some pedons have a Bkg horizon.
The C horizon has value of 6 through 8 dry, 5 through 7 moist, and chroma of 2 or less. It is very strongly alkaline, strongly alkaline, or moderately alkaline in the upper part and mildly alkaline or moderately alkaline in the lower part. It is ashy silt loam, ashy loam, or ashy very fine sandy loam. It has 0 to 5 percent pebbles. The C horizon is absent in some pedons.
COMPETING SERIES: These are the Bossberg, Cocolalla, and Teeters series in other families. Bossberg and Cocolalla soils are noncalcareous throughout and have less than 15 percent sodium saturation. Teeters soils are medial, hard, and firm in the lower part of the control section and are mottled.
GEOGRAPHIC SETTING: Emdent soils are on bottomlands and basins at elevations of 900 to 2,600 feet. Slope is 0 to 5 percent. The soils formed in alluvium high in volcanic ash and have a seasonal high water table. The climate is continental with warm, dry summers and cool, moist winters with an average annual precipitation of 9 to 18 inches, an average January temperature of 29 degrees F, an average July temperature of 68 degrees F, and a mean annual temperature of 49 degrees F. The frost-free season ranges from 110 to 150 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Ahtanum, Anders, Bakeoven, Benge, Conconully, Duleylake, Nespelem, Poween (T), Timentwa, Stratford, and Walla Walla soils and the competing Bossberg soils. Ahtanum soils are 20 to 40 inches deep to a duripan. Anders soils have a lithic contact at a depth of 20 to 40 inches. Bakeoven soils have a lithic contact at a depth of less than 12 inches. Benge and Stratford soils are coarse-loamy over sandy or sandy-skeletal. Conconully, Poween, and Timentwa soils are coarse-loamy. Duleylake soils are fine-loamy. Nespelem and Walla Walla soils are coarse-silty.
DRAINAGE AND PERMEABILITY: Somewhat poorly and poorly drained; slow runoff; moderate permeability.
USE AND VEGETATION: Used for rangeland and wildlife habitat and used for cropland. Hay and pasture are common crops. Native vegetation is basin wildrye, alkali cordgrass, inland saltgrass, Baltic rush, alkali bluegrass, clustered field sedge, and woods rose..
DISTRIBUTION AND EXTENT: Eastern and northcentral Washington. The series is of moderate extent.
MLRA OFFICE RESPONSIBLE: Portland, Oregon
SERIES ESTABLISHED: Adams County, Washington, 1965.
REMARKS: Diagnostic horizons and features recognized in this pedon are a mollic epipedon from the surface to 16 inches, exchangeable sodium percentage of more than 15 percent in the upper 20 inches of the soil that becomes less with increasing depth, and more than 60 percent volcanic ash in the mollic epipedon and the particle-size control section. The description reflects a change in classification from to ashy, mesic Typic Vitraquands. to ashy, glassy, calcareous, mesic Typic Vitraquands.