LOCATION WAMIC              OR
Established Series
Rev. GLG/AON/RWL
12/1999

WAMIC SERIES


The Wamic series consists of deep, well-drained soils that formed in mixed loess and ash over alluvium and colluvium weathered from basalt or andesite. These soils are on uplands. Slopes are to 70 percent. The mean annual precipitation is about 18 inches and the mean annual temperature is about 48 degrees F.

TAXONOMIC CLASS: Fine-loamy, mixed, superactive, mesic Vitrandic Haploxerepts

TYPICAL PEDON: Wamic loam, cultivated. (Colors are for moist soil unless otherwise noted.)

Ap--0 to 7 inches; very dark grayish brown (10YR 3/2) loam, light brownish gray (10YR 6/2) dry; weak fine granular structure; slightly hard, friable, slightly sticky and slightly plastic; many very fine roots; many very fine irregular pores; neutral (pH 6.6); abrupt smooth boundary. (6 to 10 inches thick)

Bw1--7 to 18 inches; dark brown (10YR 3/3) loam, light brownish gray (10YR 6/2) dry; weak medium subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; many very fine roots; many very fine tubular pores; neutral (pH 6.7); clear wavy boundary. (0 to 13 inches thick)

Bw2--18 to 28 inches; brown (10YR 4/3) loam, light brownish gray (10YR 6/2) dry; weak medium subangular blocky structure; hard, friable, slightly sticky and slightly plastic; common very fine roots; many very fine and common fine tubular pores; about 2 percent very fine gravel; light gray (10YR 7/2) with dry coatings of very fine sand on faces of peds; neutral (pH 6.8); abrupt wavy boundary. (8 to 15 inches thick)

2C--28 to 44 inches; brown (10YR 4/3) heavy loam, pale brown (10YR 6/3) dry; massive; very hard, very firm, sticky and plastic; few fine roots; many very fine and common fine tubular pores; about 2 percent very fine gravel; brown (7.5YR 4/4) when dry thick clay films in nearly all pores and on faces of fractures; neutral (pH 6.8).

2R--44 inches; bedrock

TYPE LOCATION: Wasco County, Oregon; 100 feet south of road in the northeast 1/4 northwest 1/4 northwest 1/4, sec. 26, T. 2 S., R. 12 E.

RANGE IN CHARACTERISTICS: The soils are usually moist but are dry for 60 to 80 consecutive days in more than 7 out of 10 years throughout the moisture control section. The mean annual soil temperature ranges from 47 to 52 degrees F. The thickness of the solum and depth to the 2C horizon ranges from 24 to 36 inches and depth to bedrock is 40 to 60 inches. The control section has 18 to 27 percent clay and more than 18 percent coarser than very fine sand. The solum has hue of 10YR or 7.5YR. The solum is estimated to have a volcanic glass content of 5 to 20 percent and acid oxalate extractable aluminum plus one-half iron of 0.4 to 1.0 percent.

The A horizon has value of 5 or 6 dry, 3 or 4 moist and chroma of 2 or 3 moist and dry. It is very fine sandy loam, loam, or silt loam. This horizon has weak granular or subangular blocky structure.

The Bw horizon has value of 5 or 6 dry and chroma of 2 to 4 moist and dry. It is loam or silt loam.

The C1 horizon, where present, is massive and has few to common very firm noncalcareous nodules 1/2 to 3/4 inch in diameter and is similar to the B horizon in texture. The 2C horizon is heavy loam, clay loam, or sandy clay loam with 20 to 30 percent clay. It is very hard or extremely hard and firm or very firm. This horizon has brown or reddish brown, moderately thick or thick clay films mostly in pores and fractures but distributed throughout the mass in some pedons.

COMPETING SERIES: There are no competing series.

GEOGRAPHIC SETTING: The Wamic soils are on uplands and have nearly level to very steep slopes with gradients generally ranging from 0 to 20 percent but ranging to 70 percent in some areas and are at elevations of 1,000 to 3,600 feet. The soils formed in mixed volcanic ash and loess over medium or moderately fine textured alluvium or colluvium weathered from basalt or andesite. The climate is characterized by cool wet winters and hot dry summers. The mean July temperature is 63 degrees F.; the mean January temperature is 37 degrees F. The mean annual temperature is 45 to 50 degrees F. The mean annual precipitation is 14 to 25 inches.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Bald, Bodell, Frailey, Hesslan, and Skyline soils. These soils are dominantly on steeper slopes with south aspects. Bald soils are loamy-skeletal and are 20 to 40 inches deep to a lithic contact. Bodell soils are grassland soils, have mollic epipedons and are less than 20 inches deep to a lithic contact. Frailey soils are coarse-loamy, have more than 15 percent rock fragments in the control section and lack firm or very hard 2C horizons above depth of 40 inches. Hesslan soils have mollic epipedons, are commonly stony, and are 20 to 40 inches deep to a paralithic contact. Skyline soils have mollic epipedons and are less than 20 inches to a paralithic contact.

DRAINAGE AND PERMEABILITY: Well-drained; moderately slow permeability.

USE AND VEGETATION: Principal use is for grain production. Other uses are hay and pasture, livestock grazing, woodland and recreation. Vegetation is mainly an overstory of white oak and ponderosa pine. Shrubs are bitterbrush, deerbrush, and snowberry. Idaho fescue is the predominant grass with bluebunch wheatgrass, prairie junegrass and Sandberg bluegrass.

DISTRIBUTION AND EXTENT: North-central Oregon; MLRA 6. The series is moderately extensive.

MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Portland, Oregon

SERIES ESTABLISHED: Wasco County, Oregon, 1975.

REMARKS: This draft reflects a change in classification from fine-loamy, mixed, mesic Typic Xerochrepts based on the Andisol Order.

Diagnostic horizons and features recognized in this pedon:

Ochric epipedon - from 0 to 7 inches (Ap horizon)

Cambic horizon - from 7 to 28 inches (Bw1 and Bw2 horizons)

Particle-size control section - from 10 to 40 inches.

ADDITIONAL DATA: Characterization data on 2 profiles (S57-Oreg-33-8 and 33-9) reported in Riverside Soil Survey Laboratory Report for soils in Wasco, Sherman and Gilliam Counties, Oregon, May, 1959.


National Cooperative Soil Survey
U.S.A.