LOCATION WOLOT OREstablished Series
TAXONOMIC CLASS: Ashy over loamy, glassy over isotic, mesic Alfic Vitrixerands
TYPICAL PEDON: Wolot ashy silt loam, wooded. (Colors are for moist soil unless otherwise noted.)
Oi--0 to 1 inch; duff, needles, twigs.
A--1 to 5 inches; dark brown (10YR 3/3) ashy silt loam, light brownish gray (10YR 6/2) dry; weak fine granular structure; soft, very friable, nonsticky and nonplastic, moderately smeary; many very fine roots; many very fine irregular pores; neutral (pH 6.8); clear smooth boundary. (2 to 12 inches thick)
Bw--5 to 11 inches; brown (10YR 4/3) ashy silt loam, pale brown (10YR 6/3) dry; weak fine subangular blocky structure; soft, very friable, nonsticky and nonplastic, moderately smeary; common very fine and few medium roots; many very fine irregular pores; neutral (pH 6.8); clear smooth boundary. (5 to 12 inches thick)
BC--11 to 23 inches; dark yellowish brown (10YR 4/4) ashy silt loam, light yellowish brown (10YR 6/4) dry; weak medium subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic, moderately smeary; common very fine and few medium and coarse roots; many very fine irregular pores; neutral (pH 6.6); clear smooth boundary. (0 to 15 inches thick)
C--23 to 30 inches; brown (10YR 4/3) ashy silt loam, light yellowish brown (10YR 6/4) dry; massive; soft, very friable, nonsticky and nonplastic, moderately smeary; common very fine and few medium and coarse roots; few very fine irregular pores; neutral (pH 6.6); clear smooth boundary. (0 to 8 inches thick)
2Ab--30 to 37 inches; very dark grayish brown (10YR 3/2) silt loam, yellowish brown (10YR 5/4) dry; weak medium subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; common very fine and few medium and coarse roots; many very fine irregular pores; neutral (pH 7.0); clear smooth boundary. (0 to 9 inches thick)
2Bwb--37 to 43 inches; dark yellowish brown (10YR 3/4) silty clay loam, pale brown (10YR 6/3) dry; weak medium subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; common very fine and few medium coarse roots; many very fine irregular pores; neutral (pH 7.0); clear smooth boundary. (4 to 27 inches thick)
2Btb--43 to 61 inches; brown (10YR 4/3) silty clay loam, pale brown (10YR 6/3) dry; moderate medium subangular blocky structure; hard, firm, moderately sticky and moderately plastic; few fine and medium roots; many very fine irregular pores; common distinct clay films on faces of peds; common gray silt coatings on faces of peds; neutral (pH 7.0).
TYPE LOCATION: Union County, Oregon; 3 miles west of the town of Elgin; SW corner NE1/4 SW1/4 section 18, T. 1 N., R. 39 E.
RANGE IN CHARACTERISTICS: These soils have a bulk density of 0.65 to 0.85g per cubic centimeter in the ashy overlay with estimated phosphate retention of more than 25 percent, acid oxalate extractable aluminum plus one-half iron of more than 0.4 percent, and 15-bar moisture of less than 12 percent based on air-dried sample. The mean annual soil temperature ranges from 47 to 50 degrees F. The soils are usually moist but are dry between depths of 4 and 12 inches for 60 to 80 consecutive days following the summer solstice. Thickness of the ashy materials and depth to the buried soil is 20 to 40 inches. The buried argillic horizon (2Btb) is within a depth of 50 inches. The thickness of the solum within the volcanic ash mantle is 10 to 22 inches. Depth to bedrock is greater than 60 inches.
The A horizon has hue of 10YR or 7.5YR, value of 2 or 3 moist, 4 through 6 dry, and chroma of 1 through 3 moist and dry. Texture is silt loam with 5 to 15 percent clay.
The Bw horizon has hue of 10YR or 7.5YR, value of 3 through 5 moist, 6 or 7 dry, and chroma of 2 through 4 moist and dry. Texture is silt loam with 5 to 15 percent clay.
The C horizon has value of 3 through 5 moist, 5 or 6 dry, chroma of 3 or 4 moist and dry.
The 2Bwb and 2Btb horizons have value of 3 or 4 moist, 5 or 6 dry, and chroma of 2 through 4 moist and dry. Texture is silt loam or silty clay loam with 18 to 35 percent clay. Rock fragments range from 0 to 10 percent gravel in the 2Btb horizon.
COMPETING SERIES: There are no competing series.
Series with a similar Typic subgroup classification and amorphic mineralogy include the Chuckanut and Reinecke series.
Chuckanut soils - paralithic contact at depths of 40 to 60 inches; a Bs horizon; lack a 2Bwb horizon
Reinecke soils - upper pscs with sandy loam texture and a clay estimate of 3 to 5 percent; the lower pscs has hue of 7.5YR through 2.5YR
Series with a similar Typic subgroup classification and glassy mineralogy include the Collegecreek and Cupper (T) soils.
Collegecreek soils - lower pscs has 10 to 18 percent clay
Cupper soils - lower pscs has secondary lime (Bkb horizons)
GEOGRAPHIC SETTING: Wolot soils are on foot slopes, toeslopes and fans of hills and mountains. Elevations are 1,900 to 3,900 feet. Slope is 0 to 30 percent. These soils formed in silty volcanic ash deposited over older loess and colluvium. The climate is characterized by cool wet winters and hot dry summers. The mean annual precipitation is 15 to 25 inches The mean annual temperature is 45 to 48 degrees F. The frost-free period is 100 to 150 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Gwinly, Klicker, Lookingglass, and Rockly soils. Gwinly, Klicker and Rockly soils are skeletal and are less than 60 inches deep to bedrock. Lookingglass soils have a clayey B horizon.
DRAINAGE AND PERMEABILITY: Well-drained; moderately slow permeability.
USE AND VEGETATION: These soils are used for timber production. Some areas have been cleared and are used for wheat and grass seed production. Other uses are wildlife habitat and water supply. Native vegetation is ponderosa pine, Douglas-fir, western larch, snowberry, spirea, arnica, elk sedge, pinegrass and Idaho fescue.
DISTRIBUTION AND EXTENT: Northeastern Oregon; MLRA 43c. The series is of small extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Portland, Oregon
SERIES ESTABLISHED: Union County, Oregon, 1978.
REMARKS: Diagnostic horizons and features:
Ochric epipedon - from 0 to 4 inches (A horizon)
Cambic horizon - 4 to 10 inches
Andic properties - from 0 to 29 inches
Particle-size control section - from 0 to 40 inches with 0 to 29 inches meeting ashy family (A, Bw, BC, and C horizons) and 29 to 40 inches meeting loamy family (2Ab and upper 4 inches of 2Bwb horizon)
Alfic feature - argillic horizon beginning at 43 inches and within 50 inches of the mineral soil surface
Reclassification 08/2001 from ashy over loamy, mixed, mesic Typic Vitrandepts based on Keys to Taxonomy, 8th edition.
Reclassification 06/2006 from Typic Vitrixerands to Alfic Vitrixerands based on Keys to Taxonomy, 9th edition.
ADDITIONAL DATA: The data for ashy family placement is extrapolated from reference samples on Tolo, Crackler and Rouen series.