LOCATION SETNUM             WA
Established Series
Rev. MEH/KWH/RWL
11/2008

SETNUM SERIES


The Setnum series consists of moderately deep, somewhat poorly drained soils that formed in alluvium from loess and basalt. Setnum soils are in depressions on plateaus and along drainages. Slopes are 0 to 3 percent. The mean annual precipitation is about 17 inches and the mean annual temperature is about 47 degrees F.

TAXONOMIC CLASS: Fine, mixed, superactive, mesic Xeric Argialbolls

TYPICAL PEDON: Setnum silt loam- cropland, on a 2 percent slope at an elevation of 1,675 feet. (Colors are for dry soil unless otherwise noted. All textures are apparent field textures.)

Ap--0 to 10 inches; dark gray (10YR 4/1) silt loam, black (10YR 2/1) moist; moderate fine and medium subangular blocky structure slightly hard, very friable, slightly sticky and slightly plastic; few very fine roots; many fine irregular pores; slightly acid (pH 6.4); clear wavy boundary. (10 to 15 inches thick)

E--10 to 17 inches; light gray (10YR 7/1) silt loam, dark grayish brown (10YR 4/2) moist; moderate fine and medium subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; few very fine roots; common fine tubular pores; neutral (pH 6.6); abrupt smooth boundary. (2 to 8 inches thick)

Btss--17 to 26 inches; dark brown (10YR 3/3) clay, very dark grayish brown (10YR 3/2) moist; few fine distinct redox concentrations; moderate fine prismatic structure; very hard, firm, very sticky and very plastic; common very fine and fine roots; common fine tubular pores; few slickensides and many prominent clay films on faces of peds; neutral (pH 6.8); clear wavy boundary.

Bt--26 to 31 inches; dark yellowish brown (10YR 3/4) clay loam, dark brown (10YR 3/3) moist; strong medium angular blocky structure; hard, firm, moderately sticky and moderately plastic; common very fine and fine roots; common fine tubular pores; common faint clay films on faces of peds; neutral (pH 7.2); gradual wavy boundary. (Combined thickness of the Bt horizon is 6 to 18 inches thick)

BC--31 to 39 inches; yellowish brown (10YR 5/4) loam, dark yellowish brown (10YR 4/4) moist; weak fine angular blocky structure; hard, friable, slightly sticky and slightly plastic; few fine roots; common fine tubular pores; neutral (pH 7.2); abrupt wavy boundary. (2 to 9 inches thick)

R--39 inches; basalt.

TYPE LOCATION: Klickitat County, Washington; about 3 miles southwest of Goldendale; 300 feet north and 1,250 feet east of the southwest corner of section 36, T.4N., R.15E. (Latitude 45 degrees, 46 minutes, 57 seconds N. and Longitude 120 degrees, 52 minutes, 46 seconds W.)

RANGE IN CHARACTERISTICS: The mean annual soil temperature is 48 to 52 degrees F. The soil is dry in all parts of the moisture control section for 75 to 90 consecutive days following the summer solstice. Depth to bedrock ranges from 20 to 40 inches. Thickness of the mollic epipedon ranges from 10 to 15 inches. The particle-size control section has 35 to 45 clay in the fine-earth fraction and 0 to 5 percent gravel.
The Ap horizon has a value of 4 or 5 dry, 2 or 3 moist and a chroma of 1 or 2 dry and moist. Soil reaction is slightly acid or moderately acid.
The E horizon has a value of 6 or 7 dry, 4 or 5 moist and a chroma of 1 or 2 dry and moist. Texture is silt loam or loam. It has 18 to 25 percent clay and 0 to 5 percent gravel. Soil reaction is slightly acid or neutral.
The Btss or Bt horizon has hue of 2.5YR or 10YR, value of 3 to 6 dry, 3 or 4 moist and chroma of 2 to 4 dry or moist. Texture is clay or clay loam. It has 35 to 45 percent clay and 0 to 5 percent gravel. Soil reaction is slightly acid or neutral.
The BC horizon has hue of 2.5YR or 10YR, value of 5 to 7 dry, 3 to 6 moist and chroma of 3 to 5 dry or moist. Texture is clay loam or loam. It has 18 to 35 percent clay and 0 to 15 percent gravel. Soil reaction is slightly acid or neutral.

COMPETING SERIES: These are the Latah, Quicksell, and Tilma series.
Latah soils greater than 60 inches to bedrock; dry for 45 to 60 consecutive days following the summer solstice
Quicksell soils greater than 60 inches to bedrock; pscs has 45 to 55 percent clay
Tilma soils greater than 60 inches to bedrock; mollic epipedon 16 to 23 inches thick

GEOGRAPHIC SETTING: Setnum soils are in depressions on plateaus and along drainages at elevations of 1,400 to 3,600 feet. These soils formed in alluvium derived from basalt mixed with loess. Slopes are 0 to 3 percent. Summers are warm and dry and winters are cool and moist. The mean annual precipitation is 15 to 18 inches. The average January temperature is 27 degrees F. and the average July temperature is 65 degrees F. The mean annual temperature is 46 to 50 degrees F. The frost-free season is 110 to 150 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Blockhouse, Goldendale, Lorena, and Munset soils. Blockhouse soils are on broad alluvial plains and are moderately well drained. Goldendale and Lorena soils are on plateaus and are well drained. Munset soils are in depressions and are poorly drained.

DRAINAGE AND PERMEABILITY: Somewhat poorly drained; slow runoff; slow permeability. A perched water table is present from November to June with it's highest level occurring during late winter and early spring.

USE AND VEGETATION: These soils are used mainly for livestock grazing, crop production, and wildlife habitat. Native vegetation is mainly sandberg bluegrass, sixweeks fescue, sedge, biscuitroot, and camas.

DISTRIBUTION AND EXTENT: Klickitat County, Washington. MLRA 8. The series is of small extent.

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

SERIES ESTABLISHED: Klickitat County, Washington, 2003. Name is coined.

REMARKS: Diagnostic horizons and features recognized in this pedon are:
Mollic epipedon - the zone from 1 to 10 inches
Albic horizon - the zone from 10 to 17 inches
Argillic horizon - the zone from 17 to 31 inches
Lithic contact - the zone beginning at 39 inches
Particle-size control section - the zone from 17 to 31 inches (Btss and Bt horizons)
COLE - value for 0 to 39 inch depth is 5.8

ADDITIONAL DATA: This soil was previously called Munset Variant.


National Cooperative Soil Survey
U.S.A.