LOCATION WETHEY WA

Established Series
Rev. NCD/SHB/EMM
03/2012

WETHEY SERIES

The Wethey series consists of deep, somewhat poorly drained soil formed in alluvium on floodplains, alluvial fans and depressional areas. Slopes are 0 to 3 percent. The average annual precipitation is about 19 inches and the mean annual temperature is about 46 degrees F.

TAXONOMIC CLASS: Sandy, mixed, mesic Aquic Xerofluvents

TYPICAL PEDON: Wethey loamy sand, grassland. (Colors are for dry soil unless otherwise stated.)

A1--0 to 13 inches; grayish brown (10YR 5/2) loamy sand, very dark grayish brown (10YR 3/2) moist; few fine distinct redox concentrations, dark yellowish brown (10YR 3/4) moist; weak fine and medium granular structure; soft, friable, nonsticky and nonplastic; common fine roots; few fine pores; slightly acid (pH6.5); clear wavy boundary.

A2--13 to 28 inches; grayish brown (10YR 5/2) loamy sand, very dark grayish brown (10YR 3/2) moist; few fine faint redox concentrations, dark brown (10YR 3/3) moist; massive; soft, friable, nonsticky and nonplastic; common fine roots; few fine pores; neutral (pH 6.8); clear wavy boundary. (combined thickness of A horizons 20 to 40 inches)

C1--28 to 40 inches; brown (10YR 5/3) loamy fine sand, dark brown (10YR 3/3) moist; common fine and medium distinct redox depletions, grayish brown (10YR 5/2) moist; massive; soft, friable, nonsticky and nonplastic; few fine roots; few fine pores; slightly acid (pH 6.5); clear wavy boundary.

C2--40 to 60 inches; light yellowish brown (10YR 6/4) loamy fine sand, dark yellowish brown (10YR 4/4) moist; common fine and medium distinct redox depletions, grayish brown (10YR 5/2) moist; massive; soft, friable, nonsticky and nonplastic; few fine roots; few fine pores; neutral (pH 6.8). (combined thickness of C horizons 10 to 35 inches thick)

TYPE LOCATION: Stevens County, Washington; about 400 feet south and 4100 feet west of the northeast corner of section 4, T. 37 N., R. 37 E.; USGS Marcus WA., topographic quadrangle. Latitude - 48 degrees, 44 minutes, 20 seconds North; Longitude - 118 degrees, 7 minutes, 25 seconds West; NAD 83.

RANGE IN CHARACTERISTICS: The soil is usually moist in all horizons but is dry in all parts between 12 and 35 inches for 45 to 60 consecutive days following the summer solstice in most years. The mean annual soil temperature at 20 inches ranges from 47 to 51 degrees F. The soil is slightly acid or neutral.

The A horizons have value of 4 to 7 dry, 2 to 7 moist, and chroma of 1 to 4. In some pedons, the surface 10 inches has average value of 6 or 7 dry and 4 to 7 moist. These horizons have weak granular or subangular blocky structure or it is single grained.

The C horizons have value of 5 or 6 dry, 3 or 4 moist, and chroma of 2 to 4. It is mostly loamy sand, and loamy fine sand, and has strata of sandy loam, or fine sandy loam. It has subangular blocky structure or it is massive. This horizon has few fine to many or very fine redox concentrations or depletions with hue of 10YR or 7.5YR, value of 3 to 5 moist, and chroma of 2 to 4 moist.

2Cg horizon (present in some pedons) - is stratified heavy silt loam to sand and is at depths of 40 inches or more. It has few medium to common
fine or medium redox features.

COMPETING SERIES: These are no competing series.

GEOGRAPHIC SETTING: Wethey soils are on floodplains, depressional areas, and alluvial fans at elevations of 1,500 to 2,300 feet. Slopes are smooth or undulating and are 0 to 3 percent. The soils formed in mixed sandy and loamy alluvium. Wethey soils are in continental climate having warm, dry summers and cool, moist winters. The mean annual temperature is about 46 degrees F. The average annual precipitation ranges from 16 to 22 inches. The frost free season ranges from 100 to 120 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Bisbee, Colville and Springdale soils. Bisbee and Springdale soils are on higher outwash terraces and do not have redox features within 60 inches. Colville soils are on similar lanforms have a mollic epipedon, are fine-silty and have calcium carbonate throughout.

DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY: Somewhat poorly drained; slow to very slow runoff; moderately high saturated hydraulic conductivity. These soils are subject to occasional flooding.

USE AND VEGETATION: Wethey soils are used for pasture, woodland, wildlife habitat, and some areas are cultivated. Small grains, alfalfa, and grasses are the principal crops. Native vegetation includes Douglas fir, ponderosa pine, and quaking aspen, with an understory of tufted hairgrass, common snowberry, wild rose, willow, red top and other grasses.

DISTRIBUTION AND EXTENT: Northeastern Washington MLRA 43A, 44A. Series is of small extent.

MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Bozeman, Montana

SERIES ESTABLISHED: Spokane County, Washington, 1961.

REMARKS: Diagnostic horizons and features recognized in this pedon are an ochric epipedon (assumed organic carbon content not met for this pedon) from the surface to 28 inches and a particle-size control section from 10 to 40 inches that is assumed to have an irregular decrease in organic carbon based on texture and soil color.

The Wethey series and the type location are no longer recognized in Spokane County as investigated during the Spokane County update (extensive revision) mainly due to variability in the alluvium and an assumed frigid soil temperature regime. For these reasons, the type location was moved to Stevens County in 03/2012. The majority of the Wethey soils mapped in the Spokane update (extensive revision) were correlated to higher taxa components with a frigid soil temperature regime.

MLRA 43A, 44A update notes - further investigation is needed to determine the soil temperature regime (mesic vs frigid) given the geographic extent and vegetation listed on the OSD of Wethey map units in Stevens County.

National Cooperative Soil Survey
U.S.A.