LOCATION GIDWIN WAEstablished Series
TAXONOMIC CLASS: Loamy-skeletal, mixed, superactive, frigid Lithic Argixerolls
TYPICAL PEDON: Gidwin cobbly silt loam- rangeland, on a 46 percent northeast-facing slope at 3,700 feet elevation. (Colors are for dry soils unless otherwise stated. All textures are apparent field textures.)
A--0 to 3 inches; dark grayish brown (10YR 4/2) cobbly silt loam, very dark brown (10YR 2/2) moist; weak fine and medium granular structure; soft, very friable, nonsticky and nonplastic; many very fine roots; common very fine irregular pores; 15 percent gravel, 15 percent cobbles; neutral (pH 6.8); clear wavy boundary. (2 to 4 inches thick)
AB--3 to 7 inches; brown (10YR 5/3) very gravelly loam, dark brown (10YR 3/3) moist; weak fine subangular blocky structure; soft, friable, slightly sticky and slightly plastic; many very fine, few medium and fine roots; common very fine irregular pores; 35 percent gravel, 10 percent cobbles; neutral (pH 7.0); clear wavy boundary.(2 to 7 inches thick)
Bt1--7 to 12 inches; brown (10YR 5/3) extremely gravelly loam, dark brown (10YR 3/3) moist; moderate medium and fine subangular blocky structure; soft, friable, slightly sticky and slightly plastic; many very fine, few fine and few medium roots; few very fine tubular pores; common distinct clay films on the faces of peds; 60 percent gravel, 10 percent cobbles; neutral (pH 7.0); clear wavy boundary.
Bt2--12 to 17 inches; brown (10YR 5/3) extremely gravelly loam, dark brown (10YR 3/3) moist; weak medium subangular blocky structure; soft, friable, slightly sticky and slightly plastic; common very fine roots; common very fine tubular pores; few faint clay films lining pores and on faces of peds; 65 percent gravel, 5 percent cobbles; neutral (pH 7.2); abrupt irregular boundary. (Combined thickness for the Bt horizon is 3 to 24 inches)
R--17 inches; basalt.
TYPE LOCATION: Yakima County, Washington, about 1,900 feet west and 1,100 feet north of the southeast corner of section 30, T. 14 N., R. 22 E.; USGS Black Rock Spring NE topographic quadrangle; Latitude 46 degrees, 40 minutes, 05 seconds N. and Longitude 120 degrees, 06 minutes, 48 seconds W.
RANGE IN CHARACTERISTICS: The mean annual soil temperature is 44 to 47 degrees F. These soils are usually moist, but are dry in the moisture control section for 75 to 90 consecutive days following the summer solstice. The particle-size control section has 18 to 27 percent clay in the fine earth fraction and 45 to 85 percent rock fragments by volume. Organic matter is estimated to range from 1 to 4 percent. Solum thickness and depth to bedrock ranges from 14 to 20 inches. The mollic epipedon is 14 to 20 inches thick and includes all of the argillic horizon. Reaction is slightly acid or neutral.
The A horizon is cobbly silt loam, gravelly silt loam or gravelly loam.
The AB horizon has value of 4 or 5 dry, 2 or 3 moist, and a chroma of 2 or 3, dry or moist. It is very gravelly loam, very cobbly loam, gravelly loam, or very gravelly silt loam.
The Bt horizon has value of 4 or 5 dry, 2 or 3 moist and chroma of 2 to 4 dry, 2 or 3 moist. It is very gravelly clay loam, very gravelly loam, extremely gravelly loam, very cobbly loam, or extremely cobbly loam. It has 35 to 85 percent rock fragments.
COMPETING SERIES: These are the Anaud (T), Bellenmine (T), Cleavage, Cleavmor, Cropper, Gabica, Gaciba, Grosschat (T), Hutchley, Mascamp, Melling, Pernog, Pernty, Poisoncreek (T), Rozara, Shalcleav, Shalper, Slatter (T), Tractuff and Tweener. Anaud soils are dry for more than 90 consecutive days after the summer solstice. Bellenmine and Cleavage soils have a mollic epipedon 7 to 10 inches thick. Cleavmor soils are usually dry and have lime in seams or filaments in the Btk horizons. Cropper soils have a mollic epipedon 7 to 10 inches thick and 25 to 35 percent clay in the control section. Gabica soils have moderately slow permeability and are dry for 45 to 70 consecutive days following the summer solstice. Gaciba soils are mollic only in part of the argillic horizon and have an aridic soil moisture regime. Grosschat soils receive 10 to 20 days of summer precipitation between July and October and a mollic epipedon 7 to 12 inches thick. Hutchley soils have 24 to 35 percent clay in the particle-size control section. Mascamp soils are usually dry and have lime coatings on the bedrock surface. Melling soil shave 27 to 35 percent clay in the particle-size control section and are dry for 45 to 60 consecutive days. Pernog soils are dry for 45 to 70 consecutive days following the summer solstice and have 25 to 35 percent clay in the particle-size control section. Pernty soils have mollic epipedons 7 to 10 inches thick which includes only the upper Bt horizon and are dry for 90 to 120 consecutive days following the summer solstice. Poisoncreek soils have a Cr horizon above the bedrock. Rozara soils contain 14 to 18 percent clay in the control section and have a lithic contact at 10 to 14 inches. Shalcleav soils have 28 to 35 percent clay in the particle-size control section and have mainly channers and flagstones in the profile. Slatter soils have a lithic contact at 4 to 10 inches. Shalper soils have mollic epipedons that are 4 to 12 inches thick and have moderately slow permeability. Tractuff soils have Btk horizons with secondary carbonates and an aridic soil moisture regime. Tweener soils have 25 to 40 percent clay in the particle-size control section and moderately slow permeability.
GEOGRAPHIC SETTING: Gidwin soils are on hillslopes and have slopes of 0 to 70 percent slopes. These soils formed in colluvium and residuum from basalt and loess. Elevation is 3,100 to 5,400 feet. These soils are in a semiarid climate with warm dry summers and cold moist winters. The mean annual precipitation is 12 to 20 inches. The average January temperature is about 24 degrees F. and the average July temperature is about 68 degrees F. The mean annual temperature is 42 to 45 degrees F. The frost-free season is 70 to 110 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Frint and Hogranch soils on hillslopes. Frint soils are 20 to 40 inches to bedrock. Hogranch soils are more than 40 inches to bedrock.
DRAINAGE AND PERMEABILITY: Well drained; moderate permeability.
USE AND VEGETATION: These soils are used for livestock grazing and wildlife habitat. Native vegetation is Idaho fescue, bluebunch wheatgrass, Sandberg bluegrass, and threetip sagebrush.
DISTRIBUTION AND EXTENT: Yakima and Kittitas Counties, Washington. Series is of small extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Portland, Oregon
SERIES ESTABLISHED: Kittitas County, Washington, Yakima Training Center, 1994.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
Mollic epipedon the zone from 0 to 17 inches
Argillic horizon the zone from 7 to 17 inches
Lithic contact the zone beginning at 17 inches
Particle-size control section - the zone from 7 to 17 inches (argillic horizon).