LOCATION GORST WAEstablished Series
TAXONOMIC CLASS: Loamy, mixed, superactive, mesic, shallow Haploduridic Durixerolls
TYPICAL PEDON: Gorst loam - abandoned field. (Colors are for dry soil unless otherwise stated.)
Ap--0 to 7 inches; brown (10YR 5/3) loam, dark brown (10YR 3/3) moist; weak subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; many roots; few fine tubular pores; slightly alkaline (pH 7.4); abrupt wavy boundary. (6 to 9 inches thick)
Bw1--7 to 10 inches; pale brown (10YR 6/3) loam, brown (10YR 4/3) moist; moderate medium prismatic structure; hard, firm, slightly sticky and plastic; few roots; common fine tubular pores; 1 percent gravel and 1 percent cobbles; slightly alkaline (pH 7.4); clear wavy boundary. (2 to 4 inches thick)
Bw2--10 to 15 inches; brown (7.5YR 5/4) loam, dark brown (7.5YR 3/4) moist; moderate medium angular blocky structure parting to moderate fine blocky; hard, firm, slightly sticky and plastic; few roots; many very fine tubular pores; 1 percent gravel and 4 percent cobbles; slightly alkaline (pH 7.6); abrupt smooth boundary. (4 to 7 inches thick)
2Bkqm--15 inches; silica indurated gravelly duripan.
TYPE LOCATION: Yakima County, Washington; 1,140 feet west and 400 feet south of the northeast corner of section 33, T. 13 N., R. 17 E., W.M.
RANGE IN CHARACTERISTICS: Depth to the duripan ranges from 12 to 20 inches. The mean annual soil temperature ranges from 48 degrees to 54 degrees F. These soils are dry in all parts between depths of 4 and 12 inches more than half of the time when the soil temperature is above 40 degrees F. The mollic epipedon ranges from 7 to 9 inches thick. The particle-size control section averages 18 to 25 percent clay and more than 15 percent fine sand or coarser including rock fragments.
The A horizon has value of 4 or 5 dry, 2 or 3 moist, and chroma of 2 or 3 moist or dry. It has weak or moderate structure. It is neutral or slightly alkaline.
The Bw horizon has hue of 10YR or 7.5YR, value of 5 or 6 dry, 3 or 4 moist, and chroma of 3 or 4 moist or dry. It is loam or silt loam and can be gravelly. It has moderate prismatic or blocky structure. It has 0 to 20 percent rock fragments.
The 2Bkqm horizon is indurated, has a gravelly to extremely gravelly matrix 4 to 36 inches thick with 1 to 5 inch thick plates. It overlies weakly cemented to indurated alluvial material.
COMPETING SERIES: These are the Blalock, Chainlink (T), Moxee, Urmafot and Vadaho series. Blalock soils have a very strongly calcareous duripan. Chainlink and Moxee soils have less than 18 percent clay and more than 10 percent coarse fragments. Urmafot and Vadaho soils have a calcic horizon within the particle-size control section. Vadaho soils lack a cambic horizon.
GEOGRAPHIC SETTING: Gorst soils are on uplands and high dissected terraces and alluvial fans at elevations of 1,200 to 2,900 feet. Slopes are 0 to 30 percent. These soils formed in a thin loess mantle over a duripan. The gravel of the 2Bkq horizon is associated with the Ellensburg formation. The soils are in a semiarid climate with hot, dry summers and cool, moist winters. The mean annual precipitation ranges from 8 to 12 inches. Mean annual temperature is 49 degrees to 54 degrees F., and the frost-free season is 135 to 170 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Cowiche, Harwood, and Selah soils. Cowiche soils are on upland and are more than 40 inches deep. Harwood soils on uplands and terraces and Selah soils on alluvial fans are 20 to 40 inches deep to a duripan.
DRAINAGE AND PERMEABILITY: Well drained; slow to medium runoff; moderate permeability above the duripan and very slow within the duripan.
USE AND VEGETATION: Pasture and some orchards. Native vegetation is bunchgrass and big sagebrush.
DISTRIBUTION AND EXTENT: South-central Washington. Series is of moderate extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Portland, Oregon
SERIES ESTABLISHED: Yakima County, Washington, 1979.