LOCATION ALMOTA WA+ID OREstablished Series
TAXONOMIC CLASS: Fine-loamy, mixed, superactive, mesic Calcic Haploxerolls
TYPICAL PEDON: Almota silt loam, cultivated. (Colors are for dry soil unless otherwise stated.)
Ap1--0 to 3 inches; dark grayish brown (10YR 4/2) silt loam, very dark brown (10YR 2/2) moist; weak fine and medium granular structure; slightly hard, very friable, slightly sticky and slightly plastic; many fine and few medium roots; many fine and very fine pores; neutral (pH 7.2); abrupt smooth boundary. (2 to 3 inches thick)
Ap2--3 to 9 inches, dark grayish brown (10YR 4/2) silt loam, very dark brown (10YR 2/2) moist; weak very fine subangular blocky structure; slightly hard, very friable, slightly sticky, and slightly plastic; many fine and few medium roots; many fine and very fine pores; neutral (pH 7.2); abrupt smooth boundary. (4 to 6 inches thick).
AB--9 to 11 inches; grayish brown (10YR 5/2) silt loam, very dark grayish brown (10YR 3/2) moist; weak medium prismatic structure that parts to weak fine and medium platy structure; slightly hard, very friable, slightly sticky and slightly plastic; many fine roots; common fine and medium pores; 3 percent basalt fragments; slightly alkaline (pH 7.8); clear wavy boundary. (2 to 4 inches thick)
BA--11 to 19 inches; brown (10YR 5/3) silt loam, dark brown (10YR 3/3) moist; moderate medium prismatic structure; slightly hard, very friable, slightly sticky and slightly plastic; many fine roots; common fine and medium pores; 3 percent basalt fragments; slightly alkaline (pH 7.8); clear wavy boundary. (4 to 9 inches thick)
Bw--19 to 29 inches; pale brown (10YR 6/3) silt loam, brown (10YR 4/3) moist; moderate coarse and medium prismatic structure; slightly hard, friable, slightly sticky and slightly plastic; common fine roots; common fine and medium pores; 14 percent basalt fragments; moderately alkaline (pH 8.0); clear irregular boundary. (5 to 13 inches thick)
Bk--29 to 35 inches; white (10YR 8/2) very gravelly silt loam, light brownish gray (10YR 6/2) moist; massive; hard, firm, slightly sticky and slightly plastic; few medium and fine roots; common fine and medium pores partially filled with lime; 40 percent basalt fragments; effervescent; moderately alkaline (pH 8.4); abrupt irregular boundary. (3 to 19 inches thick)
2R--35 inches, fractured basalt with lime in some of the fractures.
TYPE LOCATION: Whitman County, Washington; 2,300 feet north and 200 feet east of the SW corner of sec. 26, T.16N., R.41E.
RANGE IN CHARACTERISTICS: Basalt bedrock is at a depth of 20 to 40 inches. Mean annual soil temperature is about 52 degrees F. The soils are usually moist, but are dry in all parts between depths of 8 and 24 inches for 60 to 90 consecutive days. The particle size control section is silt loam with 18 to 25 percent clay and has a weighted average of 1 to 20 percent basalt rock fragments. The mollic epipedon is 12 to 20 inches thick.
The A and AB horizons have value of 4 or 5 dry, and 2 or 3 moist, chroma of 1 to 3 dry or moist. It has weak or moderate granular, blocky or platy structure. This horizon is neutral or slightly alkaline.
The Bw and BA horizons have value of 4 to 6 dry, 3 or 4 moist and chroma of 2 to 4 moist or dry. It is silt loam or loam with weak or moderate blocky or prismatic structure. This horizon is neutral to moderately alkaline.
The Bk horizon has value of 6 through 8 dry, 4 through 7 moist and chroma of 1, 2, or 3 dry or moist. It is silt loam or loam. It is moderately to very strongly alkaline.
COMPETING SERIES: These are the Bickleton, Highland, Lebec, and Nims series. Highland soils are more than 40 inches deep to bedrock. Lebec soils are calcareous throughout and have limestone bedrock at a depth of 30 to 40 inches. Nims soils have 20 to 50 percent indurated durinodes in the lower part of the particle-size control section.
GEOGRAPHIC SETTING: Almota soils are on sloping to very steep uplands at elevations of 1,500 to 2,700 feet. These soils formed in loess and colluvium from basalt. Summers are warm and dry, winters are cold and moist. Mean annual precipitation is 12 to 18 inches. Average January temperature is 28 degrees F., mean July temperature is 68 degrees F., average annual temperature is 49 degrees to 51 degrees F., with a frost-free season of 130 to 160 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Athena, Calouse, Kuhl, Spofford, and Tucannon soils. Athena and Calouse soils are deeper than 40 inches to bedrock. Kuhl soils have bedrock at depths of 10 to 20 inches. Spofford soils have natric horizons. Tucannon soils have a mollic epipedon more than 20 inches thick.
DRAINAGE AND PERMEABILITY: Well drained; slow to rapid runoff; moderate permeability.
USE AND VEGETATION: Used for production of winter wheat and for grazing land. Native vegetation is mainly bluebunch wheatgrass, Idaho fescue, Sandberg bluegrass, big bluegrass, arrowleaf balsamroot, wild buckwheat, western yarrow, and sagebrush.
DISTRIBUTION AND EXTENT: Southeastern Washington, northcentral Idaho and possibly eastern Oregon. The soils are moderately extensive.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Portland, Oregon
SERIES ESTABLISHED: Whitman County, Washington, 1975.
REMARKS: Diagnostic horizons and features recognized in this pedon are a mollic epipedon from the surface to 19 inches, a cambic horizon from 19 to 29 inches, a zone of carbonate accumulation from 29 to 35 inches, and a lithic contact at 35 inches.