LOCATION UMAPINE WA+OREstablished Series
TAXONOMIC CLASS: Coarse-silty, mixed, superactive, calcareous, mesic Typic Halaquepts
TYPICAL PEDON: Umapine silt loam - grassland. (Colors are for dry soil unless otherwise stated)
Akn--0 to 9 inches; light brownish gray (10YR 6/2) silt loam, dark grayish brown (10YR 4/2) moist; weak thick platy structure; slightly hard, friable, slightly sticky and slightly plastic; many fine roots; vesicular pores; violently effervescent; very strongly alkaline (pH 9.2); abrupt smooth boundary. (5 to 12 inches thick)
Bknl--9 to 19 inches; grayish brown (10YR 5/2) silt loam, very dark grayish brown (10YR 3/2) moist; massive; slightly hard, friable, slightly sticky and slightly plastic; many fine roots; violently effervescent; very strongly alkaline (pH 9.6); gradual wavy boundary. (0 to 15 inches thick)
Bkn2--19 to 28 inches; gray (10YR 6/1) silt loam, dark grayish brown (10YR 4/2) moist; few faint redox concentrations; massive; slightly hard, friable, slightly sticky and slightly plastic; many fine roots; many very fine tubular pores; violently effervescent; strongly alkaline (pH 9.0); gradual wavy boundary. (6 to 15 inches thick)
Bkn3--28 to 41 inches; light gray (10YR 7/1) silt loam, gray (10YR 5/1) moist; few faint redox concentrations; massive; slightly hard, friable, slightly sticky and slightly plastic; few roots; many fine tubular pores; lime both disseminated and segregated in fine, soft masses and thread; violently effervescent; strongly alkaline (pH 8.8); clear wavy boundary.(10 to 16 inches thick)
C--41 to 60 inches; grayish brown (10YR 5/2) silt loam, dark grayish brown (10YR 4/2) moist; few faint redox concentrations; massive; slightly hard, friable, nonsticky and nonplastic; few roots; violently effervescent; strongly alkaline (pH 8.6).
TYPE LOCATION: Adams County, Washington; 600 feet north, 540 feet east of west quarter corner section 6, T. 15 N., R. 28 E., W.M.
RANGE IN CHARACTERISTICS: These soils are saturated within 40 inches of the surface at some time of the year in most years. The mean annual soil temperature is 48 to 55 degrees F. The upper 40 inches of soil is strongly alkaline or very strongly alkaline. The exchangeable sodium percentage exceeds 15 percent in the upper 20 inches and decreases with increasing depth.
The Akn horizon has hue of 10YR or 2.5Y, value of 3 to5 moist, 5 or 6 dry and chroma of 1 to 3 moist and dry.
The Bkn horizon has hue of 10YR or 2.5Y, value of 3 to 5 moist, 5 to 7 dry and chroma of 1 or 2 moist and dry. It has redox concentrations within a depth of 20 inches in some pedons. Texture is silt loam or very fine sandy loam. Reaction is strongly alkaline or very strongly alkaline.
The C horizon has hue of 10YR or 2.5Y, value of 3 or 4 moist and 5 or 6 dry. Reaction is slightly alkaline to very strongly alkaline.
COMPETING SERIES: These are the Janise, Sinloc, and Stanflow series. Janise soils have a thin E horizon and thin Bt horizon. Sinloc soils are stratified silt loam, very fine sandy loam and fine sandy loam in the lower part of the particle-size control section. Stanflow soils are moderately well drained and have a weakly cemented layer at a depth of 20 to 40 inches.
GEOGRAPHIC SETTING: Umapine soils are in basins and on low terraces at elevations of 250 to 3,500 feet. Slopes are 0 to 5 percent. These soils formed in alluvium from loess The mean annual precipitation is 6 to 12 inches. Umapine soils are in an arid or semiarid climate.with warm, dry summers and cool, moist winters. The average January temperature is 28 degrees F. and the average July temperature is 70 degrees F. The mean annual temperature is 45 to 54 degrees F. The frost-free season is 110 to 195 decays.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Burke, Powder, Shano, and Stanfield soils. Burke and Stanfield soils have a duripan. Powder soils have a mollic epipedon, have low exchangeable sodium and are on alluvial fans and bottomlands. Shano soils have low sodium content, an aridic moisture regime and are on terraces, hills and plateaus. Stanfield soils are on terraces. Burke soils are on uplands.
DRAINAGE AND PERMEABILITY: Somewhat poorly drained; slow runoff; moderate permeability. It has common to rare flooding during January to April.
USE AND VEGETATION: These soils are used mainly for native livestock grazing. Some areas are drained and reclaimed and used for irrigated cropland. Native vegetation is greasewood, big sagebrush, inland saltgrass, Basin wildrye inland, and other halophytic plants.
DISTRIBUTION AND EXTENT: Central and southeastern Washington and eastern Oregon. MLRA 7, 8. Series is of moderate extent.
MLRA OFFICE RESPONSIBLE: Portland, Oregon
SERIES ESTABLISHED: Baker Area, Oregon, 1941.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
Ochric epipedon - the zone from 0 to 9 inches
Exchangeable sodium - more than 15 percent in the upper 20 inches of the soil and becomes less with increasing depth
Particle-size control section - the zone from 10 to 40 inches