LOCATION PEOLA WAEstablished Series
TAXONOMIC CLASS: Fine-loamy, mixed, superactive, mesic Calcic Pachic Argixerolls
TYPICAL PEDON: Peola silt loam - cultivated (colors for dry soil unless otherwise noted).
Ap--0 to 7 inches; dark grayish brown (10YR 4/2) silt loam, very dark brown (10YR 2/2) moist; moderate fine and medium granular structure; hard, friable, sticky and plastic; many very fine roots; many very fine irregular pores; neutral (pH 7.2); abrupt smooth boundary. (6 to 9 inches thick)
A--7 to 14 inches; dark grayish brown (10YR 4/2) silt loam, very dark brown (10YR 2/2) moist; moderate medium prismatic structure parting to moderate medium and coarse subangular blocky; hard, friable, sticky and plastic; many very fine roots; many very fine irregular and few very fine tubular pores; mildly alkaline (pH 7.4); clear wavy boundary. (4 to 9 inches thick)
Bt1--14 to 19 inches; brown (10YR 4/3) silt loam, dark grayish brown (10YR 3/2) moist; moderate medium prismatic structure parting to moderate medium and coarse subangular blocky; hard, friable, sticky and plastic; many very fine roots; many very fine irregular and few tubular pores; common thin stress surfaces on faces of peds and few thin clay films lining pores, mildly alkaline (pH 7.4); clear wavy boundary. (3 to 6 inches thick)
Bt2--19 to 25 inches; brown (10YR 5/3) silt loam, dark brown (10YR 3/3) moist; moderate medium and coarse subangular blocky structure; hard, friable, sticky and plastic; many very fine roots; many very fine irregular and common tubular pores; common thin stress surfaces on faces of peds and few thin clay films lining pores, 10 percent pebbles; mildly alkaline (pH 7.4); abrupt wavy boundary. (4 to 10 inches thick)
2Bqk1--25 to 28 inches; white (10YR 8/2) very cobbly loam, pale brown (10YR 6/3) moist; massive; hard, firm, slightly sticky and slightly plastic; few very fine roots; common very fine irregular and few tubular pores; 25 percent lime-silica coated pebbles and 15 percent lime-silica coated cobbles; violently effervescent; moderately alkaline (pH 8.3); abrupt wavy boundary. (0 to 4 inches thick)
2Bqk2--28 to 36 inches; white (10YR 8/2) very cobbly loam, pale brown (10YR 6/3) moist; massive; slightly hard; friable, slightly sticky and slightly plastic; few very fine roots; common very fine irregular and few tubular pores; 25 percent indurated durinodes and lime-silica coated pebbles and 20 percent lime-silica coated cobbles; violently effervescent; moderately alkaline (pH 8.3); abrupt wavy boundary. (3 to 15 inches thick)
3R--36 inches; basalt.
TYPE LOCATION: Asotin County, Washington; about 16 miles west of Asotin; 600 feet east and 1,600 feet south of northwest corner sec. 27, T. 10 N., R. 43 E.
RANGE IN CHARACTERISTICS: Depth to a calcic horizon is 24 to 34 inches. Depth to a lithic contact with basalt is 30 to 40 inches. The mean annual soil temperature is about 49 degrees F. These soils are usually moist but are dry in all parts between 4 and 12 inches for 75 to 90 consecutive days following summer solstice. The particle-size control section averages 22 to 30 percent clay in the fine earth fraction and averages 5 to 25 percent basalt fragments and durinodes. The mollic epipedon is 24 to 34 inches thick and includes the entire solum above the calcic horizon.
The A horizon has value of 2 or 3 moist and chroma of 2 or 3 dry. Reaction is neutral or mildly alkaline.
The Bt horizon has value of 4 or 5 dry, 2 or 3 moist, and chroma of 2 or 3 dry and moist. Reaction is neutral or mildly alkaline. It is silt loam, silty clay loam, gravelly silt loam, or gravelly silty clay loam.
The 2Bqk horizon has value of 6 through 8 dry, 5 through 7 moist, and chroma of 1 through 3 dry and moist. It is very gravelly loam, extremely cobbly loam, or very cobbly loam. The coarse fragments include 20 to 35 percent lime-silica cemented durinodes and lime-silica coated basalt fragments. Reaction is moderately alkaline or strongly alkaline.
COMPETING SERIES: These are the Catheen, Crookston, Newell, and Roystone series. Catheen, Crookston, Newell, and Roystone soils are more than 40 inches deep to lithic contact.
GEOGRAPHIC SETTING: Peola soils are formed in loess and slope alluvium, and colluvium from weathered basalt on broad plateau tops. Slopes are 3 to 40 percent. Elevations range from 2,600 to 3,700 feet. Summers are warm and dry and winters are cool and moist. The average annual precipitation ranges from 15 to 18 inches. Mean annual temperature is about 47 degrees F. Frost-free season is 125 to 135 days.
GEOGRAPHICALLY ASSOCIATED SOILS: They are the Laufer, Neissenberg, Rockly, and Thiessen series AND THE COMPETING Catheen series. Laufer and Rockly soils have a lithic contact at a depth of less than 20 inches. Neissenberg and Spofmore soils have a natric horizon. Thiessen soils are clayey-skeletal.
DRAINAGE AND PERMEABILITY: Well drained; slow to medium runoff, moderate permeability.
USE AND VEGETATION: Used for cropland. Native vegetation is mainly bluebunch wheatgrass, Idaho fescue, Sandberg bluegrass, arrowleaf balsamroot, and western yarrow.
DISTRIBUTION AND EXTENT: Southeastern Washington; the series is of small extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Portland, Oregon
SERIES ESTABLISHED: Asotin County, Washington 1984.
REMARKS: Diagnostic horizons and features recognized in this soil are a mollic epipedon from the surface to 25 inches,an argillic horizon from 14 to 25 inches, a calcic horizon from 25 to 36 inches, and a lithic contact at 36 inches.