LOCATION RITZVILLE WA+OREstablished Series
TAXONOMIC CLASS: Coarse-silty, mixed, superactive, mesic Calcidic Haploxerolls
TYPICAL PEDON: Ritzville silt loam - cultivated. (Colors are for dry soil unless otherwise stated. All textures are apparent field textures).
Ap--0 to 9 inches; grayish brown (10YR 5/2) silt loam, very dark grayish brown (10YR 3/2) moist; weak fine granular structure; soft, very friable, slightly sticky and slightly plastic; common roots; many very fine and fine irregular pores; neutral (pH 6.8); abrupt smooth boundary. (6 to 13 inches thick)
AB--9 to 18 inches; brown (10YR 5/3) silt loam, dark brown (10YR 3/3) moist; weak medium and coarse prismatic structure; slightly hard, very friable, slightly sticky and slightly plastic; common roots; many fine tubular pores; slightly alkaline (pH 7.8); clear wavy boundary. (0 to 12 inches thick)
Bw--18 to 36 inches; brown (10YR 5/3) silt loam, dark brown (10YR 4/3) moist; weak medium and coarse prismatic structure; slightly hard, very friable, slightly sticky and slightly plastic; common roots; many fine tubular pores; slightly alkaline (pH 7.8); abrupt wavy boundary. (13 to 34 inches thick)
Bk--36 to 43 inches; pale brown (10YR 6/3) silt loam, brown (10YR 5/3) moist; massive; slightly hard, very friable, slightly sticky and slightly plastic; common roots; many very fine tubular pores; segregated lime in pores and root channels; violently effervescent; moderately alkaline (pH 8.2); gradual wavy boundary. (6 to 19 inches thick)
C1--43 to 54 inches; pale brown (10YR 6/3) silt loam, dark brown (10YR 4/3) moist; massive; slightly hard, very friable, slightly sticky and slightly plastic; few roots; common very fine tubular pores; strongly effervescent; strongly alkaline (pH 8.5); abrupt irregular boundary. (8 to 20 inches thick)
C2--54 to 65 inches; pale brown (10YR 6/3) silt loam, dark brown (10YR 4/3 moist; massive, hard, very friable, slightly sticky and slightly plastic; few roots; common very fine tubular pores; strongly effervescent; strongly alkaline (pH 8.5); abrupt irregular boundary. (8 to 20 inches thick)
TYPE LOCATION: Adams County, Washington; 190 feet east and 770 feet north of southwest corner sec. 35, R. 20 N., R. 35 E. W.M.
RANGE IN CHARACTERISTICS: The mean annual soil temperature is 49 to 54 degrees F. The soil is usually dry in all parts between depths of 4 and 12 inches for one-half to three-fourths of the time when the soil temperature is above 41 degrees F. Depth to the Bk horizon and soft powdery secondary carbonates is 19 to 44 inches. The mollic epipedon is 10 to 20 inches thick. The particle-size control section contains less than 15 percent fine sand or coarser including rock fragments. Clay content is 5 to 10 percent. Some pedons are stratified at depths of 40 to 60 inches, and a duripan may occur at depths of over 40 inches.
The Ap and AB horizons have value of 4 or 5 dry, and chroma of 2 or 3 dry or moist. The Ap horizon has granular or subangular blocky structure.
The Bw horizon has value of 4, 5, or 6 dry, 3 or 4 moist and chroma of 3 or 4 dry and moist. It has weak prismatic or subangular blocky structure, and is neutral to moderately alkaline.
The Bk and C horizons have value of 4 to 7 dry, 4 or 5 moist and chroma of 2 to 4 dry and moist. It is silt loam, fine sandy loam, or very fine sandy loam. It is moderately or strongly alkaline.
COMPETING SERIES: These are the Ellisforde, Mikkalo, and Neeley series. Ellisforde soils have laminated lake silts at depths of 20 to 40 inches. Mikkalo soils have a lithic contact at 20 to 40 inches. Neeley soils have a calcic horizon at a depth of about 11 inches.
GEOGRAPHIC SETTING: Ritzville soils are on uplands including plateaus, benches, and canyon side slopes. Elevations are 800 to 3,000 feet. Slopes range from 0 to 70 percent. These soils formed in loess. They have a small amount, less than 20 percent, of volcanic ash in the surface layer. These soils are in a semiarid climate with cool, moist winters and warm, dry summers. The average annual precipitation is 9 to 12 inches. Average January temperature is 28 degrees F., average July temperature is 71 degrees F., and average annual temperature is 48 to 52 degrees F. Frost-free season is about 130 to 180 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Esquatzel, Gravden, Mikkalo, Ritzcal, and Willis soils. Esquatzel soils are on bottomlands and have irregular distribution of organic matter. Gravden soils are on terraces and are loamy-skeletal and have a duripan. Mikkalo soils are on uplands and are 20 to 40 inches deep to bedrock. Ritzcal soils are on uplands and are calcareous throughout. Willis soils are on terraces and have a lime-silica duripan at a depth of 20 to 40 inches.
DRAINAGE AND PERMEABILITY: Well drained; very slow to rapid runoff; moderate permeability.
USE AND VEGETATION: Dryland wheat production and some livestock grazing. Native vegetation is bluebunch wheatgrass, Sandberg bluegrass, Wyoming big sagebrush, and yarrow.
DISTRIBUTION AND EXTENT: Eastern Washington and eastern Oregon. Series is extensive.
MLRA OFFICE RESPONSIBLE: Portland, Oregon
SERIES ESTABLISHED: Franklin County, Washington, 1914.
REMARKS: Diagnostic horizons and features recognized in this pedon are a mollic epipedon from the surface to 18 inches, a cambic horizon from 18 to 36 inches, and a zone of lime accumulation with less than 15 percent calcium carbonate from 36 to 43 inches. The particle-size control section is the zone from 10 to 40 inches (part of the AB, the Bw and part of the Bk horizons).
ADDITIONAL DATA: Lab data is available for this series. NSSL pedon numbers 40A0964, 40A0981, 80P0304, 92P0077, and 92P0680.