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 15 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, 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 21 inches thick)
C1--43 to 54 inches; pale brown (10YR 6/3) silt loam, 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. (0 to 20 inches thick)
C2--54 to 65 inches; pale brown (10YR 6/3) silt loam, 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).
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. A duripan or basalt bedrock may occur at depths of over 40 inches.
The Ap or A horizon has value of 4 or 5 dry and chroma of 2 or 3 moist. Reaction is neutral or slightly alkaline.
The AB horizon, when present, has value of 4 or 5 dry, 3 or 4 moist and chroma of 2 to 4 dry and moist. Reaction is neutral or slightly alkaline.
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. Reaction is neutral to moderately alkaline.
The Bk horizon and C horizon, when present, have value of 4 to 7 dry, 4 or 5 moist and chroma of 2 to 4 dry and moist. Texture is silt loam, fine sandy loam, or very fine sandy loam. Reaction is moderately or strongly alkaline.
COMPETING SERIES: These are the
Ellisforde,
Hodad (T),
Mikkalo, and
Neeley series.
Ellisforde soils 20 to 40 inches to laminated lacustrine sediments
Hodad soils 20 to 40 inches to a lithic contact (basalt); 7 to 20 inches to a calcic horizon with 15 to 30 percent calcium carbonate equivalent
Mikkalo soils 20 to 40 inches to a lithic contact (basalt)
Neeley soils 7 to 26 inches to a calcic horizon with 15 to 30 percent calcium carbonate equivalent
GEOGRAPHIC SETTING: Ritzville soils are on uplands including plateaus, benches, and canyon side slopes. Elevations are 700 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. and average July temperature is 71 degrees F. The mean annual temperature is 48 to 52 degrees F. The frost-free season is 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; MLRA 8. Series is extensive.
MLRA OFFICE RESPONSIBLE: Portland, Oregon
SERIES ESTABLISHED: Franklin County, Washington, 1914.
REMARKS: Diagnostic horizons and features recognized in this pedon:
Mollic epipedon - from the surface to 18 inches
Cambic horizon - from 18 to 36 inches
Lime accumulation - from 36 to 43 inches with less than 15 percent calcium carbonate equivalent
Particle-size control section - 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.