LOCATION RALLS WAEstablished Series
TAXONOMIC CLASS: Fine-loamy, mixed, superactive, mesic Aridic Argixerolls
TYPICAL PEDON: Ralls very cobbly silt loam- rangeland. (Colors are for dry soil unless otherwise noted. All textures are apparent field textures).
A--0 to 10 inches; grayish brown (10YR 5/2) very cobbly silt loam, very dark grayish brown (10YR 3/2) moist; moderate fine granular structure; slightly hard, friable, slightly sticky and slightly plastic; many fine roots; many medium and coarse tubular pores; 15 percent gravel, 5 percent cobbles and 5 percent stones; slightly alkaline (pH 7.6); gradual smooth boundary. (8 to 12 inches thick)
Bt--10 to 20 inches; brown (10YR 4/3) gravelly clay loam, dark brown (10YR 3/3) moist; moderate medium subangular blocky structure; hard, firm, moderately sticky and moderately plastic; common fine roots; few fine and very fine tubular pores; many distinct continuous clay films on faces of peds and on rock fragments; 20 percent gravel and 5 percent cobbles; slightly alkaline (pH 7.6); clear wavy boundary. (8 to 20 inches thick)
BCt--20 to 32 inches; yellowish brown (10YR 5/4) very gravelly silt loam, brown (10YR 4/3) moist; weak medium subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; few fine roots; few medium tubular pores; few faint discontineous clay films on peds and rock fragments; 25 percent gravel and 10 percent cobbles; slightly alkaline (pH 7.8); gradual smooth boundary. (0 to 20 inches thick)
C--32 to 60 inches; yellowish brown (10YR 5/4) very gravelly silt loam, dark yellowish brown (10YR 4/4) moist; massive; slightly hard, friable, slightly sticky and slightly plastic; few fine roots; common medium and fine tubular pores; 40 percent angular basalt gravel and 15 percent cobbles; moderately alkaline (pH 8.0).
TYPE LOCATION: Douglas County, Washington; 1,200 feet north and 1,200 feet east of southwest corner section 6, T. 23 N., R. 21 E.
RANGE IN CHARACTERISTICS: The mean annual soil temperature is 49 to 53 degrees F. These soils are dry more than one-half the time the soil temperature is above 41 degrees F, about 105 to 120 consecutive days in most years. The mollic epipedon is 10 to 20 inches thick. The particle-size control averages 15 to 35 percent rock fragments and 18 to 35 percent clay. Depth to bedrock is over 40 inches. Soft powdery segregated lime is at a depth of 36 to 60 inches in some pedons.
The A horizon has value of 4 or 5 dry, 2 or 3 moist and chroma of 2 or 3 dry or moist. Texture is very cobbly silt loam, stony silt loam, gravelly silt loam or silt loam. Reaction is slightly or moderately alkaline.
The Bt horizon and BCt horizon, when present, has value of 4 or 5 dry, 3 or 4 moist and chroma of 3 or 4 dry, 2 to 4 moist. Texture of the fine-earth fraction is clay loam, silt loam or loam with 10 to 45 percent cobbles and gravel. It has continuous or patchy clay films. Reaction is slightly alkaline or moderately alkaline.
A Bk horizon is present in some pedons with value of 5 or 6 dry, 4 moist and chroma of 3 or 4 dry or moist. Texture of the fine-earth fraction is silt loam or clay loam with 15 to 25 percent gravel and 0 to 10 percent cobbles. Calcium carbonate equivalent is 1 to 5 percent. Reaction is moderately alkaline or strongly alkaline.
The C horizon has value of 5 to 7 dry, 3 to 5 moist and chroma of 3 or 4 dry or moist. Texture of the fine-earth fraction is is clay loam or silt loam with 25 to 60 percent gravel and cobbles. Calcium carbonate equivalent is 0 to 5 percent. Reaction is moderately alkaline or strongly alkaline.
COMPETING SERIES: These are the
Bissell,
Bjork,
Cowiche,
Dodes,
Fernpoint,
Hullsgulch,
Indiano,
Jerusalem,
Margerum,
Madras,
Noslo,
Orr,
Pahrange,
Quailridge (T),
Quiero,
Shoebend,
Simcoe,
Springmeyer,
Truax,
Uhaldi, and
Wenatchee series.
Bissell soils particle-size control section has 0 to 5 percent rock fragments of granitic origin; significant mica particles throughout solum
Bjork soils 20 to 40 inches to a paralithic contact (schist)
Cowiche soils 40 to more than 60 inches to paralithic contact (sandstone or schist); particle-size control section has 0 to 5 percent rock fragments
Dodes soils 20 to 40 inches to a paralithic contact (sandy tuff)
Fernpoint soils 20 to 30 inches to contrasting sandy-skeletal material
Hullsgulch soils particle-size control section has 0 to 15 percent rock fragments of granitic origin; lamella (E&Bt horizons) occur below argillic horizon
Indiano soils 20 to 40 inches to a lithic contact (rhyolite)
Jerusalem soils particle-size control section has 5 to 15 percent rock fragments of granitic origin; soil reaction is slightly acid or neutral throughout
Margerum soils particle-size control section has 15 to 35 percent pumice parafragments
Madras soils 22 to 40 inches to a lithic contact (basalt)
Noslo soils 20 to 40 inches to a paralithic contact (granite); particle-size control section has 0 to 15 percent rock fragments (fine gravel) of granitic origin
Orr soils particle-size control section has 10 to 25 percent rock fragments of andesite or granodiorite origin and are sandy loam or sandy clay loam; soil reaction is neutral or slightly acid throughout
Pahrange soils 20 to 40 inches to a paralithic contact (rhyolite)
Quailridge soils particle-size control section has 5 to 25 percent rock fragments of granitic origin and are sandy clay loam or coarse sandy loam texture; lamella (E&Bt horizons) occur below argillic horizon
Quiero soils 20 to 40 inches to a lithic contact (welded tuff)
Shoebend soils 20 to 40 inches to a lithic contact (granodiorite)
Simcoe soils 20 to 40 inches to a lithic contact (basalt)
Springmeyer soils soil reaction of A horizon of slightly acid or neutral; dry for more than 120 days
Truax soils dry for more than 120 days; Bq horizons with discontinuous laminar capping occur below the argillic horizon
Uhaldi soils 20 to 40 inches to a paralithic contact (tuffaceous sandstone)
Wenatchee soils particle-size control section has 5 to 15 percent rock fragments and are sandy clay loam or clay loam texture
GEOGRAPHIC SETTING: These soils are on hillsides, canyon side slopes, and footslopes and side slopes of plateaus. Elevations are 400 to 3,400 feet. Slopes are 1 to 90 percent. These soils formed in colluvium derived from basalt mixed with loess. They occur in a cool, dry semiarid climate. The mean annual precipitation is 9 to 14 inches. The average January temperature is 22 degrees F. and the average July temperature is 73 degrees F. The mean annual temperature is 48 to 50 degrees F. The frost-free season is 125 to 180 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Bakeoven, Lickskillet, Renslow, and Zen soils. Bakeoven and Lickskillet soils are on uplands and are less than 20 inches deep to basalt. Renslow soils are on plateaus and hills and are coarse-silty. Zen soils are on plateaus and are 20 to 40 inches deep to a lithic contact.
DRAINAGE AND PERMEABILITY: Well drained; slow to very rapid runoff; moderately slow permeability.
USE AND VEGETATION: These soils are used for livestock grazing. The native vegetation is bluebunch wheatgrass, Idaho fescue, needleandthread, phlox, and Wyoming big sagebrush.
DISTRIBUTION AND EXTENT: Central Washington. MLRA 8. Ralls soils are of moderate extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Portland, Oregon
SERIES ESTABLISHED: Douglas County, Washington, 1978.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
Mollic epipedon the zone from 0 to 20 inches
Argillic horizon the zone from 10 to 32 inches
Particle-size control section - the zone from 10 to 30 inches (Bt and part of the BCt horizon).