LOCATION ROCKSPRING WA
Established Series
IRD. SDH/TLS/JMB/SBC
09/2019
ROCKSPRING SERIES
Landscape--plateaus, hills
Landform--mesas, structural benches, hillslopes
Slope--0 to 12 percent
Parent material--loess over basalt
Mean annual precipitation--about 230 to 310 mm
Mean annual air temperature--about 9 degrees C
Depth class--moderately deep
Drainage class--well drained
Soil moisture regime--aridic
Soil temperature regime--mesic
Soil moisture subclass--xeric
TAXONOMIC CLASS: Fine-silty, mixed, superactive, mesic Calciargidic Argixerolls
TYPICAL PEDON: Rockspring silt loam in an area of rangeland, on a 3-percent, north-facing slope
A1--0 to 8 cm; silt loam, brown (10YR 5/3) dry, dark brown (10YR 3/3) moist; moderate very thin and thin platy structure; soft, very friable, nonsticky and nonplastic; common fine and medium roots; common very fine and fine pores; neutral (pH 7.0); clear smooth boundary
A2--8 to 18 cm; silt loam, brown (10YR 5/3) dry, dark brown (10YR 3/3) moist; moderate thin and medium platy structure; soft, very friable, nonsticky and nonplastic; common fine and medium roots; common very fine and fine pores; neutral (pH 7.0); clear smooth boundary
AB--18 to 30 cm; silt loam, brown (10YR 5/3) dry, dark brown (10YR 3/3) moist; moderate medium prismatic structure parting to weak medium subangular blocky; soft, friable, nonsticky and nonplastic; common fine and medium roots; common very fine and fine pores; neutral (pH 7.0); abrupt smooth boundary
Bt1--30 to 56 cm; silty clay loam, brown (10YR 5/3) dry, dark brown (10YR 3/3) moist; strong fine and medium subangular blocky structure; hard, very firm, sticky and plastic; common fine and medium roots; common very fine and fine pores; common moderately thick clay films on faces of peds and in pores; slightly alkaline (pH 7.6); gradual wavy boundary
Bt2--56 to 71 cm; silt loam, brown (10YR 5/3) dry, brown (10YR 4/3) moist; moderate medium subangular blocky structure; slightly hard, firm, slightly sticky and slightly plastic; few thin clay films on faces of peds and in pores; common fine and medium roots; common very fine and fine pores; slightly alkaline (pH 7.6); abrupt smooth boundary
2Bk--71 to 91 cm; extremely cobbly clay loam, very pale brown (10YR 7/3) dry, brown (10YR 5/3) moist; strong medium angular blocky structure; hard, very firm, sticky and plastic; common fine and medium roots; common very fine and fine pores; 30 percent gravel and 50 percent cobbles; violently effervescent on faces of peds, strongly effervescent in interior of peds; coatings of soft carbonates on faces of peds; moderately alkaline (pH 8.2); abrupt smooth boundary
2R--91 cm; fractured basalt
TYPE LOCATION: Yakama Nation, Yakima County, Washington, about 27 km southwest of Toppenish; about 610 m west and 180 m north of the southeast corner of section 35, T. 8 N., R. 19 E.; latitude 46.1302778, longitude -120.3955556, datum WGS 84 (coordinates estimated from section, township, and range)
RANGE IN CHARACTERISTICS:
Mean annual soil temperature at a depth of 50 cm--9 to 13 degrees C
Soil moisture--dry more than one-half the time the soil temperature is 5 degrees C or higher (about 105 to 120 consecutive days), moist in winter and early in spring in most years
Depth to secondary carbonates--38 to 97 cm
Depth to basalt--50 to 100 cm
Thickness of mollic epipedon--18 to 50 cm
Organic matter content--less than 1 percent in areas where mollic colors extend below a depth of 100 cm
Clay content in argillic horizon--18 to 35 percent
A horizon
Value--4 or 5 dry, 2 or 3 moist
Chroma--2 or 3 dry or moist
Reaction--6.6 to 7.8
Combined thickness--18 to 36 cm
AB horizon
Thickness--10 to 15 cm
Bt horizon
Value--5 or 6 dry, 3 or 4 moist
Chroma--2 or 3 dry or moist
Texture--silty clay loam, silt loam
Reaction--7.4 to 8.4
Combined thickness--33 to 53 cm
2Bk horizon
Value--5 to 7 dry, 3 or 4 moist
Chroma--3 or 4 dry or moist
Texture--loam, clay loam, silt loam, silty clay loam
Rock fragment content--20 to 80 percent gravel and cobbles
Calcium carbonate equivalent--15 to 35 percent
Reaction--7.9 to 9.0
Thickness--13 to 20 cm
COMPETING SERIES:
Hamrub--100 to 125 cm (deep) to a duripan
Kimama--no lithic contact within a depth of more than 150 cm
Marley--104 to 150 cm (deep) to a duripan
Polecat--100 to 150 cm (deep) to a paralithic contact (lacustrine deposits); 0 to 5 percent rock fragments throughout
GEOGRAPHIC SETTING:
Elevation--460 to 875 m
Mean annual precipitation--230 to 310 mm
Mean annual air temperature--8 to 9 degrees C
Frost-free season--100 to 145 days
GEOGRAPHICALLY ASSOCIATED SOILS:
Caliralls--no lithic contact within a depth of 100 cm or more
Prosser--coarse-loamy; no mollic epipedon or argillic horizon
Zen--fine-loamy; no lithologic discontinuity above lithic contact
DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY:
Drainage class--well drained
Saturated hydraulic conductivity (Ksat)--moderately high
USE AND VEGETATION:
Use--livestock grazing, wildlife habitat
Vegetation--bluebunch wheatgrass, Sandberg bluegrass, Wyoming big sagebrush
DISTRIBUTION AND EXTENT: South-central Washington in Yakima County, Washington; MLRA 8; small extent
SOIL SURVEY REGIONAL OFFICE (SSRO) RESPONSIBLE: Portland, Oregon
SERIES ESTABLISHED: Yakama Nation, Yakima County, Washington; 2014
REMARKS:
Diagnostic horizons and other features recognized in this pedon
*Mollic epipedon--zone from the surface to a depth of 30 cm
*Argillic horizon and particle-size control section--zone from 30 to 71 cm
*Calcic horizon--zone from 71 to 91 cm
*Depth to lithic contact--91 cm
National Cooperative Soil Survey
U.S.A.