LOCATION OEST NV+CA
Established Series
Rev. WED-JVC-JBF
04/2017
OEST SERIES
The Oest series consists of very deep, well drained soils that formed in alluvium derived from mixed igneous rocks. Oest soils are on fan remnants and stream terraces. Slopes are 0 to 50 percent. The mean annual precipitation is about 250 mm and the mean annual temperature is about 10 degrees C.
TAXONOMIC CLASS: Loamy-skeletal, mixed, superactive, mesic Aridic Argixerolls
TYPICAL PEDON: Oest bouldery sandy loam--rangeland. (Colors are for dry soil unless otherwise noted).
A--0 to 36 cm; grayish brown (10YR 5/2) bouldery sandy loam, very dark grayish brown (10YR 3/2) moist; moderate fine subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; common very fine roots; many very fine tubular pores; 15 percent gravel, 5 percent cobbles and 5 percent boulders and stones; slightly acid (pH 6.3); clear smooth boundary. (25 to 146 cm thick)
Bt1--36 to 71 cm; light brown (7.5YR 6/4) very gravelly sandy loam, brown (7.5YR 4/4) moist; weak coarse prismatic structure; slightly hard, friable, slightly sticky and slightly plastic; many very fine and fine roots; many very fine tubular pores; common distinct clay films on faces of peds and rock fragments; 30 percent gravel, 10 percent cobbles, and 5 percent stones; slightly acid (pH 6.5); gradual wavy boundary. (25 to 50 cm thick)
Bt2--71 to 102 cm; light brown (7.5YR 6/4) very gravelly sandy loam, brown (7.5YR 4/4) moist; massive; slightly hard, friable, slightly sticky and slightly plastic; common very fine and fine roots; many very fine tubular pores; few distinct clay films on rock fragments; 40 percent gravel, 10 percent cobbles, and 5 percent stones; slightly acid (pH 6.5); gradual wavy boundary. (10 to 20 cm thick)
C--102 to 152 cm; pale brown (10YR 6/3) extremely gravelly loamy sand, brown (7.5YR 4/4) moist; single grain; loose, nonsticky and nonplastic; common very fine and fine roots; many fine interstitial pores; 50 percent gravel, 10 percent cobbles, and 1 to 5 percent stones; slightly acid (pH 6.5).
TYPE LOCATION: Washoe County, Nevada; on the Toiyabe National Forest about 2 miles southwest of Verdi between Interstate 80 and the Nevada-California state line; approximately 600 feet south and 1,800 feet west of the east quarter corner of section 19, T. 19 N., R. 18 E.; USGS Mount Rose NW 7.5 minute topographic quadrangle; latitude 39 degrees 29 minutes 48 seconds N and longitude 119 degrees 59 minutes 57 seconds W; WGS84 Decimal Degrees 39.4966667 latitude, -119.9991667 longitude.
RANGE IN CHARACTERISTICS:
Soil moisture: Usually moist in winter and spring, dry in summer and fall; aridic moisture regime that borders on xeric.
Mean annual soil temperature: 10 to 11 degrees C.
Mollic epipedon thickness: 25 to 46 cm.
Depth to base of argillic horizon: 76 to 137 cm.
Particle-size control section - Clay content: 18 to 25 percent.
Rock fragments: 40 to 60 percent, mainly gravel. Lithology of fragments are mixed igneous rocks such as andesite, tuff, and granodiorite.
A horizon
Hue: 10YR or 7.5YR.
Value: 4 or 5 dry.
Chroma: 2 or 3, dry or moist.
Structure: Granular or subangular blocky structure.
Other features: 0 to 15 percent stones and boulders on the soil surface.
Bt horizons
Hue: 10YR through 5YR.
Value: 4 through 6 moist.
Chroma: 3 or 4, dry or moist.
Texture: Very gravelly sandy loam, very gravelly sandy clay loam, or very bouldery sandy clay loam.
Clay content: 18 to 25 percent.
Rock fragments: 40 to 60 percent.
Structure: Weak or coarse prismatic or angular blocky.
Reaction: Slightly acid or neutral.
Other features: Some pedons have hue of 5YR in these horizons.
C horizon (when present)
Hue: 10YR or 7.5YR.
Value: 5 through 7 dry, 4 or 5 moist.
Chroma: 2 through 4, dry or moist.
Texture: Very gravelly loamy sand, extremely gravelly sand, or very bouldery sand.
Rock fragments: 50 to 80 percent.
Reaction: Slightly acid or neutral.
Other features: Thin strata of gravelly sandy loam are in some pedons.
COMPETING SERIES: These are the
Ashue,
Badena,
Badenaugh,
Eaglerock,
Gitabyte,
Grinrod,
Ister,
Lemm,
Leviathan,
Nosrac,
Searles,
Searvar,
Shawmount,
Shree,
Shroe,
Tollgate,
Trid, and
Tristan series.
Ashue soils have depth to base of the argillic horizon that is less than 76 cm.
Badena soils are dominated by cobbles and have 60 to 85 percent rock fragments in the particle-size control section.
Badenaugh,
Leviathan,
Nosrac,
Shree, and
Shroe soils have more than 25 percent clay in the argillic horizon.
Eaglerock,
Searvar, and
Trid soils are moderately deep to paralithic contacts.
Gitabyte,
Grinrod,
Ister, and
Searles soils are moderately deep to lithic contacts.
Lemm soils average 10 to 18 percent clay in the particle-size control section.
Shawmount soils have a horizon with lamellae below the argillic horizon.
Tollgate soils have a mean annual soil temperature less than 10 degrees C.
Tristan soils are deep to lithic contacts.
GEOGRAPHIC SETTING: Oest soils are on fan remnants and stream terraces. They formed in alluvium derived from mixed igneous rocks that are mainly andesite, tuff, and granodiorite. Slopes are 0 to 50 percent. Elevations range from 1,375 to 1,740 meters. The climate is semiarid with cool, moist winters and warm, dry summers. The mean annual precipitation is 200 to 350 mm. The mean annual temperature is 7 to 11 degrees C. The frost-free period is 80 to 130 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the
Orr and
Springmeyer soils. Orr and Springmeyer soils have less than 35 percent rock fragments in the particle-size control section.
DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY: Well drained; low, medium, or high surface runoff; moderate permeability; moderately high saturated hydraulic conductivity.
USE AND VEGETATION: Oest soils are used principally for livestock grazing, recreation, and urban development. The vegetation is principally Wyoming big sagebrush, antelope bitterbrush, bottlebrush squirreltail, and cheatgrass.
DISTRIBUTION AND EXTENT: Western Nevada and eastern California. These soils are not extensive. MLRA 26.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Davis, California.
SERIES ESTABLISHED: Washoe County (South Part), Nevada, 1980.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
Mollic epipedon - The zone from the soil surface to 36 cm (A horizon).
Argillic horizon - The zone from 36 to 100 cm (Bt1 and Bt2 horizons).
Particle-size control section - The zone from 36 to 86 cm (Bt1 horizon and part of the Bt2 horizon).
ADDITIONAL DATA: User Pedon ID: 2006NV031086.
National Cooperative Soil Survey
U.S.A.