LOCATION FLEX NV+CA
Established Series
Rev. WED-JVC-JBF
05/2016
FLEX SERIES
The Flex series consists of very shallow and shallow, well drained soils that formed in residuum derived from altered andesite and metavolcanic rock. Flex soils are on hills and mountains. Slopes are 8 to 50 percent. The mean annual precipitation is about 250 mm and the mean annual temperature is about 9 degrees C.
TAXONOMIC CLASS: Loamy-skeletal, mixed, superactive, mesic, shallow Xeric Haplargids
TYPICAL PEDON: Flex very gravelly sandy loam--suburban open space. (Colors are for dry soil unless otherwise noted).
A1--0 to 3 cm; grayish brown (10YR 5/2) very gravelly sandy loam, very dark grayish brown (10YR 3/2) moist; massive; soft, very friable, nonsticky and nonplastic; very few roots; many very fine interstitial pores; 35 percent gravel; slightly acid (pH 6.4); abrupt smooth boundary. (0 to 8 cm thick)
A2--3 to 8 cm; light brownish gray (10YR 6/2) very gravelly fine sandy loam, dark brown (10YR 3/3) moist; moderate medium platy structure; slightly hard, very friable, slightly sticky and nonplastic; common fine and very fine roots; common fine and very fine tubular pores; 35 percent gravel; slightly acid (pH 6.4); clear smooth boundary. (3 to 8 cm thick)
Bt1--8 to 13 cm; brown (10YR 5/3) very gravelly sandy loam, dark brown (10YR 3/3) moist; weak medium angular blocky structure; slightly hard, very friable, slightly sticky and slightly plastic; common fine and very fine roots; common fine and very fine tubular pores; common faint clay films bridging sand grains; 35 percent gravel; slightly acid (pH 6.5); clear smooth boundary. (3 to 8 cm thick)
Bt2--13 to 25 cm; brown (10YR 5/3) very gravelly sandy clay loam, dark brown (10YR 3/3) moist; weak fine angular blocky structure; hard, very friable, slightly sticky and slightly plastic; few fine and very fine roots; few fine and very fine tubular pores; common faint clay films on faces of peds, lining pores, and bridging sand grains; 40 percent gravel; slightly acid (pH 6.5); clear wavy boundary. (8 to 15 cm thick)
Cr--25 cm; highly weathered metavolcanic rock.
TYPE LOCATION: Washoe County, Nevada; in northwestern Reno about 0.5 mile southwest of the intersection of North Virginia Street and U.S. Highway 395; approximately 2,600 feet south and 2,600 feet west of the northeast corner of section 22, T. 20 N., R. 19 E.; USGS Reno 7.5 minute topographic quadrangle; latitude 39 degrees 35 minutes 07 seconds N and longitude 119 degrees 50 minutes 09 seconds W; UTM Zone 11, 256257e, 4385571n; WGS84 Decimal Degrees 39.5852778 latitude, -119.8358333 longitude.
RANGE IN CHARACTERISTICS:
Soil moisture: Usually moist from late November through May, dry from June through mid-October; aridic moisture regime that borders on xeric.
Mean annual soil temperature: 9 to 11 degrees C.
Ochric epipedon thickness: 3 to 13 cm.
Reaction: Slightly acid or neutral.
Depth to bedrock: 15 to 30 cm to a paralithic contact. The paralithic materials below the contact are weathered, altered volcanic or metavolcanic rock.
Particle-size control section - Clay content: Averages 15 to 25 percent.
Rock fragments: 35 to 50 percent, dominantly gravel. Lithology of fragments are altered andesite and metavolcanic rocks.
A horizons
Value: 5 or 6 dry, 3 or 4 moist.
Chroma: 2 or 3, dry or moist.
Bt horizons
Hue: 7.5YR or 10YR.
Value: 5 or 6 dry, 3 or 4 moist.
Chroma: 3 through 6, dry or moist.
Texture: Very gravelly sandy loam or very gravelly sandy clay loam.
Clay content: 18 to 27 percent.
Rock fragments: 35 to 50 percent, mainly gravel.
Structure: Weak to moderate, medium to fine angular blocky or subangular blocky.
COMPETING SERIES: These are the
Abalan,
Alcan,
Armoine,
Berit,
Bouncer,
Entero,
Ginex,
Harvan,
Penelas,
Ravenell,
Sedsked,
Soar,
Stodick, and
Zyzzi series.
Abalan and
Ginex soils have identifiable secondary carbonates.
Alcan,
Bouncer,
Entero, and
Zyzzi soils are intermittently moist for 10 to 20 days cumulative between July and October due to convection storms.
Armoine soils are 36 to 50 cm to the paralithic contact.
Berit soils have 50 to 80 percent rock fragments in the particle-size control section.
Harvan soils have densic materials at 30 to 50 cm.
Penelas soils are slightly alkaline through strongly alkaline and have 60 to 75 percent rock fragments that are dominantly shale channers in the particle-size control section.
Ravenell soils have 25 to 35 percent clay in the particle-size control section and have mean annual soil temperature of 12 to 14 degrees C.
Sedsked soils hare slightly alkaline or moderately alkaline.
Soar soils are dominated by fine granitic gravel, have high content of coarse and very coarse sand, and have hard, unweathered bedrock within 100 cm of the soil surface.
Stodick soils are 36 to 50 cm to the paralithic contact, have an abrupt boundary between the A and Bt horizons, and have 25 to 35 percent clay in the particle-size control section.
GEOGRAPHIC SETTING: Flex soils are on hills and mountains. They formed in residuum derived from altered andesitic volcanic and metavolcanic rock. Slopes are 8 to 50 percent. Elevations range from 1,460 to 2,164 meters. The climate is semiarid with cool, moist winters and warm, dry summers. The mean annual precipitation is 200 to 300 mm, the mean annual temperature is 7 to 9 degrees C., and the frost-free period is 80 to 110 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the
Wedekind,
Yuko, and
Indiano soils. Wedekind and Yuko soils are loamy. Indiano soils are fine-loamy, moderately deep to lithic contacts, and have mollic epipedons.
DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY: Well drained; very high surface runoff; moderate permeability; moderately high saturated hydraulic conductivity.
USE AND VEGETATION: Flex soils are used for wildlife habitat, watershed, and urban development. The vegetation is principally Wyoming big sagebrush, green ephedra, purple sage, desert needlegrass, antelope bitterbrush, and cheatgrass. This pedon is correlated to R0XY011NV, South Slope 8-12" P.Z.
DISTRIBUTION AND EXTENT: Western Nevada and eastern California. These soils are moderately 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:
Ochric epipedon - The zone from the soil surface to 8 cm (A1 and A2 horizons).
Argillic horizon - The zone from 8 to 25 cm (Bt1 and Bt2 horizons).
Paralithic contact - The boundary at 25 cm to underlying soft, weathered bedrock (Cr layer).
Particle-size control section - The zone from the soil surface to 25 cm (A1, A2, Bt1, and Bt2 horizons).
ADDITIONAL DATA: User pedon ID 2006NV031037.
National Cooperative Soil Survey
U.S.A.