LOCATION RATLEFLAT               NV

Established Series
Rev: EWB/DJM/WED/JBF
06/2017

RATLEFLAT SERIES

The Ratleflat series consists of very deep, well drained soils that formed in alluvium derived predominantly from granitic rocks. Ratleflat soils are on fan piedmonts. Slopes are 2 to 15 percent. The mean annual precipitation is about 250 mm and the mean annual temperature is about 12 degrees C.

TAXONOMIC CLASS: Coarse-loamy, mixed, superactive, mesic Xeric Haplargids

TYPICAL PEDON: Ratleflat gravelly loamy sand--rangeland. (Colors are for dry soil unless otherwise noted.)

A1--0 to 8 cm; light brownish gray (10YR 6/2) gravelly loamy sand, dark grayish brown (10YR 4/2) moist; weak medium subangular blocky structure; soft, very friable, nonsticky and nonplastic; common very fine and fine roots; common very fine interstitial and few very fine tubular pores; 15 percent gravel; neutral (pH 6.8); clear smooth boundary. (3 to 10 cm thick)

A2--8 to 23 cm; pale brown (10YR 6/3) gravelly loamy sand, brown (10YR 4/3) moist; weak medium subangular blocky structure; soft, very friable, nonsticky and nonplastic; common very fine and fine roots; common very fine interstitial and few very fine tubular pores; 15 percent gravel; neutral (pH 6.8); clear wavy boundary. (5 to 20 cm thick)

Bt--23 to 46 cm; light yellowish brown (10YR 6/4) gravelly sandy loam, dark yellowish brown (10YR 4/4) moist; weak medium subangular blocky; soft, very friable, nonsticky and nonplastic; common very fine and fine roots; common very fine and fine tubular and few very fine interstitial pores; 20 percent gravel; few thin clay films on faces of peds; neutral (pH 6.8); clear wavy boundary. (20 to 30 cm thick)

Btq--46 to 56 cm; light yellowish brown (10YR 6/4) gravelly sandy loam, dark yellowish brown (10YR 4/4) moist; massive; soft, very friable, nonsticky and nonplastic; common very fine and few fine roots; common very fine interstitial pores; 30 percent gravel; 20 percent weak 1 to 5 cm thick silica durinodes and discontinuous weak silica cementation, few thin clay films bridging sand grains; neutral (pH 6.6); clear wavy boundary. (0 to 13 cm thick)

2C1--56 to 81 cm; pale brown (10YR 6/3) very gravelly loamy coarse sand, brown (10YR 4/3) moist; single grained; loose, nonsticky and nonplastic; common very fine and few fine roots; many very fine interstitial pores; 40 percent gravel; neutral (pH 6.8); clear wavy boundary. (25 to 76 cm thick)

2C2--81 to 152 cm; pale brown (10YR 6/3) extremely gravelly coarse sand, brown (10YR 5/3) moist; single grained; loose, nonsticky and nonplastic; common very fine and few fine roots; many very fine and few fine interstitial pores; 60 percent gravel, 15 percent weak 1.3 to 2.5 cm silica durinodes; neutral (pH 7.0).

TYPE LOCATION: Mineral County, Nevada; in Rattlesnake Flat, about 100 feet south and l50 feet west of the northwest corner of Section 7, T. 5 N., R. 32 E.; USGS Rattlesnake Flat, NV 7.5 minute topographic quadrangle; latitude 38 degrees 18 minutes 47 seconds N and longitude 118 degrees 27 minutes 19 seconds W; WGS84 Decimal Degrees 38.3130556 latitude, -118.4541667 longitude.

RANGE IN CHARACTERISTICS:
Soil moisture: Moist in winter and spring, dry in summer and autumn except moist for 10 to 20 days cumulative between July and October due to convection storms; aridic soil moisture regime bordering on xeric.
Mean annual soil temperature: 12 to 15 degrees C.
Depth to unconformable 2C horizon: 38 to 76 cm.

Particle-size control section - Clay content: Averages 10 to 18 percent.
Rock fragments: Averages 15 to 35 percent, predominantly 2 to 5 mm angular gravel.

A horizon
Value: Dominantly 6 dry and 4 moist, but may be 5 dry and 3 moist in upper 5 to 8 cm.
Chroma: 2 or 3.

Bt horizon
Chroma: 3 or 4 dry or moist.
Texture: Sandy loam or coarse sandy loam.

Btq horizon
Cementation: Where present, has weak to strong durinodes or weak to strong discontinuous silica cementation.
Texture: Sandy loam or coarse sandy loam.

2C horizon
Value: 4 or 5 moist.
Chroma: 2 or 3.
Texture: Stratified loamy sand to coarse sand.
Rock fragments: Averages 35 to 60 percent, predominantly 2 to 5 mm gravel.
Cementation: Has up to 15 percent durinodes or weak discontinuous silica cementation, but cementation is absent in some pedons.
Reaction: Neutral or slightly alkaline.

COMPETING SERIES: These are the Deadyon, Saralegui and Tarloc series. Deadyon soils have 5 to 15 percent fine gravel in the particle-size control section. Saralegui soils have less than 35 percent rock fragments in the C horizon and are not moist for 10 to 20 days from July to October. Tarloc soils have bedrock at a depth of 50 to 100 cm.

GEOGRAPHIC SETTING: Ratleflat soils are on alluvial fan piedmonts. These soils formed in alluvium from predominantly granitic rocks. Slopes are 2 to 15 percent. Elevations are 1,505 to 1,950 meters. The climate is semiarid with warm, dry summers and cool, moist winters. The mean annual precipitation is 200 to 300 mm, mean annual temperature is 10 to 12 degrees C, and the frost-free season is 100 to 130 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Wiskiflat and Fawin soils. Wiskiflat soils lack a cambic horizon. Fawin soils have less than 35 percent rock fragments in the control section.

DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY: Well drained; slow runoff; high saturated hydraulic conductivity.

USE AND VEGETATION: Rangeland and wildlife habitat. The vegetation is mainly Wyoming big sagebrush, Indian ricegrass, galleta, Nevada ephedra and spiny hopsage.

DISTRIBUTION AND EXTENT: West-central Nevada. These soils are not extensive. MLRA 27.

MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Davis, California

SERIES ESTABLISHED: Mineral County Area, Nevada, 1985.

REMARKS: Diagnostic horizons and features recognized in this pedon are:
Ochric epipedon - The zone from the soil surface to 23 cm. (A1 and A2 horizons).
Argillic horizon - The zone from 23 to 56 cm (Bt and Btq horizons).
Particle-size control section - The zone from 23 to 56 cm (Bt and Btq horizons).

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National Cooperative Soil Survey
U.S.A.