LOCATION CLIFFDOWN               NV+UT

Established Series
Rev. LNL/PWB/JVC/JBF
06/2016

CLIFFDOWN SERIES

The Cliffdown series consists of very deep, somewhat excessively drained soils that formed in alluvium derived from mixed rocks. Cliffdown soils are on fan remnants, fan aprons, fan skirts, inset fans, and beach plains. Slopes are 0 to 15 percent. The mean annual precipitation is about 175 mm and the mean annual temperature is about 12 degrees C.

TAXONOMIC CLASS: Loamy-skeletal, mixed, superactive, calcareous, mesic Typic Torriorthents

TYPICAL PEDON: Cliffdown gravelly sandy loam--rangeland. (Colors are for dry soil unless otherwise noted.)

A--0 to 8 cm; light brownish gray (10YR 6/2) gravelly sandy loam, brown (10YR 4/3) moist; weak thin platy structure; soft, very friable, nonsticky and nonplastic; common very fine and fine roots; common very fine and fine tubular, and many very fine interstitial pores; 30 percent gravel; strongly effervescent; strongly alkaline (pH 8.6); clear smooth boundary. (5 to 15 cm thick)

C1--8 to 33 cm; light brownish gray (10YR 6/2) gravelly fine sandy loam, brown (10YR 4/3) moist; massive; slightly hard, very friable, slightly sticky and slightly plastic; many very fine and fine, and few medium roots; many very fine tubular and interstitial pores; 30 percent gravel; violently effervescent; strongly alkaline (pH 8.6); clear smooth boundary. (15 to 30 cm thick)

C2--33 to 50 cm; light gray (10YR 7/2) very gravelly fine sandy loam, brown (10YR 5/3) moist; massive; soft, very friable, slightly sticky and nonplastic; many very fine and fine, and few medium roots; many very fine interstitial pores; 40 percent gravel; violently effervescent; strongly alkaline (pH 8.6); clear smooth boundary. (15 to 53 cm thick)

C3--50 to 81 cm; light gray (10YR 7/2) gravelly fine sandy loam, brown (10YR 5/3) moist; massive; soft, very friable, slightly sticky and nonplastic; many very fine and fine roots; many very fine and fine interstitial pores; 30 percent gravel; violently effervescent; strongly alkaline (pH 8.8); clear smooth boundary. (0 to 64 cm thick)

C4--81 to 107 cm; light gray (10YR 7/2) very gravelly fine sandy loam, brown (10YR 5/3) moist; massive; soft, very friable, slightly sticky and nonplastic; many very fine and fine roots; many very fine and fine interstitial pores; 50 percent gravel; violently effervescent; strongly alkaline (pH 8.8); clear smooth boundary. (0 to 89 cm thick)

C5--107 to 152 cm; light gray (10YR 7/2) gravelly sandy loam, brown (10YR 4/3) moist; massive; soft, very friable, nonsticky and nonplastic; many very fine and fine roots; many very fine and fine interstitial pores; 30 percent gravel; violently effervescent; strongly alkaline (pH 8.5).

TYPE LOCATION: Lincoln County, Nevada; in Sand Spring Valley about 18 miles north-northeast of Rachel; approximately 2,100 feet west and 2,120 feet south of the northeast corner of section 33, T. 1 N., R. 56 E; USGS McCutchen Spring 7.5 minute topographic quadrangle; latitude 37 degrees 54 minutes 21 seconds N and longitude 115 degrees 41 minutes 2 seconds W; WGS84 Decimal Degrees 37.9058333latitude, -115.6838889 longitude.

RANGE IN CHARACTERISTICS:
Soil moisture: Usually moist in some part of the moisture control section for only short periods during winter and early spring and intermittently moist in surface horizons for 10 to 20 days cumulative between July and September following convection storms; typic aridic soil moisture regime.
Mean annual soil temperature: 12 to 15 degrees C.
Reaction: Moderately alkaline or strongly alkaline.
Effervescence: Slightly effervescent through violently effervescent.
Calcium carbonate equivalent: 15 to 40 percent.
Other features: Some pedons have thin Bk horizons with few carbonate coats on rock fragments.

Particle-size control section - Clay content: 5 to 18 percent;
Rock fragments: Averages 35 to 50 percent, mainly gravel. Lithology of fragments is rocks of mixed origin and include limestone, tuff, and quartzite.

A horizon
Hue: 10YR or 7.5YR.
Value: 6 or 7 dry, 3 through 5 moist.
Chroma: 2 through 4, dry or moist.

C horizons
Value: 6 or 7 dry, 4 or 5 moist.
Chroma: 2 or 3, dry or moist.
Texture: Gravelly sandy loam, very gravelly sandy loam, or very gravelly fine sandy loam.
Consistence: Soft or slightly hard dry, nonsticky or slightly sticky and nonplastic or slightly plastic wet.

COMPETING SERIES: These are the Clifterson, Clowfin, Defler, Dient, Myton, and Trocken series.

Clifterson soils have 18 to 35 percent clay in the particle-size control section. Clowfin soils have mean annual soil temperature of 8 to 12 degrees C. Defler soils have Bk and Bkq horizons, 5 to 15 percent durinodes below 30 cm, and mean annual soil temperature of 8 to 11 degrees C. Dient soils have 18 to 27 percent clay in the particle-size control section. Myton soils have unconformable gravel and sand at 64 cm. Trocken soils have thin Bw horizons and are not intermittently moist for 10 to 20 days cumulative between July and October.

GEOGRAPHIC SETTING: Cliffdown soils are on fan remnants, fan aprons, fan skirts, inset fans, and beach plains. These soils formed in alluvium derived from mixed rocks. Slopes are 0 to 15 percent. Elevations range from 1,280 to 1,860 meters. The climate is arid with cool, moist winters and hot, dry summers. The mean annual precipitation is 150 to 200 mm, the mean annual temperature is 10 to 13 degrees C., and the frost-free period is 130 to 150 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Crystal Springs, Monte Cristo, Sierocliff, and Tickapoo soils. Crystal Springs and Sierocliff soils have petrocalcic horizons. Monte Cristo soils are loamy, shallow to duripans, and have natric horizons. Tickapoo soils are clayey, shallow to duripans, and have natric horizons.

DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY: Somewhat excessively drained; very low or low surface runoff; high saturated hydraulic conductivity.

USE AND VEGETATION: Cliffdown soils are used for livestock grazing and wildlife habitat. The vegetation is mainly winterfat, bud sagebrush, and Indian ricegrass.

DISTRIBUTION AND EXTENT: South-central Nevada and western Utah in the Great Basin section of the Basin and Range physiographic province. These soils are extensive with about 300,000 acres of the series mapped to date. The series concept and main acreage is in MLRA 29, while other acreage occurs in MLRAs 28A and 28B.

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

SERIES ESTABLISHED: Lincoln County (Meadow Valley Area), Nevada, 1971.

REMARKS: Diagnostic horizons and features recognized in this pedon are:
Ochric epipedon - The zone from the soil surface to 18 cm (A and part of C1 horizons).
Particle-size control section - The zone from 25 to 100 cm (C2, C3, parts of the C1 and C4 horizons).

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National Cooperative Soil Survey
U.S.A.