LOCATION LAS VEGAS               NV

Established Series
Rev. BS/RPZ
09/2015

LAS VEGAS SERIES

The Las Vegas series consists of shallow, well drained soils that formed in alluvium from limestone and lacustrine sediments on basin floor remnants and relict alluvial flats. Slopes range from 0 to 4 percent. Mean annual precipitation is about 5 inches; mean annual temperature is about 66 degrees F.

TAXONOMIC CLASS: Loamy, carbonatic, thermic, shallow Typic Petrocalcids

TYPICAL PEDON: Las Vegas gravelly fine sandy loam, open space. (Colors are for dry soil unless otherwise noted.)

Al--0 to 1 inch; very pale brown (10YR 7/3) gravelly fine sandy loam, yellowish brown (10YR 5/4) moist; strong medium platy structure; soft, very friable, slightly sticky and slightly plastic; few fine and many very fine vesicular pores; 30 percent pebbles; 40 percent calcium carbonate; violently effervescent; moderately alkaline (pH 8.4); abrupt smooth boundary. (l to 3 inches thick)

A2--1 to 3 inches; very pale brown (10YR 7/3) fine sandy loam, yellowish brown (10YR 5/4) moist; moderate thick platy structure; soft, very friable, nonsticky and nonplastic; few very fine, fine and medium roots; many very fine interstitial pores; l0 percent pebbles; 37 percent calcium carbonate; violently effervescent; strongly alkaline (pH 8.6); abrupt smooth boundary. (0 to 3 inches thick)

C--3 to 7 inches; very pale brown (10YR 7/3) fine sandy loam, yellowish brown (10YR 5/4) moist; weak medium subangular blocky structure; soft, very friable, nonsticky and nonplastic; many very fine and fine and common medium roots; few fine and medium tubular and many very fine and fine interstitial pores; 5 percent pebbles; 53 percent calcium carbonate; violently effervescent; strongly alkaline (pH 8.6); abrupt wavy boundary. (3 to l3 inches thick)

Ck--7 to 11 inches; very pale brown (10YR 7/3) gravelly sandy clay loam, pale brown (10YR 6/3) moist; massive; soft, very friable, slightly sticky and slightly plastic; many very fine and fine and common medium roots, mostly oriented horizontally at or near the hardpan; many very fine, common fine and medium interstitial pores; 25 percent gravel sized, hard calcium carbonate nodules; 68 percent calcium carbonate; violently effervescent; strongly alkaline (pH 8.6); abrupt wavy boundary. (3 to 5 inches thick)

Ckm--11 to 15 inches; white (N 8/) indurated lime hardpan; white (10YR 8/1) moist; strong very thick platy structure; extremely hard, extremely firm.

TYPE LOCATION: Clark County, Nevada; about l,300 feet north and 400 feet east of the southwest corner, of section 20, T. l9 S., R. 6l E., MDBM.

RANGE IN CHARACTERISTICS:

Soil moisture: Usually dry; moist during winter and for l0 to 20 days during July, August and September after convection storms. Soil temperature: 66 to 70 degrees F. Control section: Clay content: Averages less than l8 percent. Rock fragments: 5 to 35 percent, mostly gravel size caliche fragments. Calcium carbonate: Up to 85 percent, averaging more than 40 percent. Depth to petro-calcic horizon: 3 to l4 inches. Reaction: Moderately or strongly alkaline.

A horizon Hue: 7.5YR or l0YR. Value: 6 or 7 dry, 4 or 5 moist. Chroma: 3 or 4.

C horizon Hue: l0YR or 7.5YR. Value: 6, 7 or 8 dry, 5 or 6 moist. Chroma: 2, 3, 4 or 6. Texture: Fine sandy loam, loam or loamy fine sand. Ck horizon Hue: l0YR or 7.5YR. Value: 7 or 8 dry, 5, 6 or 7 moist. Chroma: 3 or 4. Texture: Sandy clay loam or loam with more than l8 percent clay. Other features: Small amounts of gypsum are present in some pedons.

Ckm horizon: Hue: l0YR, 7.5YR, 5YR or neutral. Value: 7 or 8 dry, 6, 7 or 8 moist. Chroma: 0, l, 2, 3 or 4. Structure: Massive or platy. Consistence: Commonly extremely hard and extremely firm; some pedons have thin layers that are very hard and very firm. Thickness of petro-calcic horizon: Thicker than 36 inches.

COMPETING SERIES: These are the Bard, Morman Mesa and Upton soils. Bard soils have petrocalcic horizons thinner than 36 inches. Bard and Morman Mesa soils lack horizons with more than l8 percent clay. Upton soils commonly have a cambic horizon, have petrocalcic horizons less than 35 inches thick, and receive 7 to l3 inches mean annual precipitation.

GEOGRAPHIC SETTING: Las Vegas soils are on remnants and relict alluvial flats, at elevations ranging from l,600 to 2,800 feet. Slopes are 0 to 4 percent. The soils formed in alluvium from limestone and lacustrine sediments. The mean annual precipitation is 4 to 6 inches. The mean annual temperature is 64 to 68 degrees F.; frost-free season is l80 to 260 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Glendale, Land, Skyhaven and Spring soils. The Glendale, Land, and Spring soils lack a petrocalcic horizon and have l8 thru 34 percent clay in the fine earth in the control sections. Glendale, Land and Spring soils have mixed mineralogy. Land soils have calcic horizons and Spring soils have gypsic horizons. Skyhaven soils have l8 thru 34 percent clay in the control section and have an argillic horizon above the petrocalcic horizon.

DRAINAGE AND PERMEABILITY: Well drained. Slow runoff. Permeability is moderately slow above the hardpan.

USE AND VEGETATION: Mostly open space, but some areas are being urbanized. Present vegetation is mainly creosotebush, white bursage, shadscale, ephedra and scattered mesquite.

DISTRIBUTION AND EXTENT: Southern Nevada. These soils are moderately extensive.

MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: PHOENIX, ARIZONA

SERIES ESTABLISHED: Clark County, Nevada. l923.

REMARKS: The type location was moved to better represent the current concept of the series.

Responsibility for this series was transferred from Davis to Phoenix 9/2015. The last revision to the series was 5/1997. ET

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National Cooperative Soil Survey
U.S.A.