LOCATION ALAMOROAD               NV

Established Series
Rev. LJL/CAH/ET
04/2015

ALAMOROAD SERIES

The Alamoroad series consists of very deep, well drained soils that formed in alluvium derived from limestone. Alamoroad soils are on fan remnants. Slope ranges from 4 to 15 percent. The mean annual precipitation is about 150 millimeters and the mean annual air temperature is about 15 degrees C.

TAXONOMIC CLASS: Loamy-skeletal, carbonatic, thermic Petronodic Haplocalcids

TYPICAL PEDON: Alamoroad very gravelly silt loam - rangeland and wildlife habitat. Colors are for dry soil unless otherwise noted. The soil surface is covered by approximately 70 percent gravel.

A--0 to 5 centimeters, (0 to 2 inches); pale brown (10YR 6/3) very gravelly silt loam, brown (10YR 4/3) moist; moderate medium subangular blocky structure; moderately hard, very friable, slightly sticky and slightly plastic; common very fine roots; few fine tubular and many very fine interstitial pores; 5 percent fine gravel, 40 percent medium and coarse gravel; violently effervescent; moderately alkaline (pH 8.2); abrupt smooth boundary. (4 to 10 centimeters thick)

Bk1--5 to 23 centimeters, (2 to 9 inches); pale brown (10YR 6/3) very gravelly loam, brown (10YR 4/3) moist; moderate coarse subangular blocky structure; moderately hard, very friable, slightly sticky and slightly plastic; few fine to coarse roots and common very fine roots; few fine to coarse tubular and common very fine interstitial pores; 60 percent continuous prominent white (10YR 8/1), calcium carbonate coats on bottom surfaces of rock fragments; 2 percent fine prominent platy strongly cemented white (10YR 8/1), calcium carbonate nodules with sharp boundaries on bottom of rock fragments; 10 percent fine gravel, 30 percent medium to coarse gravel, 3 percent cobbles, 1 percent stones; violently effervescent; moderately alkaline (pH 8.4); clear wavy boundary. (12 to 25 centimeters thick)

Bk2--23 to 79 centimeters, (9 to 31 inches); pale brown (10YR 6/3) extremely gravelly sandy loam, brown (10YR 4/3) moist; massive; soft, very friable, slightly sticky and nonplastic; few fine and medium roots and many very fine roots; few fine tubular and common very fine interstitial pores; 60 percent continuous prominent white (10YR 8/1), calcium carbonate coats on bottom surfaces of rock fragments; 2 percent fine prominent platy strongly cemented white (10YR 8/1), calcium carbonate nodules with sharp boundaries on bottom of rock fragments and 3 percent coarse prominent irregular white (10YR 8/1), calcium carbonate masses with clear boundaries in matrix surrounding concentrations; 10 percent fine gravel, 55 percent medium and coarse gravel, 3 percent cobbles, 2 percent stones; violently effervescent; strongly alkaline (pH 8.6); abrupt wavy boundary. (40 to 60 centimeters thick)

Bk3--79 to 152 centimeters, (31 to 60 inches); pale brown (10YR 6/3) stratified extremely gravelly sandy loam to extremely gravelly loamy coarse sand, averages extremely gravelly sandy loam, brown (10YR 4/3) moist; massive; moderately hard, very friable, nonsticky and nonplastic; few fine roots and common very fine roots; few fine interstitial and common very fine interstitial pores; 60 percent continuous prominent white (10YR 8/1), calcium carbonate coats on bottom surfaces of rock fragments; 5 percent medium prominent platy strongly cemented white (10YR 8/1), calcium carbonate nodules with sharp boundaries on bottom of rock fragments and 15 percent coarse prominent platy weakly cemented very pale brown (10YR 8/2), calcium carbonate nodules with clear boundaries along lamina or strata surfaces; 30 percent fine gravel, 40 percent medium and coarse gravel, 2 percent cobbles, 1 percent stones; violently effervescent; strongly alkaline (pH 8.8).

TYPE LOCATION: Clark County, Nevada; about 24 kilometers north and 3 kilometers east of Corn Creek Station, Nevada on the Westside of the Sheep Mountain Range; approximately 2.5 kilometers east of Alamo Road; 155 meters north and 772 meters east of the southwest corner of sec. 10, T. 15 S., R. 59 E.; U.S.G.S. White Sage Flat, NV 7.5 minute topographic quadrangle; 36 degrees, 39 minutes, 17.7 seconds north latitude and 115 degrees, 19 minutes, 16.4 seconds west longitude; UTM 11S, 650050 easting, 4057906 northing; DTM: NAD83.

RANGE IN CHARACTERISTICS:

Soil moisture: Usually dry, moist in some part for short periods during winter and early spring. The soils have a typic-aridic soil moisture regime.

Soil temperature: 15 to 18 degrees C.

Depth to calcic horizon: 18 to 50 centimeters.

Depth to petronodic feature: 50 to 100 centimeters.

Control section
Clay content: averages 7 to 12 percent, ranges from 5 to 14 percent.
Rock fragments: 60 to 80 percent, mainly gravel.

A horizon:
Value: 4 or 5 moist.
Chroma: 3 or 4, dry or moist.
Calcium carbonate equivalence of the fine earth: 20 to 40 percent.

Bk1 or Bkq1 horizon:
Value: 6 or 7 dry, 4 or 5 moist.
Chroma: 3 or 4, dry or moist.
Texture: loam or fine sandy loam.
Rock fragments: 35 to 60 percent, mainly gravel.
Calcium carbonate equivalence of the fine earth: 30 to 50 percent.
Sodium Adsorption Ratio: 0 to 5 ds/m.
Electrical conductivity: 0 to 4.

Bk2 or Bkq2 horizon:
Value: 6 or 7 dry, 4 or 5 moist.
Chroma: 2 or 3 dry, 3 or 4 moist.
Texture: averages sandy loam, individual strata ranges from sandy loam to loamy coarse sand.
Clay content: ranges from 5 to 14 percent.
Rock fragments: 60 to 80 percent, dominently gravel.
Reaction: strongly alkaline or very strongly alkaline.
Calcium carbonate equivalence of the fine earth: 40 to 60 percent.
Sodium Adsorption Ratio: 13 to 45 ds/m.
Electrical conductivity: 4 to 16.
Other features: 20 to 50 percent very weakly to moderately cemented calcium carbonate nodules and/or concretions in the lower part of the profile.

COMPETING SERIES: These are the Destazo (CA), Driftfence (NM) and Pahrump (NV) series. Destazo soils have a clay content of 18 to 35 percent in the control section. Pahrump soils have a clay content of 18 to 27 percent in the control section. Destazo and Pahrump soils do not have limestone fragments. Pahrump soils also have a mean annual soil temperature of 18 to 21 degrees C. Driftfence soils are moist for more than 20 days cumulative between July and September and have a mean annual soil temperature of 18 to 20 degrees C. (64 to 68 degrees F.).

GEOGRAPHIC SETTING: Alamoroad soils are on fan remnants. Slope ranges from 4 to 15 percent. These soils formed in alluvium derived from limestone. Elevations are 1400 to 1750 meters. The climate is arid with hot, dry summers and warm, moist winters. The mean annual precipitation is 127 to 178 millimeters; mean annual air temperature is 13 to 17 degrees C., and the frost-free season is 170 to 250 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are Threelakes and Weiser soils. Threelakes soils do not have a calcic horizon or petronodic features and are located on fan aprons. Weiser soils do not have petronodic features and are located on fan remnants.

DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY: Well drained, low to high runoff, moderately high saturated hydraulic conductivity.

USE AND VEGETATION: These soils are used for rangeland and wildlife habitat. The present vegetation is mainly shadscale, ephedra, Joshua tree, threeawn and fluff grass.

DISTRIBUTION AND EXTENT: Mojave Desert of southern Nevada, U.S.A.; MLRA 30. These soils are not extensive.

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

SERIES ESTABLISHED: Clark County, Desert National Wildlife Refuge Soil Survey, Part of Energy and Defense Area, Nevada, 2008. The name is coined from Alamo Road located in the western part of the Desert National Wildlife Refuge.

REMARKS: Diagnostic horizons and features recognized in this pedon are:

Ochric epipedon - 0 to 18 centimeters (0 to 7 inches). (A and part of the Bk1 horizons)
Calcic horizon - 23 to 152 centimeters (9 to 60 inches). (Bk2 and Bk3 horizons)
Petronodic feature - 79 to 152 centimeters (31 to 60 inches). (Bk3 horizon)
Particle-size control section - 25 to 100 centimeters (10 to 40 inches). (Part of the Bk2 and Bk3 horizons)

Responsibility for this series was transferred from Davis to Phoenix 4/2015. The last revision to the series was 6/2011. ET

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National Cooperative Soil Survey
U.S.A.