LOCATION MOUNTMUMMY NV

Established Series
Rev: LJL/ET/TM
11/2015

MOUNTMUMMY SERIES

The Mountmummy series consists of moderately deep, well drained soils that formed in residuum and colluvium from limestone and dolomite. Mountmummy soils are on upper back slopes of mountains. Slope ranges from 30 to 75 percent. The mean annual precipitation is about 18 inches and the mean annual air temperature is about 42 degrees F.

TAXONOMIC CLASS: Loamy-skeletal, carbonatic, frigid Pachic Calciustolls

TYPICAL PEDON: Mountmummy extremely gravelly loam, forest and wildlife habitat. (Colors are for dry soil unless otherwise noted.) The soil surface is covered by approximately 75 percent gravel, 10 percent cobbles and 2 percent stones.

A--0 to 2 inches; dark yellowish brown (10YR 4/4) extremely gravelly loam, dark brown (10YR 3/3) moist; moderate medium subangular blocky structure; soft, very friable, slightly sticky and nonplastic; few very fine roots throughout; common fine tubular and many very fine tubular pores; 60 percent pebbles, 5 percent cobbles and 1 percent stones; very slightly effervescence (35 percent calcium carbonate equivalent in the fine earth fraction); slightly alkaline (pH 7.8); clear smooth boundary. (1 to 3 inches thick)

Bk1--2 to 12 inches; yellowish brown (10YR 5/4) extremely gravelly loam, dark brown (10YR 3/3) moist; moderate medium subangular blocky structure; slightly hard, very friable, slightly sticky and nonplastic; common very fine through very coarse roots throughout; common very fine and fine tubular pores; 80 percent prominent white (10YR 8/1) calcium carbonate coats on bottom surfaces of rock fragments; 55 percent pebbles, 10 percent cobbles and 1 percent stones; slightly effervescence (50 percent calcium carbonate equivalent in the fine earth fraction); moderately alkaline (pH 7.9); abrupt smooth boundary. (4 to 13 inches thick)

Bk2--12 to 24 inches; light yellowish brown (10YR 6/4) extremely cobbly fine sandy loam, brown (10YR 4/3) moist; massive; moderately hard, very friable, slightly sticky and nonplastic; few very fine and fine roots and common medium and coarse roots throughout; many very fine pores; 50 percent 2 to 30 millimeter calcium carbonate masses, distinct, very pale brown (10YR 7/3) dry, brown (10YR 5/3) moist, irregular, in matrix around concentrations, moderately hard, diffuse; 90 percent fine prominent very pale brown (10YR 8/2) calcium carbonate pendants on bottom of rock fragments; 40 percent pebbles, 40 percent cobbles and 5 percent stones; violently effervescence (75 percent calcium carbonate equivalent in the fine earth fraction); moderately alkaline (pH 7.9); abrupt irregular boundary. (7 to 27 inches thick)

R--24 inches; hard limestone bedrock.

TYPE LOCATION: Clark County, Nevada; about 8 miles north and 27 miles west of Las Vegas, Nevada; approximately 3.7 miles east and 1.8 mile north of Charleston Peak or 0.7 mile east of Mummy Spring located in the Spring Mountians; tentatively sectionalized area 1,810 feet north and 2,500 feet east of the southwest corner of section 18, T. 19 S., R. 57 E.; USGS Charleston Peak, NV 7.5 minute quadrangle; 36 degrees, 17 minutes, 46.4 seconds north latitude and 115 degrees, 37 minutes, 36.9 seconds west longitude; UTM 11, 623291e 4017680n; NAD83.

RANGE IN CHARACTERISTICS:

Soil moisture - usually dry, moist in late winter and early spring and intermittently moist in the upper part following summer convection storms; ustic soil moisture regime bordering on aridic.

Soil temperature: 41 to 46 degrees F.

Depth to base of mollic epipedon: 20 to 40 inches

Depth to calcic horizon: 10 to 20 inches

Depth to lithic contact: 20 to 40 inches.

Control section - Rock fragments: 60 to 90 percent.
Clay content: 8 to 18 percent.

A horizon - Calcium carbonate equivalent in the fine earth fraction: 20 to 40 percent.
Organic matter: 4 to 8 percent.

Bk horizons - Value: 5 or 6 dry, and 3 or 4 moist.
Structure: Subangular blocky or massive.
Calcium carbonate equivalent in the fine earth fraction: 40 to 80 percent.
Organic matter: 2 to 5 percent.
Reaction: Slightly alkaline to moderately alkaline.
Other: Calcium carbonate concentrations range from prominent coats and fine pendants on the bottom of rock fragments to moderately hard calcium carbonate masses suspended in the fine earth matrix.

COMPETING SERIES: These are the Kitgram (NV) and Maryjane (NV) series. Kitgram soils have a calcic horizon at 1 to 3 inches. Maryjane soils do not have bedrock within 60 inches.

GEOGRAPHIC SETTING: Mountmummy soils are on upper back slopes of mountains. Slope ranges from 30 to 75 percent. These soils formed in residuum and colluvium from limestone and dolomite. Elevations are 8,500 to 11,000 feet. The climate is sub-humid continental, cool, with moist winters and common summer convection storms. The mean annual precipitation is 16 to 20 inches; mean annual air temperature is 40 to 45 degrees F., and the frost-free season is 50 to 90 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are Maryjane and Thesisters soils. Maryjane soils do not have bedrock. Thesisters soils are very shallow and shallow to bedrock.

DRAINAGE AND PERMEABILITY: Well drained; high runoff; moderate permeability.

USE AND VEGETATION: These soils are used for forest and wildlife habitat. The present vegetation is mainly Rocky Mountain bristlecone pine.

DISTRIBUTION AND EXTENT: Mojave Desert of southern Nevada; MLRA 30. These soils are moderately extensive.

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

SERIES ESTABLISHED: Clark County Area, Nevada, 2006. Proposed in Clark County, Nevada; Clark County Soil Survey, 2004. The name is coined from Mummy Mountain located in the Spring Mountains.

REMARKS: Diagnostic horizons and features recognized in the profile are:
Mollic epipedon - 0 to 24 inches (A, Bk1 and Bk2 horizons).
Calcic horizon - 12 to 24 inches (Bk2 horizon)
Lithic contact - 24 inches (R layer).
Particle-size control section - 10 to 24 inches (Part of the Bk1 and Bk2 horizons).

Additional data: Sampled on October 5, 2004, by NRCS Nevada staff, samples sent to NSSL, Lincoln, NE. Pedon ID is SO4NV-003-005.

Responsibility for this series was transferred from Davis to Phoenix 11/2015. The last revision to the series was 7/2006. ET

National Cooperative Soil Survey
U.S.A.