LOCATION LAVABED CA
Established Series
Rev: JCR/LJL/ET
09/2015
LAVABED SERIES
The Lavabed series consists of very shallow to paralithic contact, well drained soils that formed in residuum and colluvium from granite. Lavabed soils are on mountains and have slopes of to 8 to 50 percent. The mean annual precipitation is about 6 inches and the mean annual air temperature is about 60 degrees F.
TAXONOMIC CLASS: Loamy-skeletal, mixed, superactive, calcareous, thermic, shallow Typic Torriorthents
TYPICAL PEDON: Lavabed-Dalvord association, 8 to 50 percent slopes, at an elevation of 4,000 feet. (Colors are for dry soil unless otherwise noted.) The surface is covered by approximately 75 percent gravel, 3 percent cobbles and trace of stones.
A--0 to 1 inch; yellowish brown (10YR 5/4) very gravelly loamy coarse sand, dark brown (10YR 3/3) moist; weak medium platy structure; soft, very friable, nonsticky and nonplastic; common very fine roots; common very fine and few fine interstitial pores; 45 percent gravel, 3 percent cobbles and a trace of stones; strongly effervescent; moderately alkaline (pH 8.0); abrupt smooth boundary. (1 to 3 inches thick).
C--1 to 5 inches; light yellowish brown (10YR 6/4) very gravelly sandy loam, dark yellowish brown (10YR 4/4) moist; moderate medium subangular blocky structure; soft, very friable, slightly sticky and nonplastic; common very fine and few fine and medium roots; few very fine and fine tubular pores; 55 percent gravel, 3 percent cobbles and trace of stones; violently effervescent; moderately alkaline (pH 8.2); abrupt wavy boundary. (3 to 8 inches thick).
Cr--5 to 14 inches; moderately hard fractured bedrock; few very fine, fine and medium roots in fractures; clear wavy boundary. (4 to 16 inches thick).
R--14 inches; hard granitic bedrock.
TYPE LOCATION: San Bernardino County, California; about 18.5 miles west by southwest of Ludlow, California; 250 feet south and 2,400 feet west of the northeast corner of section 30, T. 7 N., R. 5 E.; 34 degrees, 40 minutes, 33.0 seconds north latitude and 116 degrees, 29 minutes, 39.4 seconds west longitude; Sunshine Peak quadrangle; UTM 11S, 0546330e 3837015n; NAS-C.
RANGE IN CHARACTERISTICS:
Soil moisture - usually dry, moist in some part for short periods during winter and early spring and for 10 to 20 days cumulative between July and October following convection storms. The soils have a Typic-Aridic moisture regime.
Soil temperature: 59 to 65 degrees F.
Depth to paralithic contact: 4 to 10 inches.
Depth to lithic contact: 8 to 20 inches.
Organic matter: 0 to 0.5 percent.
Control section -
Rock fragments: 45 to 80 percent mainly gravel.
Clay content: 4 to 12 percent.
A horizon
Value: 5 or 6 dry, 3 to 5 moist.
Chroma: 2 to 4 dry.
Texture of the fine earth: Loamy coarse sand, loamy sand, or sandy loam.
Consistence: Soft or slightly hard.
Effervescence: Strongly or violently effervescent.
Calcium carbonate equivalent: 1 to 5 percent.
C horizon
Value: 4 or 5 moist.
Chroma: 2 to 4 dry, 3 or 4 moist.
Texture of the fine earth: Coarse sandy loam or sandy loam.
Structure: Subangular blocky or massive.
Effervescence: Strongly or violently effervescent.
Calcium carbonate equivalent: 1 to 5 percent.
COMPETING SERIES: These are the
Dixaleta (AZ+NV),
Seanna T(NV),
Shankba (NV) and
Xyzoic series. Dixaleta soils have mean annual soil temperature of 67 to 71 degrees F and depth to lithic contact is 20 to 60 inches. Seanna soils have mean annual soil temperature 66 to 71 degrees F and depth to lithic contact is 20 to 40 inches. Shankba soils are 14 to 20 inches deep to the paralithic contact and 20 to 26 inches deep to the lithic contact. Xyzoic soils have hues of 2.5Y and hard bedrock at 20 to 30 inches.
GEOGRAPHIC SETTING: Lavabed soils are on mountains. Slopes are 8 to 50 percent. These soils formed in residuum and colluvium from granite. Elevations are 3,200 to 4,400 feet. The climate is arid with hot, dry summers and warm, moist winters. The mean annual precipitation is 4 to 7 inches; mean annual air temperature is 57 to 63 degrees F., and the frost-free season is 180 to 240 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the
Dalvord soils. Dalvord soils do not have a paralithic contact.
DRAINAGE AND PERMEABILITY: Well drained; very high runoff; moderately rapid permeability over impermeable bedrock.
USE AND VEGETATION: Lavabed soils are used for military exercises and wildlife habitat. The present vegetation is mainly blackbrush, creosotebush, spiny menodora and Nevada ephedra.
DISTRIBUTION AND EXTENT: Mojave desert of southeastern California, U.S.A.; MLRA 30. These soils are of small extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: PHOENIX, ARIZONA
SERIES ESTABLISHED: San Bernardino County, California, Marine Corps Air/Ground Combat Center Soil Survey Area, 2000. The name is from the Lavabed Mountains.
REMARKS: Diagnostic horizons and features recognized in the profile are:
1. Ochric epipedon -- 0 to 5 inches (A and C horizons).
2. Paralithic contact -- 5 to 14 inches (Cr horizon).
3. Particle-size control section -- 0 to 5 inches (A and C horizons).
Responsibility for this series was transferred from Davis to Phoenix 9/2015. The last revision to the series was 6/2000. ET
National Cooperative Soil Survey
U.S.A.