LOCATION LAVATANK                CA

Established Series
LJL/MEB/NS
02/2025

LAVATANK SERIES

The Lavatank series consists of very deep, well drained soils that formed in eolian deposits in the upper part of residuum weathered from aa lava or cinders derived from volcanic rock. The Lavatank soils are on cinder cones and "aa" lava flows. Slopes range from 8 to 75 percent. The mean annual precipitation is about 138 mm, and the mean annual temperature is about 18 degrees C.

TAXONOMIC CLASS: Loamy-skeletal over cindery, mixed, superactive, calcareous, thermic Typic Torriorthents

TYPICAL PEDON: Lavatank very gravelly sandy loam, on a south facing, 60 percent slope under rangeland at an elevation of 1009 meters. (Colors are for dry soils unless otherwise noted. 5/23/2019 actual site observation date.) The soil surface is covered by approximately 5 percent fine gravel, 75 percent medium and coarse gravel, 15 percent cobbles, 1 percent stones.

A--0 to 5 cm (0 to 2 inches); pale brown (10YR 6/3) very gravelly sandy loam, brown (10YR 4/3), moist; moderate medium subangular blocky structure; moderately hard, very friable, nonsticky and slightly plastic; common fine irregular and common very fine irregular pores; 5 percent fine gravel, 40 percent medium and coarse gravel, 7 percent cobbles, 1 percent stones; slightly alkaline (pH 7.8); abrupt smooth boundary. (5 to 13 cm thick)

Bt--5 to 12 cm (2 to 5 inches); pale brown (10YR 6/3) very gravelly loam, dark yellowish brown (10YR 4/4), moist; moderate coarse subangular blocky structure; hard, very friable, slightly sticky and slightly plastic; common fine irregular and common very fine irregular pores; 5 percent prominent brown (7.5YR 5/4), dry, clay films on rock fragments and 20 percent prominent brown (7.5YR 5/4), dry, clay films on all faces of peds; 5 percent fine gravel, 30 percent medium and coarse gravel, 3 percent cobbles, 1 percent stones; very slight effervescence; moderately alkaline (pH 8.2); clear smooth boundary. (0 to7 cm thick)

Bk--12 to 62 cm (5 to 24 inches); pale brown (10YR 6/3) extremely gravelly sandy loam, dark yellowish brown (10YR 4/4), moist; massive; soft, very friable, nonsticky and slightly plastic; common fine irregular and common very fine irregular pores; 60 percent prominent pale orange yellow (10YR 9/2), dry, carbonate coats on bottom surfaces of rock fragments; 1 percent fine faint spherical noncoherent cemented pale orange yellow (10YR 9/2), dry, carbonate masses with sharp boundaries on bottom of rock fragments; 10 percent fine gravel, 45 percent medium and coarse gravel, 10 percent cobbles, 5 percent stones; violent effervescence; strongly alkaline (pH 8.8); gradual wavy boundary. (25 to 60 cm thick)

Ck--62 to 120 cm (24 to 47 inches); very dark gray (10YR 3/1) gravel, black (10YR 2/1), moist; massive; soft, very friable, nonsticky and nonplastic; common medium interstitial and common coarse interstitial pores; 60 percent prominent pale orange yellow (10YR 9/2), dry, carbonate coats on bottom surfaces of rock fragments; 1 percent fine faint spherical noncoherent cemented pale orange yellow (10YR 9/2), dry, carbonate masses with sharp boundaries on bottom of rock fragments; 15 percent fine gravel, 60 percent medium and coarse gravel, 10 percent cobbles, 5 percent stones; violent effervescence; moderately alkaline (pH 8.0); Less than 10 percent black very coarse sand in voids.

TYPE LOCATION: San Bernardino County, California; located in the Cinder Cone Lava Beds 15 miles northwest of Kelso, CA; approximately 1100 feet east and 1800 feet north of the southwest corner of section 14, T. 13 N., R. 11 E., San Bernardino Baseline and Meridian; USGS Indian Spring, California 7.5 minute topographic quadrangle; 35 degrees, 12 minutes, 32.76 seconds north latitude and 115 degrees, 47 minutes, 13.63 seconds west longitude; UTM zone 11 610398e, 3896906n, WGS84.

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 September following summer convection storms; typic aridic moisture regime.

Soil temperature: 18 to 22 degrees C (64 to 72 degrees F).
Depth to cindery material: 40 to 70 cm.

Control section
Clay content: 5 to 12 percent in the upperpart and 0 to 5 percent in the lower part.

A horizon
Value: 3 or 4 moist.
Chroma: 3 or 4.
Texture: fine sandy loam or sandy loam.
Clay content: 5 to 12
Rock fragments: 35 to 85 percent, mainly gravel with 3 to 20 percent cobbles and stones.
Effervescence: noneffervescent or very slightly effervescent.
Reaction: slightly alkaline or moderately alkaline.

Bt horizon (when present)
Clay content: 10 to 16 percent.
Rock fragments: 35 to 60 percent, mainly gravel.

Bk horizon
Chroma: 3 or 4 moist.
Texture: fine sandy loam or sandy loam.
Clay content: 5 to 12
Rock fragments: 60 to 85 percent, mainly gravel with 8 to 25 percent cobbles and stones.
Structure: massive or subangular blocky.
Consistence: soft or slightly hard, nonplastic or slightly plastic.
Effervescence: very slightly effervescent to violently effervescent.
Reaction: moderately alkaline or strongly alkaline.

Ck horizon
Texture: coarse sand makes up less than 5 percent of the horizon.
Rock fragments: Cinders make up to 90 percent of the horizon.
Note: common fine through coarse irregular pores (or gaps) make up to 10 percent of the profile.

COMPETING SERIES: There are no competing series.

GEOGRAPHIC SETTING: The Lavatank soils are on cinder cones and "aa" lava flows. Slopes range from 8 to 75 percent. The soils formed in eolian deposits in the upper part of residuum weathered from aa lava or cinders derived from volcanic rock. Elevation ranges from 770 to 1400 meters. The mean annual precipitation is 150 to 200 mm. The mean annual air temperature is about 16 to 20 degrees C. The frost-free period is 270 to 320 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Railroad series. Railroad soils are moderately deep to bedrock and have a calcic horizon.

DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY: well drained; high runoff; moderately high saturated hydraulic conductivity.

USE AND VEGETATION: Lavatank soils are used for recreation and wildlife habitat. Native vegetation is creosote bush and Fremont dalea.

DISTRIBUTION AND EXTENT: Mojave Basin and Range of California, U.S.A.; MLRA 30. The series is of small extent.

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

SERIES PROPOSED: San Bernardino County, California, Soil Survey of Mojave National Preserve Area, California, 2022. The name is coined.

REMARKS: Diagnostic horizons and features in this pedon include:

Ochric epipedon - the zone from 0 to 18 cm. (A, Bt and part of the Bk horizons)
Particle size control section - the zone from 25 to 100 cm. (Part of the Bk and Ck horizons)

ADDITIONAL DATA: NASIS User/Pedon Site ID: 2019CA0718334.
Located on cinder cones and recent basalt flows from about 16,000 years ago.
12/22/22 Changed Cindery, mixed thermic to Loamy-skeletal over cindery, mixed, superactive, calcareous, thermic per NASIS validation check Component Taxonomic Family Particle Size.

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National Cooperative Soil Survey
U.S.A.