LOCATION LANGWELL CA
Established Series
Rev: CAH/PBF/ET
09/2015
LANGWELL SERIES
The Langwell series consists of very shallow and shallow, somewhat excessively drained soils formed in granitic or metamorphic residuum. The Langwell soils are on mountains, hills, and pediments. Slope ranges from 2 to 50 percent. The mean annual precipitation is about 5 inches and the mean annual temperature is about 66 degrees F.
TAXONOMIC CLASS: Loamy, mixed, superactive, calcareous, thermic Lithic Torriorthents
TYPICAL PEDON: On Dalvord-Rock outcrop-Langwell complex, 15 to 50 percent slopes at an elevation of 2,680 feet. (Colors are for dry soil unless otherwise noted.) The soil surface is covered with 30 percent gravel, 20 percent cobbles, and 5 percent stones.
A -- 0 to 1 inch; pale brown (10YR 6/3) gravelly loam, dark grayish brown (10YR 4/2) moist; weak fine subangular blocky structure; soft, friable, slightly sticky and slightly plastic; few very fine and fine roots throughout; strongly effervescent; 25 percent gravel and 5 percent cobbles; slightly alkaline (pH 7.6); abrupt wavy boundary. (1 to 4 inches thick)
C -- 1 to 6 inches; light yellowish brown (10YR 6/4) gravelly loam, brown (10YR 4/3) moist; massive; soft, friable, slightly sticky and slightly plastic; few very fine and fine roots throughout; strongly effervescent; 20 percent gravel and 5 percent cobbles; slightly alkaline (pH 7.8); clear irregular boundary. (3 to 10 inches thick)
R -- 6 inches; unweathered and fractured granitic bedrock with pockets of weathered bedrock material of moderate to high excavation difficulty.
TYPE LOCATION: San Bernardino County, California; 900 feet east and 1,000 feet north of the southwest corner of sec. 21, T. 14 N., R. 3 E., 35 degrees, 17 minutes, and 20 seconds north latitude, and 116 degrees, 40 minutes, and 25.5 seconds west longitude; Fort Irwin quadrangle. UTM 11S, 0529650e 3905930n.
RANGE IN CHARACTERISTICS:
Soil moisture control section: 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: 63 to 72 degrees F.
Organic matter: 0 to 0.5 percent
Depth to bedrock: 4 to 14 inches
Surface rock fragments: 10 to 65 percent gravel, 0 to 40 percent cobbles, and 0 to 15 percent stones.
Control section -
Clay content: 8 to 20 percent
Texture of the fine earth: sandy loam or loam
Rock fragments: 10 to 30 percent
A Horizon
Hue: 10YR or 2.5Y
Value: 5 to 7 dry and 4 or 5 moist
Chroma: 2 to 4 dry or moist
Rock fragments: 10 to 60 percent gravel, 0 to 30 percent cobbles, and 0 to 5 percent stones; range is from 35 to 60 percent
Reaction: slightly or moderately alkaline
C Horizon
Hue: 10YR or 2.5Y
Value: 5 to 7 dry and 4 or 5 moist
Chroma: 2 to 4 dry or moist
Rock fragments: 10 to 30 percent gravel and 0 to 10 percent cobbles; range is 10 to 30 percent
Reaction: slightly or moderately alkaline
Some pedons have a thin weak Bw horizon with similar characteristics of the A horizon.
R Horizon
Unweathered, slightly to highly fractured granitic bedrock, with pockets of slightly to moderately weathered bedrock material of moderate to extremely high excavation difficulty.
COMPETING SERIES: These are the
Delgado,
Splanod,
Tidwell, and
Trigger series. Delgado and Splanod soils form from sandstones and shales. In addition, Delgado soils are deeper to bedrock. Splanod soils have hues of 2.5YR and 5YR. Tidwell and Trigger soils are derived from sedimentary rocks. In addition, Tidwell soils have redder hues and Trigger soils have a MAST of 61 to 64 and the moisture control section that is dry from
May through October.
GEOGRAPHIC SETTING: The Langwell soils are on mountains, hills, and pediments. Slope ranges from 2 to 50 percent. The soils formed in material from granitic sources. Elevations are 1,900 to 3,800 feet. The climate is arid, with hot, dry summers and cool winters. Most precipitation comes in the winter but in some areas it is sporadic. The mean annual precipitation is 3 to 7 inches. The mean annual temperature is 61 to 70 degrees F. Mean July temperature is about 78 degrees F., and mean January temperature is about 42 degrees F. The frost-free season is 240 to 340 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the
Artillery,
Cajon,
Dalvord, and
Twobitter soils. Artillery soils are found on lower landscape positions on the same landform. They have a loamy-skeletal particle-size control section and an argillic horizon. Cajon soils are on adjacent alluvial fans and inset fans. They have a sandy particle-size control section and are deep or very deep. Dalvord soils are found on similar positions and have a loamy-skeletal particle-size control section. Twobitter soils are on fan remnants with a patina surface. They are deep, have a loamy-skeletal particle-size control section, and an argillic horizon.
DRAINAGE AND PERMEABILITY: Somewhat excessively drained; very low to high runoff; moderate to moderately rapid permeability.
USE AND VEGETATION: Langwell soils are used for military exercises and wildlife habitat. The present vegetation is creosotebush, white bursage, range ratany, desert needlegrass and Mojave aster.
DISTRIBUTION AND EXTENT: Mojave Desert of southeastern California. MLRA 30. The series is of moderate extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: PHOENIX, ARIZONA
SERIES ESTABLISHED: San Bernardino County, California, Fort Irwin Soil Survey Area, 2000. The name is from Langford Well Lake, a playa.
REMARKS: Diagnostic horizons and features recognized in the profile are:
1. ochric epipedon -- 0 to 1 inch. (A horizon)
2. lithic contact -- 7 inches. (R)
3. Particle-size control section -- 0 to 6 inches (A and C
horizons)
Responsibility for this series was transferred from Davis to Phoenix 9/2015. The last revision to the series was 5/2007. ET
National Cooperative Soil Survey
U.S.A.