LOCATION MASK CA
Established Series
Rev. JCR/LJL/ET
11/2015
MASK SERIES
The Mask series consists of very deep, somewhat excessively drained soils that formed in mixed alluvium. Mask soils are on sideslopes of fan remnants and have slopes of 8 to 30 percent. The mean annual precipitation is about 4 inches and the mean annual air temperature is about 72 degrees F.
TAXONOMIC CLASS: Sandy-skeletal, mixed, hyperthermic Durinodic Haplocalcids
TYPICAL PEDON: Mask extremely gravelly fine sandy loam, 8 to 30 percent slopes at an elevation of 1,120 feet. (Colors are for dry soil unless otherwise noted). The surface is covered by approximately 70 percent gravel, 10 percent cobbles and 5 percent stones.
A--0 to 2 inches; light yellowish brown (10YR 6/4) extremely gravelly fine sandy loam, brown (10YR 4/3) moist; moderate thin platy structure; slightly hard, very friable, slightly sticky and slightly plastic; common very fine roots; common very fine vesicular pores; electrical conductivity of 1 dS/m; sodium adsorption ratio of 2; 60 percent gravel, 5 percent cobbles and 2 percent stones; strongly effervescent (5 percent calcium carbonate equivalence); strongly alkaline (pH 9.0); clear smooth boundary. (1 to 3 inches thick).
Bk--2 to 5 inches; light brown (7.5YR 6/4) extremely gravelly coarse sandy loam, brown (7.5YR 5/3) moist; medium subangular blocky structure; soft, very friable, slightly sticky and slightly plastic; common very fine and few fine roots; common very fine and few fine tubular pores; 3 percent very fine carbonate threads; electrical conductivity of 1 dS/m; sodium adsorption ratio of 4; 60 percent gravel, 4 percent cobbles and 1 percent stones; strongly effervescent (5 percent calcium carbonate equivalence); strongly alkaline (pH 9.0); clear wavy boundary. (0 to 4 inches thick).
Btk--5 to 11 inches; very pale brown (10YR 7/4) extremely gravelly coarse sandy loam, brown (10YR 5/3) moist; moderate fine subangular blocky structure; moderately hard, very friable, slightly sticky and nonplastic; common very fine roots and few fine roots; common very fine and few fine tubular pores; 10 percent discontinuous clay films on sand grains; very few thin carbonate coats on lower surfaces of rock fragments; 2 percent fine, irregular, very pale brown (10YR 8/2) soft masses of carbonate; electrical conductivity of 1 dS/m; sodium adsorption ratio of 4; 65 percent gravel, 4 percent cobbles and 1 percent stones; slightly effervescent (5 percent calcium carbonate equivalence); very strongly alkaline (pH 9.3); clear smooth boundary. (3 to 8 inches thick.)
Bkq--11 to 33 inches; very pale brown (10YR 8/4) very gravelly loamy coarse sand, brown (10YR 5/3) moist; massive; slightly hard and hard, friable and firm, nonsticky, and nonplastic; very few thin carbonate coats on lower surfaces of rock fragments; 25 percent coarse and very coarse irregular brownish yellow (10YR 6/6) hard durinodes; 3 percent coarse platelike, brownish yellow (10YR 6/6) rigid silica laminae; 10 percent coarse and very coarse, irregular, very pale brown (10YR 8/2) bands and pockets of disseminated carbonates; electrical conductivity of 1 dS/m; sodium adsorption ratio of 4; 45 percent gravel, 4 percent cobbles and 1 percent stones; violently effervescent (15 percent calcium carbonate equivalence); very strongly alkaline (pH 9.5); clear irregular boundary. (20 to 24 inches thick)
Bkqn--33 to 60 inches; very pale brown (10YR 7/4) very gravelly loamy coarse sand, yellowish brown (10YR 5/4) moist; massive; hard, firm, nonsticky and nonplastic; very few thin carbonate coats on lower surfaces of rock fragments; 4 percent fine irregular very pale brown (10YR 8/2) soft masses of carbonate and 7 percent coarse and very coarse irregular very pale brown (10YR 8/2) bands and pockets of disseminated carbonates; 15 percent coarse and very coarse, rounded, brownish yellow (10YR 6/6) hard durinodes; 2 percent coarse platelike brownish yellow (10YR 6/6) rigid silica laminae; electrical conductivity of 2 dS/m; sodium adsorption ratio of 23; 55 percent gravel, 4 percent cobbles and 1 percent stones; strongly effervescent (10 percent calcium carbonate equivalence); very strongly alkaline (pH 9.5).
TYPE LOCATION: San Bernardino County, California; about 12 miles southwest of Amboy, CA, about 700 feet east and 1,200 feet south of the northwest corner of section 18, township 4 north., range 10 east, 34 degrees 26 minutes 18.1 seconds north latitude and 115 degrees 52 minutes 32.5 seconds west longitude; Lead Mountain quadrangle; UTM 11S, 0603357e 3811171n; 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: 72 to 77 degrees F.
Depth to durinodic horizon: 4 to 16 inches.
Depth to calcic horizon: 4 to 16 inches.
Control section -
Rock fragments: 35 to 65 percent.
A horizon
Value: 6 or 7 dry and 4 through 6 moist.
Chroma: 3 or 4 dry or moist.
Clay content: 8 to 14 percent.
Rock fragments: 55 to 80 percent.
Calcium carbonate equivalence: 1 to 8 percent.
Electrical conductivity: 0 to 4 dS/m.
Sodium adsorption ratio: 1 to 4.
Effervescence: slightly or strongly effervescent.
Reaction: strongly or very strongly alkaline.
Bk and Btk horizons
Value: 6 through 8 dry, 4 through 6 moist.
Chroma: 2 through 4 dry, 3 through 5 moist.
Clay content: 8 to 14 percent.
Rock fragments: 55 to 75 percent, mostly gravel.
Electrical conductivity: 0 to 4 dS/m.
Sodium adsorption ratio: 1 to 4.
Calcium carbonate equivalence: 2 to 8 percent.
Effervescence: slightly or strongly effervescent
Reaction: Strongly or very strongly alkaline.
Bkq horizon
Value: 7 or 8 dry, 5 through 7 moist.
Chroma: 2 through 4 dry or moist.
Clay content: 4 to 8 percent.
Rock fragments: 35 to 65 percent, mostly gravel.
Secondary carbonates: 10 to 20 percent, typically as nodules and soft masses.
Electrical conductivity: 0 to 4 dS/m.
Sodium adsorption ratio: 3 to 12.
Calcium carbonate equivalent: 10 to 20 percent.
Reaction: strongly or very strongly alkaline.
Other features: 20 to 35 percent durinodes; 0 to 5 percent silica laminae.
Bkqn horizon
Value: 7 or 8 dry, 5 through 7 moist.
Chroma: 2 through 4 dry or moist.
Clay content: 4 to 8 percent.
Rock fragments: 35 to 65 percent, mostly gravel.
Secondary carbonates: 10 to 20 percent, typically as nodules and soft masses.
Electrical conductivity: 0 to 4 dS/m.
Sodium adsorption ratio: 13 to 25.
Calcium carbonate equivalent: 5 to 15 percent.
Reaction: strongly or very strongly alkaline.
Other features: 20 to 35 percent durinodes; 0 to 5 percent silica laminae.
COMPETING SERIES: There are no competing series at this time.
GEOGRAPHIC SETTING: Mask soils are on sideslopes of fan remnants. Slopes are 8 to 30 percent. These soils formed in mixed alluvium. Elevations are 1,000 to 1,700 feet. The climate is arid with hot, dry summers and warm, moist winters. The mean annual precipitation is 2 to 6 inches; the mean annual air temperature is 69 to 74 degrees F.and the frost-free season is 300 to 360 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the
Carrizo and
Clegorpass soils. Clegorpass soils have argillic horizons. Carrizo soils do not have calcic horizons.
DRAINAGE AND PERMEABILITY: Somewhat excessively drained; low or medium runoff; moderately rapid over rapid permeability.
USE AND VEGETATION: Military exercises and wildlife habitat. The present vegetation is mainly creosotebush and white bursage.
DISTRIBUTION AND EXTENT: Mojave Desert of southeastern California. MLRA 30. These soils are not extensive.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: PHOENIX, ARIZONA
SERIES ESTABLISHED: San Bernardino County, Marine Corps Air Ground Combat Center Soil Survey Area, California, 2000. The name is coined.
REMARKS: Diagnostic horizons and features in this pedon are:
1. Ochric epipedon--0 to 5 inches (A and Bk horizons).
2. Calcic horizon--11 to 33 inches (Bkq horizon).
3. Durinodic layer--11 to 33 (Bkq horizon).
4. Particle-size control section--10 to 40 inches (Part of the Bk, the Bkq and part of the Bkqn horizons).
Responsibility for this series was transferred from Davis to Phoenix 11/2015. The last revision to the series was 6/2000. ET
National Cooperative Soil Survey
U.S.A.