LOCATION BLACKMAGIC CA
Established Series
Rev: PBF/LJL/ET
04/2015
BLACKMAGIC SERIES
The Blackmagic series consists of very deep, well drained soils that formed in dominantly igneous alluvium. The Blackmagic soils are on alluvial fan remnants. Slope ranges from 2 to 4 percent. The mean annual precipitation is about 5 inches, and the mean annual temperature is about 64 degrees F.
TAXONOMIC CLASS: Fine-loamy, mixed, superactive, thermic Typic Calciargids
TYPICAL PEDON: On Blackmagic association, 2 to 4 percent slopes at an elevation of 3,540 feet. (Colors are for dry soil unless otherwise noted. When described on June 27, 1997, the soil was dry throughout.) The soil surface is covered by a trace of stones, 5 percent cobbles, and 80 percent gravel.
A -- 0 to 2 inches; pale brown (10YR 6/3) extremely gravelly silt loam, brown (10YR 4/3) moist; moderate thin platy structure; soft, very friable, nonsticky and nonplastic; many very fine and fine roots throughout; common very fine and fine interstitial, and few fine vesicular pores; noneffervescent; 65 percent gravel, 5 percent cobbles, and a trace of stones; moderately alkaline (pH 7.9); clear wavy boundary. (2 to 4 inches thick)
Bt -- 2 to 5 inches; yellowish brown (10YR 5/4) gravelly silt loam, dark yellowish brown (10YR 4/4) moist; strong medium subangular blocky structure; moderately hard, firm, nonsticky, moderately plastic; many very fine and fine roots throughout; few very fine and fine tubular pores; 15 percent faint discontinuous clay films on ped faces; very slightly effervescent; 25 percent gravel and 5 percent cobbles; moderately alkaline (pH 8.0); clear wavy boundary. (0 to 5 inches thick)
Btk1 -- 5 to 26 inches; yellowish brown (10YR 5/4) clay loam, brown (10YR 4/3) moist; strong coarse and very coarse prismatic structure; hard, firm, slightly sticky and moderately plastic; common very fine and fine roots throughout; common very fine and fine tubular pores; 35 percent faint discontinuous clay films on ped faces; 1 percent threads and fine and medium soft masses of carbonate throughout; slightly effervescent; 1 percent gravel; moderately alkaline (pH 8.3); clear wavy boundary.
Btk2 -- 26 to 37 inches; light yellowish brown (10YR 6/4) very gravelly clay loam, yellowish brown (10YR 5/4) moist; moderate fine and medium subangular blocky structure; hard, firm, slightly sticky and moderately plastic; common very fine and fine roots throughout; few very fine and fine tubular pores; 30 percent distinct discontinuous clay films on ped faces; 3 percent medium and coarse soft masses of carbonate throughout and 5 percent carbonate coats on rock fragments; violently effervescent; 35 percent gravel and 3 percent cobbles; moderately alkaline (pH 8.2); gradual wavy boundary. (Combined thickness of the Btk horizon is 20 to 35 inches)
Btky -- 37 to 45 inches; light yellowish brown (10YR 6/4) very gravelly loam, yellowish brown (10YR 5/4) moist; weak fine and medium subangular blocky structure; hard, firm, nonsticky and moderately plastic; few very fine and fine roots throughout; few very fine and fine tubular pores; 25 percent distinct discontinuous clay films throughout; 3 percent medium and coarse soft masses of carbonate throughout and 5 percent carbonate coats on rock fragments; 3 percent scattered pockets of gypsum as soft masses on sides of peds; strongly effervescent; 45 percent gravel and 7 percent cobbles; moderately alkaline (pH 8.2); clear wavy boundary. (5 to 10 inches thick)
Bkq -- 45 to 60 inches; very pale brown (10YR 7/3) extremely gravelly sandy loam, dark yellowish brown (10YR 4/4) moist; weak fine subangular blocky structure; slightly hard, very friable, nonsticky and nonplastic; few very fine and fine roots throughout; 15 percent medium and coarse soft masses of carbonate throughout and 5 percent carbonate coats on undersides of rock fragments, 15 percent strongly cemented discontinuous strata and strongly cemented and brittle durinodes; violently effervescent; 50 percent gravel and 10 percent cobbles; moderately alkaline (pH 8.2).
TYPE LOCATION: San Bernardino County, California; about 12,325 feet north of the center of section 3, T. 14 N., R. 2 E. in an unsectionalized area, 35 degrees, 22 minutes, and 09 seconds north latitude and 116 degrees, 45 minutes, and 19 seconds west longitude, East of Goldstone 7.5 minute quadrangle. (11S, 0522242e 3913817n; datum = NAS-C)
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 68 degrees F.
Organic matter: 0 to 0.5 percent
Surface rock fragments: 45 to 80 percent gravel, 5 to 30 percent cobbles and 0 to 5 percent stones.
Control section-
Clay content: 18 to 30 percent.
Rock fragments: averages 5 to 15 percent, mainly gravel and cobbles.
Depth to secondary carbonates: less than 10 inches.
A horizon
Value: 5 to 7 dry and 3 or 4 moist
Chroma: 3 or 4 dry or moist
Texture of the fine earth: silt loam, fine sandy loam, or loam
Clay content: 8 to 15 percent
Rock fragments: 45 to 70 percent gravel, 5 to 30 percent cobbles, and 0 to 5 percent stones; range is 50 to 90 percent
Calcium carbonate equivalent: 0 to 1 percent
Effervescence: noneffervescent or very slightly effervescent
Reaction: slightly or moderately alkaline
Bt horizons
Hue: 7.5YR or 10YR
Value: 5 or 6 dry and 4 or 5 moist
Chroma: 3 or 4 dry or moist
Clay content: 12 to 18 percent
Rock fragments: 15 to 35 percent gravel, 0 to 10 percent cobbles, and 0 to 2 percent stones; range is 15 to 45 percent
Effervescence: noneffervescent or very slightly effervescent
Reaction: slightly or moderately alkaline
Btk1 horizon
Hue: 7.5YR or 10YR
Value: 5 or 6 dry and 4 or 5 moist
Chroma: 3 or 4 dry or moist
Texture of the fine earth: silt loam, loam, or clay loam
Clay content: 18 to 30 percent
Rock fragments: 1 to 10 percent; with 1 to 10 percent gravel, 0 to 3 percent cobbles, and 0 to 2 percent stones.
Calcium carbonate equivalent: 1 to 10 percent
Effervescence: slightly to violently effervescent
Reaction: moderately or strongly alkaline
Btk2 horizon
Hue: 7.5YR or 10YR
Value: 5 or 6 dry and 4 or 5 moist
Chroma: 3 or 4 dry or moist
Texture of the fine earth: silt loam, loam, or clay loam
Clay content: 18 to 30 percent
Rock fragments: 30 to 55 percent; with 30 to 55 percent gravel and 0 to 5 percent cobbles
Calcium carbonate equivalent: 1 to 10 percent
Effervescence: slightly to violently effervescent
Reaction: moderately or strongly alkaline
Btky horizon
Hue: 7.5YR or 10YR
Value: 5 or 6 dry and 4 or 5 moist
Chroma: 3 or 4 dry or moist
Texture of the fine earth: silt loam, loam, or clay loam
Clay content: 18 to 30 percent
Rock fragments: 30 to 55 percent; 30 to 55 percent gravel, 0 to 10 percent cobbles
Calcium carbonate equivalent: 1 to 10 percent
Effervescence: slightly to violently effervescent
Reaction: moderately or strongly alkaline
Gypsum: 1 to 3 percent masses or crystals
Bkq horizon
Value: 6 or 7 dry and 4 to 6 moist
Chroma: 3 or 4 moist
Clay content: 5 to 15 percent
Rock fragments: 35 to 60 percent gravel, 10 to 30 percent cobbles, and 0 to 2 percent stones; range is 45 to 85 percent
Calcium carbonate equivalent: 5 to 20 percent
Effervescence: strongly or violently effervescent
Reaction: moderately or strongly alkaline
Durinodes: 2 to 30 percent
COMPETING SERIES: These are the
Dona Ana,
Headquarters,
Jagerson,
Kidwell,
Mohave, and Nutt series. Dona Ana, Headquarters, Mohave, and Nutt soils receive more rainfall and are moist for more than 20 days cumulative in some part of the soil moisture control section between July and October. Jagerson and Kidwell soils have more than 15 percent rock fragments in the control section. In addition, Jagerson soils allow redder hues in the control section. Kidwell soils are greater than 10 inches to secondary lime, have a thicker epipedon, and have cooler soil temperatures.
GEOGRAPHIC SETTING: The Blackmagic soils are on alluvial fan remnants. Slope ranges from 2 to 4 percent. The soils formed in material from dominantly igneous alluvium. Elevations are 3,000 to 4,000 feet. The climate is arid, with hot, dry summers and warm, moist winters. Most precipitation comes in the winter but in some areas it is sporadic. The mean annual precipitation is 4 to 7 inches. The mean annual temperature is 61 to 66 degrees F. The frost-free season is 240 to 300 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the
Arizo,
Crosgrain, and Pioneer (T) soils. Arizo soils have sandy-skeletal particle-size control sections and are found in inset fans. Crosgrain and Pioneer soils are on ballenas and eroded fan remnants and do not have argillic horizons. In addition, Crosgrain soils are shallow to a duripan and have loamy-skeletal particle-size control sections. Pioneer soils are shallow to a cambidic duripan and have loamy particle-size control sections.
DRAINAGE AND PERMEABILITY: Well drained; low runoff; moderately slow permeability.
USE AND VEGETATION: Blackmagic soils are used for military exercises and wildlife habitat. The present vegetation is mainly annual grasses and perennial shrubs such as creosotebush and white bursage.
DISTRIBUTION AND EXTENT: Mojave Desert of southeastern California. The series is of small extent in MLRA 30.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: PHOENIX, ARIZONA
SERIES ESTABLISHED: San Bernardino County, California, Fort Irwin Soil Survey Area 2000. The name is coined.
REMARKS:
Diagnostic horizons and features recognized in the profile are:
1. Ochric epipedon -- 0 to 2 inches (A)
2. Argillic horizon -- 2 to 45 inches (Bt, Btk, Btky)
3. Calcic horizon -- 45 to 60 inches (Bkq)
4. Durinodic layer -- 45 to 60 inches (Bkq)
5. Particle-size control section -- the zone between 2 and 22 inches (Bt, Btk)
Responsibility for this series was transferred from Davis to Phoenix 4/2015. The last revision to the series was 5/2000. ET
National Cooperative Soil Survey
U.S.A.