LOCATION DARKMAGIC               CA

Established Series
NHK/LJL/MEB
02/2025

DARKMAGIC SERIES

The Darkmagic series consists of moderately deep to bedrock, well drained soils that formed in loess influenced residuum weathered from basalt. The Darkmagic soils are on lava flows. Slopes range from 2 to 15 percent. The mean annual precipitation is about 193 mm, and the mean annual temperature is about 18 degrees C.

TAXONOMIC CLASS: Fine-loamy, mixed, superactive, thermic Typic Calciargids

TYPICAL PEDON: Darkmagic loam, on a northwest facing, 3 percent slope under rangeland at an elevation of 940 meters. (Colors are for dry soils unless otherwise noted. 3/16/2020 actual site observation date.) The soil surface is covered by approximately 5 percent fine gravel, 40 percent medium and coarse gravel, 30 percent cobbles, 5 percent stones.

V--0 to 5 cm (0 to 2 inches); brown (10YR 5/3) loam, brown (10YR 4/3), moist; strong thick platy structure; slightly hard, very friable, slightly sticky and slightly plastic; few very fine roots; many fine vesicular and many very fine vesicular pores; 2 percent fine gravel, 3 percent medium and coarse gravel, 2 percent cobbles; strong effervescence; strongly alkaline (pH 8.6); 18 percent calcium carbonate equivalent of the fine-earth fraction; clear smooth boundary.

Vtk--5 to 9 cm (2 to 4 inches); brown (7.5YR 5/4) silt loam, brown (7.5YR 4/4), moist; strong thick platy structure; slightly hard, very friable, slightly sticky and slightly plastic; many fine vesicular and many very fine vesicular pores; 40 percent distinct strong brown (7.5YR 5/8) clay films on all faces of peds; 3 percent faint irregular noncoherent cemented very pale brown (10YR 8/2) carbonate masses with clear boundaries in matrix; 1 percent fine gravel, 2 percent medium and coarse gravel; strong effervescence; strongly alkaline (pH 8.6); 20 percent calcium carbonate equivalent of the fine-earth fraction; clear smooth boundary. (Combined thickness of the V horizons is 4 to 10 cm.)

Btky1--9 to 26 cm (4 to 10 inches); light brown (7.5YR 6/4) clay loam, brown (7.5YR 5/4), moist; moderate fine subangular blocky structure; moderately hard, very friable, slightly sticky and slightly plastic; common very fine irregular pores; faint very pale brown (10YR 8/2) carbonate coats and 40 percent distinct strong brown (7.5YR 5/8) clay films on all faces of peds; 7 percent faint irregular noncoherent cemented very pale brown (10YR 8/2) carbonate masses with clear boundaries in matrix and 1 percent medium distinct gypsum crystals, unspecified; 3 percent fine gravel, 2 percent medium and coarse gravel; strong effervescence; strongly alkaline (pH 8.5); 20 percent calcium carbonate equivalent of the fine-earth fraction; gradual wavy boundary.

Btky2--26 to 49 cm (10 to 19 inches); yellowish brown (10YR 5/4) gravelly loam, dark yellowish brown (10YR 4/4), moist; moderate fine subangular blocky structure; slightly hard, very friable, slightly sticky and slightly plastic; common very fine irregular pores; faint very pale brown (10YR 8/2) carbonate coats and 10 percent faint brown (10YR 4/3) clay films on all faces of peds; 7 percent faint irregular noncoherent cemented very pale brown (10YR 8/2) carbonate masses with clear boundaries in matrix and 1 percent medium distinct gypsum crystals, unspecified; 18 percent fine gravel, 7 percent medium and coarse gravel, 1 percent cobbles; strong effervescence; strongly alkaline (pH 8.5); 15 percent calcium carbonate equivalent of the fine-earth fraction; gradual wavy boundary.

Btky3--49 to 74 cm (19 to 29 inches); light yellowish brown (10YR 6/4) gravelly loam, yellowish brown (10YR 5/4), moist; moderate fine subangular blocky structure; soft, very friable, slightly sticky and slightly plastic; few fine irregular and common very fine irregular pores; faint very pale brown (10YR 8/2) carbonate coats and 10 percent faint brown (10YR 4/3) clay films on all faces of peds; 3 percent faint irregular noncoherent cemented very pale brown (10YR 8/2) carbonate masses with clear boundaries in matrix and 1 percent medium distinct gypsum crystals, unspecified; 15 percent fine gravel, 10 percent medium and coarse gravel, 2 percent cobbles; strong effervescence; strongly alkaline (pH 8.8); 9 percent calcium carbonate equivalent of the fine-earth fraction; very abrupt wavy boundary. (Combined thickness of the B horizons is 40 to 75 cm.)

R--74 to 99 cm (29 to 39 inches); indurated basalt bedrock (fractures 45 to <100 cm apart).

TYPE LOCATION: San Bernardino County, California; located in the Cinder Cone Lava Beds 18 miles northwest of Kelso, CA; located in the Cinder Cone Lava Beds area of Mojave National Preserve, CA; approximately 1880 feet east and 640 feet north of the southwest corner of section 3, T. 13 N., R. 11 E., San Bernardino Baseline and Meridian; USGS Indian Spring, California 7.5 minute topographic quadrangle; 35 degrees, 13 minutes, 54.94 seconds north latitude and 115 degrees, 49 minutes, 33.87 seconds west longitude; UTM zone 11 608908e, 3899781n, 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 the base of the argillic horizon: 50 to 100 cm.
Depth to bedrock: 50 to 100 cm.

Control section
Rock fragments: averages 15 to 30 percent, ranges from 5 to 35 percent
Clay content: averages 18 to 35 percent, ranges from 16 to 35 percent.
Sand content: 20 to 40 percent.

V or A horizon(s)
Hue: 10YR or 7.5YR.
Value: 5 or 6 dry, 4 or 5 moist.
Chroma: 3 or 4.
Effervescence: slightly effervescent to violently effervescent.
Reaction: moderately alkaline or strongly alkaline.
Calcium carbonate equivalence of the fine earth: 10 to 25 percent.
Sodium Adsorption Ratio: 5 to 12.
Electrical conductivity: 0 to 2.

Bk horizon (when present)
Hue: 10YR.
Value: 5 or 6 dry, 4 moist.
Chroma: 3 or 4 dry, 4 moist.
Texture: sandy loam or loam.
Clay content: 6 to 12 percent.
Structure: weak, medium or coarse, subangular blocky.
Consistence: soft, very friable, nonsticky or slightly sticky and nonplastic or slightly plastic.
Rock fragments: 0 to 15 percent, mainly gravel.
Effervescence: slightly effervescent to violently effervescent.
Reaction: slightly alkaline or moderately alkaline.

Btky, Btk or Btkk horizon(s)
Hue: 10YR or 7.5YR.
Value: 4 to 7 dry, 4 or 5 moist.
Chroma: 3 or 4.
Texture: clay loam or loam.
Structure: moderate or strong, fine or medium, angular blocky or subangular blocky.
Consistence: soft to hard, very friable or friable, slightly sticky to very sticky and slightly plastic to very plastic.
Rock fragments: 0 to 35 percent, mainly gravel.
Effervescence: strongly effervescent to violently effervescent.
Calcium carbonate equivalence of the fine earth: 10 to 30 percent in the calcic horizon, and 5 to 15 percent in the non-calcic horizon when present.
Sodium Adsorption Ratio: 5 to 12.
Electrical conductivity: 0 to 4.
Gypsum: 0 to 1 percent secondary crystals.

COMPETING SERIES: These are the Blackmagic, Brenda, Cornville, Dona Ana, Elizario, Hap, Jagerson, Kidwell, Lanip, Madurez, Mcnew, Mohave, Nutt, Poachie and Tres Hermanos series. All competing series do not have bedrock at a depth of 50 to 100 centimeters. Blackmagic, Cornville, Dona Ana, Elizario, Madurez, Mcnew, Mohave and Poachie soils have less than 15 percent rock fragments in the control section. Cornville, Dona Ana, Elizario and Madurez soils have more than 50 percent sand in their control-sections.

GEOGRAPHIC SETTING: The Darkmagic soils are on lava flows. Slopes range from 2 to 15 percent. The soils formed in loess influenced residuum weathered from basalt. Elevation ranges from 700 to 1250 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 Dime and Lavatank series. Dime soils are on fan remnants, are very deep and do not have an argillic horizon. Lavatank soils are on cinder cones and "aa" lava flows, do not have an argillic or a calcic horizon, and have a cindery minerology.

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

USE AND VEGETATION: Darkmagic soils are used for recreation and wildlife habitat. Native vegetation is creosote bush, Nevada ephedra, and Spanish dagger.

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 9 cm.
Argillic horizon - the zone from 9 to 74 cm.
Calcic horizon - the zone from 9 to 49 cm.
Lithic contact - the zone from 74 to 99 cm.
Particle size control section - the zone from 9 to 59 cm.

ADDITIONAL DATA: NASIS User/Pedon Site ID: 2020CA0718239.
Located on basalt flows ranging from 200,000 to 750,000 years ago.

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National Cooperative Soil Survey
U.S.A.