LOCATION BALDSPOT CA

Established Series
SMR/CAH/ET
02/2025

BALDSPOT SERIES

The Baldspot series consists of very shallow and shallow to a petrocalcic, well drained soils that formed in alluvium derived from igneous and sedimentary rock. The Baldspot soils are on fan remnants. Slopes range from 1 to 4 percent. The mean annual precipitation is about 150 mm, and the mean annual temperature is about 18 degrees C.

TAXONOMIC CLASS: Loamy, mixed, superactive, thermic, shallow Calcic Petrocalcids

TYPICAL PEDON: Baldspot sandy loam, on a northeast facing, 1 percent slope under rangeland at an elevation of 1,039 meters. (Colors are for dry soils unless otherwise noted. 9/27/2011 actual site observation date.) The soil surface is covered by approximately 12 percent fine gravel, 8 percent medium and coarse gravel.

A--0 to 8 cm (0 to 3 inches); pale brown (10YR 6/3) sandy loam, yellowish brown (10YR 5/4), moist; strong thick platy structure; slightly hard, very friable, slightly sticky and nonplastic; common very fine roots throughout; many very fine irregular and common very fine vesicular pores; 2 percent fine gravel, 2 percent medium and coarse gravel; violent effervescence (10 percent calcium carbonate equivalent); strongly alkaline (pH 8.5); clear wavy boundary. (3 to 8 cm thick)

Bk--8 to 28 cm (3 to 11 inches); pale brown (10YR 6/3) sandy loam, yellowish brown (10YR 5/4), moist; moderate coarse subangular blocky structure; slightly hard, very friable, slightly sticky and slightly plastic; common very fine roots throughout; common fine tubular and common medium tubular and common very fine irregular and common very fine dendritic tubular pores; 3 percent medium prominent irregular moderately coherent cemented white (10YR 8/1), dry, carbonate nodules with sharp boundaries in matrix and 2 percent medium prominent irregular noncoherent cemented white (10YR 8/1), dry, carbonate masses with sharp boundaries in matrix and 5 percent coarse prominent irregular moderately coherent cemented white (10YR 8/1), dry, carbonate nodules with sharp boundaries in matrix; 3 percent fine gravel, 2 percent medium and coarse gravel; violent effervescence (16 percent calcium carbonate equivalent); strongly alkaline (pH 8.5); abrupt smooth boundary. (15 to 30 cm thick)

Bkkq--28 to 76 cm (11 to 30 inches); white (10YR 8/1) cemented sandy loam, very pale brown (10YR 7/3), moist; massive; very hard, firm, very weakly coherent by carbonates, slightly sticky and nonplastic; common fine roots in cracks and few medium roots in cracks and common very fine roots in cracks; 2 percent distinct light gray (10YR 7/2) silica coats on nodules and 100 percent prominent white (10YR 8/1) carbonate coats on rock fragments; 1 percent very fine faint platy strongly coherent cemented light gray (10YR 7/1) silica concretions with sharp boundaries at top of horizon; 8 percent fine gravel, 4 percent medium and coarse gravel; violent effervescence (30 percent calcium carbonate equivalent); strongly alkaline (pH 8.7); abrupt wavy boundary. (35 to 60 cm thick)

Bkkqm--76 to 90 cm (30 to 35 inches); white (10YR 8/1) cemented loamy sand, light gray (10YR 7/2), moist; massive; extremely hard, extremely firm, moderately coherent by carbonates, slightly sticky and nonplastic; common very fine roots top of horizon; 2 percent distinct light gray (10YR 7/2) silica coats on nodules; 8 percent fine gravel, 4 percent medium and coarse gravel; violent effervescence (30 percent calcium carbonate equivalent).

TYPE LOCATION: San Bernardino County, California; about 12 miles north of Goffs, California located in the southeast corner of Lainfair Valley; approximately 550 feet east and 1,800 feet north of the southwest corner of section 22, T. 12 N., R. 18 E., San Bernardino Baseline and Meridian; USGS Signal Hill, California 7.5 minute topographic quadrangle; 35 degrees, 6 minutes, 14.70 seconds north latitude and 115 degrees, 1 minutes, 52.72 seconds west longitude; UTM zone 11 679429e, 3886359n, NAD83.

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: 19 to 22 degrees C (66 to 72 degrees F).
Depth to calcic horizon: 3 to 20 centimeters (1 to 8 inches).
Depth to petrocalcic contact: 20 to 36 centimeters (8 to 14 inches).
Reaction: moderately alkaline or strongly alkaline.

Control section
Rock fragments: 0 to 25 percent.
Clay content: 6 to 14 percent.
Organic matter: 0 to 0.25 percent.

A horizon
Hue: 10YR or 7.5YR, moist.
Value: 5 or 6 dry, 4 or 5 moist.
Chroma: 3 or 4 dry and moist.
Rock fragments: 0 to 15 percent.
Effervescence: slight to violently effervescent.
Calcium carbonate equivalence of the fine earth fraction: 0 to 15 percent.

Bk or Bkq horizons
Hue: 10YR, 2.5Y or 7.5YR, moist.
Value: 5 or 6 dry, 4 to 6 moist.
Chroma: 3 or 4 dry and moist.
Texture of the fine earth: sandy loam or fine sandy loam.
Rock fragments: 0 to 25 percent, dominantly gravel.
Effervescence: strongly or violently effervescent.
Calcium carbonate equivalence of the fine earth fraction: 10 to 30 percent
Visible secondary carbonates: 5 to 30 percent masses and nodules.

Bkk, Bkkm, Bkkq or Bkkqm horizons
Value: 7 or 8 dry, 6 or 7 moist.
Chroma: 1 or 2 dry, 2 to 4 moist.
Texture of the fine earth: sand, loamy sand or sandy loam.
Clay content: 2 to 10 percent.
Rock fragments: 0 to 25 percent, dominantly gravel.
Calcium carbonate equivalence of the fine earth fraction: 20 to 40 percent.
Cementation: 60 to 100 percent, very weakly to strongly cemented.

COMPETING SERIES: These are the Bella (AZ), Culberspeth (TX), Flyby (CA), and Shumla (TX) series. All series have petrocalcic horizons that are indurated and an aridic bordering on ustic soil moisture regime. In addition, Bella soils contain gypsum within and below the petrocalcic horizon, and the petrocalcic horizon is 13 to 38 cm thick. Culberspeth and Flyby soils have a mean annual soil temperature of 16 to 19 and 15 to 19 degrees C, respectively. Shumla soils have a lithic contact between 50 and 100 cm.

GEOGRAPHIC SETTING: The Baldspot soils are on fan remnants. Slopes range from 1 to 4 percent. The soils formed in alluvium derived from igneous and sedimentary rock. Elevation ranges from 900 to 1,150 meters. The mean annual precipitation is 125 to 175 mm. The mean annual air temperature is about 17 to 20 degrees C. The frost-free period is 270 to 320 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Castaneda and Caruthers soils. Castaneda soils occur on fan remnants, have an argillic horizon with a fine-loamy particle-size control section and have a moderately deep petrocalcic horizon. Caruthers soils are on fan remnants, have an argillic horizon with a coarse-loamy particle-size control section, and have a deep petrocalcic horizon.

DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY: Well drained; high runoff; moderately high saturated hydraulic conductivity in the upper part and low within the petrocalcic part.

USE AND VEGETATION: Baldspot soils are used for recreation and wildlife habitat. Native vegetation is burrobush, creosote bush, winterfat, Joshua tree, and big galleta.

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, 2023. The name is coined.

REMARKS: Diagnostic horizons and features in this pedon include:

Ochric epipedon - the zone from 0 to 8 cm (A horizon).
Calcic horizon - the zone from 8 to 28 cm (Bk horizon)
Petrocalcic horizon - the zone from 28 to 90 cm (Bkkq and Bkkqm horizons).
Particle size control section - the zone from 0 to 28 cm (A and Bk horizons).

ADDITIONAL DATA: NASIS User/Pedon Site ID: 2011CA071070.

National Cooperative Soil Survey
U.S.A.