LOCATION OLDAD                   CA

Tentative Series
REV: EEM/SMR/LJL/ET
12/2015

OLDAD SERIES

The Oldad series consists of very deep, somewhat excessively drained soils that formed in eolian deposits over alluvium from granitoid, gneiss, diorite and limestone. Oldad soils are on sand sheets over fan remnants. Slopes range from 1 to 8 percent. The mean annual precipitation is about 100 millimeters (4 inches) and the mean annual air temperature is about 21.5 degrees C (71 degrees F).

TAXONOMIC CLASS: Sandy, mixed, hyperthermic Typic Haplocalcids

TYPICAL PEDON: Oldad fine sand, on a west-southwest facing, linear, 3 percent slope under desert shrubs at an elevation of 403 meters (1322 feet). (Colors are for dry soil unless otherwise noted.) The soil surface is covered by approximately 20 percent fine gravel, 29 percent medium and coarse gravel and 1 percent cobbles.

A -- 0 to 4 centimeters (0 to 2 inches); pale brown (10YR 6/3) fine sand, brown (10YR 4/3) moist; weak thick platy structure; soft, very friable, nonsticky and nonplastic; common very fine roots; common very fine and fine interstitial pores; 5 percent fine gravel and 1 percent medium and coarse gravel; neutral (pH 6.7); clear smooth boundary. (1 to 12 centimeters, 0.4 to 5 inches thick)

Ck1 -- 4 to 42 centimeters (2 to 17 inches); pale brown (10YR 6/3) fine sand, brown (10YR 4/3) moist; massive; soft, very friable, nonsticky and nonplastic; common very fine and fine and few medium roots; common fine and medium tubular pores; 5 percent faint, white (10YR 8/1) calcium carbonate coats on rock fragments; 2 percent fine gravel and 1 percent medium and coarse gravel; very slightly effervescent (3 percent calcium carbonate equivalent); slightly alkaline (pH 7.8); gradual wavy boundary.

Ck2 -- 42 to 61 centimeters (17 to 24 inches); light yellowish brown (10YR 6/4) loamy fine sand, brown (10YR 4/3) moist; massive; slightly hard, very friable, nonsticky and nonplastic; common very fine and few fine, medium and coarse roots; common fine tubular pores; 5 percent faint white (10YR 8/1) calcium carbonate coats on rock fragments; 2 percent fine gravel and 1 percent medium and coarse gravel; slightly effervescent (4 percent calcium carbonate equivalent); strongly alkaline (pH 8.6); abrupt wavy boundary. (Combined thickness of the Ck horizons is 49 to 95 centimeters, 19 to 37 inches)

2Bkq -- 61 to 103 centimeters (24 to 41 inches); very pale brown (10YR 7/3) fine sandy loam, brown (10YR 5/3) moist; moderate medium subangular blocky structure; moderately hard, friable, slightly sticky and slightly plastic; few fine and medium roots; common very fine and fine tubular pores; 5 percent very pale brown (10YR 7/4) silica films on rock fragments; 5 percent fine, distinct, white (10YR 8/1), irregular, calcium carbonate masses in the soil matrix with sharp boundaries, 5 percent medium, distinct, white (10YR 8/1), irregular, calcium carbonate masses in the soil matrix with sharp boundaries and 5 percent coarse, distinct, white (10YR 8/1), irregular, calcium carbonate masses in the soil matrix with sharp boundaries; 2 percent medium, distinct, white (10YR 8/1), weakly cemented, irregular calcium carbonate nodules in the soil matrix with sharp boundaries and 60 percent white (10YR 8/1) calcium carbonate coats on rock fragments; 3 percent fine gravel and 1 percent medium and gravel; violently effervescent (13 percent calcium carbonate equivalent); very strongly alkaline (pH 9.5); clear wavy boundary. (15 to 49 centimeters, 6 to 19 inches thick)

2Ck -- 103 to 165 centimeters (41 to 65 inches); pale brown (10YR 6/3) loamy fine sand, brown (10YR 5/3) moist with a discontinuous, 2 to 10 centimeter thick, gravelly loamy sand band constituting 5 percent of the horizon; massive; moderately hard, very friable, nonsticky and nonplastic; few very fine and fine roots; many very fine interstitial pores; 2 percent medium, distinct, white (10YR 8/1), irregular calcium carbonate masses in the soil matrix with sharp boundaries; 6 percent fine gravel, 2 percent medium and coarse gravel and 3 percent cobbles; strongly effervescent (6 percent calcium carbonate equivalent); very strongly alkaline (pH 9.7).

TYPE LOCATION: San Bernardino, California; approximately 15 kilometers (9.25 miles) southeast of Baker, California on Kelso Road; 200 meters (656 feet) east and 250 meters (820 feet) north of the southwest corner of section 29, T. 13N, R. 10E, San Bernardino Base Meridian; 35 degrees, 10 minutes, 40.5 seconds north latitude and 115 degrees, 57 minutes, 1.3 seconds west longitude; USGS Seventeenmile Point, CA 7.5 minute topographic quadrangle; UTM 11S 0595576e 3893279n (DATUM: NAD83).

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 during July to September following convection storms. These soils have a typic-aridic soil moisture regime.

Soil temperature: 22 to 25 degrees C (72 to 77 degrees F).
Surface rock fragments: 20 to 50 percent, dominantly gravel, with 0 to 2 percent cobbles.
Depth to calcic horizon: 50 to 100 centimeters (20 to 40 inches).

Control section -
Rock fragments: 4 to 30 percent gravel.
Clay content: averages 1 to 8 percent.
Organic matter: 0 to 0.25 percent.

A horizon
Value: 4 or 5 moist.
Clay content: 1 to 5 percent.
Rock fragments: 2 to 8 percent gravel.
Effervescence: noneffervescent to slightly effervescent.
Calcium carbonate equivalence of the fine earth fraction: 0 to 5 percent.
Reaction: Neutral to moderately alkaline.

Ck horizon(s)
Hue: 10YR or 2.5Y.
Value: 4 to 6, dry or moist.
Chroma: 3 to 6 dry, 3 or 4 moist.
Texture of the fine earth fraction: fine sand or loamy fine sand.
Clay content: 1 to 5 percent.
Rock fragments: 2 to 10 percent gravel, with 0 to 2 percent cobbles.
Effervescence: very slightly to strongly effervescent.
Calcium carbonate equivalence: 0 to 5 percent.
Reaction: slightly alkaline to very strongly alkaline.
Visible secondary carbonates: 0 to 4 percent calcium carbonate nodules and masses.

2Bkq and/or 2Bk horizon(s)
Hue: 7.5YR or 10YR.
Value: 5 to 7 dry, 4 to 6 moist.
Chroma: 3 or 4, dry or moist.
Texture of the fine earth fraction: loamy sand, loamy fine sand or fine sandy loam.
Clay content: 3 to 12 percent.
Rock fragments: 2 to 25 percent gravel, with 0 to 1 percent cobbles.
Effervescence: strongly or violently effervescent.
Calcium carbonate equivalence of the fine earth fraction: 5 to 15 percent.
Reaction: strongly alkaline or very strongly alkaline.
Visible secondary carbonates: 5 to 25 percent calcium carbonate nodules and masses.

2Ck, 2BCk and/or 2Ckq horizon(s)
Hue: 7.5YR to 2.5Y.
Value: 5 or 6 dry, 4 or 5 moist.
Chroma: 3 or 4, dry or moist.
Texture of the fine earth fraction: fine sand, loamy sand or loamy fine sand.
Clay content: 1 to 6 percent.
Rock fragments: 6 to 55 percent gravel, with 0 to 3 percent cobbles.
Effervescence: very slightly to violently effervescent.
Calcium carbonate equivalence of the fine earth fraction: 3 to 6 percent.
Visible secondary carbonates: 0 to 4 percent calcium carbonate nodules and masses.

COMPETING SERIES: These are the Buzzardsprings (CA) and Superstition (AZ+CA) series. Buzzardsprings soils have a calcic horizon with an upper boundary between 10 and 36 centimeters (3 to 14 inches). Superstition soils are on dunes and have less than 5 percent rock fragments throughout. In addition, Superstition soils receive mostly summer precipitation.

GEOGRAPHIC SETTING: Oldad soils are on sand sheets over fan remnants. Slopes range from 1 to 8 percent. These soils formed in eolian deposits over alluvium from granitoid, gneiss, diorite and limestone. Elevations range from 310 to 725 meters (1017 to 2378 feet). The climate is arid with hot, dry summers and warm, moist winters. The mean annual precipitation is 75 to 125 millimeters (3 to 5 inches); mean annual air temperature is 20 to 23 degrees C (68 to 73.4 degrees F). The frost-free season is 300 to 340 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are Dalelake, Sheephole and Sunmill soils. Dalelake soils are on adjacent sand sheets, Sheephole soils are on adjacent sand sheets over fan aprons and Sunmill soils are on nearby fan remnants. Dalelake soils do not have a calcic horizon. Sheephole soils do not have a calcic horizon and have a horizon within the particle-size control section with greater than 35 percent rock fragments. Sunmill soils have an argillic horizon with its upper boundary 25 to 50 centimeters (10 to 20 inches) below the mineral soil surface.

DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY: Well drained; high saturated hydraulic conductivity.

USE AND VEGETATION: Oldad soils are used for recreation and wildlife habitat. The present vegetation is mainly creosote bush.

DISTRIBUTION AND EXTENT: Mojave Desert of southeastern California, U.S.A., MLRA 30. The series is of small extent.

MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: PHOENIX, ARIZONA

SERIES PROPOSED: San Bernardino, California; Soil Survey of the Mojave National Preserve Area, California, 2012. The name is coined from Old Dad Mountain located 15 kilometers (9 miles) to the south-southeast of the typical pedon.

REMARKS: Diagnostic horizons and features recognized in this pedon include:

Ochric epipedon - from a depth of 0 to 4 centimeters (0 to 2 inches) (A horizon).
Calcic horizon - from a depth of 61 to 103 centimeters (24 to 41 inches) (2Bkq horizon).
Particle-size control section - from a depth of 25 to 100 centimeters (10 to 40 inches) (part of the Ck1, Ck2 and 2Bkq horizons).

ADDITIONAL DATA: NASIS User Pedon ID: 2012CA795170.

Responsibility for this series was transferred from Davis to Phoenix 12/2015. The last revision to the series was 10/2012. ET

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National Cooperative Soil Survey
U.S.A.