LOCATION STUBBESPRING            CA

Established Series
Rev: PRR/CAH/ET
12/2015

STUBBESPRING SERIES

The Stubbespring series consists of very shallow and shallow, well drained soils that formed in colluviums and residuum from granitoid rocks. The Stubbespring soils are on hills. Slopes range from 15 to 50 percent. The mean annual precipitation is about 200 millimeters (8 inches) and the mean annual air temperature is about 15 degrees C (59 degrees F).

TAXONOMIC CLASS: Loamy, mixed, superactive, thermic, shallow Xeric Haplargids

TYPICAL PEDON: Stubbespring coarse sand, on a north-facing (14 degrees), 45 percent slope at an elevation of 1,460 meters (about 4,790 feet). When described the soil was dry throughout. (Colors are for dry soils unless otherwise noted.) The soil surface is covered by 25 percent fine gravel, 30 percent medium and coarse gravel, 15 percent cobbles, 3 percent stones, and 2 percent boulders.

A -- 0 to 3 centimeters (0 to 1 inches); light olive brown (2.5Y 5/3) coarse sand, brown (10YR 5/3) moist; weak fine subangular blocky structure; soft, very friable, nonsticky and nonplastic; few fine and common very fine roots; common fine interstitial pores; slightly alkaline (pH 7.5); clear wavy boundary.

Bw -- 3 to 10 centimeters (1 to 4 inches); light olive brown (2.5Y 5/3) sand, dark olive brown (2.5Y 3/3) moist; weak medium subangular blocky structure; soft, very friable, nonsticky and nonplastic; common fine and many very fine roots; common fine interstitial pores; slightly alkaline (pH 7.4); clear wavy boundary. (6 to 20 centimeters thick)

Bt -- 10 to 32 centimeters (4 to 13 inches); yellowish brown (10YR 5/4) gravelly sandy loam, dark yellowish brown (10YR 4/4) moist; weak coarse subangular blocky structure; hard, firm, slightly sticky and slightly plastic; common very fine, fine and medium roots; common fine irregular and common very fine interstitial pores; 10 percent faint reddish brown (2.5YR 4/4), dry, clay films on rock fragments and 30 percent prominent reddish brown (2.5YR 4/4), dry, clay films on all faces of peds; 15 percent fine gravel and 10 percent medium and coarse paragravel; slightly alkaline (pH 7.6); gradual wavy boundary. (10 to 22 centimeters thick)

Crt -- 32 to 150 centimeters (13 to 59 inches); moderately cemented and moderately weathered granitoid bedrock with fractures greater than 10 centimeters apart; common very fine and few coarse roots in cracks; 5 percent, prominent, reddish brown (2.5YR 4/4), dry, clay films on rock fragments; moderate excavation difficulty.

TYPE LOCATION: Riverside County, California; approximately 4.7 kilometers west of the intersection of Keys View Rd. and Juniper Flat Rd. and due south of Juniper Flat Rd. within Joshua Tree National Park; approximately 390 meters east and 120 meters north of the southwest corner of sec. 25, T. 2S, R. 7E, San Bernardino Base and Meridian; 33 degrees, 57 minutes, 45.8 seconds north latitude and 116 degrees, 12 minutes, 34.1 seconds west longitude; USGS Keys View, California 7.5 minute topographic quadrangle; UTM 11S 573037e 3758304n; (DTM: NAD83).

RANGE IN CHARACTERISTICS:

Soil moisture control section: usually dry from May 1 through November 30, and is moist in some or all parts the rest of the time. Aridic bordering on xeric soil moisture regime.

Soil temperature: 15 to 19 degrees C. (59 to 66 degrees F.)
Surface rock fragments: 30 to 75 percent; with 25 to 35 percent fine gravel, 5 to 30 percent medium and coarse gravel, 0 to 15 percent cobbles, 0 to 3 percent stones and 0 to 2 percent boulders.

Control section
Rock fragments: 5 to 30 percent; gravel.
Clay content: 8 to 16 percent.
Organic matter: 0 to 1 percent.
Effervescence: noneffervescent throughout.
Depth to argillic horizon: 9 to 25 centimeters (4 to 10 inches).
Depth to paralithic contact: 19 to 35 centimeters (7 to 14 inches).

A horizon
Hue: 10YR or 2.5Y.
Value: 3 to 5, moist.
Chroma: 3 or 4 dry, and 2 or 3 moist.
Texture of the fine earth: coarse sand or sandy loam.
Clay content: 3 to 10 percent.
Rock fragments: 5 to 10 percent.

Bw horizon
Hue: 10YR or 2.5Y.
Value: 3 or 4, moist.
Chroma: 3 or 4, dry or moist.
Texture of the fine earth: sand or sandy loam.
Clay content: 4 to 14 percent.
Rock fragments: 5 to 11 percent.

Bt horizon
Value: 4 or 5 dry, and 3 or 4 moist.
Chroma: 4 or 6, dry or moist.
Texture of the fine earth: sandy loam or loam.
Clay content: 8 to 17 percent.
Rock fragments: 3 to 30 percent; with 3 to 20 percent indurated gravel and 0 to 10 percent paragravel.
Reaction: neutral to slightly alkaline.

COMPETING SERIES: This is the Tips (CA) series. Tips soils allow effervescence in the control section.

GEOGRAPHIC SETTING: The Stubbespring soils are on hills. Slopes range from 15 to 50 percent. These soils formed in colluvium and residuum derived from granitoid. Elevations range from 1300 to 1700 meters (4,265 to 5,575 feet). The climate is warm with warm, dry summers and cool, moist winters. The mean annual precipitation is 175 to 250 millimeters (7 to 10 inches) and the mean annual air temperature is 13 to 17 degrees C. The frost free season is 210 to 270 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are Smithcanyon soils. Smithcanyon soils are on similar landscape positions and have a sandy particle-size control section, and do not have an argillic horizon.

DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY: Well drained; high runoff; high saturated hydraulic conductivity above the bedrock and moderately high within the bedrock.

USE AND VEGETATION: Stubbespring soils are used for rangeland and wildlife habitat. The present vegetation is mainly Muller oak, singleleaf pinyon, narrowleaf goldenbush, bigberry manzanita and desert brittlebush.

DISTRIBUTION AND EXTENT: Southern Mojave Desert of southeastern California. MLRA 30. These soils are of small extent.

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

SERIES ESTABLISHED: Riverside County, California; Soil Survey of Joshua Tree National Park, California, 2012. The soil is named for a spring within the survey area.

REMARKS: Diagnostic horizons and features in this pedon include:

Ochric epipedon - from a depth of 0 to 10 centimeters (A and Bw horizons).
Argillic horizon - from a depth of 10 to 32 centimeters (Bt horizon).
Paralithic contact - the zone beginning at 32 centimeters (Crt horizon).
Particle-size control section - 0 to 32 centimeters (A, Bw and Bt horizons).

ADDITIONAL DATA: NASIS USER PEDON ID: 1249720343.

Responsibility for this series was transferred from Davis to Phoenix 12/2015. The last revision to the series was 5/2012. ET

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National Cooperative Soil Survey
U.S.A.