LOCATION PERUROSE                CA

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

PERUROSE SERIES

The Perurose series consists of moderately deep, somewhat excessively drained soils that formed in alluvium from granitoid and/or gneissic rocks. Perurose soils are on fan remnants. Slopes range from 2 to 15 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 Cambidic Haplodurids

TYPICAL PEDON: Perurose gravel, on a south-facing, convex, 3 percent slope under sparse desert shrubs at an elevation of 320 meters (1,050 feet). (Colors are for dry soil unless otherwise noted.)

C -- 0 to 5 centimeters (0 to 2 inches) gravel; approximately 35 percent fine gravel, 30 percent medium and coarse gravel and 15 percent cobbles; abrupt smooth boundary. (0 to 7 centimeters thick)

A -- 5 to 7 centimeters (2 to 3 inches); very pale brown (10YR 7/4) loamy fine sand, brown (10YR 5/3) moist; weak thin platy structure; soft, very friable, nonsticky and nonplastic; few very fine roots; few very fine, fine, and medium vesicular pores; 7 percent fine gravel and 3 percent medium and coarse gravel; violently effervescent; strongly alkaline (pH 8.7); clear wavy boundary. (1 to 7 centimeters thick)

Bk -- 7 to 18 centimeters (3 to 7 inches); very pale brown (10YR 7/4) loamy fine sand, light yellowish brown (10YR 6/4) moist; weak fine subangular blocky structure parting to massive; slightly hard, very friable, nonsticky and nonplastic; few very fine and fine roots; 4 percent fine gravel and 1 percent medium and coarse gravel; violently effervescent; strongly alkaline (pH 8.9); clear wavy boundary.

Bkq -- 18 to 45 centimeters (7 to 18 inches); very pale brown (10YR 7/4) loamy sand, light yellowish brown (10YR 6/4) moist; weak medium subangular blocky structure parting to massive; slightly hard, very friable, nonsticky and nonplastic; very few fine, medium and coarse roots; 7 percent fine and 5 percent medium, irregular, weakly cemented durinodes within the matrix; 5 percent fine gravel; violently effervescent; strongly alkaline (pH 8.6); gradual wavy boundary.

C -- 45 to 76 centimeters (18 to 30 inches); brownish yellow (10YR 6/6) sand, dark yellowish brown (10YR 4/4) moist; single grain; soft, very friable, nonsticky and nonplastic; very few fine roots; 6 percent fine gravel and 1 percent medium and coarse gravel; very slightly effervescent; moderately alkaline (pH 8.3); abrupt smooth wavy boundary. (Combined thickness of the B and C horizons is 50 to 88 centimeters).

2Bkqm -- 76 to 110 centimeters (30 to 43 inches); very pale brown (10YR 7/4) moderately cemented sand, light yellowish brown (10YR 6/4) moist; continuous duripan with 100 percent cementation; massive; very hard, extremely firm, nonsticky and nonplastic; violently effervescent; clear wavy boundary. (9 to 75 centimeters thick)

2C -- 110 to 152 centimeters (43 to 60 inches); very pale brown (10YR 7/3) gravelly sand, pale brown (10YR 6/3) moist; single grain; loose, nonsticky and nonplastic; 20 percent fine gravel and 5 percent medium and coarse gravel; slightly effervescent; moderately alkaline (pH 8.4).

TYPE LOCATION: Riverside County, California; approximately 11 kilometers (6.8 miles) northwest of the junction of Highway 177 and MWD Aqueduct Road, 1 kilometer (0.6 miles) north of the junction of MWD Powerline Road and MWD Aqueduct Road; 735 meters (2,410 feet) north and 690 meters (2,260 feet) west of the SE corner of section 25, T. 3 S., R. 15 E., San Bernardino Base and Meridian; 33 degrees, 52 minutes and 51.3 seconds north latitude and 115 degrees, 21 minutes and 40.7 seconds west longitude; USGS Coxcomb Mountains 7.5 minute topographic quadrangle; UTM 11S 0651550e 3750162n (DTM: NAD83).

RANGE IN CHARACTERISTICS:

Soil moisture control section: usually dry, moist in some parts for short
periods during winter and early spring and for 10 to 20 days cumulative
between July and September following summer convection storms. The soils have a typic-aridic soil moisture regime.

Soil temperature: 22 to 25 degrees C (72 to 77 F).
Surface rock fragments: 40 to 95 percent; with 25 to 50 percent fine
gravel, 15 to 55 percent medium and coarse gravel, 0 to 20 percent
cobbles, and 0 to 5 percent stones.

Control section -
Rock fragments: averages 5 to 30 percent; mainly gravel, with some
cobbles and stones.
Clay content: 1 to 10 percent.
Organic matter: 0 to 0.25 percent.
Depth to the upper boundary of a duripan: 50 to 100 centimeters (20 to 40 inches).

C horizon (when present)
80 to 95 percent rock fragments; with 20 to 50 percent fine gravel, 20
to 55 percent medium and coarse gravel and 0 to 20 percent cobbles.

A horizon
Hue: 10YR or 2.5Y.
Value: 5 to 7 dry, and 3 to 6, moist.
Chroma: 3 or 4 dry, and 3 to 6, moist.
Texture of the fine earth: sand, fine sand, loamy sand, loamy fine sand or fine sandy loam. Clay content: 1 to 12 percent.
Rock fragments: 1 to 14 percent gravel.
Effervescence: noneffervescent to violently effervescent.
Calcium carbonate equivalent: 0 to 10 percent.
Reaction: slightly to strongly alkaline.

Bk(q) horizons
Hue: 7.5YR, 10YR or 2.5Y.
Value: 5 to 8 dry, and 4 to 7, moist.
Chroma: 2 to 6, dry or moist.
Texture of the fine earth: sand, fine sand, loamy coarse sand, loamy sand, loamy fine sand or fine sandy loam. Clay content: 1 to 12 percent.
Rock fragments: 1 to 35 percent; with 1 to 30 percent gravel and 0 to 10 percent cobbles. Effervescence: noneffervescent to violently effervescent.
Calcium carbonate equivalent: 0 to 15 percent.
Reaction: slightly to very strongly alkaline.
Silica: 0 to 20 percent as coats on bottom of rock fragments and 0 to 40 percent weakly or moderately cemented durinodes.

2Bkqm or 2Bkq horizon
Hue: 10YR or 2.5Y.
Value: 6 to 8 dry, and 4 to 7, moist.
Chroma: 2 to 4, dry and 3 or 4, moist.
Texture of the fine earth: sand, loamy coarse sand or loamy sand.
Clay content: 1 to 6 percent,.
Rock fragments: 3 to 15 percent, 0 to 10 percent gravel.
Calcium carbonate equivalent: 1 to 10 percent.
Reaction: neutral to moderately alkaline.
Cementation: weakly to strongly cemented, 75 to 100 percent continuity.
2C or 2Ck horizon
Hue: 10YR or 2.5Y.
Value: 6 or 7, dry and 5 or 6, moist.
Chroma: 2 to 4, dry or moist.
Texture of the fine earth: coarse sand, sand or loamy sand. Clay content: 1 to 6 percent.
Rock fragments: 5 to 30 percent gravel.
Effervescence: slightly to violently effervescent.
Calcium carbonate equivalent: 0 to 5 percent.
Reaction: slightly to strongly alkaline.

COMPETING SERIES: There are no competing series at this time.

GEOGRAPHIC SETTING: Perurose soils are on fan remnants. Slopes range from 2 to 15 percent. These soils formed in alluvium from granitoid and/or gneissic rocks. Elevations range from 290 to 780 meters (951 to 2,560 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) and the mean annual air temperature is 20 to 23 degrees C (68 to 73.5 degrees F). The frost-free season is 300 to 340 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Coxpin and Pintobasin soils. Coxpin soils are on similar landscape positions and Pintobasin soils are on adjacent fan aprons. Coxpin soils are 36 to 50 centimeters deep to a weakly to moderately cemented duripan. Pintobasin soils are very deep and have no diagnostic horizons.

DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY: Somewhat excessively drained; low runoff; high saturated hydraulic conductivity above and below the duripan and moderately low saturated hydraulic conductivity within the duripan.

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

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 name is from a location in the survey area.

REMARKS: Diagnostic horizons and features in this pedon include:

Ochric epipedon - from a depth of 0 to 2 centimeters (A horizon).
Duripan - from a depth of 71 to 105 centimeters (2Bkqm horizon).
Particle-size control section - from a depth of 25 to 71 centimeters
(part of the Bkq and C horizons).

ADDITIONAL DATA: NASIS User Pedon ID: 12480147-H.

Responsibility for this series was transferred from Davis to Phoenix 12/2015. The last revision to the series was 6/2012. ET

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National Cooperative Soil Survey
U.S.A.