LOCATION MORONGO                 CA

Established Series
Rev: CAH/ET
11/2015

MORONGO SERIES

The Morongo series consists of very deep, somewhat excessively drained soils that formed in alluvium derived from granitoid and/or gneissic rocks. Morongo soils are on fan aprons, inset fans, fan remnants and in drainageways. Slopes range from 2 to 30 percent. The mean annual precipitation is 138 millimeters (5.5 inches) and the mean annual temperature is 18.5 degrees C (65 degrees F).

TAXONOMIC CLASS: Mixed, thermic Typic Torripsamments

TYPICAL PEDON: Morongo sand, on a 2 percent slope under desert rangeland at an elevation of 1,058 meters. When described the soil was dry throughout. (Colors are for dry soil unless otherwise noted). The surface is covered by 70 percent fine gravel and 5 percent medium to coarse gravel.

A -- 0 to 2 centimeters (0 to 1 inches); light yellowish brown (10YR 6/4) sand, yellowish brown (10YR 5/4) moist; weak thick platy structure; soft, very friable, nonsticky and nonplastic; common very fine roots throughout; few very fine interstitial pores; 2 percent fine gravel; neutral (pH 7.2); abrupt smooth boundary. (2 to 23 centimeters thick)

Bw -- 2 to 15 centimeters (1 to 6 inches); yellowish brown (10YR 5/4) sand, dark yellowish brown (10YR 4/4) moist; weak medium subangular blocky structure; soft, very friable, nonsticky and nonplastic; few very fine and fine roots throughout; few very fine irregular pores; 4 percent fine gravel; slightly alkaline (pH 7.4); clear wavy boundary. (0 to 88 centimeters thick)

C1 -- 15 to 70 centimeters (6 to 28 inches); yellowish brown (10YR 5/6) sand, dark yellowish brown (10YR 4/6) moist; massive; soft, very friable, nonsticky and nonplastic; few very fine roots throughout; 6 percent fine gravel and 1 percent medium and coarse gravel; slightly alkaline (pH 7.6); clear wavy boundary.

C2 -- 70 to 150 centimeters (28 to 60 inches); yellowish brown (10YR 5/6) sand, dark yellowish brown (10YR 4/6) moist; single grain; loose, nonsticky and nonplastic; common very fine and fine roots throughout; 5 percent fine gravel; neutral (pH 6.6). (Combined thickness of the C horizons is greater than 75 centimeters.)

TYPE LOCATION: San Bernardino County, California; 950 meters southeast of the corner of Rock Heaven Rd. and Singletree Rd. in the Town of Joshua Tree, 320 north and 150 meters west of the southeast corner of sec. 8, T. 1S, R. 7E., San Bernardino Base and Meridian; USGS Joshua Tree South, California 7.5 minute topographic quadrangle; 34 degrees, 5 minutes, 42.7 sec. north latitude; 116 degrees, 16 minutes, 2.3 sec. west longitude; UTM 11S 567588e 3772954n (DTM: 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 cumulative from July to September following summer convection storms. The soils have a typic-aridic soil moisture regime.

Soil temperature: 15 to 22 degrees C.

Surface rock fragments: ranges from 4 to 75 percent, dominated by gravel.
Effervescence: noneffervescent to slightly effervescent below 100 centimeters (40 inches).

Control section
Rock fragments: averages 3 to 30 percent, dominantly gravel.
Organic matter: 0 to 0.5 percent.
Clay content: 1 to 8 percent.
Effervescence: noneffervescent throughout.

A horizons
Value: 4 to 6 dry, and 2 to 5 moist.
Chroma: 2 to 4, dry or moist.
Texture of the fine earth: sand, loamy coarse sand, loamy sand and loamy fine sand.
Clay content: 1 to 8 percent.
Rock fragments: 2 to 20 percent, dominantly gravel.
Reaction: neutral to slightly alkaline.

Bw or BA horizon (when present)
Value: 4 to 6 dry, and 3 or 4 moist.
Chroma: 3 or 4, dry or moist.
Texture of the fine earth: sand, loamy sand and loamy fine sand.
Clay content: 1 to 8 percent.
Rock fragments: 3 to 20 percent, dominantly gravel.
Reaction: slightly acid to slightly alkaline.

C horizons
Value: 5 or 6 dry; 3 to 5 moist
Chroma: 3 or 4 dry; 2 to 4 moist.
Texture of the fine earth: coarse sand, sand, loamy coarse sand or loamy sand.
Clay content: 1 to 8 percent.
Rock fragments: ranges from 1 to 32 percent, dominantly gravel.
Reaction: neutral to moderately alkaline.

COMPETING SERIES: These are the Azulugar (T TX), Bigcanyon (CA), Birdcanyon (CA), Bluepoint (NV), Brazito (NM), Cajon (CA), Copia (NM), Hembrillo (T NM), Koehn (CA), Maynard Lake (NV), Moapa (NV), Pintura (UT), Toquop (NV), Yander (CA) and Yturbide (NM) series. Azulugar, Bluepoint, Brazito, Cajon, Koehn, Maynard Lake, Moapa, Toquop, and Yturbide soils allow effervescence throughout the control section. In addition, Azulugar soils receive more than 200 millimeters (8 inches) of precipitation, and are moist for more than 20 days cumulative between July and September. Brazito, Copia and Yturbide soils are also intermittently moist in the soil moisture control section for more than 20 days from July to September. Bigcanyon soils formed in colluvium over residuum and have a paralithic contact between 50 and 100 centimeters (20 and 40 inches). Birdcanyon and Koehn soils are not intermittently moist in some part of the control section for 10 to 20 days cumulative between July and September following summer convection storms. Bluepoint and Hembrillo soils formed in eolian materials and allow gypsum in the control section with Hembrillo soils having between 20 and 50 percent gypsum in the control section. Copia soils formed from mixed alluvium and have hues of 2.5YR to 7.5YR. Maynard Lake soils contain more than 20 percent pumice and volcanic ash. Moapa soils have a paralithic contact at a depth of 53 to 98 centimeters (21 to 38 inches), are formed from eolian sands, and are on sand sheets over sandstone rock pediments. Pintura soils have hues of 2.5 YR or 5YR and formed in eolian sands derived from sandstone. Yander soils are formed in alluvium over granitic residuum on fan aprons over pediment and have a paralithic contact between 100 and 150 centimeters (40 and 60 inches).

GEOGRAPHIC SETTING: Morongo soils are on fan aprons, inset fans, fan remnants and in drainageways. Slopes range from 2 to 30 percent. These soils formed in alluvium derived from granitoid and/or gneissic rocks. Elevations range from 650 to 1,550 meters (2,133 to 5,085 feet). The mean annual precipitation is 75 to 175 millimeters (3 to 7 inches) and the mean annual air temperature is 13 to 20 degrees C (55.5 to 68 degrees F). Frost-free season is 210 to 320 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Bluecut, Desertqueen, Jumborox, Helendale and Pinecity soils. Bluecut soils have an argillic horizon with an abrupt upper boundary, a fine-loamy particle size control section, and are located higher on the fan piedmont on adjacent fan aprons over fan remnants. Desertqueen soils are on nearby pediments and hills, have a coarse-loamy particle size control section and an argillic horizon above a shallow paralithic contact. Jumborox and Helendale soils have coarse-loamy particle size control sections, argillic horizons, and are located on fan remnants. Pinecity soils are very shallow and shallow to a paralithic contact and are located on low hills and pediments.

DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY: Somewhat excessively drained; very low to low runoff; high saturated hydraulic conductivity. The soils can be very rarely flooded on fan aprons and fan remnants and rarely to frequently flooded in drainageways.

USE AND VEGETATION: This soil is used for rangeland, wildlife habitat and urban land. Vegetation is mainly burrobush, creosote bush, Nevada ephedra, big galleta, and white ratany.

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

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

SERIES ESTABLISHED: San Bernardino County, California; Soil Survey of Joshua Tree National Park, California, 2012. The name is from the town of Morongo Valley which is just northwest of the survey area.

REMARKS: Diagnostic horizons and features in this pedon include:

Ochric epipedon - from a depth of 0 to 15 centimeters. (A and Bw horizons)
Particle-size control section - from a depth of 25 to 100 centimeters.
(part of the C1 and C2 horizons)

ADDITIONAL DATA: NASIS User Pedon ID: 1249800836.

Responsibility for this series was transferred from Davis to Phoenix 11/2015. The last revision to the series was 5/2012. ET

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National Cooperative Soil Survey
U.S.A.