LOCATION JUMBOROX                CA

Established Series
Rev: PRR/CAH/ET
09/2015

JUMBOROX SERIES

The Jumborox series consists of very deep, well drained soils that formed in alluvium derived from granite, granitoid or gneissic rocks. The Jumborox soils are on fan remnants. Slopes range from 2 to 15 percent. The mean annual precipitation is 138 millimeters (5.5 inches) and the mean annual air temperature is about 15 degrees C (59 degrees F).

TAXONOMIC CLASS: Coarse-loamy, mixed, superactive, thermic Typic Haplargids

TYPICAL PEDON: Jumborox sand, on a linear, 2 percent slope at an elevation of 1,386 meters (4,545 feet). (Colors are for dry soils unless otherwise noted.) The surface is covered by approximately 10 percent fine gravel, and 5 percent medium and coarse gravel.

A1 -- 0 to 3 centimeters (0 to 1 inch); light olive brown (2.5Y 5/3) sand, dark olive brown (2.5Y 3/3) moist; weak very fine subangular blocky structure parting to single grain; soft, very friable, nonsticky and nonplastic; common very fine roots throughout; 1 percent fine gravel and 1 percent medium and coarse gravel; slightly alkaline (pH 7.6); clear wavy boundary.

A2 -- 3 to 10 centimeters (1 to 4 inches); brown (10YR 5/3) loamy sand, dark brown (10YR 3/3) moist; weak coarse subangular blocky structure; soft, very friable, nonsticky and nonplastic; many very fine and very few fine roots throughout; common fine interstitial pores; 1 percent fine gravel, 1 percent medium and coarse gravel; slightly alkaline (pH 7.6); abrupt smooth boundary. (3 to 25 centimeters thick)

Bt1 -- 10 to 35 centimeters (4 to 14 inches); yellowish brown (10YR 5/4) sandy loam, dark yellowish brown (10YR 3/4) moist; moderate medium subangular blocky structure; slightly hard, very friable, slightly sticky and nonplastic; common fine and few medium and coarse roots throughout; common very fine interstitial and fine dendritic tubular pores; 10 percent faint yellowish brown (10YR 5/4) clay bridges between sand grains; 1 percent fine gravel; slightly alkaline (pH 7.6); clear wavy boundary.

Bt2 -- 35 to 55 centimeters (14 to 22 inches); dark yellowish brown (10YR 4/4) sandy loam, dark yellowish brown (10YR 3/4) moist; moderate medium subangular blocky structure; slightly hard, very friable, slightly sticky and nonplastic; common very fine and medium roots throughout; common very fine dendritic tubular and medium tubular pores; 15 percent distinct dark yellowish brown (10YR 4/6) clay films on surfaces along pores and 20 percent faint dark yellowish brown (10YR 4/4) clay bridges between sand grains; slightly alkaline, (pH 7.7); clear wavy boundary.

Bt3 -- 55 to 93 centimeters (22 to 37 inches); dark yellowish brown (10YR 4/4) loamy sand, dark yellowish brown (10YR 3/4) moist; weak medium subangular blocky structure; slightly hard, very friable, slightly sticky and nonplastic; many very fine and common medium roots throughout; common fine dendritic tubular and very fine interstitial pores; 3 percent faint dark yellowish brown (10YR 4/6) clay films on faces of peds and 20 percent faint dark yellowish brown (10YR 4/4) clay bridges between sand grains; 1 percent fine gravel; slightly alkaline (pH 7.7); clear wavy boundary. (Combined thickness of Bt horizons is 25 centimeters to 130 centimeters thick)

BCt -- 93 to 180 centimeters (37 to 71 inches); yellowish brown (10YR 5/4) loamy sand, dark yellowish brown (10YR 3/4) moist; weak medium subangular blocky structure; slightly hard, very friable, nonsticky and nonplastic; 5 percent strong brown (7.5YR 5/6) clay bridges between sand grains; 2 percent fine gravel; moderately alkaline (pH 8.0).

TYPE LOCATION: San Bernardino County, California; approximately 1 kilometer south of the intersection of Lost Horse Mine Rd. and Keys View Rd. and 215 meters east of Keys View Rd.; approximately 349 meters north and 431 meters east of the southwest corner of sec. 32, T.2 S., R.8 E., San Bernardino Base and Meridian; 33 degrees, 56 minutes, 59.4 seconds north latitude, and 116 degrees, 10 minutes, 15.3 seconds west longitude; USGS Keys View 7.5 minute quadrangle; UTM 11S 576610e, 3756903n (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: 15 to 19 degrees C.
Surface rock fragments: ranges from 5 to 79 percent; with 5 to 70 percent fine gravel, 0 to 40 percent medium and coarse gravel and 0 to 3 percent cobbles.

Control section
Rock fragments: 1 to 20 percent, dominantly gravel.
Organic matter: 0 to 0.5 percent.
Clay content: 8 to 18 percent.
Depth to argillic horizon: 3 to 25 centimeters (1 to 10 inches).

A horizon(s)
Hue: 2.5Y or 10YR.
Value: 4 to 6 dry, and 3 to 5 moist.
Chroma: 3 to 6, dry or moist.
Texture of the fine earth: sand, loamy sand, sandy loam, or fine sandy loam.
Clay content: 2 to 10 percent.
Rock fragments: 1 to 25 percent, dominantly fine gravel.
Effervescence: noneffervescent to very slightly effervescent.
Reaction: slightly acid to slightly alkaline.

Bw and/or BA horizon (when present)
Value: 4 or 5 dry, and 3 or 4 moist.
Chroma: 3 to 4, dry or moist.
Texture of the fine earth: sand, loamy sand, sandy loam.
Clay content: 2 to 8 percent.
Rock fragments: 3 to 7 percent, dominantly fine gravel.
Reaction: neutral or slightly alkaline.

Bt or Btk horizon(s)
Hue: 10YR or 7.5YR.
Value: 4 or 5 dry, and 3 to 5 moist.
Chroma: 3 to 6, dry or moist.
Texture of the fine earth: loamy sand, coarse sandy loam or sandy loam.
Clay content: 6 to 18 percent.
Rock fragments: 1 to 25 percent, predominantly gravel.
Reaction: neutral to moderately alkaline.
Note: Secondary carbonates exist below 40 centimeters in some pedons.


BC or BCt horizon(s) (when present)
Hue: 7.5YR or 10YR.
Value: 4 to 6 dry, and 3 to 5 moist.
Chroma: 4 or 6 dry, and 3 or 4 moist.
Texture of the fine earth: loamy coarse sand or loamy sand.
Clay content: 2 to 8 percent.
Rock fragments: 2 to 30 percent, dominantly fine gravel.
Reaction: slightly or moderately alkaline.

C or Ck horizon(s) (when present)
Hue: 7.5YR or 10YR.
Value: 4 to 6, dry; 3 to 5, moist.
Chroma: 4 to 6, dry; 3 to 5, moist.
Texture of the fine earth: coarse sand, sand, loamy coarse sand, and loamy sand.
Clay content: 2 to 8 percent.
Rock fragments: 5 to 20 percent, dominantly fine gravel.
Effervescence: slightly to strongly effervescent.
Reaction: neutral to moderately alkaline.

COMPETING SERIES: These are the Dovecanyon (CA), Friedliver (CA), Goldivide (CA), Goldpeak (CA), Helendale (CA), Hexie (CA), Littelfargo (CA), Searchlight (NV), Sonoita (AZ), Tray (CA), and Wingap (CA) soils. Dovecanyon, Goldpeak, and Wingap soils are not moist for 10 to 20 days cumulative between July and September. Dovecanyon, Friedliver, Helendale, Hexie and Searchlight soils all have a mean annual soil temperatures of 19 to 22 degrees C. Dovecanyon soils also have no secondary carbonates. Friedliver soils also have an argillic with an upper boundary between 25 and 50 centimeters from the mineral soil surface. Goldivide soils have an argillic horizon 50 to 100 centimeters below the mineral soil surface. Goldpeak soils are noneffervescent throughout. Hexie and Littlefargo soils are moderately deep and have a paralithic contact between 50 and 100 centimeters. Searchlight soils are moderately to strongly alkaline throughout the control section, and have 5 percent or more calcium carbonate equivalent throughout the series size control section. Sonoita soils are intermittently moist for more than 20 days following summer convection storms. The Tray soils are moderately well drained and have strongly or very strongly alkaline horizons that have an ESP of 15 to 30 within the particle size control section. Wingap soils have a paralithic contact within 100 to 150 centimeters of the soil surface and lack secondary carbonates.

GEOGRAPHIC SETTING: The Jumborox soils are on fan remnants. Slopes range from 2 to 15 percent. These soils formed in alluvium derived from granite, granitoid or gneissic rocks. Elevation is 1000 to 1575 meters (3,280 to 5,200 feet). The climate is arid with hot, dry summers and warm, moist winters. The mean annual precipitation is 100 to 175 millimeters (4 to 7 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 the Desertqueen, Morongo and Ironped soils. Desertqueen soils are very shallow and shallow to a paralithic contact and are found in areas where fan aprons cover pediment surfaces. Morongo soils are on fan aprons, are very deep and sandy throughout the particle-size control section. Ironped soils are on fan aprons over pediments, and nearby hills and mountains. They are very shallow and shallow to a paralithic contact, do not have an argillic horizon and are sandy throughout.

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

USE AND VEGETATION: This soil is used for recreation and wildlife habitat. Vegetation is blackbrush, California juniper, creosote bush, Mojave yucca, and joshua tree.

DISTRIBUTION AND EXTENT: Mojave Desert of southeastern California. MLRA 30. These soils are of small 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. Source of name is the Jumbo Rocks area of Joshua Tree National Park.

REMARKS: Diagnostic horizons and features in this pedon include:

Ochric epipedon: from a depth of 0 to 10 centimeters (A1 and A2 horizons)
Argillic horizon: from a depth of 10 to 93 centimeters (Bt1, Bt2 and Bt3 horizons)
Particle size control section: 10 to 60 centimeters (Bt1, Bt2 and upper
part of Bt3 horizons)

ADDITIONAL DATA: NASIS User Pedon ID: 1249720324.

Responsibility for this series was transferred from Davis to Phoenix 9/2015. The last revision to the series was 5/2012. ET

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National Cooperative Soil Survey
U.S.A.