LOCATION UMBERCI                 CA

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

UMBERCI SERIES

The Umberci series consists of very shallow to bedrock, somewhat excessively drained soils that formed in residuum and colluvium from limestone and dolomite. Umberci soils are on mountains and hills. Slopes range from 30 to 75 percent. The mean annual precipitation is about 140 millimeters and the mean annual temperature is about 16.5 degrees C.

TAXONOMIC CLASS: Loamy-skeletal, carbonatic, thermic Lithic Torriorthents

TYPICAL PEDON: Umberci gravelly sandy loam, on a north facing 50 percent slope under a cover of shrubby rangeland at an elevation of 1267 m (4158 feet). (Colors are for dry soil unless otherwise noted. When described on October 27, 2005 the soil was moist throughout.) The surface is covered by 74 percent gravel, 15 percent cobbles, 5 percent stones, and 1 percent boulders.

A--0 to 1 centimeters (0 to 0.5 inch); pale brown (10YR 6/3) gravelly sandy loam, dark yellowish brown (10YR 4/4) moist; weak thin platy structure; soft, very friable, nonsticky and nonplastic; common very fine roots throughout; few very fine tubular pores; 35 percent gravel and 1 percent cobbles and 1 percent stones; strongly effervescent; moderately alkaline (pH 8.2); diffuse smooth boundary. (1 to 4 centimeters thick)

Bkq--1 to 13 centimeters (0.5 to 5 inches); pale brown (10YR 6/3) very gravelly fine sandy loam, dark yellowish brown (10YR 4/4) moist; massive; soft, very friable, nonsticky and nonplastic; common very fine and fine roots throughout; few very fine vesicular pores; 3 percent fine, distinct, irregular, very weakly cemented, very pale brown (10YR 7/3), dry, carbonate masses with clear boundaries on bottom of rock fragments; 3 percent, distinct, very pale brown (10YR 7/3) silica on the bottom of rock fragments; 45 percent gravel and 1 percent cobbles; violently effervescent (65 percent calcium carbonate equivalent); moderately alkaline (pH 8.4); abrupt irregular boundary. (10 to 22 centimeters thick)

R--13 centimeters (5 inches); 1 to 5 centimeters thick highly fractured limestone with few fine roots (fractures are greater than 10 centimeters apart) above indurated limestone bedrock.
TYPE LOCATION: San Bernardino County, California; approximately 9.1 kilometers east and 2 kilometers north of Primm, Nevada; 260 meters north and 550 meters west of the southeast corner of Sec. 5, T. 17 N., R. 14 E.; USGS Ivanpah Lake, California 7.5 minute topographic quadrangle; 35 degrees, 37 minutes, 21 seconds N. and 115 degrees, 29 minutes, 29 seconds W., UTM 11S 3943125n 636618e, NAD 83.
RANGE IN CHARACTERISTICS:

Soil moisture - Usually dry, moist in some part for short periods during winter and early spring and for 10 to 20 days cumulative between July to September following summer convection storms; Typic-aridic moisture regime.

Soil temperature 15 to 22 degrees C (59 to 72 degrees F).
Depth to lithic contact 12 to 25 centimeters (5 to 10 inches).

Control Section

Percent clay: 8 to 14 percent.
Rock fragments: Averages 35 to 55 percent, mainly gravel.
Calcium carbonate equivalent: averages 50 to 65 percent in the less than 2 millimeter fraction and 55 to 70 percent in the less than 20 millimeter fraction.


A horizon
Value: 6 dry, 3 to 5 moist.
Chroma: 3 or 4.
Texture of the fine earth fraction: sandy loam or fine sandy loam.
Rock fragments: averages 20 to 50 percent, mainly gravel.

Bkq or Bk horizon
Value: 6 or 7 dry, 3 to 5 moist.
Texture of the fine earth fraction: sandy loam or fine sandy loam.
Rock fragments: Averages 35 to 50 percent, mainly gravel.
Note: Bk horizons are not thick enough or do not have enough of a difference in calcium carbonate equivalence to be calcic horizons.

COMPETING SERIES: These are the Birdspring (NV), Dozer(NM), Mariscal(TX), Saguaro(AZ), and St. Thomas (NV) soils. Birdspring and St. Thomas soils have 50 to 70 percent rock fragments in the particle size control section and Birdspring soils are moist for less than 10 to 20 days cumulative following summer convection storms. Dozer soils have 18 to 35 percent clay in the particle size control section and have a climate typical of the Chihuahuan desert. Mariscal soils are channery or flaggy. Saguaro soils are moist in some part of the particle size control section for more than 20 days cumulative from June through August and have a climate typical of the Sonoran desert.

GEOGRAPHIC SETTING: Umberci soils are on hills and mountains. Slopes are 30 to 75 percent. These soils formed in residuum and colluvium weathered from limestone and dolomite. Elevation is 840 to 1605 meters (2800 to 5250 feet). Mean annual precipitation is 100 to 175 millimeters (4 to 7 inches). The mean annual temperature is 13 to 20 degrees C (55 to 68 degrees F). Frost free season is 210 to 320 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Colosseum soils. Colosseum soils are in drainageways and are very deep.

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

USE AND VEGETATION: Rangeland and wildlife habitat. Vegetation is mainly Nevada jointfir, snakeweed, Utah mortonia, shadscale, and big galleta.

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

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

SERIES ESTABLISHED: San Bernardino County, Clark Mountain Grazing Allotment, part of the Mojave Desert, northeast part, California, 2007. The name is from the nearby Umberci mine.

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

1. Ochric Epipedon: 0 to 1 centimeters (0 to 0.5 inches). (A horizon)
2. Particle Size Control Section for this pedon: 0 to 13 centimeters (0 to 5 inches). (A and Bk horizons)
3. Lithic contact: 13 centimeters (5 inches). (R horizon)

Responsibility for this series was transferred from Davis to Phoenix 12/2015. The last revision to the series was 5/2007. ET

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National Cooperative Soil Survey
U.S.A.