LOCATION PIONEERTOWN CA
Established Series
Rev: CAH/ET
12/2015
PIONEERTOWN SERIES
The Pioneertown series consists of very shallow and shallow soils, excessively drained soils that formed in colluvium over residuum from granite. The Pioneertown soils are on backslopes of hills. Slopes range from 15 to 60 percent. The mean annual precipitation is 175 millimeters (7 inches) and the mean annual air temperature is 15 degrees C (59 degrees F).
TAXONOMIC CLASS: Mixed, thermic Lithic Torripsamments
TYPICAL PEDON: Pioneertown gravelly coarse sand, on a 30 percent slope at an elevation of 1251 meters. When described the soil was dry throughout. (Colors are for dry soils unless otherwise noted.) The surface is covered by 65 percent fine gravel, 10 percent medium and coarse gravel, 3 percent cobbles, 1 percent stones and 1 percent boulders.
A -- 0 to 4 centimeters (0 to 2 inches); brown (10YR 5/3) gravelly coarse sand, dark brown (10YR 3/3) moist; weak fine subangular blocky parting to single grain; soft, very friable, nonsticky and nonplastic; common very fine roots throughout; common very fine interstitial pores; 18 percent fine gravel and 2 percent medium and coarse gravel; slightly alkaline (pH 7.4); clear smooth boundary. (3 to 10 centimeters thick)
Bw -- 4 to 15 centimeters (2 to 6 inches); brown (10YR 5/3) gravelly sand, dark brown (10YR3/3) moist; weak fine and medium subangular blocky structure; soft, very friable, nonsticky and nonplastic; common very fine roots throughout; common fine and very fine tubular pores; 27 percent fine gravel and 3 percent medium and coarse gravel; neutral (pH 7.2); abrupt wavy boundary. (0 to 20 centimeters thick)
Rt -- 15 to 40 centimeters (6 to 12 inches); indurated granitic bedrock; common very fine roots in cracks; 2 percent distinct brown (10YR 4/3), clay films on top surface of horizon.
TYPE LOCATION: San Bernardino County, California; 620 meters south of Skyline Ranch Road in the Sawtooth Mountains; 100 meters south and 200 meters west of the northeast corner of sec. 29, T. 1 N., R. 5 E., San Bernardino Base and Meridian; USGS Yucca Valley North, CA 7.5 minute topographic quadrangle; 34 degrees, 8 minutes, 55 seconds north latitude and 116 degrees, 28 minutes, 40 seconds west longitude; UTM 11S 548155e, 3378759n (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.
Surface rock fragments: ranges from 80 to 95 percent, dominantly fine gravel.
Control section-
Rock fragments: 15 to 34 percent, dominantly fine gravel.
Clay content: 3 to 8 percent.
Organic matter: 0.25 to 1 percent.
Depth to lithic contact: 4 to 36 centimeters (2 to 14 inches).
Effervescence: noneffervescent throughout.
A horizon
Hue: 10YR or 2.5Y.
Value: 3 or 4, moist.
Chroma: 3 or 4 dry, and 2 to 4 moist.
Texture of the fine earth: coarse sand, sand or loamy sand.
Clay content: 2 to 6 percent.
Rock fragments: 15 to 34 percent.
Reaction: neutral to slightly alkaline.
Bw horizon (when present)
Value: 5 or 6 dry, 3 or 4 moist.
Chroma: 3 or 4, dry or moist.
Texture of the fine earth: sand or loamy sand.
Clay content: 3 to 5 percent.
Rock fragments: 10 to 30 percent.
C horizon (when present)
Value: 5 or 6 dry.
Chroma: 3 or 4, dry or moist.
Texture of the fine earth: coarse sand or loamy sand.
Clay content: 2 to 8 percent.
Rock fragments: 10 to 34 percent, 10 to 34 gravel and 0 to 5 percent cobbles.
Note: some pedons have either a thin layer of gravel above the R horizon or a thin veneer of Cr material above the hard bedrock.
COMPETING SERIES: These are the
Schiefflin (AZ),
Stranger (CA), and
Toquerville (UT) series. Schiefflin soils receive greater than 300 millimeters of precipatation and have an ustic-aridic soil moisture regime, typical of the Sonoran Desert. Stranger soils have a typic-aridic soil moisture regime and a mean annual soil temperature of 19 to 22 degrees C. Toquerville soils are formed in eolian material derived from sandstone, are 36 to 50 centimeters to hard sandstone bedrock, have hues of 2.5YR to 5YR and have 0 to 15 percent rock fragments.
GEOGRAPHIC SETTING: The Pioneertown soils are on backslopes of hills. Slopes range from 15 to 60 percent. These soils formed in colluvium over residuum weathered from granite. Elevation is 1097 to 1768 meters (3,600 to 5,800 feet). The climate is arid bordering on xeric with hot, dry summers and cool, moist winters. The mean annual precipitation is 125 to 250 millimeters (5 to 10 inches) and the mean annual air temperature is 13 to 17 degrees C (55 to 62.5 degrees F). The frost free season is 210 to 270 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are mainly miscellaneous areas of rock outcrop and
Pinecity soils. Pinecity soils are very shallow and shallow to weathered granitic bedrock and are found on lower sideslopes and footslopes where water collects.
DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY: Excessively drained; high saturated hydraulic conductivity above the bedrock and low saturated hydraulic conductivity within the bedrock.
USE AND VEGETATION: Pioneertown soils are used for wildlife habitat and recreation. Vegetation is mainly Muller's oak, mountain mahogany, pinyon pine with some California juniper and blackbrush.
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. The name is from nearby Pioneertown, a small town north of Yucca Valley near 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)
Lithic contact - the zone beginning at 15 centimeters. (Rt horizon)
Particle size control section - from a depth of 0 to 15 centimeters. (A and Bw horizons)
ADDITIONAL DATA: NASIS User Pedon ID: 1249813818.
National Cooperative Soil Survey
U.S.A.