LOCATION BURNTFLAT CATentative Series
TAXONOMIC CLASS: Loamy-skeletal, mixed, superactive, thermic Lithic Haploxerepts
TYPICAL PEDON: Burntflat very gravelly sandy loam, on an east-northeast facing, linear to slightly convex, 35 percent slope under manzanita, yucca and juniper at an elevation of 1,490 meters (4,885 feet). (Colors are for dry soil unless otherwise noted.) The surface is covered by approximately 25 percent gravel.
A-- 0 to 13 centimeters, (0 to 5 inches); dark gray (10YR 4/1) very gravelly sandy loam, black (10YR 2/1) moist; moderate fine and medium subangular structure; slightly hard, friable, nonsticky, nonplastic; common fine and medium roots throughout; 40 percent gravel, 5 percent cobbles and 2 percent stones; slightly acid (pH 6.4); clear smooth boundary. (5 to 15 centimeters thick)
Bw-- 13 to 28 centimeters, (5 to 11 inches); light brownish gray (10YR 6/2) very gravelly sandy loam, 50 percent dark yellowish brown (10YR 4/4) and 50 percent very dark grayish brown (10YR 3/2) moist; weak medium subangular blocky structure; slightly hard, friable, nonsticky, nonplastic; common fine roots and medium roots throughout; 50 percent gravel, 5 percent cobbles and 2 percent stones; neutral (pH 6.6); clear wavy boundary. (10 to 25 centimeters thick)
Cr-- 28 to 36 centimeters, (11 to 14 inches); massive; common medium roots throughout; very strongly acid (pH 5.0); gradual irregular boundary.
R-- 36 centimeters, (14 inches); fractured granitoid rock; common medium roots in fractures.
TYPE LOCATION: San Bernardino County, California; 105 meters (350 feet) west and 105 meters (350 feet) north of the SE corner of section 2, T. 1 N., R. 3 W.; 34 degrees, 11 minutes and 51.5 seconds north latitude and 117 degrees, 09 minutes and 4.7 seconds west longitude; Harrison Mountain 7.5 minute quadrangle; UTM 11S 0486059e 3784081n (DTM: NAD83).
RANGE IN CHARACTERISTICS: Soil moisture control section: Usually dry in all parts from late May or early June until late November or early December, and usually moist in some or all parts the rest of the year. The soils have a xeric moisture regime.
Soil temperature: 17 to 19 degrees C. (63 to 66 degrees F.)
Organic matter: 1 to 4 percent
Surface rock fragments: 5 to 30 percent gravel
Control section -
Depth to a paralithic contact: 20 to 30 centimeters
Depth to a lithic contact: 30 to 36 centimeters
Rock fragments: 35 to 60 percent
Clay content: 6 to 15 percent
A horizon
Value: 3 or 4 dry, and 2 or 3 moist
Chroma: 1 or 2, dry or moist
Texture of the fine earth: sandy loam or loam
Clay content: 6 to 15 percent
Rock fragments: 35 to 55 percent gravel, cobbles and stones
Reaction: slightly acid or neutral
Bw horizon
Value: 3 or 4 moist
Chroma: 2 to 4 moist
Texture of the fine earth: sandy loam or loam
Clay content: 6 to 15 percent
Rock fragments: 40 to 60 percent gravel, cobbles and stones
Reaction: slightly acid or neutral
COMPETING SERIES: This is the Dedrick series. Dedrick soils are formed from metavolcanic rocks or mica schist. Mean annual precipitation is about 1,143 millimeters (45 inches).
GEOGRAPHIC SETTING: Burntflat soils are on mountain slopes. Slopes range from 30 to 80 percent. These soils formed in residuum and colluvium from granitoid sources. Elevations range from 1,220 to 1,525 meters (4,000 to 5,000 feet). The climate is subhumid mesothermal with warm, dry summers and cool, moist winters with some snow. The mean annual precipitation is 381 to 533 millimeters (15 to 21 inches) and the mean annual air temperature is 16 to 18 degrees C. (60 to 64 degrees F.) The frost-free season is 300 to 340 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Marielouise (T), Runningsprings (T) and Skyland (T) soils. None of these soils have a lithic contact within 36 centimeters (14 inches). Marielouise soils are on alluvial fans. Marielouise and Runningsprings have mollic epipedons. In addition, Runningsprings soils have a coarse-loamy particle-size control section and a mesic soil temperature regime. Marielouise and Skyland soils do not have a paralithic or lithic contact within 100 centimeters (40 inches).
DRAINAGE AND PERMEABILITY: Well-drained; medium runoff; moderately rapid permeability.
USE AND VEGETATION: Burntflat soils are used for recreation, watershed and wildlife habitat. Some areas are used for homesites. The present vegetation is mainly manzanita, juniper and yucca.
DISTRIBUTION AND EXTENT: Inland mountain ranges of San Bernardino, Riverside and San Diego counties, southern California. MLRA 20. These soils are of small extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Davis, California.
SERIES PROPOSED: San Bernardino County, California, San Bernardino National Forest, Private Land Soil Survey Update, 2004. The name is from a location in the soil survey area.
REMARKS: Diagnostic horizons and features recognized in the profile are:
1. Ochric epipedon: 0 to 13 centimeters (A horizon)
2. Cambic horizon: 13 to 28 centimeters (Bw horizon)
3. Paralithic contact: 28 to 36 centimeters (Cr horizon)
4. Lithic contact: the zone beginning at 36 centimeters (R horizon)
5. Particle-size control section: 0 to 28 centimeters (A and Bw horizons)