LOCATION TUBORCIO CAEstablished Series
TAXONOMIC CLASS: Fine, mixed, superactive, thermic Ultic Palexerolls
TYPICAL PEDON: Tuborcio sandy loam on a northeast facing hill with 39 percent slope under a cover of blue oaks and annual grasses at an elevation of 2,030 feet (620 meters). When described on 04/26/2006 the soil was moist from 3 to 60 inches (8 to 153 cm). Colors are for dry soils unless otherwise noted.
A1--0 to 3 inches (0 to 8 centimeters); brown (10YR 5/3), sandy loam, dark brown (10YR 3/3), moist; moderate very fine granular structure; soft, very friable, slightly sticky and slightly plastic; many very fine and fine roots; many very fine and fine interstitial pores; 5 percent gravel; neutral (pH 6.6); clear smooth boundary.
A2--3 to 13 inches (8 to 34 centimeters); brown (10YR 5/3), sandy clay loam, dark brown (10YR 3/3), moist; moderate fine and medium subangular blocky structure; slightly hard, friable, moderately sticky and moderately plastic; common fine, medium, and common coarse roots; common very fine and fine tubular pores; 5 percent gravel, 1 percent cobbles; strongly acid (pH 5.2); clear smooth boundary. (Combined thickness of the A horizons is 4 to 18 inches, 10 to 46 centimeters)
Bt1--13 to 24 inches (34 to 60 centimeters); light yellowish brown (10YR 6/4), clay, dark yellowish brown (10YR 4/4), moist; strong medium angular blocky structure; very hard, very firm, very sticky and very plastic; common fine, medium, and coarse roots; common fine and medium tubular pores; few discontinuous slickensides (pedogenic) and common discontinuous faint clay films on surfaces along pores and on all faces of peds; 5 percent gravel; strongly acid (pH 5.1); gradual smooth boundary. (4 to 13 inches, 9 to 34 centimeters thick)
Bt2--24 to 33 inches (60 to 85 centimeters); brownish yellow (10YR 6/6), clay, dark yellowish brown (10YR 4/6), moist; strong medium angular blocky structure; very hard, very firm, very sticky and very plastic; common fine, and medium roots; common fine tubular pores; few discontinuous slickensides (pedogenic) and common discontinuous faint clay films on all faces of peds and on surfaces along pores; 5 percent gravel; strongly acid (pH 5.2); gradual smooth boundary. (4 to 10 inches, 11 to 25 centimeters thick)
Bt3--33 to 49 inches (85 to 125 centimeters); 50 percent very pale brown (10YR 8/3) and 50 percent very pale brown (10YR 7/4), sandy clay, 50 percent very pale brown (10YR 8/3) and 50 percent yellowish brown (10YR 5/6), moist; strong medium angular blocky structure; very hard, very firm, very sticky and very plastic; many discontinuous distinct clay films on all faces of peds and on surfaces along pores; 5 percent gravel; slightly acid (pH 6.1); gradual smooth boundary. (0 to 25 inches, 0 to 63 centimeters thick)
Crt--49 to 60 inches (125 to 153 centimeters); 50 percent very pale brown (10YR 8/3) and 50 percent light yellowish brown (10YR 6/4), weakly cemented granite crushes to sandy clay loam, 50 percent very pale brown (10YR 8/3) and 50 percent yellowish brown (10YR 5/6), moist; massive; very hard, very firm, very sticky and very plastic; few clay films on gravel; 90 percent gravel; slightly acid (pH 6.3).
TYPE LOCATION: San Benito County, California; 600 feet (180 meters) northwest of the west gate to Pinnacles National Monument on Highway 146.; 230 feet north, and 756 feet west of the southeast corner of section 5, T 17S, R 07E; USGS North Chalone Peak, California topographic quadrangle; 36 degrees 28 minutes 26.10 seconds north latitude and 121 degrees 13 minutes 35.80 seconds west longitude; UTM 658879 meters E, 4037979 meters N, zone 10.
RANGE IN CHARACTERISTICS:
Depth to bedrock: more than 60 inches (150 centimeters).
Mean annual soil temperature: 60 to 63 degrees F (16 to 17 degrees C).
Soil moisture control section: dry in all parts from about June 15 to November 15 (150 days), and moist in all parts from about January 15 to May 1 (105 days).
Particle size control section: 45 to 55 percent clay, 5 to 35 percent rock fragments from granite. .
Base saturation by ammonium acetate: 90 to 100 %
A horizon(s):
Hue: 10YR
Value: 4, 5 dry; 2, 3 moist
Chroma: 2, 3 dry; 1, 2, 3 moist
Texture of the fine earth fraction: Loam, sandy loam, coarse sandy
loam, sandy clay loam
Clay content: 8 to 20 percent
Rock fragments: 5 to 20 percent gravel
Reaction: moderately acid to neutral
Base Saturation by sum of cations: 73 to 81 %
Bt horizon(s):
Hue: 10YR, 7.5YR
Value: 4, 5, 6, 7, 8 dry; 2, 3, 4, 5, 8 moist
Chroma: 2, 3, 4, 6 dry; 2, 3, 4, 6 moist
Texture of the fine earth fraction: clay, clay loam, sandy clay
Clay content: 20 to 55 percent
Rock fragments: 5 to 35 percent gravel
Reaction: moderately acid to neutral
Base Saturation by sum of cations: 75 %
Crt horizon(s):
Hue: 10YR
Value: 6, 8 dry; 5, 8 moist
Chroma: 2, 3, 4 dry; 2, 3, 6 moist
Texture of the fine earth fraction: Sandy clay loam
Clay content: 25 to 30 percent
Para Rock fragments: 80 to 90 percent paragravel
Reaction: moderately acid to neutral
COMPETING SERIES: These are the Malibu and Santa Ynez soils. Malibu soils are 20 to 40 inches (50 to 100 centimeters) deep to paralithic material. The Santa Ynez soils have an abrupt boundary between the A2 and B2t horizons, and lack para rock fragments in the C horizon.
GEOGRAPHIC SETTING: Tuborcio soils are on hills. Slopes range from 2 to 50 percent. These soils formed in residuum weathered from granite. Elevation is 950 to 2,400 feet (290 to 735 meters). The climate is characterized by hot, dry summers and cool, moist winters. The mean annual precipitation is 17 to 19 inches (432 to 483 millimeters) and the mean annual air temperature is about 59 to 63 degrees F (15 to 17 degrees C). The frost free season is 190 to 210 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Backdoor and Rimtrail soils. The Backdoor soils are in the fine-loamy particle size family and are on hills under chamise chaparral. The Rimtrail soils are in the fine-loamy particle size family with a Pachic epipedon and are on basin floors under annual grasses.
DRAINAGE AND PERMEABILITY: Well drained, slow permeability, very high runoff. They do not flood or pond.
USE AND VEGETATION: This soil is used for watershed, wildlife habitat and recreation. Vegetation is blue oak with an understory of grasses or chamise chaparral.
DISTRIBUTION AND EXTENT: San Benito and Monterey Counties, California in MLRA 15 -- Central California Coast Range. These soils are of small extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Davis, California
SERIES ESTABLISHED: San Benito County, California, 2006. Source of name: rock formation in Pinnacles National Monument. This series was established based on limited acreage observed within the National Park Service Pinnacles National Monument boundary.
REMARKS:
Diagnostic horizons and features recognized in this pedon are:
Mollic Epipedon: the zone from 0 to 13 inches (0 to 34 centimeters) (A1 and A2 horizons)
Argillic Horizon: the zone from 13 to 33 inches (34 to 85 centimeters) (Bt1 and Bt2 horizons)
ADDITIONAL DATA:
Pedon information for another location:
Pedon Type: range in characteristcs Lab Source ID: NSSL
Pedon Purpose: research site Lab Pedon #: 06N0208