LOCATION TOGASARA CAEstablished Series
TAXONOMIC CLASS: Loamy-skeletal, mixed, superactive, thermic Typic Argixerolls
TYPICAL PEDON: Togasara gravelly sandy loam, on a northeast facing 16 percent slope under a cover of annual grasses and forbs at an elevation of 367 feet. When described on February 6, 2008, the soil was moist throughout. (Colors are for dry soil unless otherwise noted).
A--0 to 3 inches, (0 to 8 cm); brown (10YR 4/3) broken face gravelly sandy loam, very dark grayish brown (10YR 3/2) broken face moist; 17 percent clay; moderate medium subangular blocky and moderate fine granular structure; slightly hard, very friable, slightly sticky, slightly plastic; many very fine roots; many very fine interstitial pores; 15 percent subrounded indurated 2 to 75 millimeter mixed rock fragments; slightly acid, pH 6.4 by pH meter 1:1 water; clear smooth boundary.
ABt--3 to 7 inches, (8 to 19 cm); brown (10YR 4/3) broken face gravelly sandy clay loam, dark brown (10YR 3/3) broken face moist; 23 percent clay; moderate medium subangular blocky structure; slightly hard, very friable, moderately sticky, moderately plastic; many very fine roots; many very fine interstitial pores; 40 percent clay films on all faces of peds; 15 percent subrounded indurated 2 to 75 millimeter mixed rock fragments; slightly acid, pH 6.3 by pH meter 1:1 water; abrupt smooth boundary.
Bt1--7 to 16 inches, (19 to 41 cm); brown (7.5YR 5/4) broken face very gravelly sandy clay loam, brown (7.5YR 4/4) broken face moist; 25 percent clay; strong medium subangular blocky structure; slightly hard, friable, moderately sticky, moderately plastic; common very fine roots; many very fine interstitial pores; 50 percent clay films on all faces of peds; 50 percent subrounded indurated 2 to 75 millimeter mixed rock fragments; slightly acid, pH 6.3 by pH meter 1:1 water; gradual smooth boundary.
Bt2--16 to 25 inches, (41 to 63 cm); light brown (7.5YR 6/4) broken face very gravelly sandy clay loam, brown (7.5YR 5/4) broken face moist; 26 percent clay; strong fine subangular blocky structure; hard, friable, moderately sticky, moderately plastic; few very fine roots; many very fine interstitial pores; 60 percent clay films on all faces of peds; 55 percent subrounded indurated 2 to 75 millimeter mixed rock fragments; slightly acid, pH 6.4 by pH meter 1:1 water; gradual smooth boundary.
Bt3--25 to 35 inches, (63 to 90 cm); brown (7.5YR 5/4) broken face very gravelly sandy clay loam, brown (7.5YR 4/4) broken face moist; 25 percent clay; moderate fine subangular blocky structure; slightly hard, friable, moderately sticky, moderately plastic; many very fine interstitial pores; 60 percent clay films on all faces of peds; 55 percent subrounded indurated 2 to 75 millimeter mixed rock fragments; neutral, pH 6.7 by pH meter 1:1 water; clear smooth boundary.
BC1--35 to 48 inches, (90 to 123 cm); brownish yellow (10YR 6/6) broken face very gravelly sandy clay loam, dark yellowish brown (10YR 4/6) broken face moist; 20 percent clay; weak fine subangular blocky structure; slightly hard, friable, slightly sticky, moderately plastic; many very fine interstitial pores; 10 percent clay films on all faces of peds; 5 percent subrounded indurated 75 to 254 millimeter mixed rock fragments and 55 percent subrounded indurated 2 to 75 millimeter mixed rock fragments; neutral, pH 6.7 by pH meter 1:1 water; abrupt smooth boundary.
BC2--48 to 60 inches, (123 to 153 cm); light yellowish brown (10YR 6/4) broken face very gravelly sandy loam, yellowish brown (10YR 5/4) broken face moist; 18 percent clay; massive; soft, friable, slightly sticky, slightly plastic; many very fine interstitial pores; 5 percent subrounded indurated 75 to 254 millimeter mixed rock fragments and 50 percent subrounded indurated 2 to 75 millimeter mixed rock fragments; neutral, pH 6.8 by pH meter 1:1 water.
TYPE LOCATION: Santa Clara County, California, Rancho San Antonio Open Space, Los Altos, west of main parking across creek and south on ridge, on north east steep slope., in an unsectionalized area of Township 7s, Range 2w, 4132046 UTM Northing, 580795 UTM Easting, Zone 10, NAD83 - U.S.G.S Quad: Cupertino, California.
RANGE IN CHARACTERISTICS: The mean annual soil temperature is 60 to 62 degrees F. The soil moisture control section is dry in all parts from about May 1 to November 1 (about 180 days). The particle size control section averages 25 to 35 percent clay, and 35 to 55 percent rock fragments, mostly gravel in size. Scattered pararock fragments of highly weathered sandstone occur randomly throughout the soil profile. The soil is not calcareous. Organic matter ranges from 1 to 2 percent to a depth of 19 centimeters. Rock fragments on the surface range from 0 to 5 percent are gravel in size.
The A and ABt horizons dry color is 10YR 6/3, 5/3, 4/3 or 3/3. Moist color is 10YR 4/3, 3/3, 3/2 or 2/2. Texture is sandy loam, sandy clay loam or clay loam or their gravelly equivalents. Clay content ranges from 12 to 24 percent. Rock fragments range from 5 to 20 percent and are gravel in size. Reaction ranges from 6.1 to 7.8.
The Bt horizon dry color is 10YR 5/6, 5/4, 4/4, 4/3; 7.5YR 6/4 or 5/4. Moist color is 10YR 3/6, 3/4; 7.5YR 5/4, 4/4 or 3/3. Texture is gravelly and very gravelly sandy clay loam or gravelly and very gravelly clay loam. Clay content ranges from 23 to 35 percent. Rock fragments range from 15 to 55 percent and are gravel in size. Reaction ranges from 6.1 to 7.8.
The BC horizon dry color is 10YR 6/6, 6/4, 5/6, 5/4, 4/4; 2.5Y 7/4 or 6/4. Moist color is 10YR 5/4, 4/6, 3/4; 2.5Y 6/4 or 5/4. Texture is gravelly or very gravelly sandy loam, or gravelly or very gravelly sandy clay loam. Clay content ranges from 15 to 28 percent. Rock fragments range from 25 to 55 percent and are gravel in size with 0 to 5 percent cobbles. Reaction ranges from 6.6 to 7.3.
COMPETING SERIES: This is the Brecken series. Brecken soils are mapped in the southern part of MLRA 17 and have climate bordering on aridic with 7 to 10 inches of precipitation. The difference between mean winter and mean summer temperatures is more than 30 degrees F. Brecken soils have chromas of 1 or 2 in the A horizon.
GEOGRAPHIC SETTING: Togasara soils are on hills of terraces. Slopes are 2 to 30 percent. These soils formed in old alluvium from mixed rock sources. Elevation is 300 to 500 feet. Mean annual precipitation is 18 to 22 inches. The mean annual temperature is 60 to 62 degrees F. The difference between mean winter and mean summer temperatures is between 18 and 20 degrees F. Temperatures are moderated throughout the year by air flowing from the San Francisco Bay. Frost free season is 275 to 325 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Montavista soils. The Montavista soils have fine textured control sections.
DRAINAGE AND PERMEABILITY: Well drained; moderately slow permeability.
USE AND VEGETATION: This soil is used for urban development and recreation. Vegetation is annual grasses and forbs.
DISTRIBUTION AND EXTENT: The soils are inextensive and are mapped in northern Santa Clara County. Major Land Resource Area: 15 -- Central California Coast Range
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Davis, California
SERIES ESTABLISHED: Santa Clara County, California 2009. Source of coined name from the small town of Saratoga.
REMARKS:
Particle Size Control Section for this pedon: 7 to 27 in. (19 to 69 cm)
Diagnostic horizons and features recognized in this pedon are:
Argillic Horizon: 7 to 35 in. (19 to 90 cm)
The soil moisture control section is dry in all parts from about May 1 to November 1 (about 180 days).
ADDITIONAL DATA:
NASIS SITE and PEDON ID: 08ca085641107