LOCATION HANGERONE CAEstablished Series
TAXONOMIC CLASS: Fine, smectitic, thermic Cumulic Vertic Endoaquolls
TYPICAL PEDON: Hangerone clay, 0 to 2 percent slopes, on an east facing 2 percent slope under a cover of turf grass at an elevation of 30 feet. When described, the soil was moist throughout. (Colors are for dry soil unless otherwise noted).
A1--0 to 9 inches, (0 to 24 cm); dark gray (10YR 4/1) broken face clay, very dark gray (10YR 3/1) broken face moist; 41 percent clay; moderate coarse subangular blocky structure; very hard, very firm, moderately sticky, moderately plastic; common medium roots and common very fine roots; common fine irregular pores; 2 percent subrounded strongly cemented 2 to 75 millimeter mixed rock fragments; violent effervescence, by HCl, 1 normal; moderately alkaline, pH 8.3 by pH meter 1:1 water; abrupt smooth boundary. Upper 1 centimeter of horizon is an Oi layer.
A2--9 to 17 inches, (24 to 42 cm); dark gray (10YR 4/1) broken face clay, very dark gray (10YR 3/1) broken face moist; 50 percent clay; moderate coarse subangular blocky and moderate medium subangular blocky structure; very hard, very firm, moderately sticky, moderately plastic; common medium roots and common very fine roots; common fine irregular pores; 1 percent subrounded strongly cemented 2 to 75 millimeter mixed rock fragments; violent effervescence, by HCl, 1 normal; moderately alkaline, pH 8.3 by pH meter 1:1 water; clear smooth boundary. (Combined thickness of the A horizon is 10 to 50 centimeters thick)
Bw--17 to 27 inches, (42 to 68 cm); dark gray (10YR 4/1) broken face clay, very dark gray (10YR 3/1) broken face moist; 49 percent clay; moderate coarse angular blocky structure; extremely hard, extremely firm, very sticky, very plastic; common medium roots; few fine irregular pores; 65 percent distinct dark gray (10YR 4/1), dry, pressure faces on vertical faces of peds; violent effervescence, by HCl, 1 normal; moderately alkaline, pH 8.4 by pH meter 1:1 water; abrupt wavy boundary. (0 to 85 centimeters thick)
Bk--27 to 35 inches, (68 to 88 cm); gray (2.5Y 6/1) broken face clay, grayish brown (2.5Y 5/2) broken face moist; 43 percent clay; moderate coarse angular blocky and moderate medium angular blocky structure; hard, firm, very sticky, very plastic; few very fine irregular pores; 20 percent distinct white (10YR 8/1), dry, carbonate coats on all faces of peds and 65 percent distinct gray (2.5Y 6/1), dry, pressure faces on vertical faces of peds; 5 percent fine prominent light brown (7.5YR 6/4), dry, iron-manganese masses in matrix; violent effervescence, by HCl, 1 normal; strongly alkaline, pH 8.6 by pH meter 1:1 water; clear smooth boundary. (0 to 48 centimeters thick)
Ck--35 to 45 inches, (88 to 115 cm); light gray (2.5Y 7/1) broken face clay loam, grayish brown (2.5Y 5/2) broken face moist; 33 percent clay; moderate coarse angular blocky and moderate medium angular blocky structure; hard, firm, very sticky, very plastic; few very fine irregular pores; 20 percent distinct white (10YR 8/1), dry, carbonate coats on all faces of peds; 5 percent fine prominent light brown (7.5YR 6/4), dry, iron-manganese masses in matrix; violent effervescence, by HCl, 1 normal; strongly alkaline, pH 8.5 by pH meter 1:1 water; abrupt smooth boundary. (0 to 55 centimeters thick)
C--45 to 72 inches, (115 to 183 cm); light gray (2.5Y 7/2) broken face very gravelly loam, grayish brown (2.5Y 5/2) broken face moist; 24 percent clay; weak coarse granular and weak medium granular structure; moderately hard, friable, nonsticky, nonplastic; many very fine irregular pores; 30 percent subrounded strongly cemented 2 to 75 millimeter mixed rock fragments; violent effervescence, by HCl, 1 normal; strongly alkaline, pH 8.6 by pH meter 1:1 water; abrupt smooth boundary. (0 to 55 centimeters thick)
2Ab--72 to 89 inches, (183 to 225 cm); dark gray (2.5Y 4/1) broken face clay, black (2.5Y 2.5/1) broken face moist; 48 percent clay; moderate coarse subangular blocky structure; hard, firm, moderately sticky, moderately plastic; common very fine irregular pores; violent effervescence, by HCl, 1 normal; moderately alkaline, pH 8.2 by pH meter 1:1 water.
TYPE LOCATION: Santa Clara County, City of Mountain View, Monta Loma Park, west side of park, west of path, south of picnic area., in a non sectionized area, Township 6S, Range 2W, UTM Zone 10; Northing 4140507, Easting 579758, NAD83. U.S.G.S Quad: Mountain View.
RANGE IN CHARACTERISTICS:
Depth to the calcic horizon is 60 to 100 centimeters. These soils have been drained by historic over drafting of groundwater in the Santa Clara valley, and flooding has been controlled by dams and channelization of streams. The mean annual soil temperature is 60 to 62 degrees F. The soil moisture control section is dry in all parts from about June 1 to October 15 (about 135 days). The particle size control section averages 35 to 60 percent clay. Mineralogy is smectitic. The soil is calcareous throughout with slight to violent effervescence. Organic matter ranges from 1 to 4 percent to a depth of 24 centimeters. Surface-initiated reversible cracks 1 to 4 centimeters wide extend to a depth of 25 centimeters from June to October when the soils are not irrigated. Slickensides are not evident in the soil profile but pressure faces occur below the A horizon and in the upper calcic horizon. A fluctuating apparent water table may occur in a few areas at depths of 120 to 160 centimeters from December through April.
The A horizon dry color is 10YR 4/1, 3/1, 2/2, 2/1 or 2.5Y 2.5/1. Moist color is 10YR 2/2, 2/1 or 2.5Y 3/1, 2.5/1. Texture is clay, clay loam or silty clay loam. Clay content ranges from 27 to 40 percent. Rock fragments range from 0 to 5 and are rounded and gravel in size. Reaction ranges from 7.3 to 8.4.
The Bw horizon dry color is 10YR 4/1, 3/1 or 2.5Y 4/1. Moist color is 10YR 3/1, 2/1 or 2.5Y 3/1, 2.5/1. Texture is clay loam, silty clay loam, silty clay and clay. Clay content ranges from 35 to 55 percent. Rock fragments range from 0 to 10 percent, are rounded and are gravel in size. Reaction ranges from 7.3 to 8.4.
The Bk horizon dry color is 10YR 5/1, 4/1, 3/1 or 2.5Y 8/1, 7/2, 7/1, 6/1, 4/1. Moist color is 10YR 4/1, 3/1, 2/1 or 2.5Y 7/2, 5/3, 5/2, 2.5/1. Texture is clay loam, silty clay or clay. Clay content ranges from 35 to 55 percent. Carbonate content ranges from 10 to 25 percent. Rock fragments range from 0 to 10 percent, are rounded and are gravel in size. Reaction ranges from 7.3 to 8.6.
The Ck horizon, if present, has dry color is 10YR 7/3, 7/1, 6/3, 6/1, 5/1 or 2.5Y 7/3, 7/1, 5/3. Moist color is 10YR 5/2, 4/1 or 2.5Y 5/3, 5/2, 5/1. Texture is sandy clay loam, clay loam, silty clay or clay. Clay content ranges from 35 to 45 percent. Carbonate content ranges from 10 to 25 percent. Rock fragments range from 0 to 10 percent, are rounded and are gravel in size. Reaction ranges from 7.8 to 8.6.
The C and 2Ab horizons, if present, have dry color of 10YR 7/3 or 2.5Y 7/3, 7/1. Moist color is 2.5Y 5/4, 5/3, 5/2. Texture is very gravelly loam, silt loam, sandy clay loam or clay. Clay content ranges from 9 to 25 percent. Rock fragments range from 0 to 50 and are rounded and gravel in size. Reaction ranges from 7.8 to 8.6.
COMPETING SERIES: There are no other series in this family. The Sunnyvale series are Calciaquolls that lack B horizons and have calcic horizons whose upper boundary is within 40 centimeters of the surface.
GEOGRAPHIC SETTING: Hangerone(T) soils are in basins. Slopes are 0 to 2 percent. These soils formed in fine textured alluvium weathered from mixed rock sources. Elevation is 0 to 219 feet, Mean annual precipitation is 14 to 16 inches. The mean annual temperature is 60 to 62 degrees F. Frost free season is 275 to 325 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Embarcadero(T) soils. The Embarcadero(T) soils have natric horizons.
DRAINAGE AND PERMEABILITY: poorly drained; slow permeability. The soils are not flooded due to upstream dams and channelization. Most areas are artificially drained with water tables now below 1.5 meters. A fluctuating apparent water table may occur in a few areas at depths of 120 to 160 centimeters from December through April.
USE AND VEGETATION: This soil is used for urban development. Vegetation is ornamental plants.
DISTRIBUTION AND EXTENT: The soils are extensive and are mapped in Santa Clara County, Major Land Resource Area: 14 -- Central California Coastal Valleys
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Davis, California
SERIES ESTABLISHED: Santa Clara County, California, 2009. Source of name from historical aircraft hanger One at Moffett Field. MLRA 14.
REMARKS:
Particle Size Control Section for this pedon: 10 to 40 in. (25 to 100 cm)
Diagnostic horizons and features recognized in this pedon are:
Calcic Horizon: 27 to 45 in. (68 to 115 cm)
Aquolls suborder in artificial drainage environment: The lower part of the mollic epipedon extends to 68 centimeters with chromas of 1. Redox concentrations were not readily observable from auger holes but are assumed to occur. The high carbonate environment of the lower Mollic epipedon may be masking the redox. Historically these soils were quite wet seasonally with scattered artesian wells.
With artificial drainage, the soil moisture control section is dry in all parts from about May 1 to November 1 (about 180 days).
ADDITIONAL DATA: NASIS Pedon and NSSL ID: 05ca085641225
NSSL sample number: 07N0671