LOCATION LIVERMORE CAEstablished Series
TAXONOMIC CLASS: Loamy-skeletal, mixed, superactive, thermic Typic Haploxerolls
TYPICAL PEDON: Livermore very gravelly coarse sandy loam.
(Colors given are for dry conditions unless otherwise stated.)
Ap1--0 to 4 inches; brown (10YR 5/3) very gravelly coarse sandy loam, dark brown (10YR 3/3) moist; single grained; loose, friable; very porous; slightly acid (pH 6.4); diffuse smooth boundary. (3 to 6 inches thick).
Ap2--4 to 12 inches; dark grayish brown (10YR 4/2) very gravelly coarse sandy loam, very dark grayish brown (10YR 3/2) moist; massive; slightly hard, friable, slightly sticky; porous, many fine and very fine roots; many fine and very fine pores; few cobbles; neutral (pH 6.7); diffuse smooth boundary. (4 to 8 inches thick).
A--12 to 21 inches; dark grayish brown (10YR 4/2) very gravelly coarse sandy loam, very dark grayish brown (10YR 3/2) moist; massive; slightly hard, friable, slightly sticky; abundant fine and very fine roots and pores; few thin discontinuous clay films in pores; few cobbles and stones; neutral (pH 6.8); diffuse smooth boundary. (8 to 12 inches thick).
Bw1--21 to 28 inches; brown (10YR 5/3) very gravelly coarse sandy loam, dark brown (10YR 3/3) moist; massive; slightly hard, friable, slightly sticky; few fine roots; many fine and very fine pores; few thin clay films in pores; few cobbles and stones; neutral (pH 7.0); diffuse, smooth boundary. (5 to 9 inches thick).
Bw2--28 to 34 inches; brown (10YR 5/3) very gravelly coarse sandy loam, dark brown (10YR 4/3) moist; massive; slightly hard, friable, slightly sticky; few fine roots; many fine and very fine pores; very thin nearly continuous clay films in pores; few cobbles and stones; neutral (pH 7.1); diffuse smooth boundary. (4 to 10 inches thick).
C--34 to 60 inches; brown (10YR 5/3) very gravelly coarse sand, dark brown (10YR 4/3) moist; massive; slightly hard, friable; few fine roots; many fine and very fine pores; a small amount of colloid in bridges between sand grains and as stains on sand and gravels; neutral (pH 7.1).
TYPE LOCATION: Alameda County, California; about 3 miles southeast of Livermore at a point 2,000 feet east and 2,600 feet north of the southwest corner of section 23, T. 3 S., R. 2 E., MDB&M. 37 degrees North latitude, 39 minutes, 25 seconds, 121 degrees West longitude, 43 minutes,33 seconds.
RANGE IN CHARACTERISTICS:
The Ap and A horizons have dry colors of 10YR 5/3, 5/2, 4/3, 4/2 and moist colors or 10YR 3/3, 3/2, 2/2. Texture of surface layer ranges from very gravelly coarse sandy loam, very gravelly sandy loam, very gravelly loam, through gravelly loam. Reaction is slightly acid to neutral.
The B horizons have dry colors of 10YR 6/4, 5/4, 5/3; 7.5YR 6/4, 5/4, 4/4 and moist color of 10YR 4/6, 4/4, 4/3, 3/4, 3/3; 7.5YR 4/6, 4/4, 3/4. Texture ranges from very gravelly coarse sandy loam to very gravelly clay loam, inclusive. Reaction is slightly acid to slightly alkaline.
The C horizon has dry colors of 10YR 6/3, 5/4 and moist colors of 10YR 4/4, 4/3, 3/4. Texture ranges from very gravelly loamy coarse sand to very gravelly loam, inclusive. Reactionis slightly acid to slightly alkaline.
COMPETING SERIES: There are no other series in this family.
GEOGRAPHIC SETTING: Livermore soils developed in very gravelly alluvium from sedimentary and metasedimentary rock. The soils occur on low nearly level terraces and alluvial fans. Slopes range from 0 to 9 percent. Livermore soils occur at elevations of 100 to 1600 feet in a dry subhumid, mesothermal climate having a mean annual rainfall of 14 to 22 inches with hot, dry summers and cool, moist winter; an average January temperature of 48 degrees F.; an average July temperature of 71 degrees F.; a mean annual temperature of about 59 degrees F.; and frost free season is 185 to 250 days.
GEOGRAPHICALLY ASSOCIATED SOILS: Livermore soils are geographically associated with Pleasanton, Yolo, Cortina and Positas series and they are similar to Pleasanton, Cortina, and Millrace soils. Pleasanton soils are gravelly and have moderately fine textured B horizons. Cortina soils are very gravelly coarse textured alluvial soils, lacking B horizons. Millrace soils, developed in very gravelly coarse textured alluvium from basalt and andesite, have coarse textured sola but are otherwise similar.
DRAINAGE AND PERMEABILITY: Somewhat excessively drained. Runoff is negligable to low. Permeability is moderately rapid.
USE AND VEGETATION: Mainly cultivated, primarily for vineyards and orchard; native vegetation annual grasses, forbs and scattered oak.
DISTRIBUTION AND EXTENT: Interior and coastal valleys in or adjacent to the Coast Ranges in central California. The Livermore series is of moderate extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Davis, California
SERIES ESTABLISHED: Livermore Area, California, 1910. (Name from area.)
ADDITIONAL DATA: NSSL pedons: S59CA-001-003 (series type location) and S59CA-001-004 (taxadjunct).
REMARKS: Diagnostic horizons and features recognized in this pedon are:
Mollic epipedon: Zone from the surface to a depth of 12 inches. The organic carbon percent drops to 0.50 percent and less below 12 inches.
CEC class: The CEC/clay is above .80 throughout the pedon.
Cambic horizon: Zone from 21 to 34 inches.