LOCATION SEPULVEDA               CA

Established Series
Rev. RLR/GML/RLR
03/2017

SEPULVEDA SERIES

The Sepulveda series are well drained soils that formed in human-transported material (HTM) found on alluvial fan remnants that originate from sedimentary sources. Sepulveda soils are on cut/fill and localized raised land in areas that have been graded. Slopes range from 0 to 15 percent. The mean annual precipitation is about 356 mm and the mean annual air temperature is about 17 degrees C.

TAXONOMIC CLASS: Fine-loamy, spolic, mixed, superactive, calcareous, thermic Typic Xerorthents

TYPICAL PEDON: Sepulveda clay loam - urban environment. (Colors are for moist soils unless otherwise noted.)

^Au--0 to 24 cm; very dark brown (10YR 2/2) clay loam, very dark brown (10YR 2/2) dry; moderate very coarse subangular blocky structure parting to moderate coarse subangular blocky structure; firm, extremely hard, moderately sticky and moderately plastic; common fine and very fine roots; common fine and very fine irregular pores; 1 percent gravel; 2 percent artifacts; very slightly effervescent; neutral (pH 7.2); clear wavy boundary. (7 to 35 cm thick)

^C1--24 to 55 cm; brown (7.5YR 4/2) sandy clay loam, 10 percent very dark grayish brown (10YR 3/2) and brown (7.5YR 4/4) dry; moderate medium subangular blocky structure; firm, extremely hard, very sticky and very plastic; common fine and very fine roots; common very fine irregular pores; many prominent clay films on all faces of peds; common coarse irregular white (10YR 8/1) calcium carbonate masses; very slightly effervescent; slightly alkaline (pH 7.4); few pockets of strong brown (7.5YR 4/6) mixed into matrix; calcium carbonate masses and clay films are remnant from source material; clear wavy boundary.

^C2--55 to 114 cm; 15 percent dark yellowish brown (10YR 4/6) and dark yellowish brown(10YR 4/4) sandy clay loam, 2 percent dark grayish brown (10YR 4/2) and dark yellowish brown (10YR 4/4) dry; massive; friable, moderately sticky and moderately plastic; common very fine irregular pores; many distinct clay films on faces of peds; common coarse irregular white (10YR 8/1) calcium carbonate masses; very slightly effervescent; slightly alkaline (pH 7.8); calcium carbonate masses and clay films are remnant from source materials; gradual wavy boundary.

^C3--114 to 188 cm; yellowish brown (10YR 5/4) sandy clay loam; massive; friable, moderately sticky and moderately plastic; common very fine irregular pores; common coarse irregular white (10YR 8/1) calcium carbonate masses; very slightly effervescent; slightly alkaline (pH 7.8); calcium carbonate masses are remnant from source materials; clear wavy boundary.

^C4--188 to 200 cm; yellowish brown (10YR 5/4) fine sandy loam; massive; friable, slightly sticky and slightly plastic; few fine faint irregular yellowish brown (10YR 5/6) iron-manganese masses in matrix surrounding redox depletions and common medium distinct irregular grayish brown (10YR 5/2) iron depletions in the matrix; slightly alkaline (pH 7.8).

TYPE LOCATION: Los Angeles County, California, Cheviot Hills Recreation Center Park behind baseball field area
34 degrees, 2 minutes, 44 seconds North latitude and 118 degrees, 24 minutes, 44 seconds West longitude, WGS84 - U.S.G.S Quad: Beverly Hills.

RANGE IN CHARACTERISTICS:

Soil moisture: moist below a depth of about 30 cm some time from October to December and remains moist in some part between depths of about 30 to 90 cm until April or May.
Mean annual soil temperature: 18 to 20 degrees C.

Human-transported materials: typically greater than 100 cm thick, often greater than 200 cm thick.
Rock fragment content: 0 to 15 percent subrounded or mechanically abraded (broken) fragments.
Reaction: neutral to moderately alkaline.
Artifacts: 0 to 15 percent construction debris (concrete, bricks, asphalt, glass).

^A(u) horizon
Moist color: hue of 10YR or 7.5YR, value of 2 to 4, chroma of 2 to 4.
Texture: clay loam, loam, silt loam or clay.
Rock fragments: 0 to 10 percent.
Artifacts: 0 to 5 percent construction debris (concrete, bricks, asphalt, glass).
Bulk density: typically 1.5 to 1.7 from compaction.


^C(u) horizon
Moist color: hue of 10YR or 7.5YR, value of 3 to 6, chroma of 2 to 6.
Texture: clay loam, sandy clay loam, loam, or sometimes clay.
Clay content: 18 to 42 percent .
Rock fragments: 0 to 15 percent.
Artifacts: 0 to 10 percent construction debris (concrete, bricks, asphalt, glass).

2Bt(k ) horizon (when present)
Moist color: hue of 10YR or 7.5YR, value of 3 to 6, chroma of 4 to 6.
Texture: loam, clay loam, sandy clay loam or sandy loam.
Calcium carbonate: some pedons have masses of calcium carbonate
Rock fragments: 0 to 5 percent, some pedons have up to 25 percent rock fragments in the substratum.

COMPETING SERIES: This is the Dapplegray soil.
Dapplegray soils: have up to 35 percent rock fragments that have been detached from in-situ bedrock by machinery and mixed into the profile of cut and filled hillslope terraces on hills.

GEOGRAPHIC SETTING:
Landscape: alluvial plain, coastal plain.
Landform: locally raised land, hillslope terraces, cut and fill on existing alluvial fan remnants.
Parent material: human-transported materials originating from alluvium from primarily sedimentary sources.
Elevation: 0 to 300 meters.
Slope: 0 to 15 percent.
Climate: warm dry summers and cool moist winter.
Mean annual precipitation: 356 mm.
Mean annual air temperature: 17 to 18 degrees C.
Frost free season: 300 to 365 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Botella, Centinela, Counterfeit, Grommet, Montebello, Pierview, Ramona and Windfetch soils.
Botella soils: have a mollic epipedon and have an argillic horizon formed on remnant alluvium fans.
Centinela soils: have a fine particle-size class on uplifted alluvium and alluvial bottoms.
Counterfeit soils: have fine particle-size class on hillslope terraces.
Grommet soils: have a mollic epipedon and are formed from alluvium on slightly lower positions.
Montebello soils: have human-transported materials derived from material weathered from granitic sources, typically does not have calcium carbonate.
Pierview soils: have an argillic horizon that extends below a depth of 150 cm on nearby landscapes.
Ramona soils: have an argillic horizon and formed on remnant alluvial fans from granitic sources.
Windfetch soils: have a mollic epipedon and argillic horizon on nearby landscapes.

DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY: Well drained; low runoff; moderate saturated hydraulic conductivity.

USE AND VEGETATION: Sepulveda soils are used for residential neighborhoods in urban areas. Vegetation is ornamental plants, trees, and sod.

DISTRIBUTION AND EXTENT: Coastal plains and valleys of southern California; MLRA 19. These soils are of small extent.

SOIL SURVEY REGIONAL OFFICE (SSRO) RESPONSIBLE: Davis, California.

SERIES ESTABLISHED: Los Angeles County, California, 2016.

REMARKS:

Diagnostic features recognized in this pedon are:
Ochric Epipedon: the zone from a depth of 0 to 24 cm
Artifacts: the zone from a depth of 0 to 24 cm
Human transported materials: the zone from a depth of 0 to 200 cm
Particle size control section: the zone from a depth of 25 to 100 cm

Soil structure and secondary carbonates in the human-transported materials are considered geogenic properties having been formed prior to transport.

Taxonomic subgroup tagged as 'typic' due to presence of human-transported materials. The soil has properties and occurs on appropriate landforms to support the concept of human-transported materials. The use of the Anthroportic subgroup is not currently permitted in the xeric soil moisture regime, but will be explored for future consideration for correlation.

ADDITIONAL DATA:
User Site ID: S2015CA037001
Lab Pedon Number: 15N0539
Classified using the Twelfth Edition Keys to Soil Taxonomy (2014)

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National Cooperative Soil Survey
U.S.A.