IDENTIFIERS

  • Current Taxon Name (Soil Name): SWEENEY
  • OSD
  • Series Extent
  • User Site ID: S1955CA081009
  • User Pedon ID: S1955CA081009
  • Vegetation Plot ID: S1955CA081009
  • Lab Information:
  • Certified Lab Pedon Description - no
  • Lab Source ID - SSL
  • Lab Pedon # - 40A3061
  • NCSS Pedon Lab Data NASIS Record ID - 38190
  • Print Date: 2/17/2025

    • LOCATION

  • Location In Web Soil Survey
  • AOI is roughly a square mile and pedon is marked in the center.
  • Location in SoilWeb
  • Location in Google Maps
  • Std. Latitude: 37.3483315
  • Std. Longitude: -122.2344437
  • Datum: WGS84
  • Location Description: California in the San Mateo County SCD, west side of Highway 5 (Skyline Highway), 3.65 miles south of Sky Londa, 100 feet north of US Coast and Geodetic survey benchmark No. 0.387 dated 1936.
  • State: California
  • County: CA081—San Mateo
  • MLRA: 4B—Coastal Redwood Belt
  • Non-MLRA Soil Survey Area: CA637—San Mateo Area, California

    • PEDON

  • Describers Name: Ralph E. Nelson
  • Current Taxonomic Class: Fine-loamy, mixed, mesic Pachic Haploxerolls
  • Pedon Type: taxadjunct to the series
  • Pedon Purpose: full pedon description
  • Pedon Record Orgin: Converted from PDP 3.x
  • Pedon #: 9
  • Correlated Information:
  • Soil Name - SWEENEY
  • PSC - 25 to 100 cm.
  • Classificaton Date - 7/16/2007
  • Moisture Class - xeric
  • Sampled As Information:
  • Soil Name - Sweeney
  • Classificaton Date - 5/17/1955
  • Dynamic Soil Properties:
  • Pedoderm Loose Cover Indicator - no
  • Hydric: no


    • SITE

  • Landscape: hills
  • Landform: mountain
  • Slope Shape Down: concave
  • Drainage Class: moderately well
  • Surface Fragments:
  • Benchmark Soil?: no

    • VEGETATION

    SITE OBSERVATION

  • Observation Date: 5/17/1955 (actual site observation date)
  • Surface Cover Properties:
  • Pedoderm Loose Cover Indicator - no
  • Drained? - no
  • Bedded Soil? - no
  • Forest Plantation? - no
    • Vegetation Plot Plants
    Plant Symbol Scientific Name National Vernacular Name Plant Type Group Canopy Cover % Vegetation Stata Level

    AVFA

    MEPO3

    Avena fatua

    Medicago polymorpha

    wild oat

    burclover

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    Setting and Climate
    Slope Slope Length USLE Upslope Length Elev. Corr. Elev Aspect MAP REAP FFD MAAT MSAT MWAT MAST MSST MWST MFFP PE Index Climate Station ID Climate Station Name Climate Station Type
    % m degrees mm mm C mm

    6

    —

    —

    640

    —

    135

    940

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    A1—0 to 15 centimeters (0.0 to 5.9 inches); dark grayish brown (10YR 4/2), very dark brown (10YR 2/2), moist; silty clay loam; moderate fine and medium granular structure; hard when dry, friable, nonsticky, slightly plastic; 21.0 roots; 21 percent worm casts; fragments; neutral, pH 7.0, unspecified; clear smooth boundary. Lab sample # 40A23965. This horizon contains many roots and many worm casts.
    B2—15 to 43 centimeters (5.9 to 16.9 inches); dark grayish brown (10YR 4/2), very dark brown (10YR 2/2) and very dark grayish brown (10YR 3/2), moist; silty clay loam; weak medium subangular blocky structure; hard when dry, firm, nonsticky, slightly plastic; 21.0 roots; clay films on vertical faces of peds; 1 percent worm casts; fragments; neutral, pH 7.0, unspecified; clear wavy boundary. Lab sample # 40A23966. continuous - phpvsfiid 186701; continuous - phpvsfiid 186701
    B3—43 to 58 centimeters (16.9 to 22.8 inches); brown (10YR 4/3) and dark grayish brown (10YR 4/2), dark brown (10YR 3/3) and very dark grayish brown (10YR 3/2), moist; clay loam; weak fine and medium subangular blocky structure; hard when dry, firm, slightly sticky, moderately plastic; 21.0 roots; clay films on vertical faces of peds; 1 percent worm casts; fragments; neutral, pH 7.0, unspecified; clear boundary. Lab sample # 40A23967. patchy - phpvsfiid 186670; patchy - phpvsfiid 186670
    C1—58 to 76 centimeters (22.8 to 29.9 inches); yellowish brown (10YR 5/4) and dark brown (10YR 3/3), dark yellowish brown (10YR 4/4) and very dark grayish brown (10YR 3/2), moist; clay loam; weak medium subangular blocky structure; hard when dry, firm, slightly sticky, slightly plastic; 0.1 roots; clay films on vertical faces of peds; fragments; neutral, pH 7.0, unspecified; gradual wavy boundary. Lab sample # 40A23968. There are some thin patchy clay skins on vertical surfaces and dark metallic segregations which glisten in the sunlight.; patchy - phpvsfiid 186671; patchy - phpvsfiid 186671
    C2—76 to 122 centimeters (29.9 to 48.0 inches); yellowish brown (10YR 5/4) and dark brown (10YR 3/3), dark yellowish brown (10YR 4/4) and very dark grayish brown (10YR 3/2), moist; loam; massive, and weak medium subangular blocky; hard when dry, firm, very sticky, slightly plastic; fragments; neutral, pH 7.0, unspecified; gradual wavy boundary. Lab sample # 40A23969. There are darker colored metallic segregations which appear to be iron and manganese coatings on the weathered rock fragments.
    C3—122 to 163 centimeters (48.0 to 64.2 inches); yellowish brown (10YR 5/4) and strong brown (7.5YR 5/6) and pale yellow (2.5Y 8/2), dark yellowish brown (10YR 4/4) and strong brown (7.5YR 5/6) and strong brown (7.5YR 5/8), moist; loam; massive; hard when dry, friable, nonsticky, nonplastic; dark brown (10YR 3/3), moist, coats and very dark grayish brown (10YR 3/2), moist,; fragments; neutral, pH 7.0, unspecified; gradual wavy boundary. Lab sample # 40A23970. There are darker metallic segregations, probably iron and manganese.
    C4—163 to 178 centimeters (64.2 to 70.1 inches); yellowish brown (10YR 5/4) and strong brown (7.5YR 5/6) and pale yellow (2.5Y 8/2), dark yellowish brown (10YR 4/4) and strong brown (7.5YR 5/6) and strong brown (7.5YR 5/8), moist; sandy loam; massive; fragments. Lab sample # 40A23971. This material grades at variable depth into the hard diabase bedrock.