IDENTIFIERS

  • Current Taxon Name (Soil Name): POSITAS
  • OSD
  • Series Extent
  • User Site ID: S1959CA001001
  • User Pedon ID: S1959CA001001
  • Lab Information:
  • Certified Lab Pedon Description - no
  • Lab Source ID - SSL
  • Lab Pedon # - 40A2928
  • NCSS Pedon Lab Data NASIS Record ID - 38057
  • Print Date: 1/30/2025

    • 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: 37.6502762
  • Std. Longitude: -121.6961136
  • Datum: WGS84
  • Township: 3S
  • Range: 2E
  • Section: 25
  • PLSS Details: 216 feet east of Greenville Road and 168 feet south of the northeast corner
  • Location Description: about 3 miles southeast of Livermore.
  • State: California
  • County: CA001—Alameda
  • MLRA: 15—Central California Coast Range
  • Non-MLRA Soil Survey Area: CA609—Alameda Area, California

    • PEDON

  • Describers Name: L. E. Welch
  • Current Taxonomic Class: Fine, smectitic, thermic Mollic Palexeralfs
  • Current Taxon Kind: series
  • Pedon Type: OSD pedon
  • Pedon Purpose: full pedon description
  • Pedon Record Orgin: Converted from PDP 3.x
  • Pedon #: 1
  • Correlated Information:
  • Soil Name - POSITAS
  • PSC - 25 to 100 cm.
  • Classificaton Date - 7/16/2007
  • Moisture Class - xeric
  • Sampled As Information:
  • Soil Name - Positas
  • Classificaton Date - 6/1/1959
  • Dynamic Soil Properties:
  • Pedoderm Loose Cover Indicator - no
  • Hydric: no


    • SITE

  • Landform: terrace
  • Runoff: medium
  • Drainage Class: well
  • Surface Fragments:
  • Benchmark Soil?: no

    • VEGETATION

    SITE OBSERVATION

  • Observation Date: 6/1/1959 (actual site observation date)
  • Surface Cover Properties:
  • Site Obs. Cover Kind 1 - crop cover
  • Pedoderm Loose Cover Indicator - no
  • Drained? - no
  • Bedded Soil? - no
  • Forest Plantation? - no
    • 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

    4

    —

    —

    183

    —

    225

    381

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    AP—0 to 20 centimeters (0.0 to 7.9 inches); brown (10YR 5/3), dark brown (7.5YR 3/2), moist; gravelly loam; massive; hard when dry, friable; 21.0 fine roots; 21.0 fine pores; fragments; moderately acid, pH 6.0, bromthymol blue; abrupt smooth boundary. Lab sample # 40A23095
    A3—20 to 28 centimeters (7.9 to 11.0 inches); brown (10YR 5/3), dark brown (7.5YR 3/2), moist; gravelly loam; massive; hard when dry, friable; 21.0 fine roots; 21.0 fine pores; fragments; moderately acid, pH 6.0, bromthymol blue; abrupt smooth boundary. Lab sample # 40A23096
    B21—28 to 51 centimeters (11.0 to 20.1 inches); dark reddish gray (5YR 4/2), dark reddish brown (5YR 3/3), moist; clay; strong coarse prismatic structure; extremely hard, extremely firm, moderately sticky, very plastic; 1.0 fine roots; 1.0 fine tubular pores; clay films on faces of peds and 30 percent slickensides (pedogenic); fragments; slightly acid, pH 6.5, unspecified; gradual smooth boundary. Lab sample # 40A23097. continuous - phpvsfiid 186654; continuous - phpvsfiid 186654
    B22—51 to 74 centimeters (20.1 to 29.1 inches); reddish brown (5YR 4/4), reddish brown (5YR 4/4), moist; clay; strong coarse prismatic structure; extremely hard, extremely firm, moderately sticky, very plastic; 1.0 fine roots; 1.0 fine tubular pores; clay films on faces of peds and 30 percent slickensides (pedogenic); fragments; moderately alkaline, pH 8.0, thymol-blue; abrupt smooth boundary. Lab sample # 40A23098. continuous - phpvsfiid 186656; continuous - phpvsfiid 186656
    B31—74 to 99 centimeters (29.1 to 39.0 inches); brown (7.5YR 5/4) and yellowish red (5YR 5/6), brown (7.5YR 4/4) and yellowish red (5YR 4/6), moist; clay loam; strong medium angular blocky structure; very hard, firm, moderately sticky, moderately plastic; 1.0 fine roots; 1.0 fine tubular pores; 30 percent clay films on faces of peds and in pores; 3 percent fine black (10YR 2/1) barite crystals; fragments; moderately alkaline, pH 8.0, thymol-blue; gradual smooth boundary. Lab sample # 40A23099. continuous - phpvsfiid 186658; continuous - phpvsfiid 186658
    B32—99 to 137 centimeters (39.0 to 53.9 inches); light yellowish brown (10YR 6/4), yellowish red (5YR 4/6), moist; clay loam; strong medium angular blocky structure; very hard, firm, moderately sticky, slightly plastic; 1.0 fine roots; 1.0 fine tubular pores; 30 percent clay films on faces of peds and in pores; 3 percent fine black (10YR 2/1) barite crystals; fragments; moderately alkaline, pH 8.0, thymol-blue; gradual smooth boundary. Lab sample # 40A23100. continuous - phpvsfiid 186659; continuous - phpvsfiid 186659
    C1—137 to 163 centimeters (53.9 to 64.2 inches); light yellowish brown (10YR 6/4), yellowish red (5YR 4/6), moist; gravelly sandy loam; massive; slightly hard, friable; fragments; moderately alkaline, pH 8.0, thymol-blue. Lab sample # 40A23101. 1 percent by volume of rocks over 3 feet in diameter and about 15 percent 1 to 3 inches in diameter