LOCATION THOMSON SCEstablished Series
TAXONOMIC CLASS: Coarse-loamy, mixed, semiactive, thermic Ultic Hapludalfs
TYPICAL PEDON: Thomson sandy loam-cultivated. (Colors are for moist soil.)
Ap--0 to 9 inches; dark yellowish brown (10YR 4/4) sandy loam; weak fine granular; very friable; many fine roots; slightly acid; abrupt smooth boundary. (6 to 12 inches thick)
Bt1--9 to 30 inches; strong brown (7.5YR 4/6) sandy loam; weak fine subangular blocky structure; very friable; common fine roots; sand grains bridged and coated with clay; slightly acid; diffuse smooth boundary. (10 to 40 inches thick)
BC--30 to 59 inches; strong brown (7.5YR 5/6) sandy loam; weak fine subangular blocky structure; very friable; common fine roots; slightly acid; diffuse smooth boundary. (10 to 40 inches thick)
2Bt2--59 to 71 inches; yellowish red (5YR 5/8) sandy clay loam; few fine faint strong brown (7.5YR 5/8) mottles; weak fine subangular blocky structure; friable; common faint clay films on faces of peds; 2 percent fine manganese concretions; slightly acid; diffuse smooth boundary.
2Bt3--71 to 80 inches; strong brown (7.5YR 5/8) sandy clay loam; many medium prominent red (2.5YR 4/8) and many medium distinct brownish yellow (10YR 6/8) mottles; weak fine subangular blocky structure; friable; common faint clay films on faces of peds; slightly acid. (Combined thickness of the 2Bt horizons is 0 to 25 inches)
TYPE LOCATION: Chester County, South Carolina; about 16 miles northwest of Chester, South Carolina from the intersection of Secondary Road 307 (Cabal Road) and Secondary Road 742 (Thompson Quarters Road); about 1.1 miles west northwest on Secondary Road 742; about 2200 feet west southwest on farm road; 370 feet north; in field; Lockhart, South Carolina USGS topographic quadrangle; lat. 34 degrees 49 minutes 03 seconmds N and 81 degrees 28 minutes 09 seconds W.
RANGE IN CHARACTERISTICS:
Solum Thickness: 30 to 65 inches
Depth to Bedrock: Greater than 60 inches
Depth to Seasonal High Water Table: Greater than 60 inches
Soil Reaction: Moderately acid to slightly alkaline except where the surface has been limed
Gravel Content: Quartz gravel make up 0 to 5 percent of the solum and 0 to 15 percent of the C horizon in the non-flooded phase; 0 to 35 percent in the solum and 0 to 50 percent of the C horizon in the flooded phase
A or Ap horizon:
Color--hue of 7.5YR to 2.5Y, value of 3 to 6, and chroma of 1 to 4. Where the value is 3 and the chroma is 1 or 2, the A horizon is less than 6 inches thick.
Texture--loamy sand, loamy fine sand, sandy loam, fine sandy loam, or loam
E horizon (if it occurs)
Color--has hue of 10YR or 2.5Y, value of 4 to 7, and chroma of 4 or 6
Texture--loamy sand, loamy fine sand, sandy loam, fine sandy loam, or loam
BA or BE horizon (if it occurs)
Color--hue of 5YR to 2.5Y, value of 4 to 7, and chroma of 3 to 6
Texture--sandy loam, fine sandy loam, or loam
Bt horizon:
Color--hue of 5YR to 10YR, value of 4 to 6, and chroma of 4 to 8
Texture--sandy loam, fine sandy loam, or loam. Some pedons may have a thin subhorizon that is sandy. The lower boundary is gradual or diffuse or there is more than 50 percent fine and coarser sand in the B horizon.
BC or CB horizon (if it occurs)
Color--hue of 5YR to 10YR, value of 4 to 6, and chroma of 4 to 8
Texture--loamy sand or loamy fine sand
2Bt horizon:
Color--hue of 5YR to 10YR, value of 4 to 6, and chroma of 4 to 8
Texture--sandy loam, sandy clay loam, or loam.
C horizon (if it occurs):
Color--hue of 7.5YR to 2.5Y, value of 4 to 7, and chroma of 3 to 8
Texture--usually stratified and in the fine-earth portion, ranges from coarse sand to loamy fine sand
COMPETING SERIES:
Sekil soils-have a depth to hard bedrock of 20 to 40 inches and are on piedmont uplands
GEOGRAPHIC SETTING:
Landscape: Piedmont
Landform: Stream terraces and flood plains
Elevation: 100 to 250 feet above mean sea level
Parent Material: Loamy and sandy fluvial sediments
Mean Annual Air Temperature: 58 to 60 degrees
Mean Annual Precipitation: 40 to 50 inches
Frost Free Period: 190 to 220 days
GEOGRAPHICALLY ASSOCIATED SOILS:
Altavista soils--moderately well drained soils (seasonal high water table 18 to 30 inches) in fine-loamy family on slightly lower landscapes
Augusta soils--somewhat poorly drained soils (seasonal high water table 12 to 18 inches) in fine-loamy family on lower landscapes
Molena soils--somewhat excessively drained soils in sandy family on similar landscapes
Dogue soils--moderately well drained soils (seasonal high water table 18 to 30 inches) in fine family on slightly lower landscapes
Pamunkey soils--well drained soils (seasonal high water table 48 to 72 inches) in fine-loamy family with base saturation greater than 35 percent on similar landscapes
State soils--well drained soils (seasonal high water table 48 to 72 inches) in fine-loamy family on similar landscapes
Wickham soils--well drained soils (seasonal high water table is below 6 feet) in fine-loamy family on similar landscapes
DRAINAGE AND PERMEABILITY:
Agricultural Drainage Class: Well drained
Permeability: Moderately rapid
USE AND VEGETATION:
Major Uses: Mostly cultivated
Dominant Vegetation: Where cultivated--soybeans, pasture, and corn. Where wooded--loblolly pine, sweet gum, oak, hickory, and maple
DISTRIBUTION AND EXTENT:
Distribution: Piedmont of South Carolina, and possibly Georgia and North Carolina
Extent: Small
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Raleigh, North Carolina
SERIES PROPOSED: Chester County, South Carolina, 2005.
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REMARKS: Thomson soils were previously mapped as Molena Variant (SIR SC0092)
Diagnostic horizons and other features recognized in this pedon are:
a. Ochric epipedon -the zone between 0 and 9 inches (Ap horizon).
b. Argillic horizon -the zone between 9 and 30 inches (Bt horizon) and between 59 and 80 inches (2Bt2 and 2Bt3 horizons).
MLRA=136
REVISED=12/2030/05, DTA. This revision changed the taxonomic classification from coarse-loamy, mixed, thermic Typic Hapludult based on lab data. 10-06-DTA-This revision changes the location to a more typical site, within the same map unit, and extends the description to 80 inches.
ADDITIONAL DATA: Laboratory data from typical pedon and supporting pedons S04SC-023(1-3), Data may be obtained from Clemson University.
TABULAR SERIES DATA:
SOI-5 Soil Name Slope Airtemp FrFr/Seas Precip Elevation SC0092 THOMSON 0-10 58-60 190-220 40-50 100-250SOI-5 FloodL FloodH Watertable Kind Months Bedrock SC0092 NONE >60 >60
SOI-5 Depth Texture 3-Inch No-10 Clay% -CEC- SC0092 0-9 SL FSL L 0-0 95-100 3-8 SC0092 9-30 FSL L SL 0-0 95-100 11-16 SC0092 30-59 LFS SL L 0-0 75-100 1-8 SC0092 59-80 SCL L 0-0 75-100 18-30
SOI-5 Depth -pH- O.M. Salin Permeab Shnk-Swll SC0092 0-9 4.5-6.5 .5-2. 0-0 2.0-6.0 LOW SC0092 9-30 4.5-6.5 0.-.5 0-0 2.0-6.0 LOW SC0092 30-59 4.5-6.5 0.-.5 0-0 6.0-20 LOW SC0092 59-80 4.5-6.5 0.-.5 0-0 0.6-2.0 LOW