LOCATION POLKTON NC+VA
Established Series
Rev. DGS-DTA-AG:DTA
09/2025
POLKTON SERIES
MLRA(s): 136 (thermic part)
Soil Survey Regional Office (SSRO) Responsible: Southeast
Depth Class: Moderately deep
Agricultural Drainage Class: Moderately well drained
Index Surface Runoff: High
Saturated Hydraulic Conductivity Class: Low
Shrink-Swell Potential: Very high
Landscape: Piedmont uplands
Landform: Interstream divides, ridges, and side slopes
Parent Material: Residuum weathered from Triassic sandstone, mudstone, siltstone, or shale
Slope: 2 to 25
Mean Annual Air Temperature: 16 degrees C (61 degrees F)
Mean Annual Precipitation: 1118 millimeters (44 inches)
TAXONOMIC CLASS: Fine, mixed, active, thermic Oxyaquic Vertic Hapludalfs
TYPICAL PEDON: Polkton sandy clay loam--cultivated. (Colors are for moist soil unless otherwise stated.)
Ap--0 to 18 centimeters (0 to 7 inches); reddish brown (5YR 4/3) sandy clay loam; weak medium subangular blocky structure; friable, plastic, sticky; many fine roots; slightly acid; abrupt smooth boundary. (5 to 25 centimeters (2 to 10 inches) thick)
Btss1--18 to 46 centimeters (7 to 18 inches); red (2.5YR 4/6) clay; weak coarse prismatic structure parting to moderate medium angular blocky structure; extremely firm, very plastic, very sticky; common fine roots; common nonintersecting slickensides; common distinct clay films on faces of peds; many fine prominent brown (7.5YR 5/4) iron depletions; very strongly acid; clear wavy boundary.
Btss2--46 to 61 centimeters (18 to 24 inches); red (2.5YR 4/6) clay; weak coarse prismatic structure parting to moderate medium angular blocky structure; extremely firm, very plastic, very sticky; few fine roots; common nonintersecting slickensides; common distinct clay films on faces of peds; many fine prominent brown (7.5YR 5/4) and common fine prominent light gray (5YR 7/1) iron depletions; very strongly acid; clear wavy boundary. (Combined thickness of the Btss horizon is 30 to 63 centimeters (12 to 25 inches)
BC--61 to 91 centimeters (24 to 36 inches); dark reddish brown (2.5YR 3/4) clay loam; moderate medium subangular blocky structure; firm, plastic, sticky; few fine roots; 10 percent by volume rounded and angular weathered siltstone fragments; very strongly acid; clear wavy boundary. (0 to 25 centimeters (0 to 10 inches thick)
Cr--91 to 132 centimeters (36 to 52 inches); dark reddish brown (2.5YR 3/4) weathered, moderately fractured fine-grained siltstone Triassic siltstone.
R--132 centimeters (52 inches); hard, unweathered Triassic siltstone
TYPE LOCATION: Anson County, North Carolina; 3.3 miles south of Polkton on Secondary Road 1250 (Poplar Hill Church Road), 100 feet north of road in field.
Latitude--34.891944
Longitude-- -80.184167
Datum--WGS84
RANGE IN CHARACTERISTICS:
Solum thickness: 51 to 102 centimeters (20 to 40 inches)
Depth to soft bedrock: 51 to 102 centimeters (20 to 40 inches)
Depth to hard bedrock: 102 to 152 centimeters (40 to 60 inches) or more
Depth to Seasonal High Water Table: 46 to 76 centimeters (18 to 30 inches)
Rock Fragment Content: 0 to 10 percent, by volume, throughout
Soil Reaction: Very strongly acid to slightly acid in the Ap, A, and E horizons, unless limed and very strongly acid or strongly acid in the Btss, BC, and C horizons.
Thickness of the clayey Bt horizons having COLE of 0.09 or more: 51 to 102 centimeters (20 to 40 inches)
Extractable aluminum: high (10 to 25 me/100g) in the Btss horizon
RANGE OF INDIVIDUAL HORIZONS:
A or Ap horizon:
Color: hue of 5YR to 10YR, value of 4 to 6, chroma of 2 to 4
Texture: sandy loam, fine sandy loam, silt loam, or loam. Where eroded, it is sandy clay loam, clay loam, silty clay loam, or clay.
E horizon, (if it occurs):
Color: hue of 5YR to 10YR, value of 4 to 6, chroma of 3 to 6
Texture: sandy loam, fine sandy loam, loam, or silt loam
Btss horizon:
Color: hue of 2.5YR to 10YR, value of 3 to 6, chroma of 3 to 8
Texture: clay, silty clay, or sandy clay
Redoximorphic features: iron depletions in shades of yellow, brown, and gray. Iron depletions with chroma of 2 or less are below the upper 10 inches of the horizon and within a depth of 40 inches. Iron masses in shades of red, yellow, or brown
BC horizon:
Color: hue of 2.5YR to 10YR, value of 3 to 6, chroma of 3 to 8
Texture: silty clay loam, clay loam, or sandy clay loam
Redoximorphic features: iron depletions in shades of brown, yellow, or gray and masses of iron accumulation in shades of red, brown, or yellow
The C horizon (if it occurs):
Color: hue of 2.5YR to 2.5Y, value of 3 to 7, and chroma of 1 to 8 or mottled in shades of red, brown, yellow, or gray
Texture: variable and ranges from sandy loam to clay saprolite.
Cr horizon:
Texture: soft weathered Triassic siltstone, mudstone, shale, sandstone, or conglomerate
R horizon:
Texture: hard unweathered Triassic siltstone, mudstone, shale, sandstone, or conglomerate
COMPETING SERIES:
Iredell soils--formed in material weathered from diabase, diorite, gabbro, and other rocks high in ferro-magnesium minerals
White Store soils--have a depth to soft bedrock of 102 to 152 centimeters (40 to 60 inches)
GEOGRAPHIC SETTING:
Landscape: Piedmont uplands
Landform: Ridges and hill slopes
Landform: Interstream divides, ridges, and side slopes
Parent Material: Residuum weathered from Triassic sandstone, mudstone, siltstone, or shale
Avereage Annual Air Temperature: 14 to 18 degrees C (58 to 65 degrees F)
Average Annual Precipitation: 1092 to 1219 millimeters (43 to 48 inches)
Frost Free Period: 180 to 260 days
GEOGRAPHICALLY ASSOCIATED SOILS:
Brickhaven soils--lack vertic properties and have greater than 30% silt in the subsoil.
Carbonton soils--lack vertic properties and have greater than 30% silt in the subsoil.
Creedmoor soils--lack vertic properties
Green Level soils--are somewhat poorly drained and are very deep to bedrock
Mayodan soils--are well drained and lack vertic properties
Peakin soils--are well drained, lack vertic properties and have a depth to water table of 3 to 6 feet
Pinoka series soils are well drained, and have a loamy subsoil
DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY:
Agricultural Drainage Class: Moderately well drained
Index Surface Runoff: High
Saturated Hydraulic Conductivity: Low
USE AND VEGETATION:
Major Uses: Woodland
Dominant vegetation: Where wooded--loblolly pine, sweetgum, southern red oak, willow oak, and white oak. Understory plants include eastern red cedar, flowering dogwood, winged elm, eastern hophornbeam, eastern redbud, greenbrier, sassafras, honeysuckle, and poison ivy. Where cultivated--small grains, corn, cotton, hay, and tobacco.
SOIL SURVEY REGIONAL OFFICE (SSRO) RESPONSIBLE: Auburn, Alabama
DISTRIBUTION AND EXTENT:
Distribution: North Carolina, Virginia, and possibly South Carolina
Extent: Small
SERIES ESTABLISHED: Anson County, North Carolina; 1999.
REMARKS: Polkton soils were formerly included with the White Store series. However, White Store soils have a depth to soft bedrock of 102 to 152 centimeters (40 to 60 inches) The 9/2025 update changed the format. No data was changed.
Diagnostic features and horizons recognized in this pedon are:
Ochric epipedon--the zone from 0 to 18 centimeters (0 to 7 inches) (Ap horizon)
Argillic horizon--the zone from 18 to 61 centimeters (7 to 24 inches) Btss1 and Btss2 horizons)
Slickensides - presence of slickensides in the zone from 18 to 61 centimeters (7 to 24 inches) (Btss1 and Btss2 horizons)
Paralithic contact - the occurrence of weathered bedrock at a depth of 91 centimeters (36 inches) (upper boundary of the Cr horizon).
Lithic contact - the occurrence of hard bedrock at a depth of 132 centimeters (52 inches) (upper boundary of the R horizon)
Vertic feature: cracks within 127 centimeters (50 inches) that are 5 mm or more wide through a thickness of 30 centimeters (12 inches) or more for some time in normal years, and slickensides or wedge-shaped aggregates in a layer 15 centimeters (6 inches) or more thick that has its upper boundary within 127 centimeters (50 inches) of the soil surface; or a linear extensibility of 2.5 inches or more between the surface and either a depth of 102 centimeters (40 inches) or a paralithic contact, whichever is shallower
Oxyaquic feature: Saturation with water in one or more layers within 102 centimeters (40 inches) of the surface in normal years for either or both 20 or more consecutive days or 30 or more cumulative days.
ADDITIONAL DATA:
None
SIR: NC0285, NC0287 (Eroded)
TABULAR SERIES DATA:
SOI-5 Soil Name Slope Airtemp FrFr/Seas Precip Elevation
NC0285 POLKTON 2-25 58- 65 152-218 43-48 180-850
NC0287 POLKTON 2-25 58- 65 152-218 43-48 180-850
SOI-5 FloodL FloodH Watertable Kind Months Bedrock Hardness
NC0285 NONE 1.5-2.5 PERCHED DEC-MAR 20-40 SOFT
NC0287 NONE 1.5-2.5 PERCHED DEC-MAR 20-40 SOFT
SOI-5 Depth Texture 3-Inch No-10 Clay% -CEC-
NC0285 0-7 FSL SL 0-3 95-100 10-20 5-15
NC0285 0-7 L SIL 0-3 95-100 7-27 5-15
NC0285 7-24 C SC SIC 0-3 90-100 35-70 20-40
NC0285 24-36 CL SCL SICL 0-3 95-100 20-40 10-25
NC0285 36-52 WB - - - -
NC0285 52-62 UWB - - - -
NC0287 0-7 C 0-3 95-100 40-45 10-25
NC0287 0-7 SCL CL SICL 0-3 95-100 27-40 5-15
NC0287 7-24 C SC SIC 0-3 90-100 35-70 20-40
NC0287 24-36 CL SCL SICL 0-3 95-100 20-40 10-25
NC0287 36-52 WB - - - -
NC0287 52-62 UWB - - - -
SOI-5 Depth -pH- O.M. Salin Permeab Shnk-Swll
NC0285 0-7 4.5-6.5 .5-2. 0-0 0.6-2.0 LOW
NC0285 0-7 4.5-6.5 .5-2. 0-0 0.6-2.0 LOW
NC0285 7-24 4.5-5.5 0.-.5 0-0 0.0-0.06 VERY HIGH
NC0285 24-36 4.5-5.5 0.-.5 0-0 0.06-0.6 HIGH
NC0285 36-52 - - - 0.0-0.06
NC0285 52-62 - - - 0.0-0.01
NC0287 0-7 4.5-6.5 .1-.5 0-0 0.06-0.2 HIGH
NC0287 0-7 4.5-6.5 .2-1. 0-0 0.2-0.6 MODERATE
NC0287 7-24 4.5-5.5 0.-.5 0-0 0.0-0.06 VERY HIGH
NC0287 24-36 4.5-5.5 0.-.5 0-0 0.06-0.6 HIGH
NC0287 36-52 - - - 0.00-0.06
NC0287 52-62 - - - 0.00-0.01
________________________________________
National Cooperative Soil Survey
U.S.A.