LOCATION HELENA NC+AL GA SC VA
Established Series
Rev. AG, MDJ, DTA
12/2025
HELENA SERIES
MLRA(s): 136 (thermic part)
Soil Survey Regional Office (SSRO) Responsible: Southeast
Depth Class: Very deep
Agricultural Drainage Class: Moderately well drained
Index Surface Runoff: Medium
Saturated Hydraulic Conductivity Class: Moderately low
Shrink-Swell Potential: High
Landscape: Piedmont uplands
Landform: Interstream divides, ridges, heads of drains, and side slopes
Parent Material: Residuum weathered from a mixture of felsic, intermediate, or mafic igneous or high-grade metamorphic rocks
Slope: 0 to 15 percent
Mean Annual Air Temperature: 15 degrees C (59 degrees F)
Mean Annual Precipitation: 1219 millimeters (48 inches)
TAXONOMIC CLASS: Fine, mixed, semiactive, thermic Aquic Hapludults
TYPICAL PEDON: Helena sandy loam - on a 4 percent slope in a cultivated field. (Colors are for moist soil unless otherwise stated.)
Ap--0 to 20 centimeters (0 to 8 inches); grayish brown (10YR 5/2) sandy loam; weak, medium, and coarse granular structure; very friable; many fine roots; moderately acid; abrupt smooth boundary. (10 to 25 centimeters (4 to 10 inches) thick)
E--20 to 30 centimeters (8 to 12 inches); light yellowish brown (10YR 6/4) sandy loam; weak medium granular structure; very friable; few fine roots; few fine black concretions; strongly acid; clear wavy boundary. (0 to 25 centimeters (0 to 10 inches) thick)
BE--30 to 48 centimeters (12 to 19 inches); brownish yellow (10YR 6/6) sandy clay loam; moderate medium prismatic structure that parts to moderate medium angular blocky; friable; sticky, plastic; few fine roots; few fine pores; few faint clay films on faces of peds; few medium quartz gravel; common fine faint pale brown (10YR 6/3) iron depletions; very strongly acid; clear wavy boundary. (0 to 18 centimeters (0 to 7 inches) thick)
Bt1--48 to 61 centimeters (19 to 24 inches); yellowish brown (10YR 5/8) clay; weak coarse angular blocky structure; firm; sticky, plastic; few fine roots; few fine pores; few faint clay films on faces of peds; few fine prominent light brownish gray (10YR 6/2) iron depletions; very strongly acid; clear wavy boundary.
Bt2--61 to 99 centimeters (24 to 39 inches); yellowish brown (10YR 5/8) clay; weak coarse subangular blocky and angular blocky structure; very firm, sticky, very plastic; few fine roots; few fine pores; common distinct clay films on faces of peds; many medium prominent gray (10YR 6/1) iron depletions; very strongly acid; clear wavy boundary.
Bt3--99 to 109 centimeters (39 to 43 inches); light yellowish brown (10YR 6/4) clay loam; weak medium subangular blocky structure; extremely firm, sticky, very plastic; common distinct clay films on faces of peds; few brown concretions; common medium distinct light gray (10YR 7/1) iron depletions; very strongly acid; clear wavy boundary. (Combined thickness of the Bt horizons is 43 to 107 centimeters (17 to 42 inches.)
BCg--109 to 117 centimeters (43 to 46 inches); light gray (10YR 7/1) clay loam; weak coarse subangular blocky structure; friable, sticky, plastic; many coarse prominent strong brown (7.5YR 5/6) soft masses of iron accumulation; very strongly acid; clear wavy boundary. (0 to 36 centimeters (0 to 14 inches) thick)
C--117 to 152 centimeters (46 to 60 inches); strong brown (7.5YR 5/8) sandy loam saprolite; many coarse prominent light gray (10YR 7/1) streaks; massive; friable; few coarse veins of gray clay; common fragments of granitic rock; very strongly acid.
TYPE LOCATION: Durham County, North Carolina; 0.4 mile west of Mangum Store on Secondary Road 1603; 400 feet north on a farm road; 400 feet east in a cultivated field. USGS Durham North, North Carolina topographic quadrangle.
Latitude--36.1946
Longitude-- -78.8291
Datum--WGS84
RANGE IN CHARACTERISTICS:
Depth to top of argillic horizon: 10 to 46 centimeters (4 to 18 inches)
Solum thickness: 102 to more than 152 centimeters (40 to more than 60 inches)
Depth to bedrock: Greater than 152 centimeters (60 inches)
Depth to Seasonal High Water Table: 46 to 76 centimeters (18 to 30 inches), January to April
Soil reaction: Extremely acid to moderately acid, except where limed.
Rock fragment content: 0 to 35 percent, by volume, throughout the profile; mostly gravel
Other features: Some pedons may have few to common dark concretions in the upper part of the profile
RANGE OF INDIVIDUAL HORIZONS:
A or Ap horizon:
Color--hue of 10YR or 2.5Y, value of 3 to 6, chroma of 1 to 4
Texture (fine-earth fraction)--loamy sand, loamy coarse sand, coarse sandy loam, fine sandy loam, sandy loam, or loam. Eroded phases are clay loam or sandy clay loam
E horizon:
Color--hue of 10YR to 5Y, value of 5 to 8, chroma of 2 to 4
Texture (fine-earth fraction)--loamy sand, loamy coarse sand, coarse sandy loam, fine sandy loam, sandy loam, or loam
BE or BA horizon:
Color--hue of 7.5YR to 5Y, value of 5 to 8, chroma of 3 to 8
Texture (fine-earth fraction)--coarse sandy loam, sandy loam, sandy clay loam or clay loam
Bt horizon:
Color--hue of 7.5YR to 5Y, value of 5 to 8, chroma of 3 to 8. In some pedons, the lower Bt horizon has 5YR hues or is multicolored in shades of yellow, brown, gray, or red.
Texture (fine-earth fraction)--clay loam, sandy clay, or clay. Some pedons have thin subhorizons of sandy clay loam.
Redoximorphic features--iron depletions with chroma of 2 or less occur within 61 centimeters (24 inches) of the upper boundary of the Bt horizon. Iron accumulations in shades of yellow, brown, or red may also be present.
Btg horizon, (if it occurs):
Color--hue of 10YR or 2.5Y, value of 4 to 7, chroma of 1 or 2.
Texture (fine-earth fraction)--clay loam, sandy clay, or clay. Some pedons have thin subhorizons of sandy clay loam.
Redoximorphic features--iron accumulations in shades of yellow, brown, or red are commonly present
BC horizon, (if it occurs):
Color--hue of 7.5YR to 5Y, value of 5 to 8, chroma of 3 to 8. Some pedons may have 5YR hues or are multicolored in shades of yellow, brown, gray, or red.
Texture (fine-earth fraction)--clay loam, sandy clay loam, loam, fine sandy loam, or sandy loam
Redoximorphic features--iron depletions in shades of brown, olive, or gray and iron accumulations in shades of yellow, brown, or red may also be present.
BCg horizon:
Color--hue of 10YR or 2.5Y, value of 4 to 7, chroma of 1 or 2
Texture (fine-earth fraction)--clay loam, sandy clay loam, loam, fine sandy loam, or sandy loam
Redoximorphic features--iron accumulations in shades of yellow, brown, or red are commonly present
C horizon:
Color--hue of 5YR to 5Y, value of 5 to 8, chroma of 3 to 8, or is multicolored in shades of gray, yellow, brown, red or white
Texture (fine-earth fraction)--sandy loam, fine sandy loam, sandy clay loam, or loam saprolite. Some pedons may have bodies or seams of clay loam or clay.
Redoximorphic features--iron depletions in shades of brown, olive, or gray and iron accumulations in shades of yellow, brown, or red.
Cg horizon, (if it occurs):
Color--hue of 10YR to 5Y, value of 5 to 7, chroma of 1 or 2 and is typically multicolored in shades of yellow or brown.
Texture (fine-earth fraction)--sandy loam, fine sandy loam, sandy clay loam, or loam saprolite. Some pedons may have bodies or seams of clay loam or clay.
Redoximorphic features--iron accumulations in shades of yellow, brown, or red
COMPETING SERIES:
Annemaine soils--have a redder hue and form from lower Coastal Plain sediments
Beason soils--have a higher silt content and have sediments from sedimentary rock origin
Buckatunna soils--form from Coastal Plain sediments
Bush River soils--have a paralithic contact at a depth of 40 to 60 inches
Chickasawhay soils--form in marine and Coastal Plain sediments
Cid soils--have a lithic contact at a depth of 20 and 40 inches
Craven soils--formed from Coastal Plain sediments and have a higher silt content
Creedmoor soils--have a very high shrink swell potential, more exchangeable aluminum and form from Triassic parent material
Dogue soils--have a higher silt content and form from Coastal Plain sediments
Dorian soils--have a moderate shrink-swell potential and form from fluvial sediments on stream terraces
Gritney soils--form from Coastal Plain sediments
Lignum soils--have a paralithic contact at a depth of 40 to 60 inches
Nemours soils--have a redder hue and form from Coastal Plain sediments
Newco soils--have a redder hue and form from Coastal Plain sediments
Prosperity soils--have a paralithic contact at a depth of 40 and 60 inches
Telfair soils--have a thinner solum and have a paralithic contact at a depth of 20 to 40 inches
GEOGRAPHIC SETTING:
Landscape: Piedmont
Landform: Ridges and hill slopes
Geomorphic Component: Interfluves and side slopes
Hillslope Profile Position: Toe slope, summits, and heads of drains
Parent Material: Residuum from aplitic granite or granite gneiss that is cut by dykes of gabbro and diorite, or mixed with hornblende schist or hornblende gneiss
Slope: 0 to 15 percent
Elevation: 107 to 274 meters (350 to 900 feet)
Frost-Free Period: 185 to 240 days
Mean Annual Air Temperature: 14 to 18 degrees C (58 to 65 degrees F)
Mean Annual Precipitation: 94 to 140 centimeters (37 to 55 inches)
GEOGRAPHICALLY ASSOCIATED SOILS:
Appling soils--are well drained and have a low shrink-swell potential
Cecil soils--are well drained, have a red subsoil, and have a low shrink-swell potential
Cullen soils--are well drained, have a red subsoil, and have a low shrink-swell potential
Durham soils--have less clay in the subsoil
Enon soils--are well-drained and have a higher base saturation
Hard Labor--soils have a moderate shrink-swell potential
Iredell soils--have a higher base saturation
Louisburg soils--are well drained and have less clay in the subsoil
Mecklenburg soils--are well drained, have a red subsoil, and have a higher base saturation
Pacolet soils--are well drained, have a red subsoil, and have a low shrink-swell potential
Rion soils--are well drained and have less clay in the subsoil
Santuc soils--have less clay in the subsoil
Sedgefield soils--have a higher base saturation
Vance soils--are well drained.
Wedowee soils--are well drained and have a low shrink-swell potential
Wilkes soils--are well drained, have a higher base saturation, and have a depth to paralithic contact of less than 20 inches
Worsham soils--are poorly drained
DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY:
Agricultural Drainage Class: Moderately well drained
Index Surface Runoff: Medium
Saturated Hydraulic Conductivity: Moderately low
USE AND VEGETATION:
Major Uses: Cropland, pasture and woodland
Dominant Vegetation: Where cultivated--tobacco, corn, soybean, small grain, and vegetables. Where wooded--a mix of hardwood and pine. Native species include loblolly pine, shortleaf pine, Virginia pine, sweetgum, willow oak, red oak, white oak, yellow-poplar, and American elm. Understory species include sourwood, flowering dogwood, winged elm, eastern cedar, hophornbean, eastern redbud, and sassafras.
SOIL SURVEY REGIONAL OFFICE (SSRO) RESPONSIBLE: Auburn, Alabama
DISTRIBUTION AND EXTENT:
Distribution: Alabama, Georgia, North Carolina, South Carolina, and Virginia.
Extent: Large.
SERIES ESTABLISHED: Person County, North Carolina, 1928.
REMARKS:
12/2012 Revision updates the format and added latitude and longitude.
8/1991 Revision changed depth to bedrock from "more than 48 inches to more than 60 inches" to be consistent with one depth to bedrock class as shown on the Soil Interpretation Records for Helena. The 12/2025 revision changed formatting. No data was changed.
Diagnostic horizons and features recognized in this pedon are:
Ochric epipedon--the zone from 0 to 30 centimeters (0 to 12 inches) (Ap and E horizons)
Argillic horizon--the zone from 30 to 117 centimeters (12 to 46 inches) (BE, Bt1, Bt2, Bt3 and BCg horizons)
Aquic conditions--periodic episaturation and reduction in a zone within the upper 61 centimeters (24 inches) of the argillic horizon
ADDITIONAL DATA:
TABULAR SERIES DATA:
SOI-5 Soil Name Slope Airtemp FrFr/Seas Precip Elevation
NC0058 HELENA 0-15 58-65 185-240 37-55 350-900
NC0176 HELENA 0-15 58-65 185-240 37-55 350-900
NC0266 HELENA 0-15 58-65 185-240 37-55 350-900
SOI-5 FloodL FloodH Watertable Kind Months Bedrock Hardness
NC0058 NONE 1.5-2.5 PERCHED JAN-APR >60
NC0176 NONE 1.5-2.5 PERCHED JAN-APR >60
NC0266 NONE 1.5-2.5 PERCHED JAN-APR >60
SOI-5 Depth Texture 3-Inch No-10 Clay% -CEC-
NC0058 0-12 SL FSL L 0-5 90-100 5-20 1-6
NC0058 0-12 SCL CL 0-5 95-100 20-35 4-8
NC0058 12-19 SCL CL 0-5 95-100 20-35 4-7
NC0058 19-43 CL SC C 0-5 95-100 35-60 7-13
NC0058 43-60 VAR - - - -
NC0176 0-12 GR-FSL GR-L GR-COSL 0-5 50- 75 5-20 1-6
NC0176 0-12 GR-LCOS GR-LS GR-S 0-5 50- 75 3-12 1-4
NC0176 0-12 GR-CL GR-SCL 0-5 50- 75 20-35 4-8
NC0176 12-19 SCL CL SL 0-5 95-100 20-35 4-7
NC0176 19-43 CL SC C 0-5 95-100 35-60 7-13
NC0176 43-60 VAR - - - -
NC0266 0-12 LS LCOS 0-5 90-100 3-12 1-4
NC0266 12-19 SCL CL 0-5 95-100 20-35 4-7
NC0266 19-43 CL SC C 0-5 95-100 35-60 7-13
NC0266 43-60 VAR - - - -
SOI-5 Depth -pH- O.M. Salin Permeab Shnk-Swll
NC0058 0-12 3.5-6.5 .5-2. 0-0 2.0-6.0 LOW
NC0058 0-12 3.5-6.5 .5-1. 0-0 0.2-0.6 LOW
NC0058 12-19 3.5-5.5 0.-.5 0-0 0.2-0.6 MODERATE
NC0058 19-43 3.5-5.5 0.-.5 0-0 0.06-0.2 HIGH
NC0058 43-60 - - - -
NC0176 0-12 4.5-6.5 .5-2. 0-0 2.0-6.0 LOW
NC0176 0-12 4.5-6.5 .5-2. 0-0 6.0- 20 LOW
NC0176 0-12 4.5-6.5 .5-1. 0-0 0.2-0.6 LOW
NC0176 12-19 4.5-5.5 0.-.5 0-0 0.2-0.6 MODERATE
NC0176 19-43 4.5-5.5 0.-.5 0-0 0.06-0.2 HIGH
NC0176 43-60 - - - -
NC0266 0-12 3.5-6.5 .5-2. 0-0 6.0- 20 LOW
NC0266 12-19 3.5-5.5 0.-.5 0-0 0.2-0.6 MODERATE
NC0266 19-43 3.5-5.5 0.-.5 0-0 0.06-0.2 HIGH
NC0266 43-60 - - - -
________________________________________
National Cooperative Soil Survey
U.S.A.