LOCATION GASTON             NC
Established Series
Rev. WEW:RAG
07/1999

GASTON SERIES


The Gaston series consists of very deep, well drained, moderately permeable soils on ridges and side slopes of the Piedmont uplands. They formed in residuum weathered from mixed intermediate and mafic crystalline rock such as hornblende, gneiss, quartz diorite, gabbro, and hornblende schist. Slope ranges from 2 to 25 percent. Mean annual temperature is 59 degrees F. and mean annual precipitation is 48 inches near the type location.

TAXONOMIC CLASS: Fine, mixed, active, thermic Humic Hapludults

TYPICAL PEDON: Gaston sandy clay loam--cultivated. (Colors are for moist soil unless otherwise stated).

Ap--0 to 6 inches; dark reddish brown (5YR 3/4), yellowish red (5YR 5/4) dry, sandy clay loam; weak medium granular structure; friable; many fine roots; slightly acid; clear smooth boundary. (3 to 10 inches thick)

Bt1--6 to 14 inches; dark red (2.5YR 3/6) clay; moderate medium subangular blocky structure; firm; sticky, plastic; common fine and few medium roots; common distinct clay films on faces of peds; few black streaks; moderately acid; gradual wavy boundary. (5 to 38 inches thick)

Bt2--14 to 47 inches; red (2.5YR 4/6) clay; few medium distinct reddish yellow (7.5YR 6/8) mottles; moderate medium subangular blocky structure; firm; sticky, plastic; common fine roots; common distinct clay films on faces of peds; few fine flakes of mica; few black streaks; moderately acid; clear wavy boundary. (10 to 45 inches thick)

BC--47 to 57 inches; red (2.5YR 4/6) clay loam; common medium prominent reddish yellow (7.5YR 6/8) mottles; weak medium subangular blocky structure; friable, slightly sticky, slightly plastic; common fine flakes of mica; few pockets of weathered black minerals; moderately acid; clear wavy boundary. (0 to 24 inches thick)

C--57 to 72 inches; red (2.5YR 4/6), yellowish red (5YR 5/6), and yellowish brown (10YR 5/4) saprolite that has a loam texture; rock controlled structure; common black specks and streaks; common fine flakes of mica; moderately acid.

TYPE LOCATION: Gaston County, North Carolina; 5 miles south of Belmont on NC Highway 273; 0.9 mile south on State Road 2525; 500 feet south on field road, 250 feet west of road.

RANGE IN CHARACTERISTICS: Solum thickness is 40 to more than 60 inches. Depth to bedrock is greater than 6 feet. The soil ranges from strongly acid through slightly acid. Most pedons have few to common flakes of mica in the B horizon and few to many flakes of mica in the BC and C horizons.

The A or Ap horizon has hue of 2.5YR to 7.5YR, value of less than 4, and chroma of 3 to 6. The A horizon, where present, is at least 6 inches thick. It is loam, fine sandy loam, sandy clay loam, clay loam, or gravelly analogues of these textures.

The Bt horizon has hue of 10R or 2.5YR, value of 3 or 4, and chroma of 4 to 8 when moist. Dry value less than 5 that is no more than 1 unit higher than the moist value is restricted to the upper subhorizons of the Bt horizon. High chroma mottles and dark streaks or stains occur in most pedons. It is clay or clay loam.

The BC horizon, if present, has hue of 2.5YR or 5YR, value of 4 to 6, and chroma of 4 to 8. High chroma mottles and dark streaks or stains occur in most pedons. It is clay loam, sandy clay loam, or loam.

The C horizon is commonly multicolored in shades of red, yellow, and brown. It is saprolite weathered from mixed acid and basic crystalline rock that has loamy textures.

COMPETING SERIES: The Farragut series is the only other known series in the same family. Farragut soils have textures of silty clay, silty clay loam, or clay in the Bt horizon and are formed from a thin layer of colluvium over shale residuum. Series in closely related families are the Cecil, Clifton, Coronaca, Cullen, Davidson, Georgeville, Gwinnett, Hanceville, Lloyd, Madison, Mecklenburg, Pacolet, Stoneville, and Tatum series. Cecil, Coronaca, Davidson, Georgeville, Gwinnett, Lloyd, Madison, and Pacolet soils are kaolinitic. In addition Cecil, Georgeville, Madison, and Pacolet soils do not have horizons with moist value less than 4. Madison soils have a high content of mica flakes. Pacolet soils have thinner clayey horizons. Coronaca soils are Alfisols. Coronaca, Davidson, Gwinnett, and Lloyd soils have rhodic colors throughout or in the upper part of the kandic horizon. Cullen soils do not have A horizons as thick as 6 inches that have moist value less than 3.5. Hanceville and Stoneville soils have rhodic colors throughout the argillic horizon and formed in residuum weathered from sedimentary rock. Clifton, Mecklenburg, and Tatum soils do not have A horizons thicker than 6 inches that have moist value less than 4. Clifton soils are mesic. Mecklenburg soils are less acid and have slow permeability. Tatum soils formed in sericite schist or phyllite.

GEOGRAPHIC SETTING: Gaston soils are on gently sloping to moderately steep uplands of the Piedmont plateau. Slope gradients are dominantly 2 to 15 percent but range from 2 to 25 percent. These soils formed in residuum weathered from mixed basic and acidic crystalline rocks such as quartz diorite, granite, gabbro, hornblende gneiss, mafic gneiss, and hornblende schist. Near the type location, average annual precipitation is about 48 inches. Mean annual temperature is about 59 degrees F.

GEOGRAPHICALLY ASSOCIATED SOILS: In addition to the competing Cecil, Cullen, Davidson, Gwinnett, Lloyd, Madison, Mecklenburg, and Pacolet series, are Enon, Helena, Iredell, Sedgefield, and Worsham series. Cecil, Cullen, Davidson, Gwinnett, Lloyd, Madison, Mecklenburg, and Pacolet soils occur in the same landscape positions as Gaston soils. Enon, Helena, Iredell, and Sedgefield soils are on toe slopes OR THE smoother parts of ridges. In addition, Enon, Helena, Iredell, and Sedgefield soils have yellower hue and Helena, Iredell, and Sedgefield soils have low chroma mottles in the B horizon. In addition, Iredell soils are smectitic. Worsham soils have dominant chroma of 2 or less and are in depressions and along intermittent drains.

DRAINAGE AND PERMEABILITY: Well drained, medium to rapid runoff, medium internal drainage, and moderate permeability.

USE AND VEGETATION: More than half of the acreage is in cultivation or pasture with the remainder in forest. Crops include small grains, corn, soybeans, and pasture plants. In forested areas shortleaf pine, loblolly pine, Virginia pine, hickory, northern red oak, southern red oak, scarlet oak, red maple, black oak, eastern white pine, yellow- poplar, white oak, and sweetgum are common trees. The understory includes flowering dogwood, grape, sourwood, common trumpet creeper, witch hazel, common persimmon, winged elm, eastern redbud, eastern red cedar, sassafras, eastern hophornbeam, and American holly.

DISTRIBUTION AND EXTENT: Piedmont areas of North Carolina and possibly Alabama, Georgia, South Carolina and Virginia. The series is of large extent.

MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Raleigh, North Carolina

SERIES ESTABLISHED: Gaston County, North Carolina; 1985.

REMARKS: This series was formerly included with Cullen series and originally fitted in the concept of the Lloyd series in North Carolina. The large acreage (25,000 acres in Gaston and Lincoln Cos., NC) of soil similar to Cullen but having dark surface layers with moist value less than 3.5 and dry value less than 6 in the Ap horizon supports proposal of this series.

Diagnostic horizons recognized in this pedon are:

Ochric epipedon - the zone from the surface of the soil to a depth of 6 inches (Ap horizon).

Argillic horizon - the zone from a depth of 6 inches to a depth of 47 inches (Bt1 and Bt2 horizons).

ADDITIONAL DATA: NC State University-
Apparent CEC B.S.
Pedon Horizon Depth (in.) Me/100g clay percent
1 Bt2 8 - 23 53.5
1 BC 53 - 60 6.2
2 Bt1 10 - 24 51.8
2 C 55 - 60 3.9
3 Bt 8 - 24 50
3 BC 55 - 60 2.7
4 Bt1 7 - 28 23.7
5 Bt1 12 - 24 34.8

TABULAR SERIES DATA:
SOI-5 Soil Name Slope Airtemp FrFr/Seas Precip Elevation
NC0170 GASTON 0- 25 58- 65 180-220 45- 55 400-1200

SOI-5  FloodL FloodH Watertable Kind   Months  Bedrock Hardness
NC0170 NONE          6.0-6.0              -     60-60        

SOI-5 Depth Texture 3-Inch No-10 Clay% -CEC- NC0170 0- 6 L FSL 0- 5 84-100 15-27 4- 15 NC0170 0- 6 CL SCL 0- 5 84-100 20-40 5- 20 NC0170 6-47 C CL 0- 5 90-100 35-70 5- 30 NC0170 47-57 CL SCL L 0- 5 84-100 20-40 4- 15 NC0170 57-72 VAR - - - -

SOI-5 Depth -pH- O.M. Salin Permeab Shnk-Swll NC0170 0- 6 5.1- 7.3 .5-3. 0- 0 2.0- 6.0 LOW NC0170 0- 6 5.1- 7.3 .5-3. 0- 0 0.6- 2.0 LOW NC0170 6-47 4.5- 6.5 0.-.5 0- 0 0.6- 2.0 MODERATE NC0170 47-57 4.5- 6.5 0.-.5 0- 0 0.6- 2.0 LOW NC0170 57-72 - - - -


National Cooperative Soil Survey
U.S.A.