LOCATION FORK VA+GA NC
Established Series
Rev. DCH-JEW-RLV
10/2021
FORK SERIES
Soils of the Fork series are very deep and somewhat poorly drained. They formed in loamy alluvium or coastal plain sediments on low stream terraces. Slopes range from 0 to 7 percent. Mean annual precipitation is about 40 inches and mean annual temperature is about 57 degrees F.
TAXONOMIC CLASS: Fine-loamy, mixed, semiactive, thermic Aeric Endoaqualfs
TYPICAL PEDON: Fork fine sandy loam - under mixed hardwood forest. (Colors are for moist soil.)
0i--0 to 1 inches; undecomposed forest litter of leaves and twigs.
0e--1 to 2 inches; very dark grayish brown (10YR 3/2) decomposed organic matter.
A--2 to 3 inch; dark grayish brown (2.5Y 4/2) fine sandy loam; weak fine granular structure; very friable; many fine roots; very strongly acid; clear smooth boundary. (0 to 3 inches thick)
E--3 to 11 inches; grayish brown (2.5Y 5/2) fine sandy loam; few fine faint brown (10YR 5/3) mottles; weak fine granular structure; very friable; many fine and medium roots; very strongly acid; clear smooth boundary. (0 to 10 inches thick)
BE--11 to 20 inches; light olive brown (2.5Y 5/6) clay loam; many medium distinct light brownish gray (2.5Y 6/2) mottles; moderate fine subangular blocky structure; friable; many fine and medium roots; many fine and medium pores; very strongly acid; gradual smooth boundary. (6 to 12 inches thick)
Btg1--20 to 32 inches; grayish brown (2.5Y 5/2) clay loam; many medium distinct yellowish brown (10YR 5/4) mottles; moderate medium subangular blocky structure; slightly hard, friable, slightly plastic, sticky; common fine roots; few thin patchy clay films on faces of peds; strongly acid; gradual smooth boundary.
Btg2--32 to 40 inches; gray (N 6/0) clay loam; common medium prominent brownish yellow (10YR 6/6) mottles; moderate medium subangular blocky structure; hard, firm, sticky, plastic; thin continuous clay films on faces of peds; slightly acid; gradual smooth boundary. (combined thickness of Btg horizon is 12 to 30 inches)
BCg--40 to 54 inches; gray (5Y 6/1) silty clay loam; common medium distinct yellowish brown (10YR 5/6) mottles; weak medium subangular blocky structure; hard, friable, slightly sticky, slightly plastic; few thin clay films on faces of peds; few bodies of clay; neutral; gradual smooth boundary. (0 to 15 inches thick)
Cg--54 to 66 inches; gray (5Y 6/1) silty clay loam; common medium distinct light yellowish brown (10YR 6/4) and olive brown (2.5Y 4/4) mottles; massive; common fine rounded pebbles of quartz; few fine flakes of mica; neutral.
TYPE LOCATION: Louisa County, Virginia; on Highway 640, 220 yards west of Fork Creek.
RANGE IN CHARACTERISTICS: Solum thickness ranges from 40 to 60 inches or more. Depth to bedrock is more than 72 inches. 0 to 10 percent of rounded gravel of quartz are present in the A, E, BA, BE, Btg, and BCg horizons and 0 to 20 percent in the Cg horizon. Unless limed the soils are very strongly acid through moderately acid in the A and E horizons, very strongly acid through neutral in the BA, BE, Bt, Btg, and BCg horizons, and moderately acid or neutral in the Cg horizon.
The A horizon has hue of 10YR or 2.5Y, value of 2 or 4, and chroma of 1 to 4. It is fine sandy loam, loam, or silt loam.
The E horizon, where present, has hue of 10YR or 2.5Y, value of 4 or 5, and chroma of 2 to 4. Some pedons are mottled with higher chroma in the lower part. The E horizon is fine sandy loam, loam, or silt loam.
The BA or BE horizon has hue of 7.5YR to 2.5Y, value of 4 to 6, and chroma of 2 to 6. It is loamy fine sand, fine sandy loam, loam, or silt loam.
The Bt horizon, where present, has hue of 7.5YR to 2.5Y, value of 5 or 6, and chroma of 3 to 6. It is sandy clay loam, clay loam, or loam with less than 40 percent silt plus very fine sand.
The Btg horizon is neutral or has hue of 10YR to 5Y, value of 5 or 6, and chroma of 0 to 2. It is sandy clay loam, clay loam, or loam with less than 40 percent silt plus very fine sand.
The BCg horizon, where present, is neutral or has hue of 5YR to 5Y, value of 4 to 6, and chroma of 0 to 2. It is silty clay loam, sandy clay loam, sandy loam, fine sandy loam, loam, or loamy fine sand.
The Cg horizon has hue of 5YR to 5Y, value of 4 to 6, and chroma of 1 or 2. It is silty clay loam, sandy clay loam, sandy loam, loam, or loamy fine sand and commonly is stratified.
COMPETING SERIES: These are the
Bear Creek and
Plaza series in the same family. Bear Creek soils have a mean annual precipitation of less than 20 inches and are moderately deep over bedrock. Plaza soils have sola less than 40 inches thick and are calcareous in the lower part of the series control section.
GEOGRAPHIC SETTING: Fork soils are nearly level or gently sloping soils on low stream terraces or high flood plains in the Piedmont and Coastal Plain. Slopes range from 0 to 7 percent. These soils formed in alluvium or Coastal Plain sediments. The mean annual temperature is above 57 degrees F and the mean annual precipitation ranges from about 38 to 42 inches.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the
Altavista,
Forestdale, and
Pamunkey soils on stream terraces, and the
Congaree,
Chewacla, and
Wehadkee soils on stream flood plains. Altavista soils have less than 35 percent base saturation. Pamunkey soils do not have gray mottling or matrix colors within 20 inches of the top of the argillic horizon. Congaree, Chewacla, and Wehadkee soils do not have argillic horizons.
DRAINAGE AND PERMEABILITY: Somewhat poorly drained; slow to medium runoff; moderate permeability.
USE AND VEGETATION: More than half of these soils are in woodland and the remainder is in pasture and cultivation. Crops are small grain and mixed hay. Vegetation consists of post oak, willow oak, and scarlet oak; red maple, black gum, sweet gum, and Virginia pine.
DISTRIBUTION AND EXTENT: Virginia. The series is of small extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Raleigh, North Carolina
SERIES ESTABLISHED: Louisa County, Virginia, 1972.
REMARKS: The Fork soils had previously been included in mapping with the Augusta soils. The soil horizon depths were revised on 10/2021 to ensure the description began at the soil surface.
Diagnostic horizons and features recognized in this pedon are:
1. Ochric epipedon-the zone from 0 to 11 inches (O, A and E horizons)
2. Argillic Horizon-the zone from 20 to 40 inches (Btg horizons)
3. Base saturation greater than 60 percent.
MLRA = 133A, 136, 153A, 153B
ADDITIONAL DATA: Chemical analysis for samples from typical pedon in Louisa County, Virginia, (V.P.I. Soil Survey Laboratory Sample Nos. 534-540, 1971). Chemical analysis of samples of one pedon in Orange County, Virginia, (V.P.I. Soil Survey Laboratory, 1970).
TABULAR SERIES DATA:
SOI-5 Soil Name Slope Airtemp FrFr/Seas Precip Elevation
VA0078 FORK 0- 7 57- 62 185-225 38- 42 25- 250
SOI-5 FloodL FloodH Watertable Kind Months Bedrock Hardness
VA0078 NONE OCCAS 1.0-2.0 APPARENT DEC-MAR 60-60
SOI-5 Depth Texture 3-Inch No-10 Clay% -CEC-
VA0078 0- 11 FSL L SIL 0- 0 90-100 10-27 -
VA0078 0- 11 LS LFS 0- 0 90-100 2- 8 -
VA0078 11-54 CL SCL L 0- 0 90-100 18-35 -
VA0078 54-66 LFS SL SICL 0- 0 70-100 2-35 -
SOI-5 Depth -pH- O.M. Salin Permeab Shnk-Swll
VA0078 0- 11 4.5- 6.0 1.-3. 0- 0 2.0- 6.0 LOW
VA0078 0- 11 4.5- 6.0 1.-3. 0- 0 6.0- 20 LOW
VA0078 11-54 4.5- 7.3 .5-1. 0- 0 0.6- 2.0 LOW
VA0078 54-66 6.1- 7.3 .5-1. 0- 0 0.6- 20 LOW
National Cooperative Soil Survey
U.S.A.