LOCATION ASHBURN VAEstablished Series
TAXONOMIC CLASS: Fine-silty, mixed, active, mesic Oxyaquic Hapludalfs
TYPICAL PEDON: Ashburn silt loam-on a 2 percent slope in a corn field. (colors are for moist soil)
Ap--0 to 8 inches; yellowish brown (10YR 5/4) silt loam; moderate fine granular structure; friable, slightly sticky, nonplastic; strongly acid; abrupt smooth boundary (2 to 10 inches thick)
Bt1--8 to 26 inches; yellowish brown (10YR 5/6) silty clay loam; moderate fine subangular blocky structure; firm, slightly sticky, slightly plastic; many faint clay films on faces of peds; common medium distinct reddish brown (5YR 5/3) iron depletions on faces of peds; common medium distinct brownish yellow (10YR 6/8) soft masses of iron accumulation; strongly acid; gradual smooth boundary.
2Bt2--26 to 34 inches; yellowish red (5YR 4/6) silty clay loam; weak medium subangular blocky structure; firm, slightly sticky, slightly plastic; common distinct clay films on faces of peds; many faint reddish gray (5YR 5/2) and many medium light reddish brown (5YR 6/3) iron depletions on faces of peds; common medium distinct brownish yellow (10YR 6/8) soft masses of iron accumulation; strongly acid; gradual smooth boundary. (Combined thickness of the Bt horizon is 10 to 35 inches)
2C--34 to 39 inches; red (2.5YR 4/6) channery silty clay loam; massive; friable, slightly sticky, nonplastic; common medium faint reddish brown (5YR 5/4) soft masses of iron accumulation on surfaces of rock fragments; 30 percent siltstone channers; moderately acid; clear smooth boundary. (0 to 10 inches thick)
2R--39 inches; hard red siltstone bedrock.
TYPE LOCATION: Loudoun County, Virginia. 2000 feet east of the intersection of VA-647 and VA-641, and 2180 feet east northeast of the intersection of VA-642 and VA-641.
RANGE IN CHARACTERISTICS: Solum thickness ranges from 18 to 40 inches. Depth to soft or hard bedrock is 20 to 40 inches. Some Pedons with paralithic materials may not reach a lithic contact within 80 inches. Rock fragments of rounded vein quartz and red siltstone channers range from 0 to 5 percent in the Ap and Bt horizons. Rock fragments of red siltstone channers range from 0 to 35 percent in the 2Bt and 15 to 55 percent in the 2C horizons. Reaction is very strongly acid through moderately acid.
The A or Ap horizon has hue of 7.5YR or 10YR, value of 3 through 5, and chroma of 4 through 6. It is silt loam or loam.
The Bt horizon has hue of 7.5YR of 10YR, value of 4 through 6, and chroma of 3 through 6. It is silt loam or silty clay loam. Subhorizons may have textures of clay.
The 2Bt horizon has hue of 2.5YR or 5YR, value of 4 through 6, and chroma of 3 through 6. It is silt loam or silty clay loam in the fine-earth fraction. Subhorizons may have textures of clay.
The 2C horizon has hue of 10R through 5YR, value of 3 or 4, and chroma of 3 through 6. It is loam, silt loam, or silty clay loam in the fine-earth fraction.
The 2Cr horizon, where present, is dense in place and generally can be excavated with standard hand equipment. It is weathered red beds of variable grain size and bed thickness.
COMPETING SERIES: These are the Cidermill, Eilertsen, Elk, Elkinsville, Gallipolis, Parke, Pike, Rosine, Stonehead, Veronia, and Wellston series in the same family. All these soils are very deep to bedrock.
GEOGRAPHIC SETTING: Ashburn soils are on broad, convex interfluves in the Culpeper Basin of the northern Piedmont. These soils formed in reworked alluvium and the underlying red Triassic interbedded siltstone, fine-grained sandstone, and shale residuum. Slopes range from 0 to 8 percent. The mean annual air temperature ranges from 49 to 57 degrees F. Mean annual precipitation ranges from 35 to 45 inches.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Albano, Arcola, Dulles, and Panorama soils. Albano soils are poorly drained and are in drainageways. Arcola and Panorama soils are well drained and on similar landscape positions. Dulles soils are somewhat poorly drained and are in concave positions.
DRAINAGE AND PERMEABILITY: Moderately well drained. Runoff is medium. Permeability is moderate in the upper horizons and moderately slow in the lower horizons.
USE AND VEGETATION: Row crops, hay crops, residential uses. Some woodland of northern red oak and Virginia pine.
DISTRIBUTION AND EXTENT: Virginia and possibly Maryland and Pennsylvania. The series is of small extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Morgantown, West Virginia
SERIES ESTABLISHED: Loudoun County, Virginia, 2004.
Named for a village in Loudoun County.
REMARKS: Previously mapped as Readington soils. Diagnostic horizons and features recognized in this pedon:
1. Ochric epipedon-zone from the surface to 8 inches (Ap horizon)
2. Argillic horizon-zone from 8 to 34 inches (Bt1 and 2Bt2 horizons)
3. Lithologic discontinuity - at 26 inches (2Bt horizon)
4. Lithic contact - at 39 inches (2R horizon)
ADDITIONAL DATA: Mechanical analysis performed by Loudoun County, Virginia Department of Environmental Resources staff. Chemical analysis by Virginia Polytechnic Institute and State University. Lab numbers are: Loudoun County DER=74-B-1 through 74B-2-4; VPI&SU=8853372 through 8853375, and 8853361.