LOCATION PHILOMONT VAEstablished Series
TAXONOMIC CLASS: Coarse-loamy, mixed, semiactive, mesic Typic Hapludults
TYPICAL PEDON: Philomont loam - on a smooth ridgetop in a corn field. (Soil was moist when described.)
Ap-- 0 to 6 inches; dark yellowish brown (10YR 3/4) gravelly sandy loam; moderate fine granular structure; friable, non-sticky and non-plastic; 20 percent quartz gravel; many fine and medium roots; many very fine and fine pores; strongly acid; abrupt smooth boundary (5 to 11 inches thick).
Bt1-- 6 to 26 inches; brown (7.5YR 5/4) gravelly sandy loam; moderate medium and fine subangular blocky structure; friable, non-sticky and non-plastic; 30 percent quartz and gneiss gravel; few thin clay films on faces of peds; few fine and very fine roots; common very fine and fine pores; moderately acid; clear smooth boundary (5 to 20 inches thick).
Bt2-- 26 to 47 inches; yellowish red (5YR 5/6) sandy loam; weak medium and coarse subangular blocky structure; very friable, slightly sticky and non-plastic; 15 percent quartz gravel; common distinct clay films on faces of peds; many very fine and fine pores; strongly acid; gradual smooth boundary; (4 to 9 inches thick).
C-- 47 to 63 inches; yellowish red (5YR 5/6) weathered gneissic material; mottled in shades of strong brown, yellow, and red gravelly loam; massive; friable, slightly sticky and non-plastic; 20 percent quartz gravel; common fine mica flakes; strongly acid.
TYPE LOCATION: Loudoun County, Virginia. 0.48 miles west southwest of the junction of Virginia Route 745 and Virginia Route 626, and 250 feet east of Virginia Route 745. Virginia grid coordinates N. 489,800; E. 2,208,350.
RANGE IN CHARACTERISTICS: The thickness of the solum ranges from 20 to more than 50 inches. Depth to hard bedrock is greater than 60 inches. Coarse fragments of quartz and gneiss range from 0 to 35 percent in the Ap, Bt, BC, and C horizons. Soil reaction ranges from strongly acid or very strongly acid.
The Ap horizon has hue of 5YR through 10YR, value of 3 through 6, and chroma of 3 or 4. It is sandy loam or loam in the fine earth fraction.
The Bt horizon has hue of 5YR through 10YR, value of 4 through 6, and chroma of 4 through 6. It is sandy loam, loam, sandy clay loam, or clay loam in the fine earth fraction. The control section averages less than 18 percent clay.
The BC or BCt horizon, where present, is variegated gneissic material. It is sandy loam or loam in the fine earth fraction.
The C horizon is variegated weathered gneiss often intruded with thin lenses of basic greenstone. It is sandy loam or loam in the fine earth fraction and often has thin layers of clay loam or clay.
COMPETING SERIES: These are the Brentsville, Dunellen, Lansdale, Rigley, and Tankerville series. Brentsville and Tankerville soils are moderately deep over lithic or paralithic materials. Dunellen soils have stratified sand and gravel within 40 inches of the surface. Ridgely soils have a thicker solum.
GEOGRAPHIC SETTING: Philomont soils formed in gneissic and granitic rocks in the Blue Ridge uplands that have been intruded and sheared with basic greenstones. They occupy summits, shoulders, and upper back slopes. Slopes range from 0 to 15 percent. Mean annual air temperature is about 55 degrees F. Mean annual precipitation is about 42 inches.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Catoctin, Purcellville, Swampoodle, and Tankerville series. Tankerville and Catoctin soils are on similar landforms and are shallower to lithic or paralithic contact. Purcellville soils are on gently sloping ridgetops and contain more than 18 percent clay in the particle size control section. Swampoodle soils are in adjacent upland drainageways and are moderately well drained.
DRAINAGE AND PERMEABILITY: Philomont soils are well drained. Runoff is medium, Permeability is moderate to moderately rapid.
USE AND VEGETATION: The majority of the Philomont soils are cultivated and used for permanent pasture or row crops. A significant area has been developed for residential use. A small area is in woodland. Corn is the principle row crop. Fescue, orchard grass, and red clover are typical pasture mixes. Native vegetation is upland hardwood forest with some bluegrass in open areas.
DISTRIBUTION AND EXTENT: Virginia, Maryland, and possibly Pennsylvania and Delaware. The series is of small extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Morgantown, West Virginia
SERIES ESTABLISHED: Loudoun County, Virginia, 2004
REMARKS: Philomont is a community in western Loudoun County. These soils were previously mapped in the Brandywine series.
Diagnostic horizons recognized in this pedon are:
a) Ochric epipedon - The zone from 0 to 6 inches (Ap
horizon)
b) Argillic horizon - The zone from 6 to 47 inches (Bt1
and Bt2 horizons)
Mechanical, mineralogical, and chemical analyses for 21 pedons performed by Virginia Polytechnic Institute and State University staff.