LOCATION CLAPHAM VAEstablished Series
TAXONOMIC CLASS: Fine-silty, mixed, semiactive, mesic Typic Fragiudults
TYPICAL PEDON: Clapham silt loam - on a 2 percent slope in a hardwood forest. (Colors are for moist soil.)
A--0 to 9 inches; yellowish brown (10YR 5/4) silt loam; weak and medium subangular blocky structure; friable, non-sticky and slightly plastic; common very fine and fine roots; many fine and medium pores; very strongly acid; abrupt smooth boundary. (1 to 10 inches thick).
Bt1--9 to 20 inches; yellowish brown (10YR 5/6) silty clay loam; weak medium subangular blocky structure; friable, slightly sticky and slightly plastic; few fine and medium roots; very strongly acid; clear smooth boundary. (2 to 12 inches thick).
Btx--20 to 30 inches; yellowish brown (10YR 5/6) silty clay loam; weak coarse prismatic parting to weak medium platy structure; very firm, nonsticky and nonplastic; few fine roots; common distinct clay films on ped faces; few fine yellowish red (5YR 5/8) iron accumulations and few medium gray (10YR 5/1) iron depletions, thin continuous gray (10YR 6/1) clay flows along prism walls; very strongly acid; gradual smooth boundary. (9 to 23 inches thick).
B't1--30 to 54 inches; yellowish brown (10YR 5/6) silty clay loam; moderate, fine and medium subangular blocky structure; firm, sticky and plastic; common distinct clay films on ped faces; few fine distinct yellowish red (5YR 5/8) iron accumulations and gray (10YR 6/1) iron depletions; very strongly acid; gradual wavy boundary.
B't2--54 to 84 inches; mottled yellowish brown (10YR 5/6), light brownish gray (10YR 6/2), and red (2.5YR 4/8) clay; moderate, fine and medium subangular blocky structure; firm, sticky and plastic; many grayish brown (10YR 5/2) clay films on vertical ped faces; 2 percent rounded pebbles; strongly acid. (combined thickness of Bt is 14 to 54 inches).
C--84 to 102 inches; mottled strong brown (7.5YR 5/6), yellowish red (5YR 5/6), gray (10YR 6/1), and brown (7.5YR 5/4) clay; massive; very firm, sticky and plastic; many grayish brown(10YR 5/2) clay films on vertical ped faces; strongly acid.
TYPE LOCATION: Loudoun County, Virginia. North of McCarty Circle in the Cascades subdivision on planimetric map number 27, Virginia grid coordinates N 508,700 E 2,306,120.
RANGE IN CHARACTERISTICS: The thickness of the solum is more than 60 inches. Depth to hard bedrock is more than 60 inches. A seasonal perched water table is encountered at approximately 8 inches. The depth to a fragipan ranges from 8 to 30 inches. The fragipan normally is part of the argillic horizon, but in some pedons it overlies the argillic. Rock fragments of subrounded gravels comprise 0 to 5 percent of the soil profile. The particle size control section contains 7 to 14 percent fine sand or coarser material by weight.
The A or Ap horizon has hue of 10YR through 5YR, value of 3 through 5 and chroma of 3 through 6. It is silt loam or loam in the fine-earth fraction.
The Bt horizon, has hue of 10 YR through 5YR, value of 4 through 6 and chroma of 3 through 6. It is silt loam in the fine-earth fraction.
The Btx horizon has hue of 10YR of 7.5YR, value of 4 through 6, and chroma of 2 through 6. It is silt loam or silty clay loam in the fine-earth fraction. It normally has iron depletions on the ped faces.
The B't horizon has hue of 7.5YR through 10YR, value of 4 through 6 and chroma of 3 through 6. It is silt loam, silty clay loam, silty clay or clay in the fine-earth fraction. It normally has iron accumulations and iron depletions on ped faces and in pore linings.
COMPETING SERIES: These are the Bedford, Butlertown, Jennings, Medora and Tilsit series. Bedford and Medora soils have a loess mantle 12 to 24 inches thick. Butlertown soils have fragipans beginning deeper than 30 inches. Tilsit soils have sola less than 60 inches thick. Jennings soils have residuum beginning between 40 and 60 inches.
GEOGRAPHIC SETTING: Clapham soils are on natural levees of high river terraces. Slopes range from 0 to 7 percent and are convex or linear. The soils are forming in transported parent materials derived from old alluvium that washed from uplands underlain by limestone, granitic rocks and metamorphosed schist. Mean annual precipitation ranges from 35 to 45 inches, and mean annual air temperature ranges from 50 to 55 degrees F.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Elsinboro, Kinkora, Goresville and Hibler soils. Goresville and Elsinboro soils are well drained. Kinkora soils are poorly drained. Hibler soils do not have a fragipan.
DRAINAGE AND PERMEABILITY: Moderately well to somewhat poorly drained. Runoff is slow to medium. Permeability is slow.
USE AND VEGETATION: The majority of the Clapham soils are cultivated or used for hay production. A significant acreage has been developed for residential use. A small area is in woodland. Corn and soybeans are the principal row crops. Alfalfa is the principal hay crop. Native vegetation is upland hardwood forest.
DISTRIBUTION AND EXTENT: Loudoun County, Virginia. The series is of small extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Morgantown, West Virginia
SERIES ESTABLISHED: Loudoun County, Virginia, 2004.
REMARKS: Diagnostic horizons recognized in this pedon are:
Ochric epipedon - the zone from the surface of the soil to a depth of approximately 8 inches ( A and E horizons).
Argillic horizon - the zone from approximately 8 inches to a depth of 61 inches (Btx, Bt1, & Bt2 horizons).
Fragipan horizon - the zone from approximately 8 to 31 inches (Btx horizon).
Typic Fragiudults feature a fragipan in the profile and absence of low chroma mottles above the pan.
ADDITIONAL DATA: Mechanical and mineralogical analyses performed by the Loudoun County, Virginia, Department of Environmental Resources staff. Chemical analyses performed by Virginia Polytechnic Institute and State University staff. Lab numbers for this pedon are as follows: Loudoun County LC81-001 through 009 and VPI&SU--91-53-733 through 91-53-738.
108-016