LOCATION STUMPTOWN VA+MD
Established Series
Rev. RSW-JHE-DDR
02/2022
STUMPTOWN SERIES
Soils of the Stumptown series are moderately deep well drained with moderately rapid permeability. They formed partly in slope creep and partly in residuum that weathered from interbedded quartzite, quartz muscavite schist and phyllite of the Blue Ridge Anticlinorium. Slopes range from 2 to 50 percent. Mean annual precipitation is about 40 inches, and mean annual temperature is about 55 degrees F.
TAXONOMIC CLASS: Loamy-skeletal, mixed, active, mesic Inceptic Hapludults
TYPICAL PEDON: Stumptown very flaggy loam on 15 to 25 percent slopes in a mixed hardwood forest dominated by chestnut oak. (Colors are for moist soil)
O--0 to 1 inch; partially decomposed hardwood leaves and twigs.
A--1 to 3 inches; dark grayish brown (10YR 4/2) very flaggy loam; moderate fine granular structure; very friable; many fine medium and coarse roots; 45 percent quartzite flagstone; very strongly acid; clear smooth boundary. (1 to 4 inches thick)
E--3 to 13 inches; light yellowish brown (10YR 6/4) very flaggy loam, moderate fine granular structure; very friable; many fine, medium and coarse roots; 45 percent quartzite gravel and flagstone; few fine mica flakes; very strongly acid; clear smooth boundary. (2 to 15 inches thick)
Bt--13 to 21 inches; brownish yellow (10YR 6/6) very flaggy clay loam; common medium distinct strong brown (7.5YR 5/6) streaks and mottles; weak fine and medium subangular blocky structure. Friable; common fine, medium and coarse roots; few thin clay films on ped faces; many fine mica flakes; 45 percent quartzite gravel and flagstone; very strongly acid; clear irregular boundary. (3 to 12 inches thick)
C--21 to 28 inches; varigated in shades of brown, yellow, red and white; extremely flaggy sandy loam; massive; very friable; many fine and medium roots; many fine mica flakes; 60 percent quartzite flagstones; very strongly acid; clear irregular boundary.
2Cr--28 to 34 inches; interbedded quartzite and partially weathered quartz muscovite mica schist with loamy soil material in rock crevices.
2R--34 inches; bedrock of quartzite and quartz muscovite mica schist.
TYPE LOCATION: Prince William Co., Virginia; in Bull Run Mountain Estates about 100 feet west of Jackson drive and about 200 feet north of Sumney drive.
RANGE IN CHARACTERISTICS: Solum thickness ranges from 12 to 30 inches. Depth to 2 Cr horizon is from 20 to 40 inches and depth to bedrock is from 20 to 40 inches. Rock fragments of quartzite gravel, cobbles, and flagstones ranges from 35 to 60 percent in the solum and up to 90 percent in the C horizon. From 0 to 15 percent of the surface area is covered with stones and boulders up to 36 inches in diameter. This soil is very strongly acid or strongly acid, unless limed.
The A horizon has hue of 7.5YR or 10YR, value of 3 through 5 and chroma of 1 through 3. Texture is loam or sandy loam in the fine earth fraction.
The E horizon has hue of 7.5YR or 10YR, value of 6 or 7 and chroma of 3 through 6. It is loam, or sandy loam in the fine earth fraction.
The Bt horizon has hue of 7.5YR or 10YR, value of 5 or 6, and chroma of 4 through 6. Mottling in shades of red and yellow is common in the lower part of some pedons. It is loam, sandy clay loam, or clay loam in the fine earth fraction.
The C horizon is variegated in shades of yellow, brown, red and white. It is loam, sandy loam, or sandy clay loam in the fine earth fraction.
The 2Cr is interbedded quartzite and partially weathered quartz muscovite schist.
The 2R is hard bedrock interbedded quartzite and quartz muscovite schist.
COMPETING SERIES:
Occoquan is the only series in the same family. Occoquan soils weathered from granite gneiss and schist of the
Piedmont Plateau and depth to hard bedrock is more than 60 inches
GEOGRAPHIC SETTING: Stumptown soils are on ridges, ridge points and convex sideslopes of the Northern portion of the Blue Ridge Anticlinorium. These soils developed partly in local creep and partly in residuum that weathered from interbedded quartzite and quartz muscovite schist. Slope ranges from 2 to 50 percent. Mean annual precipitation ranges from 36 to 44 inches and mean annual temperature ranges from 50 to 59 degrees F.
GEOGRAPHICALLY ASSOCIATED SOILS: The dominantly associated soils are the
Airmont and Wevertown soils; also on lower landscape positions the Stumpton,
Braddock,
Thurmont and
Trego soils are associated at a lesser extent. All of these soils have a thicker solum.
DRAINAGE AND PERMEABILITY: Well drained; slow to very rapid surface runoff and moderately rapid permeability.
USE AND VEGETATION: Except for a few small areas used for lawns, recreational areas and garden plots most of the acreage is in hardwood and pine forest. In some places it is used for residential development. Woodland vegetation is oak-hickory type forest and is dominantly Chestnut Oak.
DISTRIBUTION AND EXTENT: Northern Virginia, Maryland, and southern Pennsylvania. Moderate extent; 5,000 acres in northern Virginia.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Morgantown, West Virginia
SERIES ESTABLISHED: Prince William County, Virginia, 1985.
REMARKS: This soil has previously been included in Buckingham series, a Pennsylvania soil now on the inactive list. Lab data from VPI&SU lab. Diagnostic horizons or features recognized in this pedon are:
1. Ochric epipedon-from mineral surface to 13 inches (A and E horizons)
2. Argillic horizon-from 13 to 21 inches (Bt horizon)
3. Paralithic contact at 28 inches
4. Lithic contact at 34 inches
5. Discontinuity at 28 inches
02/2022 revision: O had 1 to 0 inch depths, corrected to be 0 to 1 in horizon depths then added 1 inch to all horizon depths throughout the typical pedon.
MLRA=148, 149A
SIR=VA0073
REVISED=MHC, 7/25/95
National Cooperative Soil Survey
U.S.A.