LOCATION HORSETROUGH NC+TNEstablished Series
TAXONOMIC CLASS: Sandy-skeletal, isotic, frigid Typic Humaquepts
TYPICAL PEDON: Horsetrough flaggy fine sandy loam on a 15 percent slope at 4920 feet elevation--Forested. (Colors are for moist soil unless otherwise stated.)
Oe--0 to 1 inches; moderately decomposed leaves, twigs, roots, and other coniferous plant material.
A1--1 to 7 inches; very dark grayish brown (10YR 3/2) flaggy fine sandy loam; strong fine and medium granular structure; very friable; common very fine and fine, and many medium to very coarse roots throughout; 10 percent channers and 20 percent flagstones by volume; few fine flakes of mica; extremely acid; clear smooth boundary.
A2--7 to 13 inches; dark brown (10YR 3/3) extremely channery loamy coarse sand; weak very coarse granular structure; very friable; common medium and coarse roots throughout; 70 percent channers and 10 percent flagstones by volume; few fine flakes of mica; very strongly acid; clear smooth boundary. (Combined thickness of the A horizon is 10 to 20 inches.)
BCg--13 to 28 inches; dark gray (10YR 4/1) extremely channery coarse sand; single grain; loose; common spherical 2.5/N manganese nodules, masses and veins throughout, and coatings on rocks; 68 percent channers and 10 percent flagstones by volume; few fine flakes of mica; very strongly acid; clear smooth boundary.
C1--28 to 33 inches; gray (10YR 5/1), brown (10YR 5/3), and strong brown (7.5YR 5/8) channery loamy sand; single grain; loose; 18 percent channers by volume; few fine flakes of mica; strongly acid; abrupt wavy boundary.
C2--33 to 40 inches; light olive brown (2.5Y 5/3) fine sandy loam; massive; very friable; 10 percent channers by volume; few fine flakes of mica; strongly acid; abrupt wavy boundary.
2C--40 to 46 inches; multicolored saprolite that crushes to loamy coarse sand; massive; 14 percent channers by volume; few fine flakes of mica; strongly acid; clear wavy boundary.
2Cr--46 to 62 inches; weathered metasandstone bedrock
TYPE LOCATION: Haywood County, North Carolina; Great Smoky Mountains National Park, at Polls Gap trailhead, Balsam Mountain Road; 1,400 feet northeast of parking area. USGS Bunches Bald Topographic Quadrangle: latitude 35 degrees, 33 minutes, 52 seconds N.; longitude 83 degrees, 09 minutes, 06 seconds W.; NAD27.
RANGE IN CHARACTERISTICS: Depth to paralithic contact is 40 to 60 inches or more. Reaction ranges from ultra acid to strongly acid throughout. Content of mica flakes is few or common throughout. Rock fragment content averages 35 to 80 percent in the particle-size control section, and less than 60 percent in underlying horizons.
The A horizon has hue of 7.5YR or 10YR, value of 2 or 3, and chroma of 1 to 3. It is fine sandy loam, sandy loam, loamy sand, loamy coarse sand, or sand in the fine-earth fraction.
The BCg horizon has hue of 10YR or 2.5Y, value of 3 to 5, and chroma of 1 or 2. Texture is loamy sand, loamy coarse sand, coarse sand, or sand in the fine-earth fraction.
The C horizon has hue of 10YR or 2.5Y, value of 4 to 6, and chroma of 1 to 8. Texture is loamy sand, loamy coarse sand, coarse sand, or sand in the fine-earth fraction. Some subhorizons may have a texture of fine sandy loam or sandy loam in the fine-earth fraction.
The 2C horizon is multicolored or has hue of 5YR to 2.5Y, value of 4 to 6, and chroma of 1 to 8. Texture is loamy sand, loamy coarse sand, or sand in the fine-earth fraction. Some subhorizons may have a texture of fine sandy loam or sandy loam.
The 2Cr horizon is weathered metasedimentary bedrock such as metasandstone, phyllite, or slate. It is partly consolidated but can be dug with difficulty with a spade.
COMPETING SERIES: There are no competing series in this family.
GEOGRAPHIC SETTING: Horsetrough soils are on gently sloping to moderately steep slopes along drainageways in coves at high elevations in the Blue Ridge (MLRA 130). Slopes are between 2 and 30 percent. Elevation ranges from about 4500 to 6400 feet. These soils formed in colluvium and the underlying residuum weathered from metasedimentary rocks such as metasandstone, phyllite and slate. Mean annual temperature ranges from 35 to 45 degrees F., and mean annual precipitation ranges from about 60 to 100 inches. Moist atmospheric conditions are prevalent and fog is common in these high mountain areas.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Anakeesta, Breakneck, Cataloochee, Chiltoskie, Guyot, Heintooga, Luftee, Oconaluftee, and Pullback series. All of these soils are well drained.
DRAINAGE AND PERMEABILITY: Poorly drained; very little runoff where forest litter has not been disturbed or only partially removed; medium to very rapid runoff where litter has been removed; moderately permeability.
USE AND VEGETATION: Nearly all of this soil is in forest. Common trees are northern red oak, black birch, American beech, yellow birch, black cherry, sugar maple, eastern hemlock, yellow buckeye, red spruce, and fraser fir. In many areas the trees are stunted due to wind and ice damage and a "windswept phase" is recognized. The understory species are serviceberry, striped maple, American chestnut sprouts, red maple, pin cherry, rhododendron, mountain-laurel, silverbell, blueberry, and flame azalea. Common forbs are hay-scented fern, wood fern, New York fern, Solomon's seal, yellow mandarin, and trillium.
DISTRIBUTION AND EXTENT: Southern Blue Ridge (MLRA 130B) of North Carolina and Tennessee, and possibly Virginia. This series is of small extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Morgantown, West Virginia
SERIES ESTABLISHED: Great Smoky Mountain National Park, 2007
REMARKS: Horsetrough soils are mapped in complex with Chiltoskie and Heintooga soils. Drainageways in coves that Horsetrough soils occupy are normally too narrow to delineate as a consociation map unit. However, these areas represent unique habitat for certain aquatic species.
Revisions made 9/07(HCD) adjusted OSD to reflect Lab Data.
The Horsetrough series has the following diagnostic horizons and features:
Umbric epipedon - the zone from the mineral soil surface to a depth of 13 inches (A1 and A2 horizons)
Paralithic contact - weathered bedrock contact at 46 inches (upper boundary of the 2Cr horizon).
Isotic mineralogy class - In more than one-half of the control section, a 1500 kPa water to clay ratio of 0.6 or more and a pH in NaF solution of more than 8.4.
ADDITIONAL DATA: Lab data from NSSC-SSL sample S00NC-087-004.
NASIS Site ID: 114006
NASIS Pedon ID: 114880
NASIS User Pedon ID: Horsetrough OSD
NASIS DMU ID: 411076
MLRA = 130