LOCATION SMOKEMONT NC+TN
Established Series
DJT-ARK; Rev. BPS
02/2011
SMOKEMONT SERIES
The Smokemont series consists of very deep, excessively drained soils that formed in coarse textured alluvium from igneous, high-grade metamorphic or low-grade metasedimentary geology. They are on nearly level to gently sloping flood plains of the Southern Blue Ridge mountains, MLRA 130B. Slopes range from 0 to 5 percent.
TAXONOMIC CLASS: Sandy-skeletal, mixed, mesic Fluventic Humudepts
TYPICAL PEDON: Smokemont gravelly sandy loam on a 3 percent slope in woodland. (Colors are for moist soil unless otherwise stated).
Oe--0 to 1 inches; moderately decomposed organic litter and roots.
A1--1 to 6 inches; black (10YR 2/1) gravelly sandy loam, brown; moderate fine to very coarse granular structure; very friable; common very fine and fine roots, many medium to very coarse roots; 20 percent gravel, 5 percent cobbles and 5 percent stones by volume; few fine flakes of mica; strongly acid; clear wavy boundary. (5 to 15 inches thick)
A2--6 to 11 inches; very dark grayish brown (10YR 3/2) very cobbly coarse sandy loam; weak fine to very coarse granular structure; very friable; few very fine and fine roots; common medium to very coarse roots;15 percent gravel, 10 percent cobbles, and 5 percent stones by volume; moderately acid; gradual wavy boundary. (8 to 20 inches thick)
C1--11 to 27 inches; brown (10YR 4/3) extremely gravelly sandy loam; massive; very friable; few medium to very coarse roots, 50 percent gravel, 10 percent cobbles, and 10 percent stones by volume; common fine flakes of mica; moderately acid; gradual wavy boundary.
C2--27 to 62 inches; brown (10YR 4/3) extremely gravelly loamy coarse sand; single grained; loose; 60 percent gravel, 10 percent cobbles, and 10 percent stones by volume; common fine flakes of mica; moderately acid.
TYPE LOCATION: Great Smoky Mountains National Park, North Carolina; 2.3 miles north of Smokemont Campground on access road along Bradley Fork Creek; 50 feet right of road. Smokemont USGS Topgraphic Quadrangle; latitude 35 degrees, 35 minutes, 14 seconds N; longitude 83 degrees, 19 minutes, 28 seconds W; NAD 27.
RANGE IN CHARACTERISTICS: Solum thickness is 8 to 20 inches and depth to bedrock is greater than 60 inches. Reaction is very strongly acid to neutral. Content of mica flakes ranges from none to many. Organic matter content is irregular with depth. The upper A or Ap horizons have less than 35 percent gravel and/or cobbles by volume. The lower part of the A horizon contains 35 to 60 percent gravel and cobbles by volume. Some pedons have an AC horizon that contains more than 35 percent gravel and cobbles by volume. The C horizon averages more than 35 percent rock fragments. Most often, they are dominantly gravel and cobbles with a small amount of stones. However, some areas may be dominated by stone size fragments. Some pedons have a thin C horizon that contains 15 to 35 percent by volume gravel and cobbles.
The A or Ap horizon, where moist, has hue of 10YR, value of 2 or 3, and chroma of 1 to 3; or hue of 7.5YR, value of 3, and chroma of 2. Dry value is less than 5.5. The upper A or Ap horizons are coarse loamy sand, fine sandy loam, or sandy loam in the fine-earth fraction. In some pedons, the lower part of the A horizon is coarse sandy loam, loamy sand or loamy fine sand in the fine-earth fraction
Some pedons have an AC horizon that has hue of 10YR or 7.5YR, value of 3, and chroma of 2 to 4. It is sand, coarse sand, coarse sandy loam, loamy sand, or loamy coarse sand in the fine-earth fraction.
A thin Bw horizon is present in some pedons. It has hue of 10YR or 7.5YR, value of 4 to 6, and chroma of 4 or 6. It is sandy loam or fine sandy loam in the fine-earth fraction.
The C horizon is multicolored or has hue of 10YR, value of 3 to 6, and chroma of 3 to 8; or hue of 2.5Y, value of 4 to 6, and chroma of 4 or 6; or hue of 7.5YR, value of 3 to 5, and chroma of 4 or 6. The C horizon is coarse sand, sand, loamy coarse sand, sandy loam or loamy sand in the fine-earth fraction
COMPETING SERIES: There are no other series in this family.
GEOGRAPHIC SETTING: Smokemont soils are on nearly level and gently sloping flood plains of fast flowing streams in the Southern Blue Ridge mountains, MLRA 130B. Elevation generally ranges from about 1,200 to 3,200 feet, but many range as high as 4,500 feet. The soils formed in loamy and sandy alluvium that contains a large amount of well rounded gravel and cobbles. Mean annual precipitation ranges from about 45 to 85 inches, and mean annual temperature ranges from 46 to 57 degrees F.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the
Biltmore,
Cullowhee,
Dellwood,
Ela,
Nikwasi,
Ostin,
Reddies,
Rosman,
Toxaway soils on flood plains and
Dillard and
Statler soils on low terrsaces. Biltmore soils are in a sandy particle-size class. Cullowhee soils are somewhat poorly drained. Dellwood, Ostin, and Smokemont soils are in a sandy-skeletal particle-size class. Reddies soils are coarse-loamy over sandy or sandy-skeletalparticle-size class. Ela, Nikwasi, and Toxaway soils are poorly and very poorly drained and occur in depressions and backwater areas. Rosman soils are in a coarse-loamy particle-size class and occur on flood plains of larger, or slower moving streams. Dillard and Statler soils have argillic horizons.
DRAINAGE AND PERMEABILITY: Excessively drained; the seasonal high water table is greater than 4 feet in winter and spring. The depth of the seasonal high water table is a function of the depth the stream channel and the distance from the stream channel. Runoff is slow. Permeability is moderately rapid in the A horizon and rapid or very rapid in the C horizon. Flooding frequency ranges from occasional to frequent. Duration of flooding is extremely brief or very brief.
USE AND VEGETATION: Most of the acreage is cleared and used for pasture and hayland. Some are in urban uses. Areas having stones and/or boulders on the soil surface are mainly in hardwood forest. Sycamore, yellow-poplar, river birch, eastern white pine, eastern hemlock, and red maple are the dominant trees. Common understory plants are rhododendron, ironwood, flowering dogwood, red maple, tag alder, greenbrier, and switchcane.
DISTRIBUTION AND EXTENT: Southern Blue Ridge mountains, MLRA 130B of North Carolina and Tennessee and possibly Virginia The series is of moderate extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Morgantown, West Virginia
SERIES ESTABLISHED: Great Smoky Mountains National Park, 2007.
REMARKS: The soil was formerly included with the Dellwood series. However, the Dellwood series has a seasonal high water table between 2 and 4 feet and is an Oxyaquic Dystrudepts.
Revisions made 9/07(HCD) adjusts OSD to reflect Lab Data.
The Smokemont series has the following diagnostic horizons and features:
Umbric epipedon - the zone from the mineral soil surface to a depth of 12 inches (A1 and A2 horizon)
Sandy-skeletal zone - the zone between 8 and 60 inches (A2, C1, and C2 horizon)
ADDITIONAL DATA:
MLRA: 130B
Revised 02/11-BPS: Taxonomic Classification -- 11th Keys, update competing and associated series, MLRA clarification
National Cooperative Soil Survey
U.S.A.