LOCATION TYGART WV+OH VA
Established Series
Rev. ART-FDC-JWB
04/2025
TYGART SERIES
The Tygart series consists of very deep, somewhat poorly drained soils formed in slackwater alluvium washed from soils on uplands. These soils are found on stream terraces in the central Appalachian Highlands. Saturated hydraulic conductivity is low. Slope ranges from 0 to 8 percent. At the type location, mean annual precipitation is about 1143 millimeters, and the mean annual air temperature is about 9.5 degrees C.
TAXONOMIC CLASS: Fine, mixed, semiactive, mesic Aeric Endoaquults
TYPICAL PEDON: Tygart silt loam - cultivated. (Colors are for moist soil.)
Ap--0 to 18 centimeters; grayish brown (10YR 5/2) silt loam; weak fine granular structure; friable; many fine roots; moderately acid; abrupt smooth boundary. (15 to 28 centimeters thick)
BA--18 to 25 centimeters; brown (10YR 5/3) silt loam; many fine prominent strong brown (7.5YR 5/8) soft masses of iron accumulation; weak fine subangular blocky structure; firm; common fine roots; moderately acid; clear smooth boundary. (7 to 23 centimeters thick)
Bt--25 to 46 centimeters; yellowish brown (10YR 5/4) silty clay loam; many medium distinct gray (10YR 6/1) iron depletions, and prominent strong brown (7.5YR 5/8) soft masses of iron accumulation; moderate medium subangular blocky structure; firm; slightly plastic, slightly sticky; common fine roots; few distinct clay films on faces of peds; few fine manganese concretions; strongly acid; clear, smooth boundary. (15 to 25 centimeters thick)
Btg--46 to 84 centimeters; gray (10YR 6/1) silty clay; many medium and coarse prominent strong brown (7.5YR 5/8) soft masses of iron accumulation; moderate medium and coarse subangular blocky structure; firm, slightly plastic, slightly sticky; few fine roots; few distinct clay films on faces of peds; common fine manganese concretions; strongly acid; gradual smooth boundary. (30 to 46 centimeters thick)
BCg--84 to 117 centimeters; gray (10YR 6/1) silty clay loam; many medium and coarse prominent yellowish brown (10YR 5/8) soft masses of iron accumulation; weak coarse subangular blocky structure; firm; few fine roots in cracks; many fine and medium manganese concretions; strongly acid; gradual smooth boundary. (8 to 46 centimeters thick)
Cg--117 to 165 centimeters; gray (10YR 6/1) silty clay; common medium prominent distinct strong brown (7.5YR 5/6) soft masses of iron accumulation; massive; very firm; very strongly acid.
TYPE LOCATION: Randolph County, West Virginia; about 0.7 mile southeast of the US Route 250 Tygarts Valley River Bridge, on Huttonsville Medium Security Prison Farm; USGS Mill Creek, West Virginia topographic quadrangle; latitude 38 degrees 42 minutes 11 seconds N. and longitude 79 degrees 58 minutes 07 seconds W.; NAD 1927.
RANGE IN CHARACTERISTICS: Solum thickness ranges from 90 to 150 centimeters. Depth to bedrock is more than 150 centimeters. Reaction ranges from moderately acid through very strongly acid in the upper part of the solum and strongly acid through extremely acid in the lower part of the solum and in the substratum. Rock fragments range from 0 to 3 percent in the solum.
The Ap horizon has hue of 10YR or 2.5Y, value of 4 or 5, and chroma of 2 or 3. Texture is silt loam or loam.
The BA horizon and the upper part of the Bt horizon have hue of 10YR or 2.5Y, value of 5 or 6, chroma of 3 through 8. The lower part of the Bt and BC horizons have hue of 10YR, 2.5Y, or is neutral, value of 5 through 7, chroma of 0 to 2. These horizons contain redoximorphic features. Texture is silty clay loam, clay loam, silty clay, or clay.
The C horizon has hues of 10YR, 2.5Y, or is neutral, values of 4 through 7, and chroma of 0 to 2. This horizon contains redoximorphic features. It is silty clay loam, silty clay or clay. Some pedons are gravelly below a depth of 125 centimeters.
COMPETING SERIES:
Wate series is the only other series in this family. Wate soils formed in alluvium derived from felsic crystalline rock. Soils in closely related families include the
Cavode,
Ivory,
Newflat, and
Wahee series. Cavode soils have more than 10 percent rock fragments of shale and sandstone in the lower part of the solum. Newflat and Wahee soils have thermic temperature regimes. Ivory soils have a frigid temperature regime.
GEOGRAPHIC SETTING: The Tygart soils formed in deposits of clayey slackwater alluvium washed from areas of mixed sedimentary lithology. They are found on stream terraces that are not subject to over-bank flooding. Slope gradients are 0 to 8 percent. The climate is humid temperate with average annual precipitation of 850 to 1250 millimeters and average annual air temperature of 9.5 to 13.3 degrees C. Frost free period ranges from 150 to 195 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the
Allegheny,
Berks,
Ernest,
Gilpin,
Monongahela,
Purdy,
Tyler,
Upshur,
Weikert, and
Zoar soils. The well drained Allegheny soils, moderately well drained Monongahela and Zoar soils, poorly and very poorly drained Purdy soils, and somewhat poorly drained Tyler soils which have a fragipan, are on associated terraces. The moderately deep Berks and Gilpin soils, well drained Upshur soils and shallow Weikert soils are in the nearby uplands. Ernest soils are moderately well drained soils on adjacent colluvial footslopes.
DRAINAGE AND PERMEABILITY: Somewhat poorly drained. Surface runoff class ranges from low to high. Saturated hydraulic conductivity is low.
USE AND VEGETATION: Most areas have been cleared and are used for growing pasture or field crops. The natural vegetation is chiefly hardwoods.
DISTRIBUTION AND EXTENT: Central Appalachian Highlands of West Virginia, Ohio, and Virginia. The series is of moderate extent. MLRAs: 124, 126, 127, 147.
SOIL SURVEY REGIONAL OFFICE (SSRO) RESPONSIBLE: Morgantown, West Virginia
SERIES ESTABLISHED: Berkeley County, West Virginia, 1963.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
1. Ochric epipedon - the zone from 0 to 25 centimeters (Ap and BA horizons).
2. Argillic horizon - the zone from 25 to 84 centimeters (Bt and Btg horizons).
3. Aquic conditions - the zone from 25 to 200 centimeters is subject to periodic
saturation.
4. Assignment of cation activity exchange class is based on data and classification of a soil in the same catena (Zoar series).
National Cooperative Soil Survey
U.S.A.