Soil Survey of Lincoln County, West Virginia - Soil Data Mart - US ...

Time
Soil Survey of Lincoln County, West Virginia
The length of time that parent material has been in place and exposed to the active
forces of climate, as well as plant and animal life, strongly influences the nature of the
soil. The time required for a soil to form depends on the other soil-forming factors. For
example, less time is required for a well developed soil to form in a warm, moist
climate than in a cool, dry climate if all other factors are the same.
Most of the soils in Lincoln County are relatively young. As weathering processes
act upon the exposed rocks, mostly on points and ridges, the residue is subjected to
the forces of water and gravity. Weathered soil material and rock fragments are
carried downslope and deposited as colluvium. As the colluvium accumulates, the
heavy weight of the colluvium, steep angle of slope, and water seeps along bedrock
tend to move the mass very slowly and irregularly downslope onto the flood plain. Soil
is removed from the valleys by the action of the streams. Thus, the valleys slowly
become wider.
Relatively young soils on ridgetops and side slopes have developed soil structure
and a B horizon that is well defined by color, but they have little illuvial clay
accumulation. Such soils in Lincoln County are classified as Typic Dystrudepts. They
include the Hazleton soils.
Some soils on the less sloping hillsides have a thick, well defined B horizon that
has a significant accumulation of illuvial clay. Examples are the Shelocta soils, which
are classified as Typic Hapludults.
Immature soils have little profile development and have retained many of the
characteristics of the original parent material. In Lincoln County, the immature soils
are primarily on flood plains where the seasonal high water table and deposition of
fresh materials prevent the development of distinct soil horizons. They include the
Yeager soils. Immature soils are also on side slopes where runoff and geologic
erosion prevent profile development.
The older soils on terraces, such as those in the Cotaco and Allegheny series,
formed in water-deposited material but do not currently receive a significant amount
of deposition. They are leached and weathered, and the content of illuvial clay
depends upon their position in relation to the stream and in situ weathering of primary
and secondary minerals.
Topography
Lincoln County is in the central part of the Appalachian Basin. The Cumberland
Plateau and Mountains and Central Allegheny Plateau are physiographic sections in
the county. These physiographic sections contain deeply dissected sandstone,
siltstone, and shale plateaus with some layers of calcareous rocks in areas of the
Central Allegheny Plateau. The rocks are of various hardness and, together with the
interbedded coalbeds, have weathered to form a benched landscape on the uplands
with a dendritic drainage pattern. The topography of these sections has been
described in further detail in the section entitled “General Nature of the County.”
The effect that topography has on the soils in Lincoln County is mainly through its
influence on the amount of water moving through the soil, the amount and rate of
runoff, and the rate of erosion. Large amounts of water have moved through the
gently sloping and strongly sloping soils in the county; such water movement favored
the formation of deep soils that have a well developed profile. On steep and very
steep hillsides, less water moved through the soils and more water ran off the
surface. The soil material was washed away almost as rapidly as it formed. As a
result, the soils on many of the steeper hillsides are shallower over bedrock than the
soils on the more gentle slopes.
Natural differences in elevation and shape of landforms account for some
differences in the kinds of soils that formed in the survey area. The soils formed in
residuum are mostly at the higher elevations, ridges, and points. Most soils on
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