Soils

The five major factors in the formation of soils are climate, living organisms, parent material, topography, and time. Climate and living organisms, particularly vegetation, are the active forces. Their effect on parent material is modified by topography and by the length of time the parent material has been in place. The relative importance of each factor varies from place to place.

Climate is important in the formation of soils because it influences the weathering of rocks and minerals. Weathering is more rapid under a warm, humid climate than it is under a cold or dry climate. Since the climate is fairly uniform throughout the county, there are no significant differences among soils of the river corridor caused by climate alone. In addition, precipitation and length of growing season influence the type and abundance of vegetation.

Native plants have been and continue to be a major influence on the development of soils. Trees and other plants take up minerals from the soil and store them in their roots, stems, and leaves. When trees shed their leaves or needles or when plants die and decay, the plant nutrients are returned to the soil and are used by other plants. Soil development is also affected by plant roots. Roots penetrate soil material to various depths, generally increase soil porosity, and break course fragments such as stones. Organic acids produced by plants or released during the decay of plant material react on basic minerals contained in the parent material.

Differences in slope, especially in combination with differences in the position on the landscape, have a significant influence on the kind of soil that develops from a given parent material. Soils in steep areas where erosion is high tend to be shallow. In flat areas, soils are usually thick and well developed.

The varying characteristics of soils are important for two reasons: (1) They influence the type and abundance of vegetation; (2) They limit the possible uses of land. The following chart and map depict the soil series and associations found within the watershed. High erosion rates and stony material are the main limitations to the soils in the Deep Creek Lake watershed.