ZOOMED SOIL TYPES
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Soils are created in a zone of interaction between the parent material, or glacial till in most areas of the Catskills, and the vegetation on the ground surface. If the Catskills had not been glaciated, the soil parent material would have been the weathered sedimentary bedrock. Mineral matter from the underlying glacial till combines with organic material from vegetation and burrowing animals to produce soil. The gravel, sand, silt, and clay components of the till affect soil quality and vegetational uptake up water and nutrients. Decomposing bacteria and other organisms break down organic material into forms that are usable by plants and other organisms, and eventually mixes with mineral material. Soil depth is generally no deeper than the depth of the deepest plant roots, even though the parent material might extend much deeper in to the earth. Much of the till parent material in the Catskills is very hard and compact, and referred to as ‘fragipan’. The oldest soils can only be slightly younger than the parent material. Therefore, Catskill soils are very young in terms of the geologic timescale because most of the glacial till parent material was deposited only about 15,000 years ago.

Soil types are generally designated by the amounts of organic and inorganic materials that they are comprised of. Differences in soil type occur horizontally across a landscape, but also vertically in varying soil layers, or ‘horizons’. The most common soil ‘order’, or group of common soil types, in the Catskills is the ‘Inceptisol’ order. Soils in this order reflect the young, glaciated origin of most Catskill soils. Other soil orders found in the region include flood deposits, or ‘Entisols’ along the major creeks, and ‘Histosols’ in wet bogs and swamps. Inceptisols are further divided into sub-orders based on characteristics such as drainage and their association with fragipan parent till. Further divisions are derived based on soil depth, moisture content, pH, organic content, etc. Soils that are deep and have a significant amount of clay, silt, and organic matter content, will generally support more productive vegetation.