Backslope – a hillslope profile position that forms the steepest and generally linear, middle portion of the slope. Backswamp – marshy or swampy, depressed areas of flood plains between natural levees and valley sides or terraces Calcareous – the presence of calcium carbonate in the soil parent material within the rooting zone; relatively alkaline Claypan – a dense, compact, slowly permeable layer in the subsoil having much higher clay content than the overlying material Chert – hard, extremely dense or compact crystalline sedimentary rock, consisting dominantly of interlocking crystals of quartz Cliff – a significant vertical, or near vertical, rock exposure Dolomite – a type of sedimentary rock that is a carbonate mineral composed of calcium magnesium carbonate Drainageway – the upper most reach of a stream channel system characterized by little meandering Dry – a site where soil moisture is limiting during the growing season; low available water capacity Dune – a low mound, ridge, bank or hill of loose, wind-blown sand Exposed – steep, south and west-facing slopes, which are warmer and drier than other slope aspects Flatwoods – a type of woodland that occurs on soils with a root restricting subsoil layer within 20 to 30 inches, resulting in very slow runoff and ponding that remains saturated for most of the winter and early spring months but dries out and becomes very dry in the summer months; plants that grow there must be adapted to both conditions Floodplain – the nearly level plain that borders a stream and is subject to inundation under conditions Footslope – a hillslope position at the base of a slope where hillslope sediment (colluvium) accumulates Forest – a vegetative community dominated by trees forming a closed canopy and interspersed with shade-tolerant understory species Fragipan – a dense, brittle subsoil horizon that is extremely hard and compact when dry Glade – open, rocky, barren vegetative community dominated by drought-adapted forbs and grasses, typically with scattered, stunted woody plants Igneous –bedrock formed by cooling and solidification of magma. Granite and rhyolite are typical igneous bedrocks in Missouri Limestone – a type of sedimentary rock composed largely of calcium carbonate
Shallow – a site with bedrock within 20 inches of the surface Shoulder – the slope profile position that forms the convex surface near the top of a hill slope; it comprises the transition zone from summit to backslope Sinkhole – a closed, circular or elliptical depression, commonly funnel-shaped, characterized by subsurface drainage and formed either by dissolution of the surface of underlying bedrock or by collapse of underlying caves within bedrock Summit – the top or highest area of a hillslope Swale –shallow, closed depressions irregularly spaced across a floodplain or terrace with an irregularly undulating surface. Swamp – an area of low, saturated ground, intermittently or permanently covered with water, and predominantly vegetated by shrubs and trees. Talus – rock fragments of any size or shape (usually coarse and angular) derived from and lying at the base of a cliff or very steep rock slope. Terrace – a step-like surface, bordering a valley floor that represents the former position of a flood plain Till – dominantly unsorted and unstratified soil material deposited directly by a glacier Ultic – soil that has a clay-dominated subsoil (argillic horizon) with low amounts of bases such as calcium, and were typically formed under woody vegetation Upland – a general term for the higher ground of a region, in contrast with a low-lying, adjacent land such as a valley or floodplain Wet – a somewhat poorly, poorly or very poorly drained site that has an oversupply of moisture during the growing season Woodland – a highly variable vegetative community with a canopy of trees ranging from 30 to 100 percent closure with a sparse midstory and a dense ground flora of grasses, sedges and forbs