It has deep, fine-textured soils formed in silt and clay, ranging from dry to wet. The kinds of plants vary based on the amount of moisture. Midewin NTP a. Dry Prairie. Grasses are usually less than a meter tall. These prairies contain surface water in winter and spring, and are used by a variety of migrating waterfowl and wading birds.
Soils are coarse-textured sands or sandy loam and range from dry to wet.
Wet sand prairie is similar to wet prairie in the kinds of plants that are present. Some characteristic plants are little bluestem and prairie dropseed. This type is the most restricted in Illinois. It occurs where dolomite, a type of sedimentary rock, is less than 1.5 m from the ground surface. These soils are subject to seasonal variations in soil moisture because the bedrock impedes drainage, but the shallow soils have little water holding capacity.