Flat lowlands with no canopy, dominated by grasses, rushes, scattered palmetto and low herbaceous plants. One of the richest seasonal wildflower communities. Fire dependent. Wet prairies -- large wet prairie systems can be found as a mosaic in the wetter parts of flatwoods, but this kind of community also forms the upper zones (ecotones) of marhes, lake and pond edges, and edges around cypress domes. Wet prairie is the least frequently flooded type of marsh, with a shorter hydroperiod (days of standing water) than other marsh systems in a typical year. Well-designed ponds, lake edges and marshes similar to natural systems will have slopes contoured as gently as 1:20 that will support wet prairie vegetation. Wet prairies have a great diversity of sedges, grasses and wildflowers, with very few shrubs, and possibly a few scattered trees. The gently sloping sandy soils are usually acid and low in organic matter, and can vary from dry to saturated and flooded during the year. The higher parts of the wet prairies may also support different plants than the wetter zones. Dry prairies -- Seldom flooded lands with sand substrate. Grasses dominate, with some herbs and shrubs present.