The vegetation in freshwater wetlands includes soft-stemmed plants, grasses, hardwood trees or mosses, among other things. The main producer in a freshwater marsh or pond are cattails which grow and thrive in the nutrient-rich waters. A marsh is always producing new grass as old grass dies. Detritus is dead and decaying plant or animal matter. Activity is ceaseless in a pond or small lake or marsh.
Water striders skate over the surface.
Dragonfly nymphs, which will soon change into swift, darting adults that climb the stems of cattails. A turtle plops off a log and begins to browse on plants. Countless small shrimplike scuds and clams strain their microscopic plant food from the water. They, too, then become food for small fishes that, in turn, are eaten by large fishes or by wading birds. The major purpose of this activity is for students to learn about freshwater marshes and reinforce their understanding of the concept of a food web.