The Battle for the Wetlands Wetlands were once considered wastelands, land that developers could pave over and build on and that no one would miss. Now, we know better. There are many different kinds of wetlands. They are commonly found at the mouths of rivers. Swamps are characterized by poorly drained mineral soils and by plant life dominated by trees.
Potholes are depressional wetlands found primarily in the upper Midwest.
They were formed by glaciers in prehistoric times. Bogs are characterized by deposits of spongy peat and extensive growth of evergreen trees and shrubs. A bog floor is usually covered by a thick carpet of moss. Fens are peat-forming wetlands that support diverse plant and animal communities. They are often covered by grasses, sedges, reeds, and wildflowers.