Unfortunately, for centuries some wetlands, especially marshes and swamps, have had a bad image Such areas harbored dreaded diseases during pioneer times. Old World folklore told of the dark mystery of bogs. Who would want such a feature on their land? Water has also been intensely managed in the last 150 years. Illinoisans have extensively modified the environment to make water go where they wanted. Wetlands have been eliminated by drainage and filling. Rivers and streams have been rerouted, deepened, and dammed to suit human purposes.

Anyone with an inkling of interest in nature need only visit a marsh or a swamp on an April morning or evening to hear a remarkable concert of songbirds or frogs. Or you could don waders
in November to visit a cattail marsh and see a diversity of waterfowl. See Table 5.1 for information on the attributes of selected wetland wildlife species.

The term wetland has historically been defined in many ways, confusing scientists and the public alike. In 1979 the U.S. Fish and Wildlife Service developed a classification system to describe all water habitats in the U.S. The system, classifying wetlands and deepwater habitats, was subsequently adopted by Illinois scientists.

Illinois water habitats are classified in three categories:

The terms wetland and aquatic habitat are used interchangeably in this chapter, with wetland being a generic term for water habitat. Sedge meadows generally are dominated by a mixture of sedge plants. These meadows are not permanently flooded but are located in areas of frequently damp soil conditions. Marshes may have permanent or seasonal water and usually contain both emergent (growing in and above the water) and submergent (growing under the water) herbaceous vegetation. Forested wetlands in Illinois are known by such names as swamps, floodplain forests, and bottoms. Most of our forested wetlands are composed of trees that can survive short, frequent periods of flooding, such as silver maple, cottonwood, and green ash. Southern Illinois, however, has a unique type of forested wetland composed of stands of baldcypress and water tupelo, which are noted for their ability to tolerate long periods of inundation.

While lake and river habitats are discussed in this chapter, the primary focus is smaller aquatic habitats that landowners can create and manage. Also addressed are the habitats flanking rivers and streams (riparian habitat), which landowners can significantly impact. Floodplain forests, which are also defined as wetlands due to their periodic inundation, are discussed briefly, but more specifics can be found in chapter 4.