A wetland is not just ground that is wet. Certain hydrologic or water-containing soils must be present along with wetland plants and trees.
Wetlands are transitional zones between uplands – or an area of land that lies above the level where water flows or where flooding occurs – and bodies of water, sometimes where groundwater comes to the surface, according to the Chicago-based nonprofit organization Wetlands Initiative.
Commonly, those soils would be known as silty clay or organic soils like muck or peat made of dead and dying plant matter, said Scott Fetters, fish and wildlife biologist for the Northeast Indiana Habitat Restoration office of the U.S. Fish and Wildlife Service.
Plants are hydrophytes, or plants specially adapted to grow in saturated soils. Some of those include bull rushes, arrowhead, sedges and blue flag iris. Many of the cattails seen in wetland areas are an invasive species, Fetters said.
Wetland restoration is best carried out by professionals, said Chris Sebastian, Ducks Unlimited's spokesman for the Great Lakes Atlantic Region.
“It takes really big construction, earth moving projects for wetland restoration. Even enhancing a wetland takes expertise and equipment. There are contractors we work with,” Sebastian said.
The greatest threat to wetlands “is always going to be human involvement and development,” Sebastian said. “Another huge issue is climate change whether you believe it's human-driven or not.”
Frequent and heavy rainfalls threaten completed enhancement or restoration projects.
An example would be an 85-acre farm field restored and then surrounded by berms.
“We allow that area to flood and drain and flood naturally, keeping surrounding properties intact. If a big flood comes through, it really has the potential to damage, wipe out part of these berms and dikes we've used to establish wetlands on that property,” Sebastian said.
Types of wetlands in the Midwest include marshes, sedge or wet meadows, wet prairies, fens and seeps, bogs, and forest and shrub swamps, according to the Wetlands Initiative.