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Marshland, an area absent of trees where the water table is at, above, or just below the surface of the ground. The predominant plant life includes grasses, reeds, sedges, and cattails, all typifying emergent vegetation, leaves above water and roots buried in sediment below the water surface. Marshes are freshwater as well as salt. Freshwater marshes are typically found at the shallow areas of lakes and slower rivers, forming when a pond or lake becomes filled with silt and sediment. Salt marshes are found in coastal tidal flats where there is no tidal disturbance, and inland salt marshes can be found at the edges of salt lakes. A marsh is characterized by it's plant composition, species diversity, and productivity which affect the supply of nutrients, movement of water, and the type and composition of sediment found within. All these components directly affect surrounding ecosystems.

Photo: Brother Alfred Brousseau

Marshes have a life cycle which is based on drought and the feeding habits of muskrats. During dought, the cycle starts with a relatively dry or muddy land base where seeds from aquatic plants germinate. When rains come and the marsh fills with water, the plants grow densely. Muskrats will then eat large amounts of the emergent vegetation creating vast open areas in the marsh which allows submerged and floating plant life to thrive. Drought comes and the cycle starts over.

Plant Life
Some marshes, such as the Everglades saw-grass wetlands, and salt marshes are flooded twice a day by tides, the region is dominated by one or two species of emergent vegetation. In marshes where the water flows in channels, only flooding during high precipitation, the irregular pattern of sediment deposits creates conditions in which a variety of wetland plants can thrive. Deep marsh water gives aquatic submerged plants and floating plants such as pond lilies an ideal environment. Shallow marsh waters are where you will find reeds, grasses and wild rice, and in even shallower water, sedges, bulrushes, and cattails.

Eventually sediments and organic deposits will raise the land base of a marsh, creating islands and large land areas in the water. Aquatic vegetation cannot survive on a dry land mass and is replaced by shrubs and eventually by a terrestrial ecosystem of forest trees and upland grasses.