A marsh is a type of wetland which is distinguished from other wetland varieties by having an assortment of grasses, reeds, and sedges, without large bushes and tall trees. The height of standing water in a marsh can range, depending on the location and the season, but the mud or clay that forms the base of the marsh is always heavily saturated. A marsh can be salt or fresh water, and often has large spaces of open water which are heavily colonized by birds. Like other wetlands, a marsh provides vital habitat to many plant and animal species as well as protecting neighboring areas of land from flooding, and in the case of saltwater marshes, excessive salination.
In drier seasons, the level of standing water in a marsh may be as low as six inches (15 centimeters). In more wet times, the water can rise to three feet (one meter) or more, if flooding becomes excessive. Therefore, the plants that live in marshes are adapted to flexing water levels, and to having thoroughly saturated roots. In some marshes, water is deep year round, supporting communities of cattails, tall reeds, wild rice, and water lilies. More shallow marshes have sedges, grasses, rushes, and short reeds.
Plants adapted to the marsh environment tend to be very hardy. They have broad leaves, because their state of constant saturation means that the plants do not need to concern themselves with moisture loss. The leaves help the plants absorb sunlight and photosynthesize their energy. Many marsh plants also have hollow or spongy stems to prevent rot and move energy around the plant. These broad spaces also oxygenate the water and soil of the marsh, creating a healthy environment for fish and other animals to thrive in.
Most marshes also have a large population of birds adapted to aquatic life. Ducks and geese are very common, as are flamingos, herons, egrets, and other long legged birds which have ample sources of food in the marsh environment. Beavers and muskrats can also be found in many marshes, and a delicate balance between all the plant and animal species that share the marsh is usually maintained.
The protection that marshes provide to neighboring lands has led to many government sponsored efforts around the world to preserve and restore marshes, along with other wetlands. Animal conservation organizations also participate, to retain the unique habitat provided by marshes. In many areas with well-maintained marshes, walking paths have been built so that people can enjoy the beauty of the marsh as well. Please use care when exploring a marsh, as it is a delicate environment that can easily be damaged by garbage, loose dogs, and other acts of carelessness. It is also very easy to get lost in a marsh, or stuck in a deep area of mud or clay, so always explore with others.