Basin marshes are large, shallow depressions with an outflow usually only during high water periods.  Depression marshes are also shallow depressions but smaller in size.  Their hydroperiod is around 200 days per year and their soils can sometimes consist of acidic peat (Florida Natural Areas Inventory, 1990).  The dominating shrubby vegetation can includes pockets of wax myrtle or coastal plain willow often in the center of the marsh and a surrounding band of St. John's wort with few to no trees.  Usually saw palmettos line the perimeter of the marsh at which point the marsh community ends and flatwoods begins (Gilbert et al., 1995).  Other common plants in both basin and depression marshes include panicum, common reed, cutgrass, southern watergrass, pennywort, Spanish needle, redroot, soft rush, American lotus, water primrose, arrowhead, coastal plain willow, saltbush, elderberry, spikerush, knotweed, buttonbush, dog fennel, St. John's wort, yellow-eyed grass, chain fern, willows, wax myrtle, swamp primrose, bloodroot, fire flag, pickerelweed, arrowheads, and bladderwort (Florida Natural Areas Inventory, 1990).

Fire is a frequent occurrence in Florida's marshes (Kushlan, 1990).  It helps to maintain the open community of basin and depression marshes by inhibiting the invasion of shrubs and trees and the buildup of an excessive amount of peat.  Fire normally occurs in these marshes at an interval between 1 and 10 years.  A marsh with a strictly herbaceous component will burn about every 1 to 3 years and one with mostly willow and buttonbush will burn about every 3 to 10 years.  During very dry periods, fire can burn the peat at the bottom of the marsh and convert the community into a marsh lake.  If fire is excluded from the community over a long period of time, the marsh could be converted the other way into a bog (Florida Natural Areas Inventory, 1990).

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