Basin Marsh

Basin Marsh - (synonyms: prairie, freshwater marsh).

Basin Marsh is characterized as an herbaceous or shrubby wetland situated in a relatively large and irregular shaped basin. Typical plants include common reed, panicum, cutgrass, southern watergrass, pennywort, Spanish needle, redroot, soft rush, American lotus, water primrose, arrowhead, coastal plain willow, saltbush, elderberry, spikerush, knotweed, buttonbush, and dog fennel. Typical animals include two-toed amphiuma, lesser siren, greater siren, cricket frog, green treefrog, bull frog, pig frog, leopard frog, alligator, eastern mud snake, green water snake, banded water snake, striped swamp snake, black swamp snake, great blue heron, great egret, snowy egret, little blue heron, tricolored heron, bald eagle, and northern harrier.

Basin Marshes usually develop in large solution depressions that were formerly shallow
lakes. The lake bottom has slowly filled with sediments from the surrounding uplands and with peat derived from plants. Thus, the soils are usually acidic peats. The hydroperiod is generally around 200 days per year. Open areas of relatively permanent water within the marsh, with or without floating aquatic vegetation, are considered to be Marsh Lakes (See Lacustrine Natural Communities).

Fire maintains the open herbaceous community by restricting shrub invasion. The
normal interval between fires is 1 to 10 years, with strictly herbaceous marshes burning about every 1 to 3 years, and those with substantial willow and buttonbush having gone 3 to 10 years without fire. Fires during drought periods will often burn the mucky peat and will convert the marsh into a Marsh Lake.

Basin Marshes are associated with and often grade into Wet Prairie or Lake communities. They may eventually succeed to Bog, if succession is not reversed by a muck fire. Many of the plants and animals occurring in Basin Marshes also occur in Floodplain Marsh, Slough, Swale and Depression Marsh. Large examples of the Depression Marsh, in fact, may be very difficult to distinguish from small examples of Basin Marsh.

Normal hydroperiods must be maintained, or Basin Marsh vegetation will change.
Shortened hydroperiods will permit the invasion of mesophytic species, while longer
hydroperiods will convert marsh into lake. Fire is also necessary to control hardwood
encroachment. However, fires during droughts should be avoided to reduce the possibility of a muck fire. Many sites have been degraded by pollution or drained for agricultural uses.

• Source: Florida Natural Areas Inventory and Florida Dept. of Natural Resources. 1990. Guide to the natural communities of Florida. Florida Natural Areas Inventory and Florida Dept. of Natural Resources, Tallahassee, FL. iv, 111 p.