The coastal landscape is composed of a matrix of interrelated plant communities distinguished by their proximity to the coast, soil types, and vegetation. Here we describe natural uplands (beach primary dune, backdune, coastal grassland and coastal scrub), wetlands (interdunal swale and salt marsh), and a novel, human-created system (constructed berms). All of these communities except coastal scrub and salt marsh are generally not maintained by fire. Coastal scrub has a long fire interval with very intense burns that consume the canopy. Below is more information on each community type.
Dry (xeric) sandy soils in active sand and sediment exchange with the Gulf of Mexico. This community is characterized by little to no vegetation and wave deposited wrack (organic matter from Gulf). Many public access beaches have wrack removed, disturbing natural dune building processes.
Xeric sandy soils are composed of dune building grasses including sea oats (Uniola paniculata), bitter panicgrass (Panicum amarum), and gulf bluestem (Schizachyrium maritimum), as well as early pioneer species including seacoast marshelder (Iva imbricata), gulf croton (Croton punctatus), beach morning-glory (Ipomoea imperati) and sea beach evening primrose (Oenothera humifusa). This is the area of dune formation that occurs between the beach and/or the constructed berm and the back dune field.
Xeric soils of various compositions that may include shells and other foreign dredge material are constructed into dune lines running parallel to the coast and generally vary in height from a few to several feet tall. These constructed berms frequently occur on our coastline. The only berm free areas are located on protected lands or in areas where previously constructed berms were blown out from storms or other periods of high turbulence. Constructed berms are built with the intention to protect coastal infrastructure and are occasionally mistaken for "coastal restoration". Unfortunately, they offer very little ecological value. They are typically planted with a monoculture of sea oats (Uniola paniculata) or bitter panic (Panicum amarum). These areas are ecologically inhospitable and therefore, only the toughest coastal plants and urban weeds are generally able to persist. The data remains inconclusive on the efficacy of constructed berms for long term coastal protection.
Xeric sandy soils with little sand or sediment exchange landward of primary dunes. Backdunes are comprised of a mix of shrubby and herbaceous species including false rosemary (Conradina canescens), woody goldenrod (Chrysoma pausciflosculosa), Florida rosemary (Ceratiola ericoides), sandhill milkweed (Asclepias humistrata), and coastalplain honeycombhead (Balduina angustifolia).
Xeric sandy soils comprise gently undulating grasslands within coastal dune fields that are distinguished by dominance of gulf bluestem (Schizachyrium maritimum).
Xeric sandy soils and closed canopies of stunted sand pine (Pinus clausa) and scrub oaks including sand live oak (Quercus geminata), myrtle oak (Quercus myrtifolia) and Chapman’s oak (Quercus chapmanii) make up the coastal scrub. Other characteristics include a midstory of beach rosemary (Ceratiola ericoides) and false rosemary (Conradina canescens), and a groundcover of bare sand and lichens within gaps of shrubs.
Wet sandy soils of variable hydroperiods are located on the low points within coastal dune fields. Interdunal swales are made up of a diverse herbaceous groundcover of variable composition with minimal to moderate wetland shrubs. Species include hay cordgrass, (Spartina patens) umbrella-sedge (Fuirena scirpoidea), Flatsedge (Cyperus), yellow-eyed grass (Xyris) red-root (Lachnanthes caroliniana), and rushes (Juncus).
Hydric mucky soils, often flooded, bridge the land/salt water divide. Distinct zones exist (from Gulf inland) of salt marsh cordgrass (Spartina alterniflora), black needlerush (Juncus roemerianus), and sawgrass (Cladium jamaicense).