Historic vegetation was dominated by open woodlands of longleaf pine with an understory of wiregrass. Other natural communities include to pine savannas, flatwoods, and xeric hardwood forests.
Upland longleaf pine woodland
These are woodlands dominated by longleaf pine and subject to frequent fires. The Atlantic coastal plain upland longleaf pine woodlands occur on uplands and on the higher parts of upland-wetland mosaics, while the east Gulf coastal plain interior upland longleaf pine woodlands occur on rolling dissected uplands, inland of the coastal flatlands. Soils are well- to excessively drained. Scrub oaks such as turkey oak and bluejack oak are often in the understory. The herbaceous layer is dominated by grasses, particularly wiregrass: in the north and in the south.
s consist of stands of longleaf pine on very well-drained, sandy hills of the coastal plains of Florida. These stands are maintained by frequent fires. Turkey oak is common in the understory. Wiregrass makes up the ground layer.
Near-coast pine flatwood
are forests and woodlands on broad, sandy flatlands along the northern Gulf of Mexico. Trees are typically longleaf pine or slash pine. Fires are naturally frequent, occurring every one to four years. Understory vegetation ranges from open and grassy to dense and shrubby, depending on fire history. Shrubs include swamp titi, gallberry, Appalachia tea, fetterbush lyonia, and saw palmetto.
Nonriverine cypress dome
s are small forested wetlands characterized by their dome-shaped appearance, with taller trees in the center and shorter trees around the perimeter. These wetlands occur on poorly drained depressions surrounded by pine flatwoods. Pond cypress dominates the canopy, which it shares with swamp tupelo and sweetgum.
Oak dome and hammock
The southern coastal plain oak dome and hammock occurs as thick stands of evergreen oaks in small patches on shallow depressions or slight hills. These forests are distinct from their surrounding habitats, which are often longleaf pine-dominated. On mesic sites, common species are southern live oak, sand laurel oak, and American persimmon. The understory is sparse, with trumpet creeper and greenbrier. On xeric sites, common species are sand live oak, longleaf pine, southern live oak, wiregrass, and southern dawnflower.
Hydric hammock
s are found on the flat lowlands of the southern and outermost parts of the coastal plain, usually over limestone substrates. These forests of evergreen and deciduous hardwood trees occur near the floodplains of spring-fed rivers with relatively constant flows. They can be large areas of broad, shallow wetlands. Common trees include Atlantic white cedar, elm, sweetbay magnolia, swamp laurel oak, southern live oak, and cabbage palm. Dahoon holly is a typical shrub.
Maritime forest
On the Gulf coastal plain, maritime forest consists of a mosaic of forests and shrublands on barrier islands and strands. It occurs in sheltered areas behind coastal dunes and grasslands. Forests are dominated by a mixture of needle-leaved and broad-leaved evergreen trees, including sand pine, slash pine, longleaf pine, southern live oak, cabbage palm, pignut hickory, and sand hickory. Wetland areas are dominated by pond cypress and sweetbay magnolia. Wind and salt spray from the ocean can make these forests appear pruned and sculpted. On the Atlantic coastal plain, maritime forest consists of forests and shrublands on stabilized upland dunes of barrier islands and strands. Oaks tend to dominate the overstory, often southern live oak and sand live oak. Woodlands dominated by pine species include southern species such as longleaf pine, pond pine, and slash pine. The understory is dense and shrubby, including southern live oak, sand live oak, laurel oak, Chapman oak, myrtle oak, and southern magnolia.
Dry upland hardwood forest
This includes a variety of deciduous oak forests and mixed evergreen forests dominated by oak. Pines are often present as well. This forest is found in fire-sheltered locations surrounded by pine-dominated uplands, including slopes near rivers and sinkholes. Sand laurel oak is the typical oak species; post oak, southern red oak, and white oak are associates. The forest canopy can be diverse, including hickories and other hardwood species. Common pines include loblolly pine, spruce pine, or shortleaf pine. To the south, this becomes the southern coastal plain oak dome and hammock.
Mesic slope forest
On the southern Atlantic coastal plain, mesic slope forest is found on steep slopes, bluffs, and sheltered ravines. Fire is rare. They occur on mesic soils, and contain species not found in other forest systems in the area. These include American beech, southern magnolia, and purple anise. The related east Gulf coastal plain northern mesic hardwood slope forest occurs to the north and has more deciduous trees. On the inland east Gulf coastal plain, mesic slope forest consists of deciduous hardwood forests found in slopes and ravines. They inhabit mesic sites between drier uplands and moister streams. American beech, white oak, and cherrybark oak are the distinguishing tree species. Loblolly pine is common in the southern part of the range. The related southern coastal plain mesic slope forest is found to the south.
Dry and dry-mesic oak forest
These forests occur on dry and dry-mesic sites and are dominated by oaks and hickories. These habitats are protected from fires by either steep topography, isolation, or limited flammability of the vegetation. Typical canopy species include white oak, sand laurel oak, mockernut hickory, and pignut hickory.
Highlands freshwater marsh
es are highland marshes found in shallow peat-filled valleys, the basins of dried lakes, and the borders of existing lakes. The vegetation mosaic includes a range of mostly herbaceous plant communities, varying based on water depth. Deep water supports various submerged and floating plants. Meter-deep water supports emergent herbaceous perennials, typically in dense, monospecific stands; species include bulrush, pickerelweed, and American lotus. Shallow areas only submerged during wet season support more graminoid vegetation, including maidencane and southern cutgrass. Subsidence and drainage pattern changes make these habitats shift and change over time. Soils can be mucky, loamy, or sandy, but they are generally above permeable subsoils that create standing water much of the year. These marshes may also be called meadows or prairies.
Nonriverine basin swamp
s occur in large, seasonally-flooded depressions away from rivers. Sites are often forested by trees including bald cypress, swamp tupelo, evergreen shrubs, and hardwoods. Slash pine is sometimes found. Characteristic shrubs include buckwheat tree, swamp cyrilla, fetterbush lyonia, and laurelleaf greenbrier.
Blackwater river floodplain forest
s occur in the drainages of blackwater rivers and streams. Typical trees include bald cypress, water tupelo, and Atlantic white cedar.
Fauna
Mature longleaf pine forests are important habitat for the vulnerable red-cockaded woodpecker and gopher tortoise.
Areas of natural habitat
Today, nearly all mature stands of longleaf pine are gone, and only a few isolated sites still contain substantial natural habitat. In many areas, longleaf pine forests have been replaced with plantations of slash pine, which are less biologically diverse than native habitat.