Wetlands
In Florida, wetlands are defined as areas that are inundated
or have saturated soils for long enough periods of time to
support plants which have adapted to and can grow and reproduce in
flooded conditions or saturated, anaerobic
soils.
Wetlands can form in low lying areas such as depressions or sloughs,
where there
is an underlying strata of
"hardpan" consisting of a mixture of sand and clay or limestone
which slows drainage or where the groundwater level is at
or above the surface of the landscape.
The length of time that these wetland habitat remain flooded is
referred to as the hydroperiod. Hydroperiods vary in length and may
be as brief as a couple of weeks or as long as a year or more. Some
wetlands never dry out completely while others dry out only every couple
years or during periods of extended drought.
For a complete technical description of the rules for identifying
and delineating wetlands as set forth by the Florida Department
of Environmental Protection,
click here. (P.D.F.
format)
Originally covering about 60 percent of Florida's
landmass, remaining wetlands have been reduced to less than
half of the original amount. Capable of storing huge volumes of
fresh water, marshes slowly filter & release it, replenishing
groundwater and aquifers that provide water for human needs.
Healthy wetlands support an amazing array of birds, crustaceans,
amphibians, reptiles & fish, as well as a wide range of plant
life.
Florida's aquatic
freshwater and marine life, including many commercial and sport
fishes depend on these marshes and swamps for feeding grounds,
nurseries for their young and/or breeding areas.
Florida's wetlands also provide outstanding recreational opportunities for boating, fishing, photography and bird
watching, in fact a major portion of the states annual tourism
income including all available flights to Florida,
is directly & indirectly dependant on these resources.
Freshwater Marsh
A Freshwater marsh may be flooded seasonally or year-round. Marshes
are natures water filters, collecting water and slowly filtering it
through vegetation. This allows suspended particles to settle out,
while plants absorb excess nutrients.
Types of freshwater marshes include Wet Prairies, Depression and
Basin marshes, Floodplain marshes & Bogs.
Common plants include emergent & floating leafed species
such as Cattails, Sawgrass, Pickerelweed, Rushes, Sedges, American
Lotus, American White Water lily.
Click an image to open a larger version
Pictures - (L) Seasonally flooded shallow marsh within a wet
prairie,
(R) Freshwater marsh in foreground with Water lilies,
bordered by Pickerel weed & Sawgrass marsh with Wet Pine flatwoods in
background.
Wet Prairie
Wet Prairie is a seasonally flooded, shallow freshwater marsh found in depressions, sloughs,
finger glades & on the floodplains or margins of lakes, streams and rivers.
Some of the plants common to Wet Prairies include St. John's Wort, Sedges, Muhly grass,
Sawgrass, Groundsel bush, Wax Myrtle, Sundew, Meadowbeauty, Marshpinks,
& Coreopsis spp.
Wet Prairie
Left - Dry season Center - Wet season
Right - Wet Prairie in a woodland depression.
Cypress Swamp, Cypress Strand &
Cypress Dome
Found on the floodplains of freshwater rivers, lakes and seasonally flooded
woodland depressions/sloughs. Dominated by Bald Cypress or Pond Cypress
sometimes with a mix of other hardwood trees. The length of time that Cypress
stays flooded determines what understory plants are present. There may be
aquatic, emergent and
herbaceous plant species present. A Cypress Dome is named for it's shape with
the older, taller trees in the center and smaller, younger trees on the
perimeter. Strands usually follow a slough
resulting in the strand shape, which is longer than it is wide. The margins of Cypress strands
& domes usually support a higher number of plant species than the interior &
often transition into a Wet Prairie or Wet Flatwoods habitat.
Pictures - (L) Cypress Dome, (C) Interior of a Cypress dome during the dry
season,
(R) Cypress Swamp on the floodplain of a freshwater river.
Mangrove Forests & Swamps
Found worldwide from approximately 25 to 28 degrees north and south latitudes,
Mangroves are comprised of 70 or so species which have adapted to life on the
protected shorelines of marine estuaries and bays.
Red,
Black, and White Mangroves are the three species of Mangrove that grow in
Florida. Plants associated with Mangroves include Buttonwood, Saltwort, Glasswort, Christmas berry, Sea-blite &
Saltmarsh cordgrass.
In Florida, mangroves grow south of the frost line with the highest
concentrations of trees found further south. The Ten-thousand Islands on the
S.W. Florida coast is made up of hundreds of Mangrove islets and is a popular
destination for fishermen and birdwatchers alike.
Mangroves are a critical habitat and feeding ground for over 120 animal species.
The Peregrine Falcon, Bald
Eagle, Osprey, Pelican and several varieties of Herons use mangroves for
hunting, nesting or roosting.
Blue claw, Fiddler and Mangrove crabs, shrimps, corals, sponges, oysters,
seahorses and a host of other marine invertebrates also call the mangroves home.
Pictures - (L) Red Mangroves line the Loxahatchee river in South Florida,
(C) Mangroves at low tide, showing stilt roots. (R) This picture shows the dense
tangle of Red Mangrove stilt roots that provide shelter for numerous marine
animals, help to dissipate wave energy and stabilize shorelines in Florida.
Hardwood Swamps
Hardwood swamps consist of various hardwood trees or a mixture of hardwoods and Cypress.
This type of habitat occurs on floodplains &
upland areas that are lower than the surrounding area. Water
hickory, Cypress, Holly, Maples, Oaks, Cabbage
palms and Bay trees, usually with a dense understory of vines, ferns and herbaceous plants.
Pictures - (L) Interior of a hydric hardwood swamp with lush understory growth
(R) During the dry season a small blackwater stream trickles through a mix of
Cabbage palms, Oaks and Maples.
Baygall, Bay Swamp
Perpetually wet areas that receive slow seepage or drainage from
higher elevations, soil is that of a heavy acidic muck and peat with a thick layer of leaf litter. Dominated by Bay
trees, hence the name. Loblolly Bay, Swamp Bay, Red bay, Sweet Bay. Understory plants
include Dahoon holly, Wax myrtle, Fetterbush,
Royal fern, and Cinnamon fern.
Picture - A trail winds through a young Baygall or Bay swamp
Salt Marsh
Found in the sheltered tidal zones of rivers, creeks and bays. In the southern
part of Florida salt marshes are broken up or replaced by Mangrove
swamps & forests.
The degree of water salinity determines
the dominate plant. Smooth cordgrass in the normal tidal zone and black
needlerush in areas that receive less frequent inundation of brackish water,
such as during occasional extreme high tides and storms. Salt marsh habitat
offer juvenile fish a protected nursery, away from larger fish who would prey on
them. They filter pollutants and trap sediments from storm waters that would
choke offshore reefs and the vegetation also helps prevent erosion.
Upland Habitats
Pine Flatwoods
Pine Flatwoods are the most widespread eco-systems in Florida, occupying as much
as 50% of Florida's land area. As the name states, the topography of a Flatwoods
is relatively uniform, the soil is generally sandy, poorly drained & acidic with
little organic content with a underlying layer of hardpan. This layer of hardpan
also inhibits drainage in the wet season causing Flatwoods to be flooded for
part of the year, experiencing alternating periods of flood and drought. The
canopy is open, allowing plenty of sunlight to reach the understory plants.
The understory of a healthy Pine Flatwoods is regulated by regular fire, areas
that burn more often have an understory dominated by grasses and diverse
herbaceous plants, while those that experience less frequent fires have more
leaf litter/debris with an understory dominated by shrubs. If fire is absent for
long periods Pines will eventually be succeeded by Oaks and the subsequent
development of of a closed canopy forest or Hammock which inhibits understory
growth.
Saw
palmetto, Wiregrass, Fetterbush, Tarflower, Gallberry, Blueberry, Broomsedge, Wax myrtle and St.
Johnswort are a few of the plants common to Pine flatwoods habitats.
Pictures - Two examples of Pine Flatwoods
Dry Prairie
Large areas of native grass or shrublands on dry, flat terrain which are subject
to frequent fires, with trees occupying less than 15 percent of the area.
Although classified as a Dry Prairie, the sandy, acidic soils often have a
hardpan substrate which impedes drainage resulting in flooding during the rainy
season. Grasses, sedges, herbs, and shrubs. Saw palmetto,
Fetterbush, Tarflower, Gallberry, Wiregrass, Carpet grass.
Pictures - (L) A lone Whitetail deer grazes on a Palmetto Prairie. (R) Grasses dominate
this Dry Prairie scene.
Florida Scrub Habitats
When sea levels were much higher than that of present day, sand
ridges formed from deposited sediment washed to the sea from eroding
mountains to the north. As the sea level receded these deposits
became islands.
Plants colonized these islands, later as sea levels dropped further the Florida
peninsula emerged the islands became the current day Florida Scrub.
Since development has overtaken or fragmented much of the original scrub habitat,
many of the plants & animals endemic to it are considered endangered, threatened or rare.
The two largest areas of remaining scrub are found on The Atlantic Coastal
Ridge, which runs parallel and in close proximity to the east coast
of Florida from northern St. Lucie county south to Miami-Dade and
Monroe counties, ranges in height from 10 feet to
well over 50 feet above sea level & the Lake Wales Ridge which extends from Lake and Orange counties
in the north, south through Highlands county and ranges in height
from 70 feet to over 300 feet above sea level at its highest point.
Some of the plants associated with Florida scrub include Chapmans oak, Sand Pine,
Myrtle Oak, Scrub Oak, Scrub Holly, Florida Rosemary, Lichens & Mints.
Pictures - (L)
Sand Pine & Oak scrub, (C) Sand Pine Scrub (L) Sand Pine & Rosemary Scrub
Oak Scrub
Found on deep, white sands where fire or clear cutting
has removed the pine overstory. Common plants include Myrtle Oak, Chapman's Oak, Dwarf
Live Oak, Scrub
Holly, Hog Plum, Scrub Hickory, Florida Rosemary, Gopher Apple and Saw
Palmetto. Areas of open white sand are common in this type of
habitat.
Pictures - (L) This Oak scrub was once Sand Pine scrub, the overstory of Sand
Pine has been removed by a catastrophic fire. (R) Lichen are common on the dry,
sandy soil of the Oak scrub.
Coastal Strand & Beach Dunes
Sandy, well drained soils along the coastline. From the open sands of the upper beach and the dune
lines - inland to where more highly developed plant communities are found.
Beach morning glory, Railroad vine, Sea
Oats, Saw Palmetto, Spanish Bayonet, Prickly Pear cactus, Sea grape,
Cocoplum, Grey Nicker
Pictures - Dune & Coastal Strand plants withstand a harsh environment. Sea Grape, Sea Oats, Coastal Sea
Rocket, Railroad Vine, Bitter Panicgrass are some of the more common ones. They
help stabilize the shifting sands and reduce erosion from wind and waves.
Hammocks
Hammocks are located from the coastal strand inland to wetlands, prairies and
flatwoods and vary from Mesic (moist) to Xeric (dry) habitats. Trees associated
with hammocks include Live oak, Laurel oak, Sabal or Cabbage palm.
Broadleaf evergreen and
semi-deciduous species include Red maple,
Mahogany, Gumbo limbo, Cocoplum, Florida elm, Holly, Marlberry,
Mulberry and Southern Magnolia.
Hardwood hammocks provide habitat for a variety of epiphytic plants
or
"air plants", including native orchids and Spanish moss. Attached to
the bark of a host tree and acquiring nutrients from rain
water, the air and pockets of moisture in the bark of the host tree. Common on
Oaks, Sabal palms and Cypress trees, these plants are not parasitic and usually
do not harm the host tree.
Pictures -
(L) Inland Oak hammock, (R) Coastal or Maritime Oak hammock
Palm Hammock
In South Florida - on the Coastal strand, Flatwoods, Bottomland forests,
Prairies, margins of marshes and other wetlands. As the name implies the
dominate species is the Sabal palm. Understory plants include vines, grasses,
ferns and various herbaceous plants, which are determined primarily by
the type of soil and available moisture.
Pictures - Two views of Palm hammocks
Sandhill
Areas of rolling terrain on deep,
well-drained, white to yellow, sterile sands. A xeric plant
community that depends on fire to maintain it's ecology. Longleaf pine, Turkey oak and
Bluejack oak, Wiregrass,
Partridge pea, Beggars tick, Milk pea, Queen's delight, herbaceous plants and grasses.
Tropical Hardwood Hammocks
South Florida in areas along coastal uplands, in
the Florida Keys and tree islands within the Everglades where frost
is a rare occurrence.
This habitat is home for over 100 varieties of trees
and shrubs and marks the northern most range of many tropical
plants, including many rare and
endangered species.
Soils types include shell, sand and limestone.
Today, due to development of coastal areas this habitat is found only as scattered remnants in nature preserves.
Strangler fig, Gumbo-Limbo, Live-Oak, Mastic, Bustic, Lancewood,
Ironwood, Poisonwood,
Pigeon plum, Jamaica dogwood, Bahama lysiloma, Mahogany, Thatch palms and
Manchineel.
Pine Rocklands
Found on the southern most tip of
Florida and home to the endangered Dade county pine, Pinus elliottii var. densa .
This habitat is based on a limestone substrate covered with a thin layer of
sand. Found only on the Miami
Ridge, Florida Keys, Big Cypress Swamp, the Bahamas
and Cuba.
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