|
|
Florida's Nature - 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.
Types of Pine Flatwoods are Wet ( Hydric ), Moist & Dry ( Scrub ). This is
determined primarily by elevation, the depth of the sand over the hardpan or
limestone substrate. Areas with deeper sand deposits are higher and also dryer,
resulting in a Scrub type habitat while low lying areas are where wet or hydric
conditions occur.
Saw
palmetto, Wiregrass, Fetterbush, Tarflower, Gallberry, Blueberry, Broomsedge, Wax myrtle and St.
Johnswort are some of the common understory plants of the Pine flatwoods.
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 level was higher than that of present day several sand
ridges formed of 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 sand ridges of
current day Florida Scrub. Because of this, some of the plants found
there at present are found nowhere else.
Since development has taken or fragmented much of the original
existing scrub habitat much of the plant & animal endemic to it, as
well as the ecosystem itself are endangered, threatened or rare.
The two largest areas of remaining scrub are found on The Atlantic Costal
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. 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 - Coastal Strand plants - Sea Grape, Sea Oats, Coastal Sea
Rocket, Railroad Vine, Bitter Panicgrass
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.
|
Mangrove Ecology,
Silviculture and Conservation
By Peter Saenger |
