2012 FDOT Mitigation Plan - Southwest Florida Water Management ...

species include cabbage palm, salt-bush (Baccharis halmifolia), wax myrtle (Myrica cerifera), and saw palmetto
(Serenova repens). Ground cover varies depending on the shade coverage, but includes sawgrass (Caladium
jamaicense), broomsedge (Andropogon glomeratus), swamp fern (Blechnum serrulatum), fleabane (Pluchea
odorata), and various sedges. Where the canopy has slightly opened, there are also a few pockets of sawgrass,
black needle rush (Juncus roemerianus), and cordgrass (Spartina patens) within the hammock.
The boundary between the fallow field and the hammock has two large parallel, shear-sided perimeter ditches
with upper slopes and adjacent spoil ridges covered with dense Brazilian pepper. Within the lower sideslopes of
these steep and deep ditches, there is coverage of mangrove species (Aviennia germinans, Rhizophora mangle,
Laguncularia racemosa). These deep ditches connect with the mosquito ditches and swales dredged through the
salt-marsh and mangroves, allowing saltwater intrusion to move further inland than historic conditions. Kept in
place, the deep ditches and spoil ridges substantially hinder wildlife movement from the hammock to the created
marsh habitats. Enhancement objectives include backfilling the two perimeter ditches to create the oligohaline
marsh transition to the hammock. In addition, the B. pepper will be eradicated and controlled via herbicide within
the hammock.
Mangrove & Salt-Marsh (49 acres)
Mangrove swamp (35 acres) forms an inter-related mosaic with the salt-marsh habitat (14 acres). The mangrove
habitat includes red, black and white mangrove species. The marsh habitat has saltwort (Batis maritima),
glasswort (Salicornia bigelovii) and salt grass (Distichlis spicata). Habitat improvements will include herbicide
eradication of exotic & nuisance species, which is primarily B. pepper located on the spoil mounds. Since the
mosquito ditches could not be graded without the potential alteration of drainage conditions west of the tract at the
Bahia Beach Marina complex, no earthwork activities will be conducted in these habitats.
Temperate Hardwoods (9 acres)
The temperate hardwood area is within the northeast corner of the tract. The minor canopy coverage is comprised
of cabbage palm, slash pine, and laurel oak. Groundcover includes saw palmetto, sawgrass, and swamp fern.
Exotic species coverage include B. pepper, lead tree (Leucaena leucocephala) and cogon grass (Imperata
cyclindrica). Improvements to this transitional wetland habitat will include the herbicide eradication and
maintenance to control exotic and nuisance species.
Attachment B – Schedule
The schedule has included contracting with a consulting firm (Atkins North America, formerly PBS&J) to obtain
additional site information and prepare the design plan (Figures C, D). Final design, permitting and contractor
selection is scheduled through 2011, construction and planting during 2012; followed by minimum five years of
extensive herbicide maintenance & semi-annual monitoring activities. Periodic maintenance and annual
monitoring will be conducted after achieving success to ensure the desired habitat conditions will be present.
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