Sweetwater Creek Watershed Mgmt. Plan 2007 Update--Part 2

CHAPTER 8
• Category II are exotic pest plants that have the potential to invade and disrupt native
plant communities as indicated by (1) aggressive weediness; (2) a tendency to disrupt
natural successional processes; (3) a similar geographic origin and ecology as Category
I species (4) a tendency to form large vegetative colonies; and/or (5) sporadic, but
persistent, occurrence in natural communities
• (N) indicates a species listed as noxious on the United States Department of Agriculture
and the Florida Department of Agriculture and Consumer Services lists
• (P) indicates a species listed as prohibited by the Florida Department of Environmental
Protection under Rule 62C-52, F.A.C.
Exotic Plants in the Sweetwater Creek Watershed
The Sweetwater Creek watershed has been susceptible to exotic species invasion as a result of
the physical disruption of habitats for development purposes, agricultural and industrial
operations, and the escape of exotic species from residential landscapes. Information contained
in several reports (see Bibliography) and on site visual inspection of the watershed revealed the
presence of 39 exotic plant species in the watershed; many other species, undocumented as
yet, probably occupy the watershed. Many exotic species are agricultural tree crops and/or
landscape plants that were purposely planted, while others have been introduced accidentally.
Many of the purposely planted exotics remained in the landscape even after land use changes
occurred (e.g., residences built in former citrus grove) and many have been introduced into
landscapes for specimen plants. Of this category of exotic species, the primary species
includes: fruit trees and shrubs (grapefruit, orange, tangerine, loquat, kumquat, Surinam cherry,
banana, papaya, avocado, mango). Other purposely planted species include: asparagus fern,
Australian pine, bamboo, Brazilian pepper, camphor tree, carrotwood, castor bean, chinaberry
tree, Chinese privet, Chinese tallow tree, cogon grass, earpod tree, fig species, Japanese
honeysuckle, lantana, latex plant, lead tree, paper mulberry, punk tree, torpedo grass, water
hyacinth, wild taro. Other species that escaped into the landscape to become well established
include: air potato, alligator weed, hydrilla, Japanese climbing fern, parrot’s feather, skunk vine,
and tropical soda apple. Below is a brief description of a few of the more common exotic
species observed within the Sweetwater Creek watershed. The vegetative descriptions are from
the University of Florida’s Northeast Region Data Center. The photographs are reprinted from
the University of Florida, Institute of Food and Agricultural Sciences Aquatic, Center for Aquatic
and Invasive Plants, online Aquatic, Wetland and Invasive Plant Information Retrieval System
(APIRS).
Alligator Weed
Alligator weed is an immersed plant that thrives in disturbed aquatic
environments, but can grow in a variety of habitats, including dry
land. It may form sprawling mats over the water or along shorelines.
Alligator weed stems are long, branched, and hollow. Leaves are
opposite, simple, elliptic, and have smooth margins. Flowers grow
on stalks and are whitish and papery, and bloom during the warm
months.
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Sweetwater Creek Watershed Management Plan