Invasive Exotic Plants
Most of the 25,000 or so species of plants that have been brought into Florida are relatively harmless. We depend on some of these species for our sustenance and economy.
Crudely 2000 of the species that have been brought in escape at least occasionally and may naturalize. Many of these are occasional or rare escapes from agriculture and landscaping. Others, often accidentally introduced pan-global weeds, occupy niches to which our native species are not well adapted - such as disturbed roadsides and old fields. Only a relative few escape into native ecosystems, and most of those simply take up a small part of the ecological space that would otherwise be filled by native species.
However, a few introduced species have proven to be highly invasive. They not only escape into native ecosystems, they aggressively displace the native plant species. By doing so, they often also displace native animals. These relatively few species pose a real danger to Florida's native ecosystems and sometimes, a real danger to our economy.
Exotic animals also pose a problem. Species such as the European wild boar, starling, and parakeets roam wild in Florida. Some, such as the European wild boar, which uproots and eats acres of understory plants, are highly destructive to natural environments. Non-native insects and disease organisms can threaten both our native flora and our agricultural economy.
Preservation of Florida's native flora depends in part on recognizing and controlling species with known aggressive qualities as well as preventing new invasive species from becoming established.
What's wrong with invasive plants?
According to the Florida Exotic Pest Plant Council (EPPC) invasive exotic pest plants are biological pollutants. Menacing exotics may be responsible for destroying more natural habitat each year than is destroyed through land development.Highly invasive exotic species severely disrupt native ecosystems. They may totally displace native species. Examples are melaleuca, air potato, Chinese privet, coral vine, wedelia, and kudzu.
They may eliminate or severely alter habitat for wildlife by displacing food plants or altering the structure of the ecosystem.
A few problem exotic species are extremely flammable and may pose a danger to humans, as well as wildlife and the native flora, when they burn. Example species are the old world and Japanese climbing ferns and melaleuca.
Some invasive species can invade and clog waterways. Mechanical and chemical control of water hyacinth, water lettuce, Hydrilla, and other exotic aquatics can be extremely expensive.
Aggressive species often are ignored until there is a problem of such great magnitude that control becomes difficult, impractical, or extraordinarily expensive.
They are typically difficult to eradicate. Hand clearing, broad-scale use of herbicide, bio-control, fire, flooding, and clearing followed by herbicide use are just some of the means used to control problem plants. The cost is often funded by our taxes.
Where do these plants come from?
Exotic plants can and have been introduced accidentally and intentionally, by private enterprises as well as by the government.
Accidental imports have arrived as contaminants in bales and cartons of valid agricultural and freight shipments. Some arrived in the ballast water of old sailing ships.
Some deliberate imports came in as ornamentals (coral vine, lantana, water hyacinth), some for erosion control (kudzu), some for the aquarium trade (Hydrilla, Brazilian elodia). Some came in with government approval. Some were smuggled in. Some came in before we had import regulations or recognized invasive species as problems.
What can one person do?
- Become informed, and share your knowledge.
- Learn how to tell the invasive exotics from less dangerous species.
- Remove invasive exotics from your own yard or land.
- Don't use nearby natural areas as places to throw yard debris.
- Volunteer to remove exotics from natural areas.
- Support bio-control programs.
- Let your elected representatives know that you support the control of exotic species.
