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Florida Tour Spotlights Invasive Plants in the Everglades

– Collaborative efforts are underway to preserve and restore natural ecosystems

During a recent fact-finding tour of aquatic ecosystems in southern Florida, officials from the U.S. Environmental Protection Agency (EPA) got an up-close look at how integrated weed management techniques are helping to control invasive weeds in lakes and wetlands.

The three-day site visit was organized by scientists, engineers and educators from a variety of public and private organizations, including the Weed Science Society of America (WSSA), the Aquatic Plant Management Society, the U.S. Army Corps of Engineers and the University of Florida. Participants traveled from the Kissimmee Chain of Lakes near Orlando to the Everglades – a region where more than 10 million people live and work.

“We saw first-hand how invasive plants are threatening native vegetation, fish and wildlife habitats, and the water supplies used for drinking, irrigation and recreation,” said Lee Van Wychen, science policy director for the Weed Science Society of America. “But we also saw real-world examples of how integrated management strategies are turning the tide – helping to restore and preserve the delicate balance within these complex aquatic ecosystems.”

Here are a few of the many key findings from the tour:

  • Invasive plants are a significant threat to the Everglades. In touring the Loxahatchee National Wildlife Refuge, Everglades National Park, canals and storm-water treatment areas, participants saw a proliferation of invasive plants that are degrading the region’s ecosystems and water supply. They observed invasive melaleuca trees (Melaleuca quinquenervia), infestations of Old World climbing fern (Lygodium microphyllum) that are killing the tree islands, and canals clogged by water hyacinth (Eichhornia crassipes) and water lettuce (Pistia stratiotes).
  • Hydrilla is invading the region’s lakes and canals. Hydrilla (Hydrilla verticillata) is a submersed invasive plant that significantly alters the temperature, pH and dissolved oxygen in water – destroying fish and wildlife habitats and driving out native plants. In Florida’s Lake Tohopekaliga, participants observed areas where hydrilla has been controlled with a contact herbicide. The native plant American eelgrass (Vallisneria) was once suppressed by hydrilla, but now has begun to thrive in the herbicide-treated zones.
  • State and federal agencies and contractors are collaborating to protect wildlife and water supplies. In planning and implementing management programs, officials say they carefully consider the need to protect threatened and endangered species, critical fish and wildlife habitats, and the water pumps that remove drinking water from lakes. For example, hydrilla management at Lake Tohopekaliga must take into account the presence of the endangered Everglade snail kite hawk (Rostrhamus sociabilis plumbeus).
  • Wading birds depend on the elimination of water hyacinth and the restoration of native plants. At Lake Okeechobee, floating invasive water hyacinth clogs streams, water intakes and conveyances, shades out native plants and greatly impairs river habitats. Careful herbicide applications by trained personnel have provided excellent control of water hyacinth without affecting native plants.
  • High-tech safety measures are used routinely when herbicides are applied in critical Everglades habitats. Officials have adopted GPS technology to map application areas, and specially designed nozzle tips are used for precision application and minimal spray drift. Herbicide applicators are well-trained and keep extensive records of each treatment so that results can be evaluated and used to improve future management plans.

“It is clear that integrated weed management using a variety of control techniques is instrumental in preserving fragile aquatic ecosystems and in protecting both drinking water and natural habitats for future generations,” Van Wychen said. “The EPA has played an essential role in this success story by administering the herbicide registration process for more than six decades and determining how, where and when products can be safely and effectively applied.”

To review a full report of the Florida tour, visit http://www.wssa.net.


About the Weed Science Society of America:
The Weed Science Society of America, a nonprofit professional society, was founded in 1956 to encourage and promote the development of knowledge concerning weeds and their impact on the environment. The Weed Science Society of America promotes research, education and extension outreach activities related to weeds, provides science-based information to the public and policy makers, and fosters awareness of weeds and their impacts on managed and natural ecosystems. For more information, visit http://www.wssa.net.