Florida is known for its invasive species. If you polled a hundred people about which is the worst, you would probably get some predictable answers: Pythons, fire ants, tegus, lionfish.
But what about hydrilla, water hyacinth and water lettuce? While the animals get most of the attention, more money and effort is expended on battling non-native vegetation. Aquatic weeds are a major focus, since if left unchecked they can quickly block access to our state’s waterways and interfere with flood-control structures.
Traditionally, the Florida Fish and Wildlife Conservation Commission — which has a statutory obligation to manage invasive plants in state waters — has fought the weeds with herbicides.
But since the red tide and blue-green algae outbreak of 2017, that’s become controversial. Many people believe that the nutrients released by decaying sprayed vegetation may contribute to these harmful algal blooms.
Additionally, those plants, if left alive, would absorb nutrients from the water — a natural filtration process. Water with fewer nutrients in it cannot support heavy algae growth. However, according to the FWC, that’s not a workable solution unless the plants are native species.
“We have an obligation to manage invasive plants and that currently requires a multi-faceted approach using a variety of tools,” said FWC Executive Director Eric Sutton. “While we all would like to see a future where aquatic plants can be managed without herbicides, we will need innovation and discovery of new techniques to be able to achieve that goal.”
To that end, the FWC has set aside $1 million of current funding to test or implement innovative ideas to manage invasive aquatic plants without the use of herbicides.
“Come one, come all,” said Commissioner Rodney Barreto. “Tell us how we can do better at managing aquatic plants.”
Currently, the FWC employs licensed pesticide and herbicide applicators to spray huge amounts of weed-killing chemicals on many of the state’s fresh waters. How much? Here are a few examples from 2017: 243 gallons of herbicides to treat floating plants and 8,284 gallons to control hydrilla in 4,000 acres of Lake Rousseau; 248 gallons of herbicides to treat floating plants in 3,600 acres of the Withlacoochee River; and 11,307 gallons of herbicides to treat hydrilla in 19,111 acres of Lake Tsala Apopka.
The deadline for submitting ideas to the FWC on how to manage waterbodies without herbicides is Jan. 7. The FWC hopes that the information submitted will form the basis of new pilot projects and future bid proposals.