In this context, the phrase "chemical control" refers to the use of specially formulated pesticides to kill or control plants. The United States Environmental Protection Agency (EPA) defines a pesticide as “a substance or mixture of substances intended for the prevention, destruction, repulsion, or mitigation of any pest,” including weeds. The term pesticide sometimes causes confusion as it covers a broad range of substances including herbicides (which target plants), insecticides (which target insects), fungicides (which target fungus) and others. Under United States Law, a pesticide is also a substance intended for use as a plant growth regulator, defoliant or desiccant.
Managing invasive plants very often requires the use of herbicides. A herbicide is a type of pesticide which has been specifically formulated to control weeds. In Florida, invasive aquatic plants such as hydrilla, water hyacinth, water lettuce, and torpedo grass are managed with herbicides specifically registered and approved for use in aquatic environments.
Environmental managers, including aquatic weed managers, have learned much from the past, and are determined to conduct their work in appropriate ways using compounds that are registered for use and regulated by the EPA as well as by state agriculture and environmental authorities. In addition, pesticide applicators are certified by the Florida Department of Agriculture and Consumer Services and must maintain their certification by regularly earning Continuing Education Units (CEUs).
Continuing research by chemists, agronomists and other scientists, as well as the technical education and training of personnel, make invasive plant management using herbicides a science as well as an art. Agency employees, field personnel and citizens should all be vigilant against pesticide misuse whether by agencies, companies or individuals.