During the past 400 years, Florida's natural areas have been invaded by mostly tropical and subtropical nonnative plants; and, during the twentieth century, these invasions have increased with the rise of the ornamental plant industry and through unintentional contaminants of imported commodities. Recognizing that research is the basis of environmentally and economically sound invasive plant management programs, the State of Florida, through the Department of Environmental Protection, began funding invasive plant research in 1971. Early research funding targeted biological control methods using insects, herbivorous fish, and plant pathogens, as well as mechanical control and water level fluctuation control methods. In the 1980s, invasive plant management research in Florida shifted toward developing second-generation effective aquatic herbicides such as fluridone and glyphosate that have low toxicities for fish and invertebrates and are relatively selective in controlling invasive aquatic plants among nontarget plant communities. In the 1990s, research priorities targeted wetland and terrestrial species. By 2002, Florida's research program shifted its research priorities and state funding to find new management techniques for hydrilla (Hydrilla verticillata) and for the rapidly spreading Old World climbing fern (Lygodium microphyllum). State, federal, and local agencies have spent more than $250 million since 1980 to control invasive nonnative aquatic, wetland, and upland plants on publicly owned waterways and conservation lands with research funding comprising less than 5% of that total amount.