Herbicides are designed to kill plants. At certain concentrations, herbicides remove all kinds of plants, making them a popular tool to control weeds and invasive plants. But this is risky if the goal is to protect native plant communities. Wetlands such as marshes and swamps are productive ecosystems that crucially contribute to cycling nutrients, regulating our climate, and sustaining wildlife. Aquatic plants living in wetlands remove pollutants from surface water and provide habitat for insects, fish, amphibians, and birds (Figure 1). The more diverse the aquatic plant community, the greater the variety of services it may be able to provid...