There are many ecological and economic problems associated with invasive plants. An overgrowth of an invasive plant can block the sun from native species, causing them to die and reducing plant biodiversity. The corresponding increase in dead plant material at the bottom of a lake or pond can result in the loss of all oxygen in the water as bacteria break down the dead plants. This process is called eutrophication. Invasive plant species can also crowd and degrade bottom habitat for fish and invertebrates.
Many invasive plants, like Hydrilla (Hydrilla verticillata), can form large mats. These mats often jam propellers and ruin boat engines. The mat may grow so thick that the water becomes inaccessible to boaters and swimmers. Plants can also foul anglers’ equipment. Some aquatic invasive plants are vectors for diseases that impact native wildlife.