Hydrilla and Eurasion watermilfoil have been the main concern. Unfortunately, this single-use herbicide resulted in fluridone resistant "Hydrilla". He also fought against the spreading of the hydrilla plant in Potomac watershed. In October 2012 there was a hydrilla outbreak. Three exotic, invasive species exist in the lake&colon; water hyacinth, hydrilla and giant salvinia. Several areas of the lake have been infested with hydrilla. Substantial aquatic vegetation grows in the lake, primarily hydrilla. Aquatic vegetation has species of "Chara", "Spirogyra", "Hydrilla", "Potamogeton" and "Vallisneria". "Hydrilla" populations have caused economic, environmental, and ecological damage. Hydrilla also has a harmful impact on bird populations. Hydrilla was first found in the lake in the 1970s. "Hydrilla" is known to have many digestive and health benefits. Hydrilla contains a harmful bacterium that acts as a neurotoxin for some birds. Hydrilla crowds out native species, impedes irrigation, and clogs boat motors. "Hydrilla" has a high resistance to salinity compared to many other freshwater associated aquatic plants.