Some lakes draw down the water level in the winter to freeze the roots. This is very hard on the fish that move into the small areas of the deep holes. The smaller fish have nowhere to hide from the larger fish and are eaten. In Lincoln Pond the milfoil infestation became much worse after a draw down as this was the most aggressive plant to return. It took over the whole lake bottom where the sediments had been exposed.
Biological control seems to be a bright light on the horizon.
Introduced grass carp may control weeds in lakes, but they eat native plants before they eat milfoil, and too many could destroy all desirable native plants. Some lakes have experienced a muddy bottom and algae in the water column after carp introduction. The weevil, Euhrychiopsis lecontei , has been touted by Middlebury College as a potential control organism. It is an attractive alternative because it is a native weevil that attacks milfoil. Unfortunately, the weevil's life cycle appears to allow the milfoil to come to the surface through July where it continues to impact recreational uses.