The key to controlling aquatic vegetation is proper identification. Guessing can be expensive when you don't know what you are trying to control. Fresh samples may be submitted to your local county Extension agent or fisheries biologist for identification and control recommendations. For pond owners with Internet access, the Extension Service has a website called 'Aquaplant' that provides photos, sketches, descriptions and control options for over 50 common weed species. In addition, labels for various herbicides can be downloaded to aid the pond owner in determining the best course of action.
Chemical control involves using one or more approved herbicides to control targeted species.
Pond owners should closely follow label directions, as with the use of any pesticide. Severely infested ponds should be treated in sections with a week resting period between treatments. Too much decaying vegetation over too short of a time may result in oxygen depletion . The risk of oxygen depletion becomes greater during the hot days of summer. Biological control usually refers to triploid grass carp.