How to Control Pondweed
Before you use herbicides, there are a couple of other pondweed control methods that are worth considering. Prevention is the best method of control, so think carefully before you plant. If you decide to plant them, use containers to hold the roots rather than in the mud at the bottom of the pond. In small ponds, try getting rid of pondweeds by removing them manually. In large ponds, releasing grass carp in the pond will keep the plants under control. Grass carp feed on the tender, submerged parts of the plant. If these methods are impractical for your situation or don’t solve the problem, it’s time to consider managing pondweed in ponds using herbicide. Where herbicides for lawns and gardens are usually chosen based on the weed you are trying to kill, herbicides for ponds are tailored to the site. Read the label carefully before you choose, paying special attention to precautions, restrictions, and intended use. Use the least toxic herbicide to protect the fish and other wildlife in your pond and preserve enough plants to support them. Herbicides containing the active ingredient endothall are a good choice for controlling pondweed. Once you’ve chosen your herbicide, follow the label instructions exactly. Measure carefully and if you have to use it more than once, wait the recommended period of time before the second application. Never use an herbicide in a pond that isn’t specifically labeled for aquatic use.