Weeds can turn an enjoyable fishing or boating pond into an unsightly body of water choked with vegetation that snags fish-hooks and paddles. Like weeds on land, pond weeds need sunlight to grow. Once you get rid of them, prevent them from returning by digging the pond to at least 5 to 6 feet deep, if possible, so sunlight can't reach the bottom. Discourage weeds that grow around the shoreline by increasing the slope of the edges to minimize shallow water.
Things You'll Need
- Scythe, hedge trimmers or string trimmer
- Grass carp
Pull or cut weeds by hand around the shoreline. If the infestation is small, use a scythe, hedge trimmers or a string trimmer. "This can be effective against emergent weeds such as cattails and some submerged weeds and should start in spring when leaves first begin to appear," according to the Ohio State University Extension Bulletin, "Ohio Pond Management." "By repeatedly removing the leaves on cattail plants, the food supply in the underground tuber will be depleted and the plant will eventually die."
Examine the appearance and growth habits of the weeds to identify them in the event you need to get rid of them by other methods. This may be necessary if there are too many weeds to cut or pull. Use an online site for identifying aquatic weeds or take a sample in a plastic bag to your county Extension agent so she can tell you what they are.
Apply chemical weed control appropriate for the kind of weeds you have and the use of your pond, if you have too many weeds to pull by hand. Consult with your county Extension agent or agricultural dealer to find the most effective chemical that won't interfere with other uses of the pond, such as watering livestock, fishing, swimming or irrigation and apply it according to label directions.
Stock the pond with sterile grass carp, a species of fish which eats pond weeds, for ongoing control. Formally known as triploid white amurs, grass carp follow moving water, so install a barrier if a stream flows into or out of your pond. Find a grass carp dealer in your area by contacting your state Department of Natural Resources or county Extension agent.
Tips & Warnings
- For ongoing control, "a healthy pond should have an algae bloom thick enough to where you can only see about 18 inches into the pond," according to "Controlling Weeds in Your Fish Pond," published by North Carolina State University Cooperative Extension. The algae blocks sunlight, smothering weeds that begin to grow at the bottom of the pond. Fertilizing the pond in summer encourages algae growth.
- Photo Credit pond image by Sandra Henderson from Fotolia.com