Eurasian Watermilfoil is an exotic species. Its leaves are feather-like that sometimes produce reddish flowers that extend above the water. Eurasian Watermilfoil's stems are red to brown in color. It can dominate a pond very quickly by fragmentation. Pieces of the plant grow roots to develop a new plant. There are many native milfoil plants that do not have as many feather-like leaves and are much less aggressive.
Pond Dye can be used to limit sunlight into the pond. With reduced sunlight, photosynthesis cannot occur so growth will be stunted.
There are several options to control Eurasian Watermilfoil:
- Use a season long herbicide such as Sonar™ A.S.. One treatment treats Eurasian Watermilfoil and many other common pond weeds for the season.
- Use a broad spectrum contact herbicide, such as Ultra PondWeed Defense®, will quickly kill Eurasian Watermilfoil. Because it does not stay in the water body, multiple treatments may be needed throughout the season.
- Use Clipper™, a fast and selective herbicide that controls tough invasive and nuisance aquatic plants.
Chemical Application Best Practices
Anytime you use chemicals treat weeds and algae, please keep in mind the following:
- Treat your pond in sections. Treat only half the pond's surface at a time. During hot weather or when treating heavy growth, it is important to treat no more than ¼ of your pond at a time and wait the full 14 days before re-applying. This helps lower the risk of fish loss during hot weather or when treating heavy growth.
- Once the weeds have browned & died, use a weed cutter & rake to remove as much dead material as possible. This prevents an accumulation of dead plant material and muck.
- Take a proactive approach to pond management. Use PondClear™, MuckAway™ and Pond Dye to keep your pond looking great. For more information, see our article on the Airmax® Ecosystem™
Ask an Expert
If you are unable to identify your pond weed(s) using our Weed ID Guide, follow this article to email us a photo.