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Four Invasive Weeds You Don’t Want in Your Pond

Lake and pond owners can all agree on one thing—an invasive plant species is a fast way to ruin your water. Invasives can cause serious consequences for the animal and plant life that depend on your pond and can ruin your enjoyment as well. What are you up against? Here are four species you should watch for in your pond.

1. Starry Stonewort

This invasive plant is actually a type of branched algae that resembles native Chara and Nitella, but is not native to the United States. It is becoming widespread in the Great Lakes region and it produces a dense mat that often crowds out native vegetation. Hand pulling it may be effective for small areas, but make certain to completely remove all parts of the plant, as any fragment can grow and restart the infestation. For larger areas, treatment with copper-based algaecides may be necessary to maintain control.

2. Eurasian Watermilfoil

Like Starry Stonewort, this one isn’t native to the U.S. either. It reached the Midwest in the early 1950s, and it’s been spreading ever since. It can form a dense mats of vegetation at the surface of your pond, which can be a real problem for almost anything you want to do, including fishing. One single segment can take root to form a new colony, it grows rapidly and can take over your entire pond. Hand removal is possible for small areas, but aggressive treatment with an appropriate herbicide may be necessary for advanced invasions.

3. Hydrilla

If you thought the previous plant grew fast, Hydrilla is even worse. It’s been found to grow up to an inch per day, and some stems will grow up to thirty feet long. This aggressive growth is a problem because it’s likely to crowd out nearly all beneficial plants in the pond. Hydrilla is most abundant in the south, but it is certainly on the “watch list” because of its adaptability to many environments.  Small areas can be removed carefully by hand, but herbicides may be needed to combat this invader.

4. Fanwort

This plant is also known as Cabomba, and if you enjoy swimming or boating in your pond, fanwort could create a real problem for you. Any part of this plant can take root, and it can survive even the toughest winters. This plant breaks into fragments very easily, making it difficult to remove effectively by hand. Infestations of this plant may require proper application of herbicide to control.

Wondering what you can do if you find one of these problem plants? If you catch it early, you have options. Small colonies of these plants can be removed with a rake or by hand to carefully clear away the growth and end the problem. In the event the growth is a bit more advanced, you may need to use a combination of methods.  Using herbicide can be an option too, but do your research to make sure you have the right treatment in the right quantity. If you need help, contact us for assistance.