sometimes called American or Canadian water weed or pond weed, is widely known as the generic water weed. The use of these names causes it to be confused with similar-looking plants, like Brazilian elodea (Egeria densa) or Hydrilla (Hydrilla verticillata). American water weed is an attractive aquarium plant and is a good substitute for Brazilian elodea. It can be used for science experiments in classrooms demonstrating how plants use carbon dioxide with the usage of bromothymol blue.
The American water weed lives entirely underwater with the exception of small white flowers which bloom at the surface and are attached to the plant by delicate stalks. It produces winter buds from the stem tips that overwinter on the lake bottom. It also often overwinters as an evergreen plant in mild climates. In the fall, leafy stalks will detach from the parent plant, float away, root, and start new plants. This is the American water weed's most important method of spreading, while seed production plays a relatively minor role.
Herbicide Management Options:
Sonar AS: Is a florid one compound and comes in a liquid formulation, and have been effective on Elodea. This is a broad spectrum, systemic herbicide. Systemic herbicides are absorbed and move within the plant to the site of action. Systemic herbicides tend to act more slowly than contact herbicides.
Reward: is a liquid diquat formulation that has been effective on Elodea. It is a contact herbicide. Contact herbicides act quickly and kill all plants cells that they contact. A non-ionic aquatically registered surfactant (see the label) will have to be added to the Reward solution for good results.
Biological Management Options:
Grass Carp: will control Elodea. Grass carp stocking rates to control Elodea are 20 fish per surface acre of plant biomass. Elodea is a preferred food for Grass Carp. In South Carolina, only Triploid Grass Carp are legal and a permit from the South Carolina Department of Natural Resources is required. AMS is licensed to provide these permits for you.