Elodea (Anacharis)

Elodea is a genus of aquatic plants often called the Water weeds. Elodea is native to North America and it is also widely used as aquarium vegetation. The introduction of some species of Elodea into waterways in parts of Europe, the Australia, Africa, Asia, and New Zealand has created a significant problem, and it is now considered a noxious weed in these areas.

Elodea canadensis, sometimes called American or Canadian waterweed/pondweed or Anacharis (a former scientific name) is widely known as the generic water weed. The use of these names causes it to be confused with similar-looking non-native plants, like Brazilian elodea (Egeria densa) or hydrilla (Hydrilla verticillata). American waterweed is an attractive aquarium plant, and is a good substitute for Brazilian elodea.

The American waterweed 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 waterweed’s most important method of spreading, with seed production playing a relatively minor role.