In recognition of Invasive Species Awareness Week (ISAW) — which wraps up today — the Adirondack Mountain Club (ADK) has this profile about Brazilian elodea (Egeria densa):
Also known as Brazilian Waterweed, Brazilian Elodea is a popular aquarium and water garden plant that is often sold under the generic name “Anacharis.” A submerged invasive perennial plant that looks very similar to some native species, Brazilian elodea is characterized by its bright green coloration and minutely serrated leaves that are 1-3 centimeters long and up to 5 millimeters wide. Brazilian elodea has four (sometimes eight) leaves per whorl; whereas hydrilla, another invasive species, has five leaves per whorl; and the native American elodea waterweed, has only three.
Brazilian elodea also has small white flowers in the spring and fall. The flowers have three petals and either float on the water or above the surface on threadlike stems. Only male flowers have been found in North America so far, so seed production does not occur in its introduced range.
Brazilian Elodea can be found in wetlands, lakes, ponds and slow-flowing streams and can grow in water up to 20 feet deep. It sends stems to the surface where the plant forms dense mats. In North America, Brazilian Elodea regenerates only from fragments that break off to form new plants. This allows the plant to spread quickly.
Volunteer with ADK
Even though ISAW is wrapping up for 2020, there are still plenty of ways to get involved. You can help ADK survey ponds and lakes for aquatic invasive species such as Yellow Floating Heart, European frog-bit, European Water Chestnut, and Curly Leaf Pond Weed. For more information on upcoming workshops and events, go to: Backcountry Water Monitoring Project.