Egeria densa


Similar Species
- Common waterweed Elodea canadensis
- Hydrilla Hydrilla verticillata
History
- Has been sold around the world as a popular plant for freshwater aquariums; sometimes discarded into waterbodies and becomes established
Characteristics
- Submersed, rooted, perennial plant
- Stems reach 6 ft (2 m) in length, branch profusely at the water surface, and form thick mats
- Stems have whorls of 4-6 small leaves, which vary from 0.5-1.5 in (1.25-3.8 cm) in length
- Inconspicuous flowers with 3 white petals and 3 green sepals, at or above the water surface
- Often confused with hydrilla (Hydrilla verticillata), but lacks conspicuously toothed leaf margins
Habitat
- Lakes, rivers, streams in depths to 20 ft (6.1 m)
Known Distribution in the Northeast
- Connecticut, Massachusetts, New Hampshire, New York, Rhode Island
- Native to South America
Impacts
- Forms dense stands that crowd out native aquatic plants and degrade wildlife habitat
- Can impede fishing, swimming and boating
- Restricts water movement, causing sedimentation and affecting water quality