SafePlants

Canadian Waterweed (Elodea canadensis)

Elodea canadensis, commonly known as Canadian waterweed, is a perennial aquatic plant found in various freshwater habitats. It is often sold as an "oxygenating plant" or "pondweed."

Common Names

• Canadian waterweed
• Canadian pondweed
• American elodea
• Common elodea
• Anacharis
• Canada waterweed
• Canadian water pest
• Common waterweed
• Ditch moss
• Water-thyme

Taxonomy and Nomenclature

• Scientific Name: Elodea canadensis Michx.
• Family: Hydrocharitaceae (Tape-grass family)
• Synonyms:
  • Anacharis canadensis Planch.
  • Anacharist canadensis (as mentioned)
  • Philotria canadensis (as mentioned)

Distribution and Habitat

• Native to most of North America and South America.
• Found in lakes, ponds, canals, and slow-flowing water.
• Has naturalized in Asia, Africa, Australia, and Europe.
• First report in Europe was in Waringstown, Co. Ireland.
• Occurs throughout most of Great Britain (GB).
• Identified in areas in Alaska, including Eyak Lake in the Cordova area.

Ecological Role

• Considered an invasive plant in several regions.
• Can form dense mats in shallow ponds and slow-moving waters, potentially obstructing lake navigation.
• Spreads rapidly, especially via improper disposal of aquarium water.

Morphological Characteristics

• Perennial aquatic herb with branching stems.
• Submergent macrophyte.
• Grows rapidly.
• Sometimes reaches the water surface.

Interactions with Other Organisms

• Provides habitat for many small aquatic animals, which fish feed on.
• Serves as food for the Water Veneer moth (Acentria ephemerella).

Quirky Facts

• The name Elodea comes from the Greek word "eleios" (or "heleios"), meaning "of the marsh or meadow." The epithet canadensis comes from the Latin, meaning "of Canada".