Myriophyllum aquaticum

Do you think you have discovered an aquatic invasive species?

  1. Do not return the species to the water.
  2. Note the exact location (GPS coordinates) and the observation date.
  3. Take photos.
  4. Take note of identifying features.
  5. Report an Aquatic Invasive Species, depending on where you are.
  6. What you can do to reduce the risk.


Identifying features

Parrotfeather has both submerged and emergent leaves. Its feather-like leaves are arranged around the stem in whorls of four to six. The submersed leaves are 1.5 - 3.5 cm long. The emergent leaves are 2 to 5 cm long with 16 to 18 divisions per leaf. The emergent stem and bright green leaves grow up to a foot above the water. White flowers are known to occur in North America.

Where it has been found

Populations have been found in the Fraser Valley of B.C.

Ecological and economic impacts

Parrotfeather can alter native vegetation and shade natural algae that serve as the basis for the aquatic food chain. Parrotfeather can cause problems in irrigation and drainage canals and clogs waterways, which can restrict recreational activities such as boating, swimming and fishing. The dense growth of this plant creates stagnant waters, increasing breeding grounds for mosquitoes (some of which can carry diseases).

Origins and mode of arrival

Native to South America

Mode of dissemination

Parrotfeather is an example of a plant introduced for use in indoor and outdoor aquariums and water gardens that has escaped and spread to natural aquatic ecosystems.

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