Myriophyllum aquaticum

Myriophyllum_aquaticum_By André Karwath
Photo by André Karwath, via Wikimedia Commons

Synonyms: Enhydria aquatica, Myriophyllum brasiliense, M. proserpinacoides

Common names: parrotfeather; Brazilian watermilfoil; parrotfeather watermilfoil; thread-of-life;

Myriophyllum aquaticum (parrotfeather) is a stout aquatic perennial (family Haloragaceae) that forms dense mats of intertwined brownish stems (rhizomes) in water. Myriophyllum aquaticum can be found in freshwater lakes, ponds, and canals with slow-moving waters in northern and central California. This invasive plant may compete with native aquatic plants, eliminating them or reducing their numbers in infested sites. It forms dense mats that can entirely cover the surface of the water in shallow lakes and other waterways. The species does not produce viable seed and its distribution is limited to vegetative dispersal mechanisms.

Rating: High

Cal-IPC Resources

  • Plant Assessment Form - Information gathered by Cal-IPC on the impacts, rate of spread, and distribution of invasive plants in California. Does not include management information.
  • CalWeedMapper - Statewide maps, climate models, and reports.
  • Cal-IPC News - Our quarterly newsletter. Each issue is available as a pdf.
  • Cal-IPC Symposium Proceedings - Presentations and papers from our annual Symposium.
  • Don't Plant a Pest! - Select your region to find non-invasive alternatives to ornamental species. Also see our statewide brochure on trees.

Other Resources

Symposium Presentations

  • Anderson, L. (2003). Aquatic weeds: Policy, prevention, and control. California Invasive Plant Council Symposium 2003. Kings Beach, California, CA.
  • Connick, S. and M. Gerel (2004). Partnering to prevent invasions of plants of horticultural origin. California Invasive Plant Council Symposium 2004. Ventura, CA.

Cal-IPC News Articles

  • Connick, S. and M. Gerel (2005). Don't sell a pest: A new partnership to prevent plant invasions through horticulture. Cal-IPC News. 13: 4-5,14.