Invasive Alien Plant Species of Virginia Parrot’S Feather (Myriophyllum Aquaticum (Vell.) Verd.)

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Invasive Alien Plant Species of Virginia Parrot’s Feather (Myriophyllum aquaticum (Vell.) Verd.)

Description introduction, the plant has spread Parrot’s feather, a member of the throughout the southern United water-milfoil family (Halo- States and northward along both ragaceae), is a herbaceous aquatic coasts. It appears to prefer warmer, perennial that gets its name from the milder climates and has spread feather-like appearance of its gray- quickly via plant fragments through green leaves. The leaves are waterways and drainage systems arranged around the stem in whorls and intentional plantings. of four to six, and may be submerged or emergent. Stiff, bright green, Threats emergent leaves are 1 to 2 inches Because of its appearance and ease long with 10 to 18 segments per leaf. of cultivation, parrot’s feather has The stem and leaves can grow up to been used extensively in both indoor a foot above the water surface, and outdoor aquaria and as a popular giving the appearance of small fir water garden plant. It has escaped trees. The submerged leaves are cultivation, however, and while limp, but the stems are stiff and very parrot’s feather may provide cover vigorous. When attached to a bank, for some aquatic organisms, it can seriously change the physical the plant can extend several yards Parrot’s Feather (Myriophyllum across the water. Male and female characteristics of lakes and streams. aquaticum (Vell.) Verd.) flowers are on different plants, but The shade from dense infestations plant parts, using mechanical only the female plants have been can alter aquatic ecosystems, and the controls such as cutting and found in North America. Besides thick growth can clog irrigation and underwater rototilling will tend to parrot’s feather and another non- drainage canals. Many enhance its rate of spread. Although native, Eurasian water-milfoil municipalities are spending it is considered by some to be (Myriophyllum spicatum), eight hundreds of thousands of dollars susceptible to herbicides, achieving native species of Myriophyllum are annually to control parrot’s feather. complete control is difficult. The found in eastern North America. Flooding, drainage and irrigation emergent stems and leaves have a Consult a botanist to confirm problems, and increased mosquito waxy cuticle that requires a identification before initiating any populations are all legacies of this surfactant for penetration. control measures. single aquatic plant. Yet it continues to be a challenge to persuade garden Surfactants, however, are harmful to Habitat centers to remove it from their most aquatic organisms. Use Parrot’s feather is a native of the inventories. herbicides approved for use in Amazon River and was introduced wetlands and follow the label to North America in the Control directions. One nursery owner killed Washington, D.C., area around Because parrot’s feather spreads a severe infestation in his irrigation 1890. However, since its rapidly through fragmentation of pond by drawing down the pond in

For more information, contact the Department of Conservation and Recreation or the Virginia Native Plant Society. Virginia Native Plant Society Blandy Experimental Farm Route 2, Box 214 Boyce, VA 22620 (540) 837-1600 217 Governor Street, Richmond, VA 23219 (804) 786-7951; http://www.state.va.us/~dcr/vaher.html http://www.hort.vt.edu/vnps/ Jim Gilmore, Governor • John Paul Woodley, Jr., Secretary of Natural Resources • David G. Brickley, Director, Department of Conservation and Recreation Invasive Alien Plant Species of Virginia Parrot’s Feather (Myriophyllum aquaticum (Vell.) Verd.) winter and freezing the plant out, References Management Methods. 16 Oct 1998. apparently completely eradicating it. Couch, R. and Nelson, E. 1991. The Exotic . Proceedings from the states’ management Illustration reprinted with permission programs-monitoring and lake assessments, from The Illustrated Companion to This fact sheet was substantially 5-11. prepared by Barry Reynolds to Gleason and Cronquist’s Manual: Illustrations of Vascular Plants of fulfill course requirements at Washington Department of Ecology Water Quality Program. 1998. Invasive Northeastern United States and Adjacent Virginia Polytechnic Institute & nonnative freshwater plants: Parrot Canada, copyright 1998, The New York State University. feather milfoil. Aquatic Plant Botanical Garden.

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