Parrot Feather Watermilfoil

Myriophyllum aquaticum

© John M. Randall/The Nature Conservancy


Description

Aquatic weed with feather-like leaves arranged around the stem in whorls of four to six. Has both submersed and emergent leaves, with submersed leaves often confused with Eurasian watermilfoil. The emergent leaves are stiff and dark green, growing up to a foot above the water surface, giving the appearance of small fir trees - the most distinctive characteristic of the plant.

Habitat

Freshwater lakes, ponds, streams, and canals; appears to be adapted to high nutrient environments

Distribution

Coastal lakes and streams in Washington, and the southwest Washington portion of the Columbia River; western Oregon; Latah, Nez Perce, and Gem counties, Idaho

Impacts

Changes physical and chemical characteristics of lakes and streams, alters ecosystems by shading out algae that is important to the food web, provides ideal habitat for mosquito larvae, clogs waterways, impedes recreation

Dispersal Methods

Plant fragments, often spread long distance by boat activity, and intentional planting

Prevention

Look for the fir tree-like emergent leaves.

Listings

Not listed

Factsheets

Washington State Department of Ecology Fact Sheet

Photos

http://www.forestryimages.org/search/action.cfm?q=parrot%20feather

Distribution Map

Distribution in Oregon
Distribution in Washington
Distribution in Idaho

Other Links

Foiling Watermilfoil by Marcia Wood - Article from the USDA Agriculture Research Service Website
Massachusetts Department of Conservation and Recreation Fact Sheet (Good images for identification)

CWMA Warnings

Mid-Willamette