Graves Lovell, AL DCNR

Eurasian Water-Milfoil

Myriophyllum spicatum L.
Water milfoil family (Halogoraceae)

Origin: Eurasia and Africa

Introduced accidentally from Eurasia in the 1940s, Eurasian water-milfoil possibly escaped from an aquarium or was brought in on a commercial or private boat.

Distribution and Habitat
Eurasian water-milfoil occurs in at least 33 states east of the Mississippi River and has recently been found in Colorado. It is abundant in the Chesapeake Bay, the tidal Potomac River and several Tennessee Valley reservoirs. Typical habitat includes fresh to brackish water of ponds, lakes, slow-moving streams, reservoirs, estuaries and canals. It is tolerant of many water pollutants.

Ecological Threat
Water-milfoil tends to invade disturbed areas and does not typically spread into undisturbed areas where native plants are well established. It can form large, floating mats of vegetation on the surface of lakes, rivers and other water bodies, that impede water traffic and reduce light for native aquatic species. It thrives in areas that have been subjected to natural and man-made disturbance.

Description and Biology

Alison Fox, UFL

Mike Naylor, MD DNR

Prevention and Control
Large harvesting equipment can be used to mechanically remove Eurasian water-milfoil in larger areas; a sturdy hand-rake can be used for smaller areas. Other options include manipulation of water level, use of water colorants or floating aquatic plants to reduce light penetration, physical barriers and chemical control. Potential impacts to existing native aquatic plant species should be evaluated carefully before using any of these techniques.

Native Alternatives
Aquatic plant species are difficult to tell apart to the untrained eye. Contact your state natural resource agency, native plant society or other resource (see References) for assistance.


Return to the Table of Contents | Download a PDF of Plant Invaders of Mid-Atlantic Natural Areas

Comments, suggestions, and questions about the website should be directed to the webmaster.
Last updated:11-Nov-2010