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Eurasian Watermilfoil

Scientific Name

Myriophyllum spicatum L. (ITIS)

Common Name

Eurasian watermilfoil, spiked watermilfoil

Native To

Europe, Asia, and North Africa (Eiswerth et al. 2000)

Date of U.S. Introduction

Exact date unknown; between the 1880s and the 1940s (Eiswerth et al. 2000)

Means of Introduction

Unknown, possibly through the aquarium trade or transport of watercraft (Nichols and Shaw 1986)


Crowds out native species (Smith and Barko 1990)

Eurasian watermilfoil

Eurasian watermilfoil, infestation; dense canopy on surface at Cayuga Lake (New York)


Photo by Robert L. Johnson; Cornell University

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  • Spread the Word, Not the Weeds

    • Feb 22, 2021
    • USDA. Blog.

    • Deceptively delicate and fragile in appearance, the Eurasian watermilfoil forms thick mats in shallow areas of a lake, quickly growing and spreading to block sunlight, killing off native aquatic plants that fish and other underwater species rely on for food and shelter. In North America, the plant threatens the diversity and abundance of native plants as well as the ecological balance of lakes and ponds, which in turn adversely affects recreational opportunities. If left unchecked, invasive watermilfoil will spread through a lake, or even to other lakes by transmission. An expert team of USDA Forest Service divers with invasive species and aquatics expertise is focused on rooting out the plant.

Distribution / Maps / Survey Status


Selected Resources

The section below contains highly relevant resources for this species, organized by source.

Council or Task Force
Federal Government
International Government
State and Local Government