Eurasian watermilfoil is an aquatic invasive plant related to native milfoils, introduced from areas of Europe and Asia. The plant was originally introduced to the East Coast of the United States in the 1880s and worked its way across the country over the next century, showing up in Lake Tahoe sometime in the 1980s.
Key characteristics of Eurasian watermilfoil include:
- Feather-like leaves that are typically flat at the end (see image above)
- 13 or more "leaflet" pairs per leaf -- all native milfoils have fewer than 13 leaflet pairs
- A red or green stem that typically collapses out of water -- native milfoils tend to hold their shape out of the water
If you find a plant that fits this description, especially if it is a fragment floating on the water’s surface, it is most likely Eurasian watermilfoil.
See below for a detailed description of Eurasian watermilfoil from our Eyes on the Lake ID guide. If you sign up for a group training you will receive a full ID guide to help you in the field.
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Top left Eurasian watermilfoil photo by Joseph DiTimaso, PhD.