Myriophyllum spicatum, or Eurasian Water Milfoil (EWM), is an invasive plant that has unfortunately entered our lakes and rivers. EWM can form very dense patches that obstruct recreational activities such as swimming, boating, and fishing, competes with native vegetation, and can lead to damaging changes in the ecosystem.
The Jemseg Grand Lake Watershed Association has been mapping the spread of EWM in our area and raising awareness of this issue since 2022. This work has been sponsored by the Environmental Trust Fund (2022-2025), Wildlife Habitat Canada (2026-2027), and supported by the New Brunswick Invasive Species Council, and our members and volunteers.
If you think you have found Eurasian Water Milfoil…
– Ensure that it is EWM before acting. There are other Milfoil species and species that strongly resemble them. Consult an identification guide or upload representative pictures to iNaturalist; perhaps a community member will identify your sighting.
– Do NOT attempt to remove it. EWM can spread through fragments, and pulling plants can often cause pieces to break off. Watercourse and Wetland Alteration Permits may also be required when removing aquatic vegetation. Avoid disturbing the plants, including with boat propellers.
– Any collected fragments should be disposed of on land, far from where water may flow and carry it back to the waterway.
– You can report sightings to contribute to the ongoing monitoring efforts, or join citizen science projects like iNaturalist (you can join our iNaturalist Project here!). If it is in our watershed area, you can email us at [email protected] with the location coordinates and pictures of what you saw.
– ALWAYS thoroughly clean your boats and other equipment if moving between bodies of water, and even areas of the lake, to prevent accidental spread. This can also help prevent the spread of other species too!
Map
The below map represents our findings, as recorded by designated surveyors, and does not reflect the true extent of the spread of Eurasian Water Milfoil in the area. Priority locations are identified when making survey plans on a yearly basis.
Workshops
The Jemseg Grand Lake Watershed Association sometimes holds free public workshops on how to identify and survey EWM in the late summer. Follow our social media accounts (Facebook or Instagram) or contact us by email for more information.
Removal Efforts
Due to the size of Grand Lake and its tributaries, complete removal of EWM is virtually impossible, but the Jemseg Grand Lake Watershed Association has done some projects focusing on managing areas of the lake. Due to the size of the Lake, properties of EWM, and importance of non-target species, hand-removal is currently our recommendation for priority patches of EWM. See our Reports and Publications below for our findings, and watch the Webinars for discussion on the feasibility of removal techniques.
Associated Reports and Publications
– Water Quality Monitoring, Education, and Climate Change Adaptation in the Jemseg-Grand Lake Watershed: Section 3 (2026)
– Eurasian Water Milfoil in the Grand Lake (Slideshow featured in Webinar) (2025)
– Water Quality Monitoring, Education and Climate Change Adaptation in the Jemseg Grand Lake Watershed: Section 3 (2024)
– Jemseg Grand Lake Watershed Association 2023 Annual Report: Section 4 (2023)
– Ecosystem Education and Outreach in the Jemseg Grand Lake Watershed: Section 3.5 (2023)
– Finding and Reporting Eurasian Water Milfoil (2022)
Learn more from the experts on our Youtube channel!
