Place of origin
Originally from Eurasia and North Africa, Eurasian watermilfoil (Myriophyllum spicatum) was introduced to North America in 1961 in Lake Erie, Ontario. To our knowledge, Eurasian watermilfoil is currently not present in Alberta.
Prefers shallow water but can root up to 10 m in depth.
- Perennial, submersed; flowers are very small, reddish and held above water on a flower spike.
- Usually 12 to 21 closely spaced leaflet pairs per leaf.
- Feather-like leaves collapse around stem when out of water.
- A single segment of stem and leaves can form a new colony.
- Plant does produce seeds but germination rates are usually poor.
- Stem fragmentation and underground runners allow this plant to reproduce rapidly.
- Forms large, floating mats that prevent light penetration into waterbodies, out-shading native plants and reducing oxygen levels when decomposing.
- Out-competes native milfoils.
Help stop the spread of invasive plants
Report aquatic invasive species:
Learn more about identifying and preventing invasive aquatic plants:
- List of prohibited species
- Aquatic Invasive Species Pocket Guide
- ALMS Field Guide to Aquatic Plants
- Invasive Plants (Alberta Invasive Species Council)
Spread the word about the threats invasive plants pose:
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