Invasive 'zombie plant' species is wreaking havoc across Ontario lakes

A pesky invasive plant species is wreaking havoc across Ontario lakes, and aquatic experts say its complete eradication is unlikely. 

Eurasian watermilfoil (Myriophyllum spicatum) — also known as the "zombie plant" — gets its nickname from its ability to come back to life even after being severed from its root. 

The plant was first found in Ontario in Lake Erie in 1961 and has since spread throughout all of the Great Lakes, the St. Lawrence River, as well as the inland lakes throughout the province. 

The presence of the troublesome plant has only grown stronger, as evidenced by the almost daily sightings reported by Ontario users last summer through the social network biodiversity app, iNaturalist. 

Eurasian watermilfoil is an invasive aquatic plant that spreads rapidly and multiplies when it's cut by a boat propeller. For the first time this species has been spotted in the St, John River. Avoid milfoil while boating and clean, drain, dry after use to avoid spreading! pic.twitter.com/R4BzQLo9Ex

— Invasive Species Ctr (@InvSp) April 9, 2018

The perennial aquatic plant grows under the water surface and is most commonly found in water anywhere from one to three metres deep in lakes, rivers, and ponds, although it has the potential to take root in up to 10 metres of water. 

In July and August, the plant blooms small reddish flowers that rise above the water, although the situation is anything but pretty below the surface. 

Eurasian watermilfoil grows in thick, dense mats that crowd out native species, threaten biodiversity, and deoxygenate the water when decomposing, effectively killing other aquatic species. 

The plant can also damage boat motors, impact fishing and swimming, and increase mosquito habitat. 

To prevent its spread, the Invasive Species Centre recommends avoiding boating through invaded areas, washing all recreational equipment, and never releasing or composting unwanted aquarium vegetation. 

You can also help prevent its spread by inspecting your boat, trailer, and equipment after each use, and removing all plants, animals, and mud before moving to a new waterbody.