Barbara Fradkin, Sharbot Lake Property Owners Association | Jul 25, 2018
Our beautiful lakes are having enough trouble these days without the threat of an invasive aquatic weed that came to this country as an aquarium plant and is now trying to take over.
Eurasian water milfoil has been spreading rapidly through central Canadian waterways and has already been detected in some of the lakes in our region. As it moves in, it crowds out other aquatic plants, endangers fish habitats, and destroys the quality of the lake for both fishing and watersports. Once it gets in, it’s difficult to get rid of, so it’s best to keep it out in the first place. However, even if it’s established in a lake, control measures can help limit the spread.
Native aquatic plants are an important part of a lake’s health, and this invader looks a lot like native northern milfoil, so identification is key. It’s a perennial green plant that forms a dense, tangled mat from which tall spikes rise. It has feather-like green leaves that circle a long stem in groups of four or five. Each leaf has twelve or more thread-like segments, whereas the native species has eleven or fewer.
It blooms in late July to early August and produces tiny reddish flowers, which grow on spikes five to twenty centimetres long and rise above the water.
The plants grow from seed, but also from fragments broken off existing plants, which is why it spreads so fast. Fragments are easily created by wind action, swimming, raking or cutting, and by the chopping action of boat propellers. Tiny fragments can travel on boats, motors, trailers, and personal gear from one lake to another.
Controlling the spread is up to every lake user. The lake and anglers associations have taken the lead in producing signs and educational pamphlets. Waterfront owners and users should watch out for the plant on their own area and consult experts on how to safely remove or reduce it. Cutting or raking it will only cause more plants to grow from fragments.
The Sharbot Lake Property Owners’ Association has recently begun checking out potential sightings on the lake and will be posting signs at public launch sites and docks. Other local associations can do the same. So far, the invader has not been confirmed in Sharbot Lake, but all bodies of water are at risk.
Here are steps each of us can take.
Don’t cut the weeds, and if you pull them out by hand, take care to remove all parts from the lake and place in the trash. Avoid driving motorboats through infested areas. When you travel from one body of water to another, inspect and remove all visible aquatic material and mud from boats, motors, trailers, etc. Drain all water from boat, including live well, bilge, and motor. Do not dump the water in the lake. Wash watercraft with high pressure or hot water, or dry for 5 days. Check, clean and dry all personal and fishing gear. Dispose of bait and bait water away from lake. Never release plants or animals, into the lake unless they came from that lake.
More information and guidance can be obtained from your local conservation authority or at http://www.invadingspecies.com/eurasian-water-milfoil/