Invasive plants and control of water milfoil

Identification of the main species of invasive plants present in the lake

 

 

 

 

 

 

 

Invasive Plants Description

Eurasian water milfoil:

Because of it’s rapid growth, from the first days of Spring, Eurasian water milfoil create dense mats producing shade that inhibits the growth of other submerged plants. Eurasian water milfoil’s mats are known to become so dense as to displace all other plant species. (Environnement Canada, 2003).

Since Summer 2010, we have observed that the Eurasian water milfoil cluster near the rock island has spread widely towards the south, creating a major cluster of Eurasian water milfoil in lac Mercier.                              

A map identifying the Eurasian water milfoil growths is up-to-date, and available.           

    Map of lac Mercier 2015 showing dense milfoil clusters

Identification of the most important clusters, by the installation of buoys:

 Eurasian water milfoil spreads naturally when cuttings are spread by wind and waves, a process greatly worsened by the passage of watercraft.

The propellers of motorboats, pedal boats and even rowboats, slicing through Eurasian water milfoil dense mats, significantly accelerates the spread of this plant.

It is therefore very important to identify the sites of these growths, so as to avoid navigating through, or even swimming in them.

 

The milfoil cluster near the island in front of the beach was marked in July 2013 by two buoys. Another cluster was found in August 2013, and third buoy was placed.

 Facing expansion of the milfoil clusters, the Association decided to buy 3 more buoys in order to mark the enlargement of the milfoil clusters.

We have worked closely with the municipality to inform tourists and lake users of the need to reduce the risk of spreading of milfoil seeds.