Invasive Species

We must always be vigilant and protect our lake against invasive species.

2018 – Aquatic Plant Report

Lake Louisa health report

It appears that Lake Louisa is still free of Eurasian Milfoil this summer.
Good news!

But this doesn’t by any means signify that vigilance should be relaxed! It is very important that everyone learns to identify the plant and report any finding of it. When an invasion is spotted early enough, it can be halted.

Look for it in shallow bays or shoals, between 0 and 15 feet deep. Mostly around the 4 to 10 feet range.

The lake is very rich with aquatic plants (non-invasive), and this is good. There is an amazing variety, dominated by the pondweed family.

As for algae blooms (algae and aquatic plants are 2 things! Algae is mostly microscopic): they are ALWAYS the result of an overabundance of nutrients in the water. And this overabundance is very often the result of human activity. (Inadequate septic installations, devegetalization of shores (allowing nutrient-rich run-offs after rains), boats producing big waves in shallow water (this stirs-up sediment and puts back in the water column nutrients that were ‘’buried’’ in sediments).

Also, for the same reasons, potted decorative flowers or plants should not be present on docks or shore. The nutrients and fertilizers in the soil will get in the water with rain and directly feed algae.

In one summer, according to one of our biologist friends, a big potted plant can leak out the equivalent of the nutrients contained in 100 gallons of raw sewage water!

No need to embellish the lake: you chose to live there because it was already beautiful! Leave it to nature, she knows best.

Have a wonderful end of summer; this one was gorgeous!
Learn to identify aquatic flora and stay alert!

Jean-Louis Courteau
CIEL (Centre d’Interprétation des Eaux Laurentiennes)
47 rue de l’Église
Lac-des-Seize-Iles, Qc.
J0T2M0
centreleciel@gmail.com