Our pilot-project aimed at halting alien grasses is slowly taking root. The alien grasses have been identified on a map twice since 2002. With this information, we are actually updating our data. The lake has been crossed once, in its south-west area by an expert from RAPPEL, Jean-François Martel, along with our intern Agnès Grandmaison. The good news is that we saw no significant increase since 2006.
Our initial findings, indicate that if we intervene, it will be in the more calm and well-defined bays, for example Slack Bay. We are not at this stage yet. There are many steps before we get there, we must finish the feasibility and determine the interest of the operation. We will also require multiple necessary authorizations. In the interval, we are closely monitoring a similar experiment done at Lake O’Malley. Agnès Grandmaison attended the first cuts a few weeks ago. Her report gives a good overview of the project.
It is under a radiant sun that volunteers gathered on July 2 at Lake O’Malley, in Austin. They were there to participate in the cutting of an invasive aquatic plant; Eurasian watermilfoil. Originating from Europe, this plant invades all types of soil and owns four reproduction means, of which the most efficient: fragmentation. It becomes a plant that grows quickly and aggressively encroaching on the territory of native species.
First a swimmer with a mask and snorkel explores the places invaded by milfoil and defines the cutting zone.
Curtains are then spread out to control the propagation of milfoil which will float on the water surface once cut.
The cutting can then begin which is done with a knife one meter wide. The boat wanders within the limits of the area, from outside to inside. At this stage, it is necessary to have a good visibility in the water so weather conditions play an important role. The milfoils are cut to within a foot of their base to avoid stirring the cutting of an invasive aquatic plant; sediments in the bottom of the lake.
Simultaneously, the aquatic plant cuttings are harvested into canoes and kayaks. The cargo is cleared on the shore and will serve as compost. The goal is to leave as little pieces as possible. The result of the operation depends on it.
The July 2nd intervention being a pilot-project, it is difficult to predict the efficacy. The cutting is only one barrier to the invasion. It does not constitute in any way a total eradication. We now need to monitor the area to see the evolution over the summer.