Eurasian watermilfoil (EWM) is an aquatic invasive plant that can cause a lot of problems once established in a lake. One non-chemical method controlling EWM is biological control. Using the Milfoil Weevil (Euhrychiopsis lecontei) is one of these methods.


In 2011-2014 we conducted a pilot study to test whether volunteers could successfully raise their own weevils on a mass scale. Read more about the mass rearing method in Chapter V of our Biocontrol Manual.


Even simpler and cheaper:  What if we could allow the native weevil population to reproduce naturally in the lake with no predators picking them off?  Our current experiments test the efficacy of predator exclusion cages in Lake Joanis, Schmeekle Reserve, Stevens Point.  With the help of funding from WDNR and volunteer labor from the awesome students at Wisconsin River Academy charter school, we are monitoring how the weevils do when fish predation is not an issue - no weevil stocking required!  See our latest report here. 

Want to know more about weevils?  Our biocontrol manual has pretty much everything you want to know about weevils... whether you're a lake resident or a lake management professional!  Get the PDF here.

Native Weevil_likely Phytobius leucogaster_foun