Summary
Eurasian Water Milfoil (EWM) is an invasive aquatic species that has wreaked havoc on many lakes across the United States. While there are many different views on the best way to deal with it, there does seem to be consensus on one point. Once it has invaded your lake, you can never entirely get rid of it and you must have a sustainable plan for long term management.
Crystal Lake has a surface area of 9854 acres. Fortunately, our infestation is relatively small, six acres as reported by the Crystal Lake and Watershed Association, and we can learn a lot from the years of experience others have had managing Eurasian Water Milfoil. For example:
- Higgins Lake Property Owners' Association partnered with Restorative Lake Sciences and has removed 21 acres of EMW using a DASH boat (Diver Assisted Suction Harvester) purchased by the Higgins Lake Foundation, which resulting in "more targeted removal" not using any chemical herbicides.
- Lake Leelanau Lake Association, after "extensive use" of both biological and chemical controls since 2000, has concluded that "…the most successful means of control appears to be hand harvesting, which requires using trained divers to dig up the plants by their roots.."
Given the small amount of Eurasian Water Milfoil in Crystal Lake and the fact that there has only been limited herbicide treatment, we have the opportunity to find an effective path forward without committing to what the State of Michigan's 2019 Strategy on Eurasian Water Milfoil Management calls the "downsides regarding herbicide treatment of EWM" which requires repeated treatments, becomes costly over time and can "potentially induce a strain of chemically resistant EWM." There are a number of studies showing lakes treated with herbicides are much more likely to have chemically resistant hybrids of EMW than lakes than have had no chemical treatment.
Specifics
Crystal Lake Community has three areas of research about herbicides and Eurasian Milfoil 1) herbicides are a risk to human health, 2) herbicides make Eurasian Milfoil tougher to kill, and 3) other lake associations have found herbicides to be ineffective.
Concern about the serious threats to human health from application of herbicides is of PRIMARY concern. This threat has been cavalierly dismissed by the proponents of herbicides. Their rationale is that the amount used will be "small" and the herbicides will eventually be diluted and therefor "safe". They've also indicated that more than one application will be required, both in 2021 and in years to come. So their proposal basically boils down to herbicides forever, starting this year. The amount of herbicides required over time will not be small and therefor their use is unsafe, for those alive now and for future generations. Human health is our highest priority, we insist that any strategy for controlling aquatic invasives must NEVER endanger health.
Hybridization is caused by Herbicides
The supposed urgency about applying herbicides is justified by claims that the Eurasian Milfoil will hybridize and become resistant to herbicides. But the use of herbicides has been shown to cause hybridization!
Lake Associations Abandon Herbicides
Milfoil has been around for years, and other lake associations have found that non chemical strategies work best and far more cost effective long term. Crystal Lake can benefit from their experience, we do not have to repeat failed and dangerous herbicide strategies.