2015 Milfoil Season Wrap-Up

One of 4 Lake Dunmore/Fern Lake  Milfoil Harvesters

One of 4 Lake Dunmore/Fern Lake  Milfoil Harvesters

The 2015 milfoil season is all done except for the paperwork. We had a big task and we prepared well and worked hard. Every year, the milfoil has expanded in greater and greater amounts. It has been our challenge to try to keep up. As the milfoil growth has increased exponentially, our growth has been closer to linear. What this means is that unless something changes in either the plant growth, or the way we deal with it, we will become overwhelmed.  This was the year we became overwhelmed.  We built a fourth harvester, we recruited the largest crew we’ve ever had, we worked more hours than ever, yet in the end, we had more milfoil this September than last. I can’t imagine what it would have been had we not expanded operations!

Milfoil harvesting is done under tight government restrictions. The state is responsible for the quality of our lakes. As such they have only approved a certain number of methods to eliminate milfoil. We have tried most of them, and for Lake Dunmore and Fern Lake, mechanical suction harvesting has been the most cost effective technique. Still, it’s expensive and not that environmentally friendly. It creates fragments which can reseed themselves (even though we go to great lengths to recapture them), and it invariably disturbs native plants in the  vicinity of milfoil.  Another important consideration is money. For the past 6 years, what was substantial support from the state has become volatile and declined from 75 percent to approximately 30 percent of our needs. The state is under fiscal tremendous pressure overall and from all the other lakes in the state undergoing similar infestations. This led to our Lakes Alive - Now & Forever capital campaign designed to meet near term and long term needs. The reserve funds earmarked for the near term made it possible for the expanded efforts this past year mentioned above. In the future, the projected endowment interest income of approximately $50,000 will help make up for the reduction in state support.

Yet the milfoil continues to expand. We have reached the point where suction harvesting the densely formed patches of milfoil is not the most economical solution. We had long suspected that this scenario would happen. Therefore, we decided that when it did, that we would have to employ other tools, in conjunction with continued suction harvesting. After much debate and consideration of alternatives, we have applied for an herbicide permit from the state. Of course this is not a panacea; we will not saturate the lakes with it. (The state would not allow this anyway.) What it will do is allow us to quickly and efficiently eliminate the huge forests of milfoil which have occupied our resources and allow us to search and destroy the dangerous new growth. We used a similar tact this summer as a stopgap measure; we isolated the main forests with buoys, asking the public to avoid those areas and protect them from their  propellers to minimize their spreading.

If approved, which is expected, the chosen herbicide would be applied on a limited basis directly on the high density milfoil growth (e.g. the North Cove and along the spine). It is target-specific for Eurasian milfoil and has no off-target impacts on other plants, fish, wildlife or humans when properly used. Our application is for 5 years, allowing an application of the herbicide twice in 5 years. The applications would be spot treatments, heavily monitored by the state before during and after the application. The application would be in the spring, before heavy use of the lakes. As a precaution, use of the lake and lake waters (e.g. for drinking) would be restricted for several days after application.

When we get the permit, the cost per acre for herbicide will be significantly lower than the mechanical harvesting, allowing our program to better fit within our budget   again.  The exact herbicide used will be dictated by the state, but the ones they’ve approved have a decade’s long history of safety. All in all, our season went according to plan, we had moderate success keeping the enemy at the gates while we readied our weapons. With the expected herbicide permits in addition to continued suction harvesting, we expect we’ll start to stem the tide next year.