Ossipee — June 2, 2005 — The spread of invasive plants and animals in our lakes is an issue that affects everyone who lives in Northern New Hampshire.
When variable milfoil takes hold in the shallow waters of a lake or pond, it can rapidly push out native plants, and fish, and become a nuisance for boaters, swimmers and others who enjoy recreation on the lake. Clear pools of water become thickly choked with it and start to resemble swamps more than lakes.
Property values around lakes infested with the weed can decrease as much as 20 percent, and with that towns can lose a significant source of tax revenue. Tourists find vacationing on such lakes less attractive and go elsewhere. And most people who live in this region depend directly or indirectly on tourism for their income.
Last week, we reported on efforts to clean up milfoil on Ossipee Lake by hand-pulling the plant. This week we have a story about efforts to dislodge the weed from Back Bay in Wolfeboro through a relatively new “designer” herbicide that targets this particular plant. No single technique has proven effective in eradicating the plant because the smallest piece can be spread and re-colonize a water body. The most effective method remains prevention.
Variable milfoil is the most prominent current threat to our lakes and streams. But it is not the only one. Eurasian milfoil, hydrilla, fanwort, Brazilian elodia, water chestnut and zebra mussels have all been found in New Hampshire or neighboring states and pose threats.
Milfoil has been steadily spreading for decades after gaining a toehold in Winnipesaukee in the early 1970s. Today it is found on at least nine lakes and ponds in Carroll County (38 statewide), including Winnipesaukee, Ossipee and Squam Lakes. Other lakes, including Silver Lake in Madison and Chocorua Lake in Tamworth and Conway Lake in Conway, remain clear. The question is, for how long.
The state is fortunate to have the Lake Host Program, started by N.H. Lakes Association, to make people aware of the problem and what they can do to stop its spread. The U.S. Environmental Protection Agency recently recognized the Lake Host program with an environmental merit award for its efforts, noting that statewide the program has already had 27 saves.
The Lake Host program has already had success on Silver Lake, where milfoil was prevented from coming into the lake by the sharp eyes of volunteers.
Another program that helps fight the spread of exotic plants is the Weed Watchers program, which has had some success identifying new infestations of milfoil on Ossipee Lake. Volunteers with that program check a section of the lake on a regular basis, say once a week, to watch for the spread of the plant. More volunteers are needed for this program. What can you do to help:
Never dump fish tanks or release fish or plants into a body of water. It is believed that the spread of some exotic plant species started that way.
If you are a boater, make sure your boat is clean and clear of any plants before you put it into a body of water and when you take it out again. Drain all the water from intake systems and equipment.
Support your local lakes association or volunteer with the Lake Host or Weed Watchers programs. If you live on Ossipee Lake and want to volunteer for Weed Watchers, contact June D’Andrea, coordinator, at 539-1643.
You can learn more about milfoil and other exotic species on the state website: www.des.state.nh.us/WMB/ExoticSpecies.