Weevils to wage war on weeds
The weevils are coming. About 12,000 of them. And Wayland is hoping that the tiny beetles bring a whale of an appetite.
The weevils (officially, Euhrychiopsis lecontei) will fly -- not on their own, but in a cargo container -- from a farm in Ohio where they are bred.
They are destined for Dudley Pond, as part of a federally funded pilot project to control Eurasian milfoil, an invasive weed that has choked fish and plant life on the pond and curtailed boating and swimming.
If everything goes as planned, the weevils will arrive this summer and, over the next three years, munch their way through the milfoil.
But not everyone in Wayland welcomes the weevils. Although the critters have already been put to work in other lakes and ponds around the state, including Wachusett Reservoir in West Boylston and Lake Waban in Wellesley, members of the Dudley Pond Association are divided over whether they will be sufficiently voracious.
Weevil advocates hope that the beetles will eliminate the need for chemical treatments, which kill other plants in addition to milfoil. Opponents say the water weeds will overrun the pond before the weevils have time to consume them. The debate has pitted the two factions against each other and has raised tensions between new and old pond residents.
''We've been talking about weevils for 10 to 15 years," said Judy Currier, recent president of the Dudley Pond Association. ''It gets to be very contentious."
Since the early 1990s, the town has paid as much as $30,000 every three years to have herbicides dumped and sprayed on the 86-acre pond to stop the weed. Citing the toll that spraying has taken on other native plants, some residents have also expressed concern about possible harm to humans, because the local water supply comes from aquifers near the pond.
Smaller than half a grain of rice, the beetle uses its sharp, beak-shaped mouth to gnaw holes in the stalk of the plant, killing it. Swimmers won't notice the tiny yellow and black bugs, even when they exist by the hundreds of thousands in a lake or pond, according to Bob Hartzel, a scientist at GeoSyntec Consultants of Acton, who obtained the weevil grant.
''I've done a lot of swimming with these bugs, and they're homebodies," Hartzel said. ''I've never come out [of the water] covered with bugs. They're on these plants like stink on meat."
Although they are much less expensive than chemical treatments, weevils are not a guaranteed success, Hartzel said. Sometimes weevils don't survive their first winter, requiring more to be added.
''You've got to hang out and just see what happens," he said. ''It requires patience."
The US Environmental Protection Agency OK'd a $42,150 grant for the project, which will pay for a three-year program of stocking the pond with weevils and monitoring their eating habits.
Hartzel is also monitoring a weevil project on Lake Waban at Wellesley College, which brought in 10,000 weevils last year. So far the results haven't been dramatic, but a college official remains optimistic. ''I think it's too early to be judgmental," said Patrick Willoughby, associate director of the college's physical plant. ''You can't expect immediate results, like with herbicides."
Wachusett Reservoir launched a pilot project with 10,000 weevils last year with a state grant. Ecologist Dave Worden, who oversees the project for the state Department of Conservation and Recreation, said he remains hopeful, even though after two years, the weevils haven't been as effective as had been hoped.
''These things take time," Worden said. ''We think 10,000 is enough."
Tim Simmons, a restoration ecologist with the state Department of Fish and Game, said the beetle is indigenous to Massachusetts. Simmons pointed out that while they eat only milfoil, the remote possibility remains that they would change their eating preferences
''Once these things are out and successful, you don't get them back," Simmons said of the weevils. He also raised the possible problem of the milfoil being followed by another invasive plant.
Robert Creed, an associate professor of biology at Appalachian State University in North Carolina, researched weevils as a postdoctoral student at Middlebury College in Vermont and found them to be effective.
''With just 1,000 weevils in a lake, you can build up a population pretty quickly," he said. ''And I've seen them destroy plants."
Lili Scheider, an environmental engineer who moved to a house on Dudley Pond in 2000, said she hoped that would happen on Dudley Pond. A member of the surface water committee of the Wayland Conservation Committee, Scheider criticized the use of chemicals as too expensive and a potential threat to drinking water.
''The weevils can be cheaper, if you get them established," she said. ''It's worth a try."
Scheider said the weevils may not succeed, and if they don't, there are other alternatives. Town officials could pay for milfoil harvesting that would pull the plants out at the root, or investigate importing carp, a voracious fish that eats milfoil.
Ellen Egnet disagreed. Thanks to herbicide, Egnet said, she and her husband were able to use their pontoon boat without the rudder becoming entangled in milfoil.
''They did the sonar and everything was absolutely fabulous," she said. "But . . . every so often you have a new group of people that come in and change things."
Thomas McGreenery, past president of the Dudley Pond Association, called the weevils ''a complete waste of time."
He resigned as president of the pond association last year in protest over ending the herbicide treatment.
He said the weevil proponents are ''environmental terrorists" who risk letting the pond become an overgrown swamp.
''The only viable method . . . is the herbicide," he said. ''It's been used on the pond four or five times, and it does a wonderful job."
Currier, the past president of the pond association and a supporter of the weevil project, tries to strike a diplomatic note.
''There are two factions and a lot of us in the middle, willing to try anything," Currier said. ''We can never solve the problem, but we want to find ways to control it."
Megan Woolhouse can be reached at woolhouse@globe.com. 