Castleton rejects use of herbicides for Lake Bomoseen

By Katy Savage

The Castleton Select Board unanimously decided Monday, May 9 to oppose the use of herbicides to control milfoil in Lake Bomoseen.

Castleton joined the towns of Hubbardton and Fair Haven, which have also publicly opposed herbicides after outcry from residents. Castleton board members planned to write a letter urging the Lake Bomoseen Association and the state to control milfoil, an invasive species, without the use of herbicides.

The Select Board’s decision came after about 150 people attended an informational meeting at Castleton University on April 27, where most residents opposed the clean-up proposal for Lake Bomoseen. A Facebook group called “Don’t Poison Lake Bomoseen” also led a protest in March, with concerns about the long-term health effects on humans and the health of fish and wildlife.

The Lake Bomoseen Association and the Lake Bomoseen Preservation Trust submitted the controversial permit to the Department of Environmental Conservation in February to use an herbicide called ProcellaCOR. The 325-page permit, provided by Solitude Lake Management, said Lake Bomoseen, the state’s largest landlocked lake, has had a milfoil problem since 1982. Milfoil currently covers about 30% of the lake and treatment efforts have been unsuccessful.

ProcellaCOR is the brand name for florpyrauxifen-benzyl, a plant hormone that regulates the development, growth and other functions of plants. The permit calls for injecting up to 123 gallons of it in the lake per year over three years, followed by long-term annual maintenance.

The associations said in the permit they’ve have tried lowering the lake levels during the winter to allow freezing of some sections for milfoil control, as well as mechanical harvesting, and diver-assisted suction harvesting (DASH), where scuba divers pull the weeds by the roots, among other mitigation efforts.

The permit is still waiting approval from the Dept. of Environmental Conservation (DEC). Oliver Pierson, the program manager of the lakes and ponds program at the DEC, said he’s heard “extensive feedback” about the permit.

Pierson said some people opposed the permit before it was filed. He’s received about two dozen phone calls and emails in opposition. Some residents even met with state officials in Montpelier, urging the state to reject the permit.

“The majority of what we’re hearing from the public is opposition to this permit application,” Pierson said, explaining some people are concerned about negative impact on fisheries. Some have health concerns about the impacts of putting a chemical into their waters.

Unlike other chemicals that are sprayed in the air, ProcellaCOR is injected below the surface of the water through the back of the boat. ProcellaCOR has been used in the state for the past three years and is now used on 13 different lakes. So far, all permits to use the herbicide have been approved.

“It’s relatively new,” Pierson said. “The state has not yet denied any applications, largely because the chemical does have a focused impact on the target species.”

Though the opposition is strong, Pierson said the state completed a study about the use of ProcellaCOR in April using data from 11 lakes, including Lake Hortonia, Lake St. Catherine and Lake Dunmore. The findings showed ProcellaCOR has almost no impact on plant life other than milfoil.

Pierson said there is no data on ProcellaCOR’s impact on fish, but there is anecdotal evidence that the herbicide has a negative impact.

“A lot of anglers in Lake St. Catherine that the bass aren’t as large as they were,” Pierson said. “We don’t have any data that would confirm that.”

Pierson said the Lake Bomoseen permit is the largest the state’s received so far. It calls for treating about 200 acres of the lake per year over three years.

“That’s by far the largest proposed treatment area of any application,” he said.

Pierson expects the state will make a draft permit to either accept the project or reject it by the end of June.

He said the state reviews a number of criteria before accepting a permit, one of which is public good.

“The perspective of these abutting towns is important,” Pierson said. “That will factor into our public good.”

The state will also likely hold a public informational meeting if a draft permit is granted. Meanwhile, the Rutland B.A.S.S. Club, Vermont’s largest Bassmaster-affiliated bass fishing club, is discussing legal action.

Erik Rasmussen, the president of the club, sent a letter to the Lake Bomoseen Association and state leaders on May 3, urging them to withdraw the permit. Rasmusseen said he was concerned about the loss of fish.

“They keep saying (milfoil) is an invasive weed,” he said. “Why is that a problem? They haven’t answered that.” He said ProcellaCOR has killed fish food and hiding areas in Lake St. Catherine.

“Within three years, the quality of fish in the lake is dramatically changed,” he said. “We’re stewards of the lake. It’s not the right thing to do.”