ASHFIELD — With Selectboard approval, a study examining the best methods to remove invasive vegetation on the Ashfield Lake Dam is set to begin in the spring.
The study, funded by a $25,000 grant from the Woodlands Partnership of Northwest Massachusetts, will test the effectiveness of herbicides, smothering and a mix of mechanical methods, including hand pulling and burning, to remove a buildup of vegetation on the riprap of the dam. The riprap is a layer of large stones on the slope of the dam that protects it from erosion.
Dam Keeper Ron Coler said the study will specifically be looking at the best ways to remove the buildup of Asiatic bittersweet and Virginia creeper on the dam, as well as any other vegetation that could get in the way of maintenance and upkeep.
“Anything that could compromise either being able to see the riprap or could affect the structure of the riprap,” Coler said.
Coler told the Selectboard that the study was designed by Tighe & Bond, and will include three test plots surrounding the spillway, as well as a fourth control plot. The plots will be approximately 40 square feet.
He added that the study proposal was reviewed and approved by the Conservation Commission. Coler said he will continue working with the commission and keep members notified when herbicides are being used.
“I spent the better part of the year on the phone with ConCom, and I’ve got an order of conditions, and I have obligations with that order of conditions to get certificates of compliance,” Coler said. “This thing is very closely monitored.”
Application of herbicides will be conducted by a licensed vegetation management vendor, Coler said. Procurement of a vendor will occur this winter.
Treatment of the test plots will begin in May and the study will last through October. Analysis of the study will be completed in November and December of 2026.
Tighe & Bond is estimating the herbicide treatment will cost $3,000, the smothering treatment will cost $2,500 and the mechanical treatments will cost $500. Tighe & Bond will charge the town $16,200 for managing the study.
The Selectboard approved the contract with Tighe & Bond, allowing Coler and the company to proceed with procuring a vegetation manager.