The August meeting of the Hudson Conservation Commission included a detailed update on the town’s ongoing invasive species control efforts at Robinson Pond and Ottarnic Pond. The work is part of a multi-year strategy to manage nuisance vegetation and improve overall pond health, with SOLitude Lake Management overseeing the latest rounds of herbicide treatment.
Chair Carl Murphy reviewed the timeline of this year’s work, noting that SOLitude conducted its first herbicide application on May 19, 2026.
Staff monitored the area throughout the treatment period for spotted turtles, a species of concern, but none were observed. A second treatment followed on June 7, targeting remaining invasive vegetation, and a third application was completed on June 23. Murphy said all treatments were limited to exterior areas of the ponds where invasive species were present.
Robinson Pond received additional treatment on July 7, primarily to address invasive milfoil, with a second round scheduled for August 12. Part of the cost is reimbursed through the New Hampshire Department of Environmental Services (NHDES), which partners with municipalities on aquatic invasive control.
Commission members asked about the monitoring requirements for spotted turtles. Alternate Makaela Murray questioned whether the monitoring was due to potential harm from the chemicals or because the species is protected. Vice Chair Ken Dickinson said the herbicides used are considered safe when applied correctly.
“They do tell the public that they can’t use the pond for about 48 hours after treatment,” Dickinson said. “There’s an initial shock there, but from what I’ve been told by the company, the halflife of the chemical is really quick. That’s part of the reason it’s so expensive – it targets the invasives and nothing else. It’s supposed to be pretty harmless to any aquatic species, including fish.”
Selectman Liaison Dillon Dumont added that NHDES regulations require monitoring during the turtles’ breeding season, which runs roughly from midMay to mid-October.
“During that time, any construction activities or chemicals like this need somebody to monitor the area to make sure the turtles aren’t being disturbed,” Dumont said. “If you do see them, there are other actions that need to be taken, so it might just be due to the timeframe when this is going on.”
Commission members noted that invasive species treatment is only one part of the town’s broader effort to maintain pond health. Dickinson said conditions at both Robinson and Ottarnic appear improved compared to last year.
“It would be good to go out there and see how things are going,” he said. “I’ve swam in Robinson Pond and it seemed to be in good shape; I swam in it several times this year. I’ve also been down to the boat launch at Ottarnic and saw that it’s been busy with people fishing and putting their craft out. I haven’t seen any bad activity. Maybe the best thing was that I didn’t see any algae blooms like were so prevalent last year. That was a big outbreak.”
The Commission plans to continue monitoring both ponds as the season progresses.
The next meeting of the Conservation Commission is scheduled for Monday, Sept. 14, at 7 p.m. in the Buxton Room at Town Hall.