Officials discuss DEEP pesticide application and pond algae at golf course

At the June 17 meeting, the commission reviewed a DEEP permit application for pesticide use affecting ponds and state forest areas and heard from Brian Johnson, the town’s golf course superintendent, about proposed treatments for algae, duckweed and invasive pondweeds.

Johnson described the targeted species as early leaf pondweed (an invasive) and filamentous algae. Commissioners flagged one active ingredient, flumioxazin, because Environmental Protection Agency materials note it breaks down into degradates (APF and THPA) that are highly mobile in water and persistent. "Which are highly mobile in the water and very persistent," a commissioner said when summarizing EPA concerns. The commissioner asked whether that raised a potential for groundwater contamination; Johnson responded the golf course plans to use very small amounts and that the irrigation system is part of the context.

Commissioners recommended several complementary or alternative management approaches. Suggestions included increasing buffer widths around ponds to reduce nutrient runoff, more frequent water testing (Johnson said the course participates in an Audubon sanctuary program and typically tests in spring), and low-chemical tactics such as barley straw bales, which one commissioner said can reduce algae and cost about $35 per bale. Other options discussed included alum (aluminum sulfate) and products like Fosloc to address phosphorus-driven plant growth. Johnson said the course does not use phosphorus fertilizers on turf and uses slow-release products for broader areas.

Johnson offered to obtain and share an EPA report and to ask the vendor for additional information on the degradates of concern. The commission did not record a formal vote on the DEEP application during the meeting; the transcript documents questions, technical advice and an offer by staff to send further reports to commissioners.