The latest effort to foil further growth of milfoil on a pond in Litchfield, Maine, has taken the form of layers of black, geotextile mats.
A diver has placed the mats like carpet on the bottom of Upper Pleasant Pond in an area where a group of variable-leaf water milfoil plants was already marked off by buoys. The mats are made of a geotextile fabric and are held down by reinforcing rods that are placed into sleeves.
Plants under the mat die from lack of sunlight and slits in the fabric allow gases from decay to escape to the surface.
The plan is to also install mats near a public boat landing this spring to other sites if they prove successful.