Variable Milfoil is present in 75 locations in NH including Ossipee, Squam and Winnipesaukee lakes. We should be hyper-vigilant to the possible introduction of this plant to Conway Lake.
Variable Milfoil (Myriophyllum heterophyllum) has a very stiff and thick stem and is more robust than the other milfoil species. The leaves are in whorls of 4 to 6 and can grow up to 2 inches long. Leaves on upper stem are whorled, and may be whorled or alternate on lower stem. Variable water-milfoil can grow to 15 feet in length. In July, flowers emerge from the water and are in a spike up to 6 inches tall with distinctive oval-shaped, toothed bracts. Can also form a succulent amphibious form when water levels recede. (Excerpted from Aquatic Plants & Algae of New Hampshire’s Lakes and Ponds).
Photo from "Maine Field Guide to Invasive Aquatic Plants"
Invasive milfoil collected by diver Cliff Cabral
Invasive milfoil collected by diver Cliff Cabral