Invasive Aquatic Plants

Variable Leaf Milfoil

Variable leaf milfoil is an aggressive invasive aquatic plant. It was found in 2014 at the boat launch in Annabessacook Lake. It is imperative to take quick action against variable milfoil because it spreads quickly, forms thick mats, and is highly difficult to eradicate once established. It has no natural predators to control its population, so only humans are capable of preventing its spread.



Eurasian Water Milfoil

Eurasian water milfoil is an invasive aquatic plant that has recently been spotted in the northern end of Cobbossee Lake. Due to its particularly aggressive nature, it is imperative that this outbreak be taken care of immediately. Much like variable leaf milfoil, eurasian water milfoil is highly difficult to eradicate once established.



European Frogbit

European frogbit is an aggressive invasive aquatic plant that has recently been spotted on the north end of Cobbossee Lake. European frogbit is a free-floating plant that has heart-shaped leaves. During the summer months, it produces a white flower with three petals and a yellow center. Like variable leaf milfoil, European frogbit forms thick mats as it grows, obstructing native plants from receiving sunlight. When it eventually dies and decomposes, the frogbit deprives nearby water of oxygen that fish need to survive.



Additional Resources: 

Milfoil Identification QuickKey

Invasive Plant Guide

Variable Milfoil Factsheet

Maine Department of Environmental Protection

Lakes Environmental Association

Lake Stewards of Maine

University of Maine Eurasian Milfoil Bulletin