The non-native invasive species, water chestnuts, have been spotted in Lake Saint Catherine in Poultney and property owners are now watching for more of the plants.
Earlier this summer a contractor found them while conducting a plant survey. The contractor was treating the pond with an herbicide to control Eurasian milfoil, another nonnative invasive species.
Like milfoil, water chestnuts can choke out native plants in the lake.
Jim Canders of the Lake Saint Catherine Association says the chestnut seeds could have been brought to the lake by waterfowl.