A Milfoil Eradication Success Story
In 2012, scientists from Restorative Lake Sciences studied Long Lake in Iosco County, MI and found that the 493-acre natural lake with 8.1 miles of shoreline was infested with dense quantities of native aquatic plants and exotic aquatic plant growth.
The overall mean depth of the lake is approximately 16.8 feet which is deep; however, the majority of the littoral (shallow) zone of the lake is vegetated. In addition to the abundant native aquatic plant species, there is was overabundance of the invasive species Eurasian Watermilfoil (Myriophyllum spicatum L.). Due to the abundance of Eurasian Watermilfoil in the lake, the primary mode of aquatic plant control could not include mechanical harvesting due to the inherent high risk of fragmentation. Additionally, the use of the aquatic weevil, Euhrychiopsis lecontei to control Eurasian Watermilfoil had proven to be ineffective or minimally effective throughout Long Lake despite having stocked over 209,000 weevils between 2009-2011. Furthermore, a lake drawdown would not have yielded enough water loss due to the small size of the dam and impacts of drawdown on Eurasian Watermilfoil are unpredictable.
Thus, the ultimate solution for the control of approximately 296 acres of Eurasian Watermilfoil in Long Lake consisted of the application of the systemic herbicide Triclopyr (Navitrol®) near shore with chelated copper (Cutrine®) and granular 2,4-D (Navigate®) and Cutrine offshore in mid-June of 2013. By late August, all of the milfoil was gone and an eradication was noted. The residents are proud to have their lake restored and the native biodiversity of aquatic plants in Long Lake is now protected.