Over the past several years, managers across the basin have taken advantage of high Great Lakes water levels to successfully control Phragmites by cutting stems under water (‘cut-to-drown’ method). However, several questions remain to determine if these management actions are effective across a wide variety of conditions within the Great Lakes. For instance, managers are unsure how long rhizomes remain viable after cutting, what season is best for cutting, and whether emergent zones connected to drowned Phragmites can “save” drowned patches. USGS and USFWS have been addressing these management uncertainties through a series of controlled experiments and large-scale field studies.