Working together with local and state stakeholders, Barr developed an aquatic-plant management plan for controlling Eurasian watermilfoil in Beaver Dam Lake. This 1,169-acre lake had Eurasian-watermilfoil infestation rates as high as 75 percent throughout its littoral area (the area less than 25 feet in depth). Most herbicide-treatment programs use a single herbicide and dose throughout the lake. In complex systems such as Beaver Dam Lake, this approach fails to consider variables that influence how long the herbicide is in direct contact with the macrophyte: lake area, depth, flow, and mixing. Barr addressed this by dividing the lake into eight zones, each with its own treatment and dosing plan.
Herbicide treatments have eliminated the dense watermilfoil growths that caused problems for boaters. Between 2008-2018, the extent of Eurasian watermilfoil was reduced by about 160 acres, declining to 3 percent of the lake’s littoral area. Now that watermilfoil is present at very low levels in Beaver Dam Lake, relatively new management approaches are being used—diver-assisted suction harvesting (DASH) and new herbicides. Barr’s innovative approach has successfully addressed this serious AIS management problem. Annual aquatic-plant surveys have documented that the native-plant community has thrived throughout the management period.
Senior GIS Specialist