pdf HL1: Management of Eurasian watermilfoil in Houghton Lake, Michigan: Workshop Summary

Management of Eurasian watermilfoil in Houghton Lake, Michigan: Workshop Summary


Authors: Kurt D. Getsinger, Angela G. Poovey, William F. James, R. Michael Stewart, Michael J. Grodowitz, Michael J. Maceina, and Raymond M. Newman

Author Affiliation: U.S. Army Engineer Research and Development Center

Journal: Aquatic Plant Control Research Program, ERDC/EL TR-02-24, September 2002

Abstract: Conventional mechanical control techniques could theoretically be used to control all actively growing milfoil beds in Houghton Lake. However, due to the acreage involved, the low areal production rates of these systems, and the regrowth of harvested milfoil plants in 4 to 6 weeks, treatment by this technique will probably be limited to small high-use areas (e.g., boat lanes, marinas, boat launches, etc.) and control of free-floating plant fragments in open water. Biological control techniques focused on the milfoil weevil, which is highly specific to watermilfoils. Chemical control techniques focused on both contact and systemic aquatic herbicides that were registered in the state of Michigan. With aquatic herbicides, species-selective control is important; the population of the invasive Eurasian watermilfoil can be significantly reduced while limiting negative impacts on the desirable native plant community. It is clear that actions can be undertaken to greatly reduce the amount of milfoil in the system, and keep milfoil populations at a reasonably low level, while restoring and conserving the recognized benefits of a diverse native aquatic plant community. In order to achieve such a goal, it is imperative that a lake management plan be developed to address the short-term problems associated with the infestation for the next 1 to 3 years, followed by addressing the long-term reduction and continued control of milfoil in Houghton Lake over the next several decades. This plan should prioritize the most valuable resources and lake uses in order to design and implement activities for restoring and maintaining Houghton Lake in a healthy condition now and in the future. Watershed management practices, including maintenance of shoreline property and lake level issues, should be reviewed and assessed to determine impacts of those processes on the implementation and success of milfoil control techniques applied to the lake.