Evaluating the spread and control of Eurasian watermilfoil through remote sensing technologies

Eurasian watermilfoil, Myriophyllum spicatum, (EWM) is a non-native aquatic plant first documented in the U.S. in the 1940s and now present in all of the Great Lakes. It can crowd out native plants, hybridizes with native milfoil, and can be a nuisance to recreation. Extensive control efforts often provide only short-term relief. Projects funded through the U.S. EPA Great Lakes Restoration Initiative (GLRI) and the Michigan DNR have enabled a Michigan Tech team to demonstrate methods to help arrest the spread of EWM and evaluate the effectiveness of multifaceted control measures. These projects include applying remote sensing technologies to help understand the locations and spread of EWM, and to assess the effectiveness of control efforts. Imagery collected using satellite and unmanned aerial vehicle (UAV) platforms have been used to create classifications of cover types to map the locations of EWM in northern Great Lakes study areas. Spectral profiles of EWM and other macrophytes have been collected to create unique signatures to aid in mapping, with EWM appearing distinct in the 500-650 nm (green to red) wavelengths. Approaches to practical application include collecting data over larger areas with a UAV, completing development of a EWM spectral algorithm, and monitoring a site undergoing treatment for EWM