Waterhemp control and soybean injury will be used to rank the various weed control strategies in both LibertyLink GT27 and XtendFlex soybean. Since glyphosate- and multiple-resistant waterhemp is still a relatively new problem in Michigan, information from this research will be used to develop updated recommendations based on Michigan data for waterhemp control. This information will be incorporated into our current recommendations for control of herbicide-resistant waterhemp in soybean in our web-based factsheets and in the MSU Weed Control Guide for Field Crops (E0434). We will continue to hold meetings throughout the state to make Michigan soybean growers aware of the issues and the options for management of waterhemp. The awareness from our outreach efforts will continue to be important to identify and manage this troublesome weed.

On September 17, 2019, there was a field day held at this location where approximately 25 farmers and Ag retailers attended. We would like to thank MSPC and Paul Gross for hosting this field day. The information was valuable for farmers in this area to learn more about waterhemp management strategies. The results from these soybean trials were critical to updating the “Multiple-resistant Palmer amaranth and waterhemp in Michigan: Keys to management”, factsheet that is in the 2020 MSU Weed Control Guide for Field Crops and posted on www.MSUWeeds.com. Results from these trials have also been presented at several winter extension meetings. This research has been important to provide effective information to soybean growers to help manage this troublesome economically significant weed problem. It will also provide additional control strategies and herbicide options to aid in the management of a weed that has the ability to develop resistance to multiple-herbicide sites of action.