Canada Thistle, identification of the Wisconsin Invasive Species Cirsium arvense 

This is part of a series of videos providing key characteristics for the identification of invasive plants listed in Wisconsin's invasive species administrative rule NR 40. These videos are produced by Dr. Mark Renz of the University of Wisconsin-Madison. For more information on invasive plants and invasive plant management in Wisconsin visit fyi.uwex.edu/we... or ipcm.wisc.edu/P...