The 2016 University of Illinois Plant Clinic herbicide resistance report has shown that glyphosate herbicide resistance and PPO Inhibitor herbicide resistance have both reached epic proportions across the Midwest of the United States.
2,000 waterhemp or palmer amaranth weed samples were received by the University of Illinois Plant Clinic from 10 states across the Midwest, amazingly 456 of the whole field sites showed Glyphosate Resistance - a total of 76.8% of the 593 sites.
Meanwhile, 62.5% of the weed samples on the whole field sites showed resistance to PPO inhibitor herbicides. Also, 49% of weeds on the whole field sites showed resistance to both PPO inhibitor herbicides and glyphosate herbicides.