Any reports of Round-Up resistant weeds in Michigan? Three have been found in Ohio.
The problem especially has been devastating in the southern United States, where Roundup-resistant pigweed is choking out cotton. Ohio’s problems are more manageable, experts say, but the state has three resistant species — marestail and giant and common ragweed — infesting corn and soybean fields. Southwest Ohio is the hardest hit part of the state, but the weeds are spreading eastward.
The article linked above provides some discussion on the use of Round-Up ready crops vs. the former practice of heavier tillage work and harsher chemicals. Quite a dilemma.