Scout for resistant weeds this fall
Researchers are encouraging farmers to scout for suspect herbicide-resistant weeds this fall.
Michigan State University’s Erin Hill tells Brownfield farmers should be looking for weed species that have survived earlier control measures.
“If it’s one species that is still alive and the other species that you tried to control did die back, that’s a good indicator that you may have resistance,” she explains. “If multiple species have survived an application that should be effective, that’s sometimes an indicator that something else has happened.”
Hill screens weeds in her lab by growing suspect seeds submitted by farmers and testing them against several herbicides. The process can be free for Michigan soybean growers depending on the sample.
“All the pigweed species, common and giant ragweed, lambsquarters, and marestail—those are the ones that we typically see,” she says. “But, over the last several years we’ve had inquiries about other species like grass species.”
She says scouting in the fall also helps farmers prepare for what weeds could be problematic the following season.