Bauman said prevention is much preferred to battling established resistant weed populations. “Farmers can employ preventive programs now or they can wait until they see resistance and then act.”

But, considering that one resistant waterhemp plant can shed more than 400,000 seeds, it doesn’t take many to “supply weed seeds for years to come. Also, farmers may get pollen from resistant weeds blowing in from nearby farms.”

Consequently, Baumann encourages farmers to “take a prophylactic approach and prevent resistance by using soil-applied herbicides and other products.”

He said those options don’t mean farmers have to spend a lot of money on early-season weed control. And the investment pays off in more ways than preventing resistant weed populations.

“Early-season weed control limits crop competition,” he said. “If for some reason a farmer can’t make a post-emergence treatment, he could be in trouble without an early-season herbicide program. That’s a killer for yield loss.”

He said remedial weed control technology has given producers a false sense of security. “You can kill weeds that are 10 inches tall, perhaps, but while you’re getting those 10-inch weeds, they’re picking your pocket every day.”

He said a yield drag can occur within the first two to eight weeks of crop growth. “That’s when we need a weed killer out there.”