Diversity key to weed-management plans
Pat Sullivan has what he calls a “pretty simple plan” when it comes to weed control on his south-central-Minnesota farm. It may be simple, but it’s exactly what many scientists promote as the way to prevent herbicide resistance.
“We use a pre-emerge herbicide on all our soybean and corn ground, then come back in post-emergence with different concoctions, using different products,” Sullivan says. He’s careful to use different modes of action in spraying early while weeds are still small, before they become more difficult to kill.
His plan also involves paying attention to detail and doing things many other farmers aren’t. That includes hand pulling troublesome giant ragweed and waterhemp from fields and every fence line, hand spraying some areas and completely mowing road ditches twice a year to prevent weeds in those uncontrolled areas from going to seed.
These different practices are the essence of the diverse weed-management plans being promoted as a way to fight resistance. That diversity can come in many forms, including:
- Herbicide site of action
- Herbicide chemistry
- Pre-emergent herbicides
- Post-emergent herbicides
- Tillage practices
- Row spacing
- Crop rotation
- Cover crops
“We even pulled the cultivator out and cultivated around the edge of every soybean field,” Sullivan adds.
Sullivan says it takes a lot of time and effort to go the extra mile for weed control, and he’s not always popular when he tells his children and employees they’re going to go pull weeds that day. But the alternative is much worse.
“It’s going to be a huge problem if we don’t kill these weeds,” says.
Having a diverse weed-management plan is an important tool farmers can use to keep resistance at bay.
“Farmers need to have a diverse approach that deals with the weeds they have and the tillage system that works for them,” adds Mark Loux, weed scientist at Ohio State University. “They need a strategy that fits their weeds and utilizes herbicide diversity.”
Find some of those tools on the Take Action website, and start developing your own weed management plan.