Starting early is the key to effective weed control in peanuts.

“If you get behind, you're behind all year,” says Chad Godsey, Oklahoma State University Extension peanut specialist.

Godsey, speaking at the recent Oklahoma Peanut Expo in Lone Wolf, said growers should begin with an effective burndown treatment before they plant, use a good preplant herbicide and follow up with a pre-emergence application and a post-emergence treatment as needed.

“Be ready to get the first flush of weeds,” Godsey said. “Be active about control. Labels say target small weeds.”

He said tillage and seedbed preparation are important. “An effective burndown material is particularly important on strip-till or no-till plantings.” He said more growers are looking at reduced-till options to reduce trips across fields and to lower energy costs.

“With a burndown, we want to eliminate all weeds in the field before we plant,” he said. “At-cracking or post-emergence, treatments should go on as soon as you see weeds developing. Growers can't skimp on weed control even though some of the best programs are the most expensive.”

He said Valor worked well last year, but he advised growers to apply it before cracking time. “If you see any cracking, don't use it.”

Godsey said sprayer calibration, tip selection and droplet size also merit attention. “Droplet size is extremely important to limit spray drift,” he said. “Smaller droplets provide better coverage, but also are more likely to drift. Reducing droplet size by half means 8 times more droplets.”

He recommends peanut farmers use a field-specific approach to weed control. “Tailor control to a particular weed spectrum. Be aggressive and proactive.”

Godsey also said farmers must be aware of potential herbicide resistant weeds. “We have not seen resistance to yellow herbicides.” Possible reasons for occasional efficacy lapses could be weather related, he said.

“Last year we were very wet and I was amazed at how well the yellow herbicides worked. It made me wonder if they have not been as effective during some of the dry years we've had.”

He said some growers also may not be incorporating pre-plant incorporated herbicides deeply enough. He also said that irrigating to incorporate in no-till situations may not get the material as deep into the soil as tillage does.