Herbicide-resistant pigweeds are a rapidly-expanding threat to row-crop agriculture in the South. Researchers are hard at work trying to find the best way to regain control of burgeoning resistant populations.

At the recent PigPosium — a forum on resistant pigweeds held in Forrest City, Ark., and co-sponsored by The University of Arkansas Division of Agriculture and Delta Farm Press — attendees heard that wick applicators are one of the control methods being studied.

“We’re here for a very serious reason,” said Eric Prostko, University of Georgia professor and Extension weed specialist, to a packed house. Pointing to a picture of a row-crop field overtaken by pigweeds, Prostko said, “This summarizes things.”

According to Prostko, among Palmer amaranth control tactics: starting clean, tillage, extreme cover crops, residual herbicides, irrigation, post-harvest (corn), hand-weeding, and non-selective applicators (NSAs).

The list above summarizes much of the ongoing resistant weed research in the Southeast and Mid-South. “There may be some variations based on some things we’re doing in Georgia a bit differently. We’re one or two years ahead of you in our fight against this problem.

“At the very end, I list hand-weeding and non-selective applicators. I’ll refer to the applicators as non-selective because there are more than just wick applicators available. Regardless, we want growers to do everything possible before they get down to those last two options. Those are certainly something we’re not used to doing.”

NSA technology isn’t new, said Prostko, as an alarming picture of a trailer full of huge, freshly-cut pigweeds appeared on the screen. “It’s been around 30 years, although we’ve never really used it that much. This illustrates why (NSAs are now in the mix). This is where we are in Georgia, now. … But this isn’t sustainable in the long run. In some cases, our growers are spending a lot of money hand-weeding. So, they’re interested in any option other than this — including NSAs.”