Georgia Growers Lay the Blueprint for Pigweed Control

Georgia Growers Lay the Blueprint for Pigweed Control

From Cotton Grower Magazine – December 2014



Like many growers across the Cotton Belt, Dwain Parrish sees additional acreage as one of the few safeguards against freefalling cotton prices. As a result, he often rents new cotton ground to add to his roughly 1,500-acre farming operation near Fitzgerald, GA.

Unfortunately, in a region that is widely considered Ground Zero for glyphosate-resistant Palmer amaranth, each patch of ground has a history with the weed pest.

“We’ve had a lot of weed pressure in the last few years, especially on the land that we’ve taken into the operation,” Parrish says. “We’ve inherited some problems, for sure.”

But Parrish is hardly unique among cotton producers in Georgia. Resistant weeds have left a mark across the state since they were first officially confirmed in 2005.

What is noteworthy, however, is the workman-like attitude he displays when talking about dealing with pigweed in his fields. It’s difficult to find the time or the labor for a chopping crew, so he utilizes a proactive herbicide program with a Liberty-tolerant variety, Stoneville ST 6448GLB2.

“This year we’ve used Prowl H20, and then at planting time we were using – behind the press wheel – another application of Prowl H20 and then Agriliance’s version of Reflex,” Parrish says. “Then we use Warrant in combination with the Liberty over the top, and then come back with a layby application usually of Roundup and Valor just to get any escapes.”

Parrish’s aggressive herbicide program is one of many examples of a changing weed landscape in Georgia. Suddenly, agriculture professionals there are using different terms when talking about the battle against resistant weeds. In 2014, more fields were clean and more growers were declaring victory over a weed pest that once ravaged the agriculture community.

The end result? Clean fields and subsequently stronger yields.

“I’ve been really pleased, especially with the yields on the ST 6448GLB2,” Parrish says. “This year, on my irrigated ground with that variety, my yields have been averaging between 1,600 pounds and 1,900 pounds an acre.”

The herbicide program Parrish uses isn’t cheap, but it works. Like most growers in the state, he understands it’s ultimately cost effective to stamp out resistant weeds before they become problematic in his fields. And that message is catching on across the Cotton Belt.

From Georgia to California, American cotton producers have accepted the fact that there are no shortcuts when it comes to the resistant pigweed issue. That’s why, as University of Georgia Extension weed specialist Stanley Culpepper reports, American producers have invested over $1 billion in the past decade to stop glyphosate-resistant Palmer amaranth.

It makes sense for Georgia – the first state to confirm glyphosate resistant pigweed – to be one of the first places for that investment to begin visibly paying off.

Seeing it Through

Brandon Phillips moved to the Peach State in 2000, just in time to witness the beginning of the glyphosate resistant epidemic. From the beginning, he set about consulting farmers in and around Ben Hill and Irwin Counties.

“Actually, in 2006, Ben Hill County was one of the first counties in the state of Georgia to confirm pigweed resistance, and, of course, it was in one of the fields that we were checking,” Phillips says. “So yeah, we were pretty much at Ground Zero with it.”

Because he had a front row seat to the epidemic, Phillips has a unique perspective on the tactics growers in his state have used against the weed pest. In the beginning, growers had no idea how versatile and adaptive pigweed could be. Now, Phillips says, every precaution that can be taken is utilized – right down to thoroughly washing equipment in between field passes. But there were years where, despite everyone’s best efforts, pigweed ran rampant through the state.

“The toughest years were probably 2008, 2009, 2010 and 2011,” Phillips says. “Back in 2005 and 2006, it was just getting started in that timeframe. But we had four years where we tried everything under the sun and it just didn’t work out, and entire fields would be just eat up with pigweeds.”

Phillips credits a better understanding of the weed pest, as well as a better understanding of new chemistry like Liberty, for helping growers like Parrish – who is a client of Phillips Ag Services – to turn the corner against Palmer amaranth.

“It just took us a couple years to figure out the Liberty system, but here we are now,” Phillips says. “I think we’ve got it beat. We’re doing a better job now than we’ve ever done before, just in the last two or three years controlling pigweeds. That starts with keeping residual herbicides overlapped every 10 days during the growing period, starting at burndown.

“We know what it takes, we know what the input costs are, and we’ve figured those into our budgets. We’re going to have anywhere from $70, $80 to even $100 per acre in some scenarios of herbicide costs. But that’s what it’s going to take, and it’s worth it.”