Farmers find success in overlapping residual corn herbicides

Managing herbicide-resistant weeds is a growing concern across the Midwest, and farmers are realizing that incorporating multiple modes of action is no longer an option, it is a necessity.

"Weed resistance is real," said Gordon Vail, Ph.D., technical product lead for Syngenta. "For farmers, it is no longer a question of if, but when resistant weeds will make their way into their fields."

With weeds such as waterhemp, lambsquarters and ragweed becoming harder to control with glyphosate and other single-mode-of-action herbicides, farmers are overlapping pre-emergence and post-emergence residual herbicides for maximum control.

"A lot of companies claim their products have multiple modes of action. But if one mode of action is an ALS inhibitor and you have ALS-resistant weeds, that means a two-mode-of-action product essentially only has one mode of action that works against that weed," Vail said.

He continues, "These are the types of things we're trying to teach our customers. When you're considering a herbicide, it's important to think, 'What components in this product are actually controlling the weeds I have at the time I'm spraying them?'"

Dave Keffeler, who farms in Remson, Iowa, said he made some tweaks to his weed management program after experiencing trouble controlling waterhemp and lambsquarters with glyphosate alone. "That's a big reason why we went to Lexar herbicide followed by Halex GT herbicide plus atrazine," Keffeler said. "Now, we have a program that gives us four modes of action for 100 percent control."

Farmers in Illinois are incorporating similar weed management strategies. "Our biggest weed pressures are lambsquarters, velvetleaf, and giant ragweed, but giant ragweed seems to be public enemy number one," said Jeff Becker, who farms in Stephenson County, Ill.

"It's very important to start clean, so our first pass is Lexar, which provides residual control until we come back with Callisto Xtra herbicide. Lexar has three different modes of action and Callisto Xtra has two, which helps manage against weed resistance, plus delivers season-long control," he said.

For the 2013 season, farmers who have relied on Lexar and Lumax herbicides for their consistent performance, long-lasting residual control, application flexibility up to 12-inch corn and proven crop safety will get an added benefit - an enhanced formulation designed for improved handling.

"Whether a farmer or a retailer applies new Lexar EZ and Lumax EZ, they are really going to like the new formulation," said Bob Kacvinsky, agronomy service representative for Syngenta. "Those who have used these products in trials have been very impressed."

Lexar EZ and Lumax EZ are based on the same capsule-suspension technology as Halex GT, which has risen in popularity to become the number one glyphosate premix in corn.

"Halex GT is just a fantastic product because it combines the burndown of glyphosate (Touchdown herbicide) with the residual of Callisto and Dual Magnum herbicides," Vail said. "In market research studies, nine out of ten farmers1 who try Halex GT use it again the next season, which is a strong testament to its proven, consistent performance."

Farmers across the Midwest say they use Halex GT because, quite simply, "it works."

"With Halex GT, you have three modes of action - three ways to control that weed," said Nick Schmit, who farms in Coleridge, Neb. "It keeps your field clean and keeps the product sustainable for future use. It works. It's as simple as that."

By combining glyphosate with residual, an early post-emergence application of Halex GT helps keep fields clean from spike to crop canopy.

"Halex GT provides great control through a wide range of conditions during the year," said Bill Markel, a grower in Sidell, Ill. "We have a lot of waterhemp, grass pressure and giant ragweed. The residual control is excellent and my fields stay clean all the way through harvest."