New Herbicide Available

Warrant now labeled for use in peanuts; early postemergence application recommended.

Peanut growers looking to control their fields’ toughest weeds – including Palmer pigweed, waterhemp, lambsquarters, giant foxtail and nightshade, among other small-seeded broadleaf weeds and grasses – have yet another tool for the 2014 growing season. The Environmental Protection Agency (EPA) recently approved Warrant herbicide for use in peanuts. Warrant is an encapsulated acetochlor, first introduced by Monsanto in 2010, that has been used on millions of acres to control weeds in cotton, soybeans and grain sorghum. “Growers have been asking us to pursue expanding the Warrant label to include peanuts,” says Austin Horn, Monsanto’s marketing manager for selective herbicides, “And now, they’ll have access to this tool in most peanut-growing states where acetochlor is currently labeled, including Alabama, Arkansas, Georgia, Mississippi, North Carolina, South Carolina, Oklahoma and Texas.”

Residual Activity
Horn emphasizes the importance of using multiple modes of actions in a weed management program. “Applying residuals is imperative for effective weed control, and Warrant provides enhanced residual activity for weed resistance management,” he says.

Warrant is labeled for pre-emergence and postemergence applications, but Horn says the pre-emergence timing is not recommended because of the potential for crop injury. Instead, Monsanto recommends application from postemergence through flowering. The rate is 1.25 to two quarts per acre per application, not exceeding four quarts in a season.

Early Post Timing
Eric Prostko, University of Georgia Extension weed specialist, says that Warrant received both the federal label in January and approval for use in the state of Georgia in February. “The current supplemental label only permits pre-emergence and/or early postemergence applications before flowering,” Prostko says. “Of these two timings, I would prefer to see the early postemergence applications of Warrant tankmixed with Gramoxone + Storm + a non-ionic surfactant (NIS).”

Practice Resistance Management
Prostko says he has not observed any real differences in weed control between Dual Magnum and Warrant based on peanut weed control programs, but some cotton data suggests that Warrant might be a better choice for non-irrigated fields. Prostko also wants producers to know that Warrant is not Lasso. “Although they are different compounds, Warrant, Lasso and Dual Magnum are in the same herbicide family.” For more information on Warrant herbicide, producers can contact their retailer or visit RoundupReadyPLUS.com and click “Products.”