Monsanto is cutting the price on its Roundup brand agricultural herbicides. “We will be reducing the price of both Roundup PowerMax and Roundup WeatherMax by up to 50%, effective immediately,” says Matt Helms, marketing manager for Monsanto crop protection division.

Global supply and demand issues put glyphosate prices on a roller coaster ride recently, with prices falling dramatically from 2008 and 2009 price levels back down to 2006 and 2007 levels.

Monsanto says it has the capacity at its Luling, LA, plant to increase domestic production and made investments to increase mining capacity for glyphosate raw materials in southeastern Idaho.

While news of the announcement may be a good deal for producers, Chris Boerboom, extension weed scientist at the University of Wisconsin, says producers should continue to be aware that the use of preemergence herbicides in a corn and soybean rotation may still be necessary. “The addition of a preemergence herbicide has been shown to decrease early season weed pressure, which is especially valuable in fields when weather delays postemergence glyphosate applications,” he says. “And controlling early season competition protects yield.”

The price of glyphosate won’t matter if there are glyphosate-resistant biotypes in your field, says Aaron Hager, weed science extension specialist at the University of Illinois. “Certainly producers may look at spraying glyphosate twice instead of using a soil-residual herbicide,” he says. “But alternating chemistries is imperative, especially if glyphosate resistance is a concern.”

Joe Sandbrink, technology development manager for Monsanto crop protection division, encourages the use of residuals in tank mixes when needed. “Our Roundup Rewards program provides incentives to producers who use other chemistries in areas where multiple modes of action are necessary for weed control. That program will continue to be offered.”

Monsanto’s price cut isn’t likely to spill over into other weed-control chemistries. “We don’t expect current glyphosate prices to directly impact other chemistries, as the prices of these products did not spike like glyphosate,” says Scott Langkamp, head, herbicide brand management, Syngenta Crop Protection.