Farmers Matt Wiggeim, right, and Cody Gibson mix Monsanto Co.'s Roundup herbicide near a corn field in Kasbeer, Illinois, U.S., on Monday, June 13, 2011. Corn fell to a one-month low and soybeans declined on speculation that favorable weather will boost yields in the U.S., the world's biggest grower and exporter. Photographer: Daniel Acker/Bloomberg via Getty Images
