Soybeans are sprayed in Iowa in 2013. Enlist Duo is a mixture of two chemicals that farmers have used separately for many years: glyphosate (also known as Roundup) and 2,4-D. The new formulation is intended to work hand-in-hand with a new generation of corn and soybean seeds that are genetically engineered to tolerate sprays of both herbicides.
Sunlight streams into a corn storage building at a Michlig Grain storage facility in Sheffield, Illinois, U.S., on Oct. 31, 2014. The price of corn has been falling for months.
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