Large global corn and soybean stockpiles will limit upside for corn and soybean prices despite increasing drought conditions in Iowa and the western Corn Belt, grain market analyst Don Roose said at last week’s Iowa Farm Bureau Economic Summit in Ames.

"We’re stealing yield from the western Corn Belt, but not enough to make up for South America," said Roose, founder of U.S. Com­modities in West Des Moines. "Brazil and Argentina (corn) production is up 700 million bushels more than last year."

Corn has been stuck in a 25-cent trading range this summer despite predictions for a smaller than...