Washington, D.C. [DesMoinesRegister.com]Farmers saw high prices for corn this spring and planted even more than expected. That may help hold down food prices, but it’s bad news for struggling biodiesel makers who depend on soybean oil. The U.S. Department of Agriculture reported Friday that farmers nationwide planted 92.9 million acres of corn this year – 19 percent more than last year and 3 percent more than the government had projected in March. The demand for ethanol led U.S. farmers to plant the most corn since 1944. But that extra corn acreage means that farmers planted 15 percent less land to soybeans.