Farmers in Iowa and around the country working to manage their cash flow are planning to plant more corn acres this spring and cut back on soybeans, the latest report from the U.S. Department of Agriculture (USDA) report showed. And if the forecast is correct, it’ll be the third largest planted corn acreage in the United States since 1944, the USDA says.

U.S. corn farmers are expected to plant 93.6 million acres to corn this year, up 6 percent from last year, the USDA said in its prospective plantings report last week. If realized, this would be the highest planted...