Harvest is in full swing across the country, and farmers in many states are surprised at the abundance of corn they’re getting from their fields. Dairy farmer Ben Steffen, who also grows corn, soybeans and wheat on 1,900 acres near the southeastern Nebraska town of Humboldt, said his first corn field brought in 168 bushels an acre, above the average of 140. … The best crops in the U.S. are in areas that received adequate rain combined with cooler temperatures at the time corn pollinated, a welcome sight after last year’s dismal harvest due to the drought withering corn and...