Building a Maximum Yield Cropping System for Corn, Wheat and Double-cropped Soybeans

The goal of this study is to develop a management program that increases crop yield, input efficiency, and profit potential in a predominantly no-till cropping system. This cropping system consists of four crops in 3 years: no-till soybeans in corn stubble, followed by minimum-till wheat double-cropped with no-till soybeans, and then no-till corn.

The rotation clearly improved corn and soybean yields compared to continuous cropping. Starting in 2000, nitrogen (N) use efficiency has appeared to improve when ammonium sulfate (AS) was blended into the N source, either urea or ammonium nitrate. In 2003, in no-till and strip-till corn with AS supplying one-third of the N, corn yield increased by 30 bu/A, particularly with split application, compared to broadcast urea. In experiments comparing starter and broadcast fertilizers, AS and phosphorus (P) appeared to be the ingredients associated with the highest corn yields, despite high soil test P. MD-06F