Agronomics of corn production under different crop rotations in New York

The 1996 Federal Agriculture Improvement and Reform Act decouples support p ayments from production. Consequently, grain producers must devise rotation s based on market prices. The objective of this study was to demonstrate to grain producers that soybean [Glycine max (L.) Merr.]-corn (Zea mays L.) o r soybean-wheat/red clover (Triticum aestivum L./Trifolium pratense L.)-cor n rotations under reduced inputs (banded herbicides plus cultivation, simil ar to 105 Ib N/acre) compared with continuous corn under full inputs (insec ticide, broadcast herbicides, similar to 140 Ib N/acre) maintains or enhanc es corn yields. Field-scale demonstrations, with participating farmers perf orming field operations, were established on four farms in New York in 1993 . When averaged across years and sites, the soybean-wheat/clover-corn and s oybean-corn rotations compared with continuous corn yielded 10% greater (14 1, 139, and 127 bu/acre, respectively). Grain yield, however, had site by r otation interactions. The soybean-wheaf/clover-corn rotation yielded greate r in eight of 12 site-year comparisons, and the soybean-corn rotation yield ed greater in seven site-year comparisons with continuous corn. Major produ ction challenges where corn did not respond positively to rotations include adequate stand establishment and weed control in the soybean-wheat/clover- corn rotation and adequate N fertility in the soybean-corn rotation. We suc cessfully demonstrated that soybean-wheat/clover-corn or soybean-corn rotat ions with reduced inputs compared with continuous corn under full inputs en hanced or maintained corn yield, New York growers, who adopt soybean-wheat/ clover-corn or soybean-corn rotations, have the opportunity to reduce corn inputs, thereby improving profitability and reducing potential environmenta l problems.