| Summary: | Accelerated residue degradation and nutrient cycling will be necessary to maximize yield potential in corn (<i>Zea mays</i> L.) grown continuously and in other high-volume residue situations. This study aimed to test if residue management and agronomic inputs could lessen the continuous corn yield penalty (CCYP) compared to a corn following soybean [<i>Glycine max</i> (L.) Merr.] rotation. Field experiments conducted during 2017 and 2018 at Champaign, IL, USA compared plots of 15th year continuous corn to long-term corn-soybean rotation plots. The previous year’s corn crop residue was either downsized (chopped) or harvested with standard knife rollers, with further chemical management of either a biocatalyst or ammonium sulfate, or it was left untreated. A standard management system of 79,000 plants ha<sup>−1</sup> and a base rate of nitrogen fertilizer was compared to an intensive management system of 111,000 plants ha<sup>−1 </sup>with additional fertilizer and a foliar fungicide. Although continuous corn cropping stress was not detected until R2 (kernel blister stage), the CCYP was 1.30 Mg ha<sup>−1</sup>. Sizing residue enhanced overwinter residue decomposition and increased yield by 0.31 Mg ha<sup>−1</sup> regardless of rotation and by 0.53 Mg ha<sup>−1</sup> in continuous corn. Intensive inputs in combination with residue sizing increased grain yield of continuous corn by 1.15 Mg ha<sup>−1</sup> over standard-management rotated yields. Therefore, combining mechanical and agronomic managements can reduce corn residue and the CCYP for more sustainable crop production.
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