The corn leaf aphid, Rhopalosiphum maidis, is an important part of fresh market sweet corn in New York. Heavy infestations can reduce yield, and adversely affect ear quality through their presence, honeydew, and sooty mold contamination. In 1998, we conducted studies to investigate the important natural enemies of corn leaf aphid, the relationship between planting date and crop phenology and corn leaf aphid infestations, and we evaluated sweet corn breeding lines for potential resistance to corn leaf aphid.