Cover Crop Species and Cultivars for Drill‐Interseeding in Mid‐Atlantic Corn and Soybean

CORE IDEAS: Annual ryegrass and orchardgrass performed similarly in field corn. Medium red clover was the most consistent legume species in field corn. No effect of annual ryegrass cultivar was observed in field corn. Annual ryegrass was the most consistent species in soybean. ABSTRACT: Drill‐interseeding is becoming a viable method for integrating cover crops in no‐till corn (Zea mays L.) production in the Mid‐Atlantic region. Development of best management practices for drill‐interseeding cover crops into no‐till grain crops requires greater understanding of cover crop performance at the species and cultivar level. Experiments were conducted at multiple Mid‐Atlantic locations (Maryland, Pennsylvania, New York) in two consecutive growing seasons (2013–2014, 2014–2015) to evaluate establishment and performance of drill‐interseeded: (i) grass and legume cover crop species (n = 8) and annual ryegrass [Lolium perenne L. spp. multiflorum (Lam.) Husnot] cultivars (n = 10) in field corn, and (ii) grass and legume cover crop species (n = 6) in soybean [Glycine max (L.) Merr]. Fall biomass production of drill‐interseeded cover crops was higher and less variable among locations in field corn than soybean. Annual ryegrass, orchardgrass (Dactylis glomerata L.), medium red clover (Trifolium pratense L.), and crimson clover (Trifolium incarntum L.) produced greater mean fall biomass than other species in field corn, but variable winter hardiness of crimson clover resulted in less spring biomass than alternative species. No differences were observed among annual ryegrass cultivars. Annual ryegrass, medium red clover, and crimson clover produced greater mean fall biomass than other species in soybean across locations. Our results highlight the viability of a narrow suite of cover crop species for interseeding in Mid‐Atlantic no‐till grain systems and point to the need for development of agronomic practices that facilitate greater niche complementarity between cover and cash crops.