Cover crops impact on energy and forage crops productivity in North Dakota

Forage crops have gained interest as potential source of lignocellulosic feedstock to produce ethanol. More focus is needed on developing cropping systems to improve productivity. This study was conducted to identify the agronomic potential of six different cover crops on five different annual biomass crops. Results indicated that forage pea (Pisum sativum L. cv. Arvika) N uptake was 126 kg N ha-1 and was able to fix approximately 60 kg of N ha-1 in only 60 days in the fall. Results across locations indicated that forage sorghum (Sorghum bicolor L. Moench cv. FS-5), and sweet sorghum (Sorghum bicolor L. Moench cv. Theis) had the highest biomass yields among the forage crops with 17.8 Mg ha-1 followed by sweet sorghum with 15.3 Mg ha-1, respectively. Therefore forage sorghum and sweet sorghum can be considered as the most productive biomass sources, specially combined with a legume cover crop seeded the previous fall.