Nitrogen fertilization rate and swine effluent application effects on bioenergy sorghum production in North Carolina

Dry matter yield and nutrient removal information is critical for the development of nutrient management plans to optimize productivity and environmental conservation goals. Sorghum cultivars ES5200 and M81-E were evaluated for four years in North Carolina in experimental areas located at a research station and also on-farm. Dry matter yield of sorghum ES5200 was greatest at a N fertilization rate of 67 kg per hectare with no significant increase of dry matter yield production beyond this N rate.  There was no N fertilization rate effects for dry matter yield response of sorghum M81-E. Both sorghum cultivars were productive biomass crops at swine spray fields and may be a feasible alternative for producers that desire the flexibility of an annual crop and high biomass yields (~16 Mg per hectare) in a single clipping at the end of the growing season; however, nutrient loadings will need to be less intensive (lower amounts) compared to current bermudagrass-based systems to comply with NC nutrient management plan guidelines.

Publications: Agron. J. 109:1352-1358; Agron. J: 109:2521-2529; CSANews; Agron J, doi:11.2134/agronj2018.0..0178