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Agronomy Journa l • Volume 109, I s sue 4 • 2017 Interest in economical alternatives to fossil fuels has grown over the past several decades as a result of greater energy demand, the need to reduce reliance on fossil fuels, and documented increase of atmospheric CO2 (Longinelli et al., 2005). Sorghum is a C4 grass that has emerged as a potential dedicated bioenergy crop for both biomass and sugar yields (Rooney et al., 2007). Nevertheless, sorghum responses reported in the literature have been variable within and across studies due to cultivar, environment, and management practices (Erickson et al., 2011; Maw et al., 2017). Swine spray fi elds of eastern North Carolina are areas that may be planted to dedicated bioenergy crops. Annually, 8.8 million hogs are raised within the state, most of which are located in the Coastal Plains physiographic region (USDA-NASS, 2015). As of 2014, there were approximately 50,000 ha permitted for application of swine waste (NC-DWR, 2016). Currently, the majority of spray fi eld sites are dedicated to bermudagrass [Cynodon dactylon (L.) Pers.] hay production because of its potential as a long-term waste receiver crop (Burns et al., 1985). High nutrient removal and response to N and water application are desirable characteristics for spray fi elds crops (Burns et al., 1990). Sorghum has been proposed (Rooney et al., 2007) as a potential bioenergy crop; nevertheless, there is very little information on DM yield and nutrient removal potential to support its production in North Carolina and specifi cally North Carolina’s spray fi elds. Th is information is critical to the viability of sorghum as an alternative dedicated bioenergy crop and to assist in the development of nutrient management plans. Hao et al. (2014) reported that the optimum N rate for sorghum production in the Texas High Plains ranged from 148 to 183 kg ha–1 yr–1. In Florida, Erickson et al. (2012) reported nutrient requirements for sweet sorghum between 90 and 110 kg N ha–1 and Singh et al. (2012) reported an average N removal rate of 136 kg ha–1 yr–1. In Illinois, Maughan et al. (2012) reported biomass responses up to 224 kg N ha–1. Adams et al. (2015) reported a minimum level of 127 kg N ha–1 needed to achieve sweet sorghum biomass production of 19.7 Mg ha–1; and most recently in Missouri, Maw et al. (2017) reported DM yield plateaued at 18.5 Mg ha–1 for high biomass sorghum fertilized with 56 kg N ha–1 and with 104% Nitrogen Fertilization Effects on Yield and Nutrient Removal of Biomass and Sweet Sorghum