Nitrogen and Phosphorus Fertilizer Effects on Establishment of Giant Miscanthus

Research efforts have recently been increasing to evaluate giant miscanthus (Miscanthus x giganteus L.) as a bioenergy feedstock and to develop recommendations for efficient management practices. The objectives of this study were to evaluate effects of nitrogen (N) and phosphorus (P) fertilization on the yield and nutrient removal of giant miscanthus and the change in soil nutrient concentration during establishment of giant miscanthus in the Piedmont and Mountain Regions of North Carolina. Research sites were established at Mills River and Oxford, NC, in 2008 and 2009, respectively. Yield and tissue nutrient content were determined after senescence. Giant miscanthus produced biomass dry yields of up to 24 Mg ha(-1) during the third growing season. Fertilization with 45 kg N ha(-1) increased yield by 46 % in 2010 at Oxford, but did not affect yield at Oxford in 2009 or at Mills River from 2008 to 2010. Fertilization with 147 kg P ha(-1) increased yield by 32 % in 2008 at Mills River, but did not affect yield in 2009 or 2010 at either site. Mehlich-3 P concentration in the upper 20 cm of soil decreased after initial P applications, with no changes in the 0 P control plots detected during this study. Giant miscanthus successfully established at Mills River and Oxford, NC with minimal N and P fertilizer inputs on soils with low initial P concentration.