Nitrogen affecting switchgrass yield, nitrogen removal, and use efficiency

Abstract

Best management practices for switchgrass (Panicum virgatum L.) fertilization in the production of biofuel feedstock and forage hay are variable depending on climate, harvest timing, and variety. A study of N fertilization was conducted to evaluate the yield response, nutrient removal, and nitrogen use efficiency (NUE) in 12 yr old switchgrass stands in Stillwater, OK. Seven rates of N fertilizer were applied ranging from 0 to 235.2 kg N ha−1 for 3 consecutive years (2008, 2009, and 2010). Positive linear trends in yield with increasing rates of N fertilizer (P