Improvements in other aspects of the biology of switchgrass to enable it to grow effectively in more places, including current marginal lands, while utilizing even fewer inputs, will be important to meet lignocellulosic biofuel mandates. In many of these cases, the likely candidate traits for improvement are already noteworthy in switchgrass, many of them are correlated with invasiveness (Raghu et al. 2006); attaining improvements while minimizing invasion risk will prove challenging, but should be addressed. In addition, most trait improvements would carry environmental repercussions that have historically been difficult to convert to monetary value (Chamberlain
and Miller 2012). This includes improvements in carbon sequestration and N loss minimization (see Garten 2012), and water-use efficiency, all of which may be critical in "climate proofing" switchgrass for future conditions. How improvement in these traits will affect landscape-scale water quantity and quality, and associated sediment and nutrient runoff (e. g., Wu et al. 2012) is still empirically unknown.

The widespread planting of agronomic fields in monocultures of switchgrass for bioenergy will increase the susceptibility of switchgrass to pests and diseases. While switchgrass’ candidacy as a bioenergy crop is due in part to the absence of historical mention of pest and disease problems (Wright and Turhollow 2010), it is not free from such pressures. In fact, insect, fungal, and viral pests have been documented to have negative effects on switchgrass growth and production (Crouch et al. 2009; Prasifka et al. 2010; Schrotenboer et al. 2011; Burd et al. 2012), and some of the pests may well have negative effects on neighboring row crops (Burd et al. 2012). How to effectively and sustainably control these pests will prove imperative (Thomson and Hoffmann 2011).