The cultivation of cellulosic substrates for the production of biofuels has stimulated interest in switchgrass as an energy feedstock. However, little research has been done with respect to the effects switchgrass production has on the soil microbial community. The structure and function of this community has substantial influence on the potential C dynamics of the soil during production, a component of the overall C “footprint” of this system. Thus, as part of a greater project examining all aspects of terrestrial C sequestration during switchgrass production, we identified four cultivars of switchgrass grown in research plots in Tennessee and sampled the soil in which it was grown. The cultivars were Alamo, Kanlow, and two breeder strains. The structures of the fungal and bacterial communities have been separately profiled using ribosomal intergenic spacer analysis (RISA) for each sample and will be analyzed to discern if there are any cultivar-dependent differences in these communities. We will also contrast the community structures in the Kanlow grown in Tennessee with that of Kanlow grown in Washington State.