Interest in biofuels has increased dramatically, with the promise of reduction of our dependence on foreign oil and claims of lessened environmental impacts due to their use. A great deal of analysis has been done on biofuels including ethanol and biodiesel from the use of food crops such as corn, soybeans and sugar cane. More recently, there has been an effort to use cellulosics, or nonfood plants, as feedstocks for both ethanol and “Bioheat”. Research has focused on the potential usage of “switchgrass” (Panicum virgatum) and other perennial tall grass species. Recent work has also been focused on some of the woody invaders in rangelands such as “mesquite” (Prosopis glandulosa) and “juniper” (Juniperus spp). Discussions of these efforts have been intense, with advocates and opponents alike conducting research and often simultaneously pressing for policy adoption. The urgency of the need for alternative energy solutions, whether real or perceived, may force alternative energy policy decisions to be made using incomplete data sets. This organized oral session will highlight work on all sides of this critically important topic. We will examine the energetic, ecological and economic costs and benefits behind the use of rangeland feedstocks in both ethanol and bioheat projects. Some key issues include effects of biofuel growth and usage on greenhouse gas emissions, ecosystem integrity of the system(s) being harvested, effects on biodiversity, projected energy balances and economic costs of production and use. The total area of native rangelands is diminishing at a rapid rate. Much of this loss of rangeland has been to cropping systems as well as to expansion of urban areas. Does the expanded interest in rangeland species as feedstocks for biofuels represent yet another hazard for this dwindling ecological resource, or would ecologically planned harvests offer another way in which these lands may be conserved or even restored? Alternatively, do we allow for the invasion of higher producing feedstocks, for instance woody plants invading grasslands, to increase energy sources at the expense of biomes? We have designed this session to maximize audience interaction with the speakers and have allotted time for a panel discussion at the end of the presentations so that these issues may be examined critically.