The lignocellulose in forage crops represents large source of biomass feedstock for conversion into energy-related end products. With new technologies and processes for biomass production and conversion approaching commercial reality forages could once again fuel agriculture. Some of the most extensively studied species for biomass feedstock production include forages such as switchgrass, reed canarygrass, and alfalfa. An advantage of using existing forages as bioenergy crops is that farmers are familiar with their agronomic management and already have the machinery, technology, and infrastructure needed to establish, manage, harvest, store, and transport them. Forage crops offer additional flexibility in management, because they can be used for biomass or forage and the land can be returned to other uses or put into crop rotation. The billion-ton biomass vision for 2030 developed by the US-DOE and USDA envisions about a third of biomass would come from dedicated perennial energy crops (i.e., forages), requiring about 55 million acres of cropland, idle cropland, and cropland pasture (permanent pasture was excluded from the analysis). How will large scale cellulosic energy farming affect the traditional forage-livestock industry if that scenario occurs? The recent experience with corn for ethanol demonstrates clearly the unpredictable reactions of markets, producers, and consumers to large-scale government programs. Large acreages of forage land have been diverted to corn production. This, along with higher corn grain prices, has increased feed costs for livestock producers. We should expect the same unpredictable reactions when cellulosic energy from forages becomes a reality.