Biorefineries are picky eaters. They only consume one or two types of plant matter. Researchers processed and experimentally measured ethanol production from five different herbaceous feedstocks. They examined two annuals (corn stover and energy sorghum) along with three perennials (switchgrass, miscanthus, and restored prairie). They determined that a lignocellulosic ethanol refinery could use a range of plant types without having a major impact on the amount of ethanol produced per acre, or per land area.