We subsidized the growing of corn to produce ethanol. What if we just used grass to make it. It turns out that the much more complicated fibers of grass evolved over the eons to resists digestion from microbes. During WWII, however, a kind of mold was discovered that turned military gear made from tough fibers into mush almost overnight. Now a Canadian firm is using the enzymes from that mold to turn straw into gold or at least into ethanol.