Where do you get that from? Using waste from the forrestry industry won't take grainland out of production. And as for using cropland to produce cellullose - research is going on right now using canola, mustard , flax ,corn stalks and other discarded cereal straw as sorces of cellulose for ethanol production too see which yeilds the most efficiently. So in conclusion You can seed crops like switch grass for cellulose for ethanol production and take land out of production of food but it is NOT required. You can use other sorces of celluose such as crop residues. People really need a course in thinking out side the box.