Straw is an agricultural byprouct, the dry stalk of a cereal plant, after the nutrient grain or seed has been removed. Straw makes up about half of the yield of a cereal crop such as barley, oats, rice, rye or wheat. In times gone by, it was regarded as a useful by-product of the harvest, but with the advent of the combine harvester, straw has become more of a burden, almost a nuisance to farmers (why, how?).