Gary Johnson walks through a field of milo sorghum on his farm in Waukomis, Okla, Wednesday, Aug. 15, 2012. The government is on the verge of approving sorghum, a grain mainly used as l

 

              Gary Johnson walks through a field of milo sorghum on his farm in Waukomis, Okla, Wednesday, Aug. 15, 2012. The government is on the verge of approving sorghum, a grain mainly used as l
Gary Johnson walks through a field of milo sorghum on his farm in Waukomis, Okla, Wednesday, Aug. 15, 2012. The government is on the verge of approving sorghum, a grain mainly used as livestock feed, to make a cleaner version of ethanol. (AP Photo/Sue Ogrocki)