ADVANCE FOR USE SUNDAY, MAY 5, 2013 AND THEREAFTER - FILE - This March 29, 1937 file photo shows rippling dunes against a fence, farm home, barn and windmill in Guymon, Okla. This property was abandoned by its owner when destructive dust clouds forced him to move. "Everybody has watched this population decline for generations," says Ryan McMullen, state director of USDA rural development. "There has been a long-term sense of despair, but it now feels this latest drought might be too much to overcome. That's saying a lot for communities that have maintained a population since the Dust Bowl. These are tough, salt-of-the-earth folks that don't call it quits easily." (AP Photo)