FILE - A July 19, 2012, file photo shows a corn field near Springfield, Neb. The USDA is releasing its first estimate of the 2013 crop size in its spring planting report on Thursday, March 28, 2013. ... more 
FILE - A July 19, 2012, file photo shows a corn field near Springfield, Neb. The USDA is releasing its first estimate of the 2013 crop size in its spring planting report on Thursday, March 28, 2013. (AP Photo/Nati Harnik, file) less 
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Associated Press | Photo By Nati Harnik, file
Thu, Mar 28, 2013 12:25 PM EDT