December corn opened 4 3/4 cents higher at 595 1/4 and established an early range of 585 1/2 to 597 3/4. The higher open attracted selling by locals and funds with moderate volume being reported by floor traders. Corn is losing to wheat again this morning, continuing the recent sharp trend, and trade in the spread was described as active this morning. Weekly export sales for corn, released before the open, came in at 323,500 metric tonnes for old crop and 499,600 for new crop for a total of 823,100. This was near the high end of trade expectations. Sales of 189,000 tonnes are needed each week to reach the USDA forecast for this year. Total sales to date stand at 98.1% of the USDA forecast versus a 5 year average of 95.2%. An oil spill has closed the Mississippi from New Orleans to the Gulf of Mexico today. Basis levels at the Gulf remain steady as traders there anxiously watch progress in containing the spill.