Grain futures started Wednesday's trade sharply higher on USDA's slashing of projected corn and soybean yields and demand. Then, the latter seemed to gradually outweigh the former and traders responded, sending the grains to sharply lower closing prices.

At the close of Wednesday's open-outcry session, the July corn futures contract was 10 3/4 cents lower at $7.50 1/4, the September contract was 14 1/4 cents lower at $7.04 1/4 and the December contract was 13 1/2 cents lower at $7.04. Soybeans shared corn's slide; the July contract finished 24 3/4 cents lower at $16.24, August beans were 16 lower at $15.74 1/2 and September beans were 16 1/4 lower at $15.41 1/2.

Wheat joined the bearish party, but didn't stay long and ended slightly higher; July wheat was 4 cents higher at $8.08 3/4, September wheat was 6 1/4 higher at $8.27 1/2 and December wheat was 3 3/4 higher at $8.39.

The mostly lower closing prices ended a roller coaster of a session Wednesday after USDA released grain supply/demand numbers that show U.S. crop yields are sliding fast. But, at the same time, USDA cut feed usage and export demand. Early in the session, yield numbers kept the grains higher until about mid-session, when traders seemed more focused on the lighter demand than the lighter yields.

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