Grain futures closed lower Thursday on the Chicago Board of Trade with the dollar index flat and trader moving to take profits on the last day of the month. Corn was off 1 1/2 to up 1 1/4, soybeans were off 7 to off 10 1/4, wheat was off 6 1/4 to off 7 3/4 and oats were off 2 to off 3. Corn futures corrected lower with traders profiting on Wednesday\'s gains. Declines in Chicago wheat were modestly sharper than losses in Kansas City and Minneapolis. Soybean futures dropped with rain forecast for growing regions of Argentina for the next 10 to 15 days. The prices: Corn: Mar 7.40 1/2 up 1/4, May 7.42 up 1, Jly 7.33 1/4 up 1 1/4, Sep 6.15 1/4 off 1 1/2. Soybeans: Mar 14.68 1/2 off 10 1/4, May 14.59 3/4 off 7 3/4, Jly 14.49 1/2 off 7 3/4, Aug 14.19 1/4 off 7. Wheat: Mar 7.79 1/2 off 7 1/2, May 7.88 off 7 3/4, Jly 7.93 1/4 off 7, Sep 8.01 1/2 off 6 1/4. Oats: Mar 3.60 off 2, May 3.67 off 2 1/4, Jly 3.72 off 3, Sep 3.71 1/4 off 2.