CHICAGO (Dow Jones)--Corn futures at the Chicago Board of Trade drifted lower Friday, giving back some of the week's gains on pre-weekend profit-taking.

December corn ended down 2 1/2 cents at $3.34 per bushel, and March corn ended 3 cents lower at $3.46 3/4 per bushel. In pit trades, speculative fund selling was estimated at 7,000 lots.

The market lacked fresh supportive news to extend the week's uptrend, with bearish near-term weather for late developing crops adding to the defensive tone, analysts said.

Large production outlooks in the face of only routine demand provided little fundamental incentive for buyers to aggressively push prices beyond the week's gains.

Futures had rallied in previous sessions, staging a technical recovery from a recent downturn on bearish crop conditions. The inability of the market to attract additional buying was an ideal opportunity for traders to book some profits and even positions ahead of the weekend.

However, downside movement was limited by the uncertainties of yield and output, particularly with Midwest crops remaining vulnerable to a frost threat, analysts said.

The ability of active contracts to hold above major moving average support levels on technical charts remained a bullish sign for buyers, providing optimism the market has its near-term lows in place, a CBOT floor analyst said.

Otherwise, traders are expected to take a cautious approach to market activity awaiting field reports as the fall harvest prepares to get underway.

T-storm Weather said rain will ends in the central U.S. Saturday, with many areas already drying including the U.S. Delta. Cool weather early next week will lead to minimum temperatures in the 30s Fahrenheit on Tuesday across the northern Corn Belt, but a killing frost stays north of crop areas. A much warmer weather pattern follows for a few days, which aids maturation since it also remains dry through at least Wednesday.

Next weekend, a cooler pattern is probable to return - but a damaging frost is not imminent and chances for a killing frost remain low. Beyond next weekend, unresolved issues exist with an extended period of dry weather less likely than seasonably wet weather, T-storm Weather said.

CBOT oat futures ended unchanged. December oats finished flat at $2.19 a bushel, and March oats closed flat at $2.32 1/2.

Ethanol futures settled slightly higher. November ethanol rose $0.005 to $1.626 per gallon, and December ethanol closed up $0.001 at $1.616.

-By Andrew Johnson Jr., Dow Jones Newswires; 312-347-4604