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Traders square positions ahead of Thursday's USDA crop reports

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Wheat up on technicals, short covering after 15-month low

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Corn mixed, soybeans firm on Argentine drought concerns

CHICAGO, Jan 11 (Reuters) - U.S. wheat futures firmed on Wednesday as a drop to 15-month lows in the previous session sparked technical buying and short covering, and as traders took positions ahead of key U.S. government crop reports, traders said.

Corn was mixed and soybeans edged higher, underpinned by concerns about weather-reduced crops in South America and as traders squared bets before the U.S. Department of Agriculture (USDA) data due for release at 11 a.m. CST (1700 GMT) on Thursday.

"The market is just perking up a little bit ahead of the report tomorrow," said Ted Seifried, chief market strategist for the Zaner Group.

"We continue to watch Argentine weather. The rains they got were as advertised ... still not enough coverage to fix the problem. And the mid-term forecast still looks concerning."

Hot and mostly dry weather is expected across two-thirds of Argentina's crop belt over the next 10 days, heaping further stress on the drought-hit region, according to the Commodity Weather Group.

However, drought in Argentina is likely to break in coming months, the Buenos Aires Grain Exchange said on Tuesday.

Chicago Board of Trade March corn ended a penny higher at $6.56 a bushel, while March soybeans gained 8 cents to $14.93 a bushel.

CBOT March wheat was up 9 cents at $7.40 a bushel after falling to the lowest level for a most-active contract since October 2021 a day earlier.

Sluggish U.S. export demand continued to anchor grain prices. Demand for U.S. soybeans is also winding down seasonally as a bumper Brazilian harvest is due to flood the market in the coming weeks.

The USDA on Wednesday reported 124,000 tonnes in old-crop U.S. soybean sales to undisclosed buyers. It was the third daily soybean sales announcement in four trading days. (Reporting by Karl Plume in Chicago Additional reporting by Gus Trompiz in Paris and Naveen Thukral in Singapore; Editing by Marguerita Choy and Matthew Lewis)