GRAINS-Corn to contract lows, soy weak as U.S. harvest expands

(Recasts throughout with updated prices, quotes; changes byline, dateline from previous PARIS/SINGAPORE) CHICAGO, Sept 17 (Reuters) - U.S. corn futures fell nearly 1 percent on Monday, with nearby months hitting contract lows as the harvest of a bumper crop picked up speed in the Midwest and early yield reports were strong, traders said. Soybean futures also declined on harvest progress, along with disappointing U.S. soy crush data and ongoing concerns about U.S. trade disputes with top global soy buyer China. Wheat slipped as well. Traders awaited news on an expected new round of tariffs from Washington on Chinese goods, which would escalate a simmering U.S.-Sino trade dispute. U.S. President Donald Trump was expected to announce new tariffs on $200 billion in Chinese goods as early as Monday, and China has said it would retaliate.

As of 12:57 p.m. CDT (1757 GMT), Chicago Board of Trade December corn was down 2-3/4 cents at $3.49 a bushel after dipping to $3.48-1/4, a contract low. November soybean futures were down 4 cents at $8.26-1/2 a bushel, hovering above a contract low set last week at $8.21-1/4. CBOT December wheat was down 1 cent at $5.10-1/2. Corn fell on a mix of technical selling and seasonal pressure as combines rolled in the Midwest. The U.S. Department of Agriculture last week projected the average U.S. corn yield at 181.3 bushels per acre and the average soybean yield at 52.8 bushels per acre, both record highs. "We are accelerating harvest in the eastern Corn Belt," said Dan Cekander, president of DC Analysis, adding that yield reports from Illinois have been large so far. Ahead of the USDA's weekly crop progress report due later on Monday, analysts surveyed by Reuters on average expected the government to report the U.S. corn harvest as 10 percent complete and the soybean harvest as 5 percent complete.

Soybean futures were also pressured by a lower-than-expected monthly crush figure. The National Oilseed Processors Association said its members crushed 158.885 million bushels of soybeans in August, a figure that fell below a range of trade expectations. However, the figure still represented NOPA's largest August total on record, reflecting strong profit margins that encouraged an active crush pace. CBOT wheat futures were lower but the December contract held above last week's two-month low, underpinned by uncertainty about supplies in major exporters Russia and Australia. Possible frost damage over the weekend in western Australia was threatening to further dent a crop already diminished by drought in the east. A 630,000 tonne purchase by Saudi Arabia on Monday initially lent additional support to wheat futures, although traders said it was unclear if U.S. wheat would be used to fill the optional-origin order.

CBOT prices as of 1:03 p.m. CDT (1803 GMT):

Net Pct Volume

Last change change

CBOT wheat WZ8 510.75 -0.75 -0.2 53879 CBOT corn CZ8 348.75 -3.00 -0.9 105928 CBOT soybeans SX8 826.75 -3.75 -0.5 57400 CBOT soymeal SMZ8 306.90 -1.80 -0.6 41329 CBOT soyoil BOZ8 27.84 0.08 0.3 32586

NOTE: CBOT December wheat and corn and November soybeans shown in cents per bushel, December soymeal in dollars per short ton and December soyoil in cents per lb.

(Additional reporting by Gus Trompiz in Paris and Naveen Thukral in Singapore; editing by Jan Harvey and Tom Brown)