Soybeans to 1-week low on better-than-expected crop ratings

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Weekly USDA data shows stable soybean crop conditions

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Corn futures dip as U.S. harvest starts; wheat steadies

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Market awaits monthly USDA reports due Thursday

(Updates with closing U.S. prices)

By Julie Ingwersen

CHICAGO, Sept 10 (Reuters) - Chicago soybean futures fell to a one-week low on Tuesday, with the benchmark contract retreating back under $10 a bushel as better-than-expected U.S. crop ratings bolstered production prospects and eased worries about recent dry weather.

Corn futures declined in range-bound trade while wheat futures rose as market players squared positions ahead of key monthly crop estimates due on Thursday from the U.S. Department of Agriculture.

Chicago Board of Trade November soybeans settled down 20-3/4 cents at $9.97-1/4 per bushel after dipping to $9.95-3/4, the contract's lowest since Sept. 3.

Most-active CBOT corn futures ended down 3 cents at $4.04-1/4 a bushel but stayed inside of Monday's trading range, while CBOT wheat finished up 5-3/4 cents at $5.74-1/4 a bushel.

Soybeans fell after the USDA in its weekly crop progress report late on Monday kept its good-to-excellent score for the U.S. soybean crop unchanged at 65%, contrary to market expectations for a decline.

"That suggests that observers are still quite impressed with this year's crops ... raising concerns that USDA might raise its yield estimates" in Thursday's monthly crop reports, StoneX chief commodities economist Arlan Suderman wrote in a client note.

The USDA on Monday also said the U.S. corn harvest was 5% complete, slightly ahead of trade expectations.

Analysts surveyed by Reuters ahead of Thursday's monthly reports on average expect the government to leave its U.S. 2024 soybean yield forecast unchanged at 53.2 bushels per acre, but estimates ranged from 52.0 to 54.9 bushels. Analysts on average expect a slight reduction in the USDA's corn yield estimate.

Investors also await U.S. inflation data on Wednesday and a U.S. presidential debate later on Tuesday for clues about interest rates and wider economic policy.

Wheat futures ended higher but rallies were capped by cheaper Black Sea export prices, despite uncertainty over the size of Russia's crop.

"Wheat is up on short covering," said Tom Fritz, a partner with EFG Group in Chicago. Given expectations for large U.S. corn and soybean harvests, wheat "might be the least bearish of the three markets, so that prompts some inter-market spreading," Fritz said. (Reporting by Julie Ingwersen; additional reporting by Gus Trompiz in Paris and Naveen Thukral in Singapore; Editing by David Gregorio)