*

USDA leaves US corn stocks unchanged, baffling traders

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USDA reports US wheat inventories higher than trade

expectations

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Chinese demand a worry for US soy market

(Recasts to reflect market moves, updates headline, adds

closing prices)

By P.J. Huffstutter

CHICAGO, March 11 (Reuters) - Chicago Board of Trade

soybean futures ended lower on Tuesday for a third straight

session, coming under pressure from hefty South American

supplies hitting the global market and uncertainty over how U.S.

tariffs will affect domestic demand, traders said.

Corn fell during a choppy trading session, after the federal

government left domestic corn inventories unchanged in a monthly

supply-and-demand report - despite strong export sales and trade

tensions with top buyer Mexico.

Wheat futures ended lower after the U.S. Department of

Agriculture reported domestic and global wheat inventories were

bigger than trade expectations.

The CBOT's most-active wheat closed down 5-3/4 cents

at $5.56-3/4 a bushel. Corn ended down 1-3/4 cents at

$4.70-1/4 a bushel, while soybeans settled down 2-3/4

cents at $10.11-1/4 per bushel.

Weakness in the canola market weighed on soyoil

prices, which also carried over to pressure soybean futures,

traders said.

Traders and farmers are keeping a close eye on exports, with

U.S. tariff disputes with major buyers Mexico, Canada and China

threatening sales of U.S. agricultural goods. They said USDA

likely held off on changes as it waits to see whether the U.S.

implements fresh tariffs and how trading partners respond.

Fears that U.S. tariffs will hurt economic growth have

unsettled financial markets, while grain investors are wary that

China may shun U.S. soybeans altogether in favor of a bumper

Brazilian crop.

With the tariff war roiling between the U.S. and China, "the

question is, where are we going to sell the (U.S.) beans? No one

knows," said Jack Scoville, vice president at Price Futures

Group in Chicago.

For corn futures, some analysts were baffled why USDA kept

the U.S. corn export forecast unchanged, given the current pace

of sales.

"I get the whole conversation about trade and tariffs and

the unknown," said Angie Setzer, partner at Consus Ag. "But if

all you can do is predict the futures based on normal market

trends, as they have told me they do, I'm not sure how they can

rationalize not making an adjustment at this point."

(Additional reporting by Tom Polansek and Heather Schlitz in

Chicago, and Gus Trompiz in Paris and Naveen Thukral in

Singapore; Editing by Alan Barona, Janane Venkatraman, David

Evans, Alison Williams and Rod Nickel)