GRAINS-Soybean, corn, wheat futures slump on tariff uncertainty

By Tom Polansek

CHICAGO, April 2 (Reuters) - Chicago Board of Trade grain and soybean futures fell on Wednesday as traders worried that U.S. farm exports will suffer from new tariffs that President Donald Trump is expected to announce later in the day.

Trump has for weeks pegged April 2 as "Liberation Day", when he plans to impose an array of duties that could upend the global trade system. Details of the tariff plans were still being formulated ahead of a White House Rose Garden announcement ceremony scheduled for 4 p.m. Eastern Time (2000 GMT).

The new duties, which are due to take effect immediately after Trump announces them, rattled grain traders as the U.S. exports more than 40% of its soybean production. A disruption in agricultural export sales would hit farmers as they are struggling with weak crop prices.

China, the world's biggest soybean importer, already imposed tariffs on U.S. farm products last month in response to earlier Trump levies.

"The world awaits this afternoon's reciprocal tariff announcement," said Arlan Suderman, chief commodities economist for brokerage StoneX. "Until then, the markets remain nervous, fearing the worst, but hoping for the best."

The most-active soybean contract was down 5-1/4 cents at $10.29 a bushel by noon CDT (1700 GMT) after rising on Wednesday to the highest level in nearly a month. Corn futures Cv1 dropped 4-1/2 cents to $4.57-1/4 a bushel after three straight sessions of gains.

CBOT wheat also weakened, with the most-active contract down 1-1/4 cents at $5.39-1/4 a bushel. Wheat last week fell to its lowest level since July, while corn touched a December low.

U.S. farmers are preparing to increase corn plantings by 5% in 2025 to the highest in 12 years, while cutting soybean and acres to a five-year low, the U.S. Department of Agriculture said on Monday.

Sherman Newlin, an Illinois farmer, said he may start planting soybeans late next week after rains.

"Everybody is hoping we can get stuff planted and get higher prices," said Newlin, who is also an analyst for Risk Management Commodities.