Corn rockets to 3-year high as traders eye lower U.S. production

Chicago corn futures shot to a three-year high on Monday, after a tour of U.S. farm regions by analysts last week found that crops were in worse condition than many expected.

The most-traded corn contract on the Chicago Board of Trade (CBOT) Cv1 was up 2.5% at $5.21 a bushel at 0351 GMT after reaching $5.22, the highest since August 2023.

Prices are up 12% so far this month.

Wheat futures rose to their highest in two years as tit-for-tat attacks by Russia and Ukraine continued to curtail exports from Black Sea ports.

Elsewhere, crop ratings for French grain maize stabilised after dropping to their lowest on record during an exceptionally hot and dry summer, data from farm office FranceAgriMer showed.

In other crops, CBOT wheat Wv1 was up 1.8% at $7.12 a bushel after touching $7.13-1/4, the highest since May 2024, and soybeans Sv1 were down 0.4% at $12.34 a bushel.

So far this month, wheat has gained around 12% and soybeans 4%.

Continued export disruption could push wheat prices up further, Commonwealth Bank analyst Dennis Voznesenski said.

But the size of the Black Sea region's 2026 harvest is near record levels, he said. "A truce to not attack ports would cause a very fast price correction lower."

U.S. 2026 corn production will fall well below government forecasts, advisory service Pro Farmer said on Friday after a tour of seven major production states found subpar crops hurt by adverse summer weather.