US corn, soy, wheat stocks reach four-year highs as of Sept. 1, USDA says

(Adds analyst quotes and details on USDA wheat production estimates)

CHICAGO, Sept 30 (Reuters) – U.S. stockpiles of grains and soybeans reached four-year highs as of Sept. 1, but corn and soybeans fell short of analysts’ expectations, U.S. Department of Agriculture data showed on Monday.

Large supplies have weighed on prices, which hit 2020 lows this summer. U.S. farmers are expected to harvest a record soybean crop this autumn and the second biggest corn crop in history, according to USDA.

Corn futures extended gains at the Chicago Board of Trade after USDA issued its data, as stocks were smaller than analysts expected.

Corn stocks were 1.76 billion bushels, up 29% from a year earlier, and soybean stocks were 342 million, also up 29%, USDA said in a quarterly report. Analysts had expected 1.844 billion bushels of corn and 351 million bushels of soybeans, according to a Reuters poll.

“These corn numbers are speaking to the good corn exports we’ve had, especially to Mexico,” said Jake Hanley, managing director for Teucrium Trading.

USDA adjusted its estimate for last year’s U.S. corn harvest to 15.341 billion bushels from a previous estimates of 15.342 billion. It pegged the 2023 soy crop at 4.162 billion bushels, compared with a previous estimate for 4.165 billion.

For wheat, U.S. stocks were 1.986 billion bushels on Sept. 1, up 12% from a year earlier, USDA said. Analysts expected 1.973 billion.

In another report, USDA pegged U.S. wheat production at 1.971 billion bushels, down from its previous forecast for 1.982 billion. Analysts had expected 1.966 billion.

CBOT wheat futures this month reached their highest level since June amid concerns about poor weather hurting global output.

“The lack of a bearish surprise in the wheat numbers allows us now to focus on that new-crop production potential and the worries that come from that,” said Angie Setzer, partner at Consus Ag Consulting.

(Reporting by Tom Polansek in Chicago. Additional reporting by PJ Huffstutter and Karl Plume. Editing by Marguerita Choy)