WASHINGTON — The U.S. Department of Agriculture in its Aug. 10 Crop Production report forecast 2018 U.S. production of corn at 14,586 million bus, down 0.1% from 2017, soybeans at a record 4,586 million bus, up 4.4%, and all wheat at 1,877 million bus, down 0.3% from July but up 8% from 2017.

Average corn yield in 2018 was forecast at a record 178.4 bus an acre, up 1% from 176.6 bus in 2017. Harvested area of corn was forecast at 81.8 million acres, unchanged from the June Acreage report but down 1% from last year. The average soybean yield was forecast at 51.6 bus an acre, up 5% from 49.1 bus last year and the second highest on record after 52 bus per acre in 2016. Harvested area was forecast at 88.9 million acres, unchanged from June but down 1% from 2017.

If realized, soybean production would be record high, topping the previous record of 4,392 million bus in 2017. Corn production would be the third highest on record after last year’s 14,604 million bus and the record of 15,148 million bus in 2016.

Production of spring wheat other than durum was estimated at 614,154,000 bus, up slightly from the July forecast and up 48% from 416,236,000 bus in 2017 based on a yield of 47.6 bus an acre, unchanged from July and up 6.6 bus from last year, and harvested area of 12.9 million acres, unchanged from July but up 27% from 2017.

U.S. durum production was forecast at 73,432,000 bus, down 2% from July but up 34% from 54,909,000 bus in 2017. Average yield was forecast at 39.9 bus an acre, down 0.8 bus from July but up 14.2 bus from 2017, with harvested area at 1.84 million acres, unchanged from July but down 14% from a year ago.

Winter wheat outturn was estimated at 1,189,199,000 bus, down 0.3% from July and down 6% from 1,269,437,000 bus in 2017. Average yield was estimated at 47.9 bus an acre, down 0.1 bu from July and down 2.3 bus from 2017. Harvested area was estimated at 24.8 million acres, down slightly from July and down 2% from 2017.

The U.S.D.A. forecasts for corn, soybeans, all wheat, winter wheat and other spring wheat all were above the average of trade expectations while the durum forecast was slightly below the trade average.

Corn and wheat futures traded lower and soybean futures sharply lower after the U.S.D.A. report was released. Projected 2019 carryover of corn and soybeans in the U.S.D.A’s World Agricultural Supply and Demand Estimates report that were above average trade expectations added pressure to corn and soybean futures.

It was the first survey-based forecasts for corn and soybeans. Estimates were based on conditions as of Aug. 1.