The price of corn dropped again on Tuesday as a mix of sunshine, rain and moderate temperatures increased the likelihood of a record crop this year.
Corn for delivery in September dropped 3.75 cents, or 1 percent, to $3.68 a bushel on Tuesday.
The price of corn has slumped 30 percent since the end of April as the favorable weather has boosted the outlook for this year's crop. The US Department of Agriculture predicts that this year's crop, forecast to yield 13.9 million bushels, will come close to matching last year's record.
"The weather conditions are beyond good," said Sterling Smith, a commodities analyst at Citigroup. "We've had quite possibly the best weather conditions that we've seen in 30 years."
Wheat and soybean prices also fell.
The price of wheat for September fell to 5.5 cents, or 1 percent, to $5.25 a bushel. Soybeans for the same month dropped 13.75 cents, or 1.3 percent, to $10.58 a bushel.
In metals trading, gold, platinum and palladium edged lower.
Gold fell $7.60, or 0.6 percent, to $1,306.30 an ounce. Platinum for October delivery dropped $5.10, or 0.3 percent, to $1,488.30 an ounce. Palladium for September declined $2.30, or 0.3 percent, to $874.85 an ounce.
Silver was little changed at $21 an ounce and copper edged up 1 cent to $3.21 a pound.
In energy trading, the price of oil fell for a third day, dropping 17 cents, or 0.2 percent, to $104.42 a barrel.
Wholesale gasoline fell 1 cent to $2.88 a gallon. Heating oil was little changed at $2.85 a gallon. Natural gas dropped 7.7 cents, or 2 percent, to $3.77 per 1,000 cubic feet.