CHICAGO: Chicago Board of Trade corn futures hit a three-month high on Wednesday after the US Department of Agriculture reported smaller-than-anticipated US plantings Tuesday and as dry, hot weather forecasts threatened to stress crops, traders said.

CBOT September corn ended up 9 cents at $3.50-1/2 per bushel, after reaching $3.53-3/4, the contract's highest level since March 31. Forecasts called for above-average US Midwest temperatures and below-normal rainfall in early July as corn begins its key pollination phase, potentially stressing crops and lowering yield prospects.

The USDA on Tuesday said farmers planted 92.0 million acres of corn this spring, down about 5 million acres from its March 31 forecast of 97 million acres, the biggest March-to-June drop since 1983. The figure fell below the lowest in a range of analyst expectations.

The data came at a time when commodity funds hold a large net short position in CBOT corn, leaving the market vulnerable to bouts of short-covering.

The US Energy Information Administration said weekly production of corn-based ethanol rose for a ninth week, to 900,000 barrels per day, while stockpiles fell for a 10th week to 20.164 million barrels.

Ahead of Thursday's weekly USDA export sales report, traders expected the government to report US corn sales in the week ended June 25 at 450,000 to 900,000 tonnes (old and new crop years combined).