The best rally for corn prices in 10 months meant U.S. farmers were frantic to sell from the mountain of grain they’d been hoarding.

Growers have been stockpiling supplies following a string of bumper harvests, waiting patiently for a rebound in prices. Their hopes have finally been answered after dry weather threatened crops in Brazil, sending futures traded in Chicago to their highest in nine months. With more than 50 percent of U.S. corn stockpiles stashed on farms as of March, the unexpected price gains had resulted in “quite brisk” sales and deliveries, Bunge Ltd. Chief Executive Officer Soren Schroder said in a telephone interview.

“We had a couple of days of very strong farmer selling,” Juan Luciano, the CEO of Chicago-based Archer-Daniels-Midland Co., said on a call with analysts on Tuesday.

When corn was trading near $3.50 a bushel in the beginning of April, the market was looking “bleak” and farmers held onto the old crop, said Joe Lardy, a research manager for farmer cooperative CHS Inc.’s hedging unit in Inver Grove Heights, Minnesota. By the middle of the month, prices had topped $4 for the first time since July, reaching the “magic” level that “triggered a lot of activity,” he said.

Corn futures for July delivery were up 0.1 percent at $3.80 a bushel at 10:42 a.m. on the Chicago Board of Trade. The most-active contract jumped 11 percent in April, the biggest gain since June.

The pace of farmer selling was slower last week as prices declined, Lardy said.