The rising demand for corn to make ethanol is hitting the pocketbooks of some movie-goers.

"Ethanol is the cause of the high popcorn prices," said Charles Cretors of C. Cretors & Co. in Chicago, which makes and supplies popcorn-popping machinery to the snack-food industry and movie theaters.

Popcorn differs from field corn, a commodity used in livestock feed, food additives and ethanol. But the price popcorn farmers receive stays above the price of field corn, which at more than $3 per bushel is up 37 percent from a year ago as production of corn-based ethanol soars.

The reason is that popcorn requires more care than field corn, and popcorn processors pay farmers a premium for it. The key to successful popcorn is the roughly 13 percent moisture inside each kernel, which makes it explode under heat.

Alan Teicher, who owns two theaters in Troy, north of Dayton, raised popcorn prices 25 cents to a range of $4.25 to $5 in anticipation of a 13 percent hike in the price he pays for popcorn.

"That's the largest increase I've ever heard of," said Teicher, who's been in business for 39 years. "We can only absorb so much of these increases before we pass them on to the customer."

In 2006, U.S. farmers devoted 214,243 acres to popcorn and harvested about 890 million pounds. The leading popcorn-producing states are Ohio, Illinois, Indiana, Iowa, Kansas, Kentucky, Michigan, Missouri and Nebraska.

Charles Profit, 66, who is raising 1,400 acres of popcorn this year in Van Wert and Mercer counties with his brother, Dale, figures his family should receive an average of at least 13 cents per pound for this year's popcorn crop. They received an average of 9 cents per pound for last year's crop.

But all is not well.

Dry field conditions have hurt popcorn plants during their critical pollination period, Profit said. Despite timely rains last week the family could lose much of its crop if rains aren't consistent for the rest of the summer, he said.

"Price never makes up for a short crop," Profit said.