Iowa plants to offer farmers cash for corn cobs

Two new technologies offer the promise that corn growers could turn their cobs into cash.

Cobs, the refuse left behind after harvest, are now plowed back into fields. But companies from California and South Dakota plan to start changing that by building two plants in Iowa, one to turn the material into ethanol and another to produce fertilizer.

"We're excited about it," corn farmer Jim Boyer said, "that there's an opportunity for another profit stream off our farm."

Boyer already sells much of the corn from his farm in Ringsted in northern Iowa to a traditional ethanol plant in nearby Emmetsburg. Most ethanol in the U.S. is made from corn kernels.

But a $200 …