The computer program projected that none of the 55 farms would begin collecting cobs if wagon rental was $28,000 and cobs brought $40 a ton. If farm operators received $100 a ton from biofuels producers, B-21 projected 22 of the 55 farms would collect cobs.

"We found that at $60 a ton, farm profits increased $10 per acre of corn, but not many farms chose to collect cobs," Erickson said. "If that increased to $120 per ton, the profit reached approximately $37 an acre of corn plus cobs."


"That's a pretty hefty fixed cost to farmers," Erickson said. "If rental was reduced to $14,000, cob harvest became much more attractive."

The Purdue study also indicated:


• If paid $100 per ton for cobs, farmers likely would collect 96 percent more cobs under the most favorable operating conditions and costs than the least favorable operating conditions and costs.

• Break-even prices for cobs can differ significantly from farm to farm, depending on corn yield, farm size and production practices.


Study findings are contained in Purdue Extension publication ID-417-W, "The Economics of Harvesting Corn Cobs for Energy." The publication is available for free download online at

Funding for the research was provided by the Indiana Corn Marketing Council.