Cob Removal Treads Lightly on Soil

As stated in my last post, the U.S. Environmental Protection Agency’s Draft Regulatory Impact Analysis stated that corn stover is the most economical agricultural feedstock to be used to produce ethanol. Apparently, Iowa State University would agree.

New ISU research shows that using corn cobs for cellulosic ethanol will not harm soil nutrient content. The research was funded by POET as part of our ongoing internal study into the sustainability of using corn cobs as a feedstock for next-generation ethanol. According to the study, conducted on a test field near the Emmetsburg site, fertilizer treatment for a field in which cobs have been removed would be identical to treatment of a field in which cobs were not removed. ISU researchers will continue their work this year on the test plots, compiling more data to help farmers manage their land well while taking advantage of an additional revenue source from their fields.

Previous research by the U.S. Department of Agriculture showed that cobs contain only 2-3 percent of the measured nutrients of the above-ground corn plant. This has been confirmed by previous ISU research.

The new ISU research takes a closer look at data regarding soil quality and nutrient levels, the impact of cob and stover removal on future plant growth, and recommended levels of fertilizer applications, if any, for cob or stover removal. Once again, research seems to conclude that using corn cobs for ethanol makes sense economically and environmentally.