Bioenergy producer Poet-DSM last week issued a response to a Purdue report stating that removing corn stover from fields can have negative effects on the environment, such as greenhouse gas emissions and erosion. Poet stated that the levels of stover removal instituted in its contracts with corn growers are below the amount found to increase soil erosion or have measurable effects on nitrogen loss.
“The Purdue researchers modeled removal of 52% of the above-ground biomass and 38% (what they called the 'low end of the environmental impact scale' in their work),” the release states. “At POET-DSM, we’re contracting for 20-25% of the above-ground biomass. Farmers we work with are taking about 1 ton per acre and leaving about 3 tons or more of material in the field. On those fields, the data has shown that erosion is not a factor and nutrient replacement is minimal.”
Poet backs its findings with an ongoing study done in collaboration with Iowa State University and the U.S. Department of Agriculture researchers. “Basically, at the removal level that POET-DSM recommends, there is no reduction in yield, and removal rates are well within the sustainability limits,” said Dr. Stuart Birrell with Iowa State University.
"Environmental and Economic Trade-Offs in a Watershed When Using Corn Stover for Bioenergy" appears in the January 2013 issue of Environmental Science & Technology.