Nick Fetty | April 7, 2015
Recent research by an Iowa State University professor suggests that farmers should consider various site-specific factors when deciding whether to sell corn residue for cellulosic ethanol production.
Mahdi Al-Kaisi – a professor of agronomy – published his findings in the Soil Science Society of America Journal last month. Along with co-authors Jose Guzman (a postdoctoral fellow at Ohio State University) and Timothy Parkin (a microbiology researcher for the U.S. Department of Agriculture – Agricultural Research Service), Al-Kaisi suggested that farmers consider factors such as “topography, tillage system, nitrogen application and the amount of organic matter present in their soil to determine how much corn residue [they should remove.]” Corn residue – or corn stover – is the plant material left behind after harvest and which can be sold to create cellulosic ethanol.
Al-Kaisi and his team have been working on this project since 2008. The research team conducted the research at two sites: One in central Iowa and one in the southwest part of the state. The researchers monitored the effects of removing of corn residue, soil organic matter, greenhouse gas emissions, and soil quality.
The researchers saw that an increase in carbon dioxide and nitrous oxide emissions on plots where the residue was removed coincided with increased nitrogen application. They also concluded that excessive corn residue removal can cause erosion.
“Residue removal has some real environmental impacts on soil health and water quality. It needs to be approached thoughtfully and on a site-specific condition basis,” Al-Kaisi said in a press release.