Corn With A Cover Of Grass

 

Researcher Jeremy Singer evaluates perennial groundcover grass growing between rows of corn.

 

The phrase "a double-edged sword" describes something that is beneficial in some ways but problematic in others. One example is removing maize stover (the husks, stems and leaves of corn plants) from fields. Maize stover is used to make cellulosic ethanol, a renewable biofuel. And renewable biofuels are beneficial to the environment. However, removing the stover can harm the environment because it can cause the soil to erode and lose nutrients.

 

Taking up this double-edged sword is Cynthia Bartel, a doctoral candidate at Iowa State University. She's finding a way to lessen the harm and increase the benefits of removing maize stover.

 

"While water and wind erosion are substantial problems for maize stover removal, soil quality preservation is an even greater constraint," she explained. Bartel needed to find a way to remove the stover but preserve the soil quality. So, she turned to previous research for ideas and found that cover or companion crops can improve soil quality. Bartel liked the idea of using cover crops, but was curious about a different type of cover crop.

 

Instead of annual cover crops, which must be replanted every year, Bartel continued research at Iowa State University (ISU) involving perennial groundcover, and specifically grasses. "We envision that perennial grass seed might need to be purchased and planted only every four to five years, which would greatly reduce expenses compared to annual covers." Using a perennial groundcover could be a win-win, including natural resources preservation in addition to reducing costs. However, Bartel needed to determine if perennial groundcover and maize are compatible. She also needed to determine if using a perennial groundcover crop is both environmentally and economically beneficial.

 

To explore these questions, the ISU team conducted a field study at two locations in Iowa. In some areas, they planted Kentucky bluegrass with the maize. In other areas, they planted creeping red fescue with the maize. The team closely monitored and analyzed the crops over two years. "The success of the system largely depends on using a compatible species," she explained. And compatibility depends on several factors.