Corn stover harvest adds benefits for farmers
By Jennifer Carrico
DuPont Pioneer experts have concluded that sustainable corn stover harvest requires that only a portion be removed from the field. Leaving sufficient stover behind meets other critical needs, including mitigation of soil erosion, maintenance of soil organic matter, and sustained soil fertility.
DuPont Pioneer Agronomy Research Manager Andy Heggenstaller discussed corn stover removal during the In the Field of Discovery media event held at the Pioneer headquarters in Johnston, Iowa.
"With the addition of the DuPont Cellulosic Ethanol plant near Nevada, Iowa, we have been involved in a lot of research on harvesting corn stover and how it will affect the crop ground," he said.
The Nevada plant is expected to be completed by mid-2014 and will produce 30 million gallons of cellulosic ethanol per year, using corn stover from 815,000 acres in a 30 mile radius of the plant.
While an abundance of corn stover will be needed to make the ethanol at this plant, Heggenstaller said they want to be sure to stress that they want corn farmers to produce grain first and this will just give them another source of income.
Some of the research that has been done shows a yield increase on acres where corn is grown year after year because farmers won't have to deal with the residue left after harvest.
"When corn stover is not removed, it can contribute to some disease and pest problems in the following years," he said. "Partial stover harvest can help to manage increasing residue levels moving forward."
He also said some research shows on average that 5,000 plants per acre can be added to fields where stover is removed.
Some differences are seen in fertilization needs as well. Corn stover does not put any nitrogen back on the ground, but it will add potassium and phosphorus. Farmers need to understand that there will be management changes with the changes in how much residue is left on the ground.
"When considering stover harvest, growers should be thinking where they want to go with crop production, not where they are today," said Heggenstaller. "As grain yields and residue levels increase, it become more sustainable and economical to harvest a portion of stover and use it to produce other products than to till it into the soil."
Jennifer Carrico can be reached by phone at 515-833-2120, or by email at firstname.lastname@example.org.