Does corn-on-corn have a future?
Continuous corn was kind of a dud this year. Average corn-after-corn yields were almost 30 bushels lower than corn rotated with soybeans.
But, that's not the way it's supposed to be. Corn-on-corn, at least on paper, should net more revenue than a corn/soybean rotation. Right?
"Many Corn Belt farmers have had about as much fun as they can stand, planting continuous corn. Two years of budget busting yields, when they might have made more money rotating beans with corn," says University of Illinois Extension specialist Stu Ellis. "But continuous corn is supposed to generate more revenue, and since that has not happened for two years, you want to know what is going on."
So, why has corn-on-corn tanked the last couple of years? There are some clear agronomic reasons it lagged in 2010 and this year. A lot of farmers didn't get their fertilizer applied in the fall of 2009. Then, says University of Illinois Extension crop production specialist Emerson Nafziger, the weather was cool and damp the following spring and a lot of corn fields didn't root down well, pulling yields lower.
"Last year it was easy to make the case that, with the wet fall and lack of fall tillage in 2009, large amounts of surface residue and cool, wet conditions at planting, followed by heavy rain and root injury, all added up to yield losses for corn following corn," Nafziger says.
But, last year, harvest went quick and farmers were able to get a lot of fieldwork done before winter. So, Nafziger says, field conditions were good leading up to what was eventually turned into a wet, cool spring after about 10% of the crop was planted.
"Once the calendar turned to May and it dried up enough for fieldwork, planting got underway in a big rush, with about 60% of the crop planted over the first 2 weeks of May. Many -- probably most -- fields planted during this period were wetter than would have been ideal," Nafziger adds. "And because fields that were corn the year before almost always dry out more slowly than those that were in soybean, those who started planting corn following corn in early May planted into even wetter and cooler soils than those planting after soybean."
So, this caused compaction and the "undoing" of a lot of that tillage that farmers got done last fall. "It also brought issues of residue interference, seed placement and effects of heavy equipment in many corn-on-corn fields," Nafziger says.
But, even though the last 2 years have been reasons to decide against continuous corn, Nafziger says looking ahead to the 2012 crop, there will have to be some corn-on-corn just to make crop size ends meet. And, just because it hasn't worked in the last 2 years doesn't mean next year will be strike 3.
"It is discouraging that, after corn-on-corn has done so well in recent years, we now have a second year of lower yields in many corn-on-corn fields. Many will find that their profitability will be higher with corn following soybean than corn following corn this year, even accounting for what have often been lower returns from soybeans than from corn in recent years," he says. "So as long as corn acreage stays near the 12 million acres of recent years, some 20% to 25% of Illinois corn will have to be corn following corn."