Stalk-chopping corn heads, commonplace in Europe, are becoming increasingly popular in the U.S. as a way to manage the growing mounds of crop residue. Tougher, higher-yielding genetically modified crops, coupled with reduced-tillage practices and corn on corn, have resulted in more cornstalks in fields.
Chopping the stalks into 6- to 8-in. pieces can help them decompose and flow better through planting and tillage equipment. But rather than relying on tractor-pulled stalk choppers, which require a separate field pass, a growing number of farmers are opting to buy corn heads with integrated stalk choppers that can both harvest corn and chop the stalks at the same time while combining.
“By using a chopping corn head in place of a conventional stalk chopper, there is an opportunity to economize as much as $20,000 on machinery as well as fuel and staff savings, not to mention less ground compaction,” says Peter Stark, managing director of Fantini North America.
Matthew Digman, an agricultural engineer at the University of Wisconsin–Madison, says most brands of chopping corn heads work about the same. Rotating blades, similar to those in a rotary mower, are mounted under each row unit behind the stalk rollers and are powered by the row-unit gearbox (see bottom left photo, Method One). Stalks are cut off and chopped up, leaving a blunt or shattered stem standing in the field.
“Geringhoff and Cressoni have a different take on how to chop the stalk,” Digman explains. “Stalks are chopped off at an angle, and the remaining stubble is vertically spliced open in an effort to further promote decay” (see bottom right photo, Method Two).
Chopping corn heads add weight to the combine and require more horsepower than a standard corn head. Estimates range from 1.5 to 7 hp/row, depending on conditions. Digman advises farmers to factor in the exact power required, and subsequent impact on combine productivity, and to review their current residue management practices before making a buying decision.