FARGO, N.D. – Destruction of BT corn stalks is a key requirement for increased worldwide corn production.
Longer stalks on the ground not only create the obvious barrier in spring seeding, they also provide perfect winter habitat for the European corn borer.
BT hybrids were developed in the first place to combat the European corn borer. But the good genetics that brought insect resistance brought along a bad characteristic that is frustrating corn growers everywhere.
To a certain degree, BT corn defeats its own purpose because stalks that aren’t destroyed in the fall provide a winter home for a variety of insects.
Read Also
VIDEO: Green Lightning and Nytro Ag win sustainability innovation award
Nytro Ag Corp and Green Lightning recieved an innovation award at Ag in Motion 2025 for the Green Lightning Nitrogen Machine, which converts atmospheric nitrogen into a plant-usable form.
Better residue management helps eliminate corn borer habitat and reduces the insect’s impact.
Residue management at the combine intake is gaining acceptance because it allows producers to eliminate the costly tillage operation used to destroy BT corn stalks. As diesel prices rise, more farmers are looking to their combine header as a residue management tool.
Geringhoff got into the specialized corn header business in 1980, long before the borer was a concern. Since then, generations of engineers have focused their attention on one thing – design better corn heads.
For combine engineers, a better corn head means better stalk destruction. Geringhoff’s latest Rota-Disc corn chopping head is one of the most advanced in the industry.
The unique design uses two stripping rollers that intermesh with a third roller, which is called the stalk destruction roller.
According to Geringhoff, carbide rotary knives operating close to the ground press the plant against stationary knives and tear the stalks from the soil for quicker decay of the stump.
Stalks are then fed to the rotary discs like thread on a spool. The stalk destruction roller uses 15 self-sharpening, carbide tipped discs to shred the stalks. The discs are spaced on 30 millimetre intervals and are mounted in poly bushings for quick service and replacement.
The result of this disc action is that most stalks are shredded to lengths of three to six inches for easy decomposition. About 60 percent of the stalks going through the Rota Disc fall to the ground in lengths less than four inches. Only 10 percent are longer than 10 inches.
In comparison, 70 percent of the stalks going through conventional lawn mower style cutters are 10 inches or longer. Only 20 percent of the stalks are shorter than four inches. Long stalks take longer to decompose, thus providing more habitat for the European corn borer.
The discs are set to slice at angles of 22 to 28 degrees. This same angle is what’s left on the stump remaining in the ground. Geringhoff research indicates this cut-off angle is optimal for maximum winter exposure. Exposure contributes to residue deterioration and elimination of the habitat for all insects.
The Rota-Disc gathering chain has an automatic tensioner that eliminates the need to manually make the adjustment. A beveled sprocket serves as a slip clutch on each gathering assembly, providing protection to the drive mechanism. The deck plates have a hydraulic adjustment that automatically keeps them in the optimal position to minimize cob loss.
Geringhoff said its Rota-Disc design is the only one on the market that saves weight by eliminating the frame. All components are bolted to the aluminum gearbox so weight extended in front of the combine is minimized.
The gearbox itself is a sealed oil bath with an internal slip clutch that protects all moving parts on each row unit. For service, the bonnet on each row unit can be removed by unlatching three pins. Only one tool is required to change a gathering chain.
When harvesting downed corn, the Rota-Disc has a snout adjuster in the cab. The operator can compensate for changing conditions by changing the snout angle. Also for downed corn, a hydraulically driven snail option can pull crop into the header.
The Rota-Disc has adapter kits so it can quickly switch from one brand of combine to another.
Compared to conventional lawn mower style stalk cutters, the Rota-Disc draws an additional three horsepower per row unit.
For details, contact the Geringhoff North American headquarters in Minot, North Dakota, at 701-852-1876 or visit www.geringhoff.com.
