Got heavy corn residue? Keep these 6 tips in mind
With this year's good corn yields and increased plant material, some farmers are concerned about dealing with all the residue. Properly handling the residue at harvest is key to preparing for the next crop. Here are a few key considerations for when you're handling a field with heavy crop residue from University of Nebraska Extension engineer Paul Jasa.
- Process the residue with the cornhead. Corn stalks and leaves must be processed down through the snapping rolls at harvest to make no tilling into corn residue easier. Knife to knife or tapered snapping rolls are more aggressive to lacerate and crush the stalks. By getting the stalks broken open and down to the soil, they are exposed to microbes and weather conditions that will help speed decomposition. With Bt corn hybrids, new disease packages, and in-season fungicide applications, processing the stalks with the cornhead is even more important as there is less natural breakdown.
Too often, intermeshing snapping rolls don't let the corn stalks between them and generally have considerable wear at the beginning of the flutes, directly behind the intake screws. In addition, the stripper plates usually wear more at the same point, making it difficult to cleanly snap the ears. Since the stalks aren=t processed through the rolls, they are left tall and leaning. While this catches more snowfall, it doesn't allow the stalks to decompose much before planting.
Numerous aftermarket snapping rolls are available to aid in processing residue. Many of them are tapered or a knife-to-knife design, such as those on most of the newer European corn heads being promoted to process residue. Usually, producers should avoid the chopping heads with the shredders underneath as they cost more, weigh more, and take more horsepower. In addition, the chopping corn heads process the residue too much, leaving it much more likely to blow around.
- Leave some of the corn stalk standing at harvest. A 12- to 18-inch tall corn stalk anchored and upright after harvest helps keep the residue in place, reducing residue movement by wind and water. It also catches snowfall and reduces wind erosion. The standing residue allows good air movement down to the soil surface, encouraging faster breakdown of the residue. Matted or flattened residue doesn't let the surface soil dry as quickly and may delay planting in wet springs. Leaving taller stalks at harvest may create problems when catching on planters or fertilizer equipment the next spring.
- Consider grazing the corn stalks or taking a strategic cutting to reduce residue levels and clean up volunteer corn. Some producers generate extra income by renting out the corn stalks for grazing or by harvesting the residue for feed or bedding. While this decreases the amount of residue, not all of the residue should be removed and it shouldn't be done every year. If mechanically removing residue, leave 8, 12, 16 or 24 rows standing every 48 rows to reduce wind erosion and trap snowfall. This may create some problems with planting since the soil and residue conditions will not be uniform.