Managing residue in any no-till system can be a challenge with today’s high-yielding transgenic hybrids.
Ultra-narrow rows can make this even more challenging, as grain and stalk dry-matter yields are generally 5% to 7% higher. In dry years, grain and stalk dry matter yields can be as much as 7% to 12% higher in ultra-narrow rows than 30-inch rows.
Thus, overall, residue levels in ultra-narrow rows tend to run about 10% higher than 30-inch rows.
As corn yields continue to climb, residue amounts also continue to climb. The ratio of grain dry matter to whole-plant residue has increased from about 45% grain in the early years of corn hybrid development to 50% to 55% grain in today’s hybrids.
This indicates plants have become more efficient at moving nutrients to the grain. However, the amount of grain relative to residue is not growing fast even with high-yielding hybrids. We’ll see increasing amounts of residue to manage as grain yields increase.
On our farm, we raise corn in 20-inch rows. There are several common-sense keys to managing residue in these narrow rows to establish consistent crop stands. I’ll begin at harvest-time with tips for managing residue.
For years, we’ve made a point to use spreaders on our combines to evenly spread residue. This practice was generally adequate at harvest in the early days of no-till when hybrids produced less residue. But today, we need more residue management at harvest.
As corn residue levels have risen…