While farmers are currently preparing for corn grain harvest, they need to consider phantom yield loss, moisture, and soil compaction.
Phantom yield loss occurs when corn is left to dry in the field, and although it causes a noticeable amount of yield loss, it’s primarily due to shelling loss on the combine, said Jeff Coulter, Minnesota Extension corn systems agronomist.
“If corn is standing good, and you’re not too concerned about stalk roll shelling losses at harvest, I think it’s okay to let it sit out there for a little while,” Coulter said on the Gopher Coffee Shop podcast. “Once the grain moisture drops to around 24% or 22%, that’s kind of the optimum time to start harvesting. When it gets to the upper teens, that’s when we can really expect increased header losses.”
In the last week of September, corn will dry about a 0.5% to 0.75% of a percentage point per day, Coulter said. As the harvest nears, it’s important to check the crop for readiness as well as hail damage. Coulter suggests cutting open stalks near the ground or pinching the base of the stalk. If 10% to 15% of the stalks are lodged, breaking, or hollow, he suggests harvesting them as soon as possible.
Harvesting during a wet season is sometimes impossible to avoid, but it does cause soil compaction issues that need to be mitigated. Though sometimes farmers turn to tillage, Coulter suggests that cover crops are a better solution.
“If you think you caused problems in a wet year, you can’t think you can come back and till it wet and expect it to take care of the problem,” he said. “This era with the popularity — and trendiness, maybe I should say — of cover crops is probably a lot better management strategy to introduce real soil structure, instead of just ripping it deep. It might have a lot more positive, long-term implications.”
The author and her husband own a sixth-generation dairy farm near St Johns, Mich.