ASSUMPTION, Ill. — Farmers can readily see the negative impact of adverse weather, plant disease and pests on their yields. As its name implies, “invisible loss” can’t be observed but can be prevented by harvesting early and drying their grain, according to Gary Woodruff, conditioning applications manager for GSI.
Woodruff explains that invisible loss can occur when grain is allowed to dry down too long in the field. “Corn becomes mature at a moisture level somewhere between 26-35%, but there are biological factors going on inside that kernel between 30% and 15%,” he said. “The kernel is making normal changes to become a seed ready to sprout, and in that process, it cannibalizes some of the starches, some of the energy, from the kernel. This is often called respiration.”
That cannibalization, he says, causes a reduction in test weight, resulting in lower yield. “When corn drops to 15% moisture, as it does when harvested late, losses of 10-15% percent or more are common,” he notes. “So, the earlier you can get the crop out, the more yield you are going to have.”
Woodruff adds that this fall, because of the progress in maturity and predicted dry harvest weather in many parts of the country, it will be more important than ever to be on top of the first possible day corn is harvestable. “Otherwise, farmers could likely find themselves starting at a lower moisture than they expected and watching the moisture levels dropping faster than normal,” he says. “Timing will be critical to maximize this year’s yield.”
Woodruff adds that invisible loss isn’t the only risk of leaving grain to dry down in the field too long. Yield loss can also result from dry grain shatter during combining, as well as stalk damage, ear drop or downed corn caused by harsh weather.
Even factoring in lower commodity prices, Woodruff says the revenue lost due to in-field drying exceeds the cost for farmers to dry their own crop using today’s high-efficiency dryers. “Farmers think if they harvest wet, they will have higher fuel use for drying and it will slow their harvest,” he notes. “However, studies have consistently shown there is never a time that putting off harvest saves money.”
Grain Drying and Storage Recommendations
Woodruff offers these additional tips for properly drying and storing grain this harvest season to maximize grain quality and profitability:
- To safely store corn post-harvest through the following spring, moisture content should not exceed 15%. To safely store through fall, it should be no higher than 14% and to store for one year or longer, it must be held at 13 percent.
- As grain enters the bin, run aeration fans to equalize kernel grain moisture, which typically takes five to 10 days. This puts the grain in the best shape to store safely.
- Fines can’t be thrown as far as kernels. Repetitive coring that forms an inverted 10-foot cone for every 10 feet of depth as the bin is filled is a tremendous tool in minimizing fines in the center. It makes a major difference increasing in value as bins get larger.
- Soon after harvest, pull the bins with peaked grain down so the center is just below the corn at the wall. The grain will look somewhat like an M from the side, promoting air movement in the center. Leveling at this point is also a good practice.
- Watch the ambient temperature and use aeration fans to get the grain temperature below 50 degrees as soon as possible. Nearly all insect and mold activity ceases below this temperature.
- Check the grain weekly. Climb to the top of the bin, without entering, and observe whether there is a crust or any noticeable smell. An increase in surface moisture usually is the first sign of problems.
