WEST LAFAYETTE, IN -- Grain producers heading into harvest should carefully monitor the moisture level of their crops to help avoid spoilage during storage, a Purdue Extension expert says.
Klein Ileleji, associate professor of agricultural and biological engineering and a grain storage specialist, said excess moisture could be a problem for some crops after record rainfall earlier this season caused flooding and ponding in some parts of the Midwest.
While crops in one part of a field might have a high moisture content due to flooding, crops on higher ground might be drier, he said.
Mixing the grains from different parts of a field could help reduce the chances of spoilage.
"Rather than using the low or high moisture extremes as the basis for setting your final target moisture, use the average moisture," Ileleji said. "That is, mix wet and dry grain batches during harvest and dry them to help reduce moisture variability."
Once the grain is thoroughly mixed, Ileleji advised running bin aeration fans for 7-10 days so the grain is cooled to the ambient temperature of the surrounding air and moisture levels equalize in the bin. Depending on the weather, bin size and fan specifications, farmers may need to run fans for half a day or more for grain temperatures to reach ambient temperature levels.
"Cooling grain adequately to ambient temperature is an important step in preserving storage life," he said.
Once the ambient temperature is reached, Ileleji recommends "ambient aeration," that is, running the grain fan continuously to cool grain to below 50 degrees Fahrenheit. Temperature cables are useful to monitor grain cooling while deep bin probes or triers are used to sample grain for moisture, he said, especially to ensure that the top 5-6 feet below the surface is adequately dried.
Ileleji offered these grain storage tips:
* If corn is to be stored for a year or less, it should be dried to a moisture content of 14-15 percent. If it is to be stored more than a year, it should be dried to 13 percent. If the corn is of poor quality, those numbers should be reduced by 1 percentage point.
* Soybeans should be dried to a moisture content of 13 percent if they will be stored for six months, 12 percent for a year and 11 percent for more than a year. As with corn, if beans are especially of poor quality, those numbers should be reduced by 1 percentage point.
Ileleji advised cleaning grain dryers at least once a week during aeration to avoid buildup of trash and debris, which can reduce dryer performance and cause a fire. He also said farmers should never work alone in or around a grain bin.
"Remember safety procedures, be cautious and avoid hurrying," he said. "Don't let the extra demands of a challenging harvest season push you into a dangerous situation."