There are still many acres of corn standing in fields. Safe to say, many farmers are still likely filling their bins.

Now is the time to make sure grain is properly stored for overwintering.

Storage problems often occur in grain bins due to inadequate cooling, which results in condensation and crusted grain layers. Mold can result from high moisture content, excessive fines and damaged grain from high drying temperatures.

Penn State Extension has compiled several steps to ensure proper grain storage over winter:

1. Keep grain at 40 degrees F. Grain is typically 15% to 30% moisture when placed in a bin. A dryer must then bring the moisture content down to 13% or less to minimize the impacts of insects, fungi and bacteria. Temperature also influences the development of these organisms, with most insect reproduction and fungal growth halted below 50 degrees. A good target is to keep winter grain temperatures around 40 degrees.

2. Know when to aerate. Aeration should begin when the average of the daily high and low temperatures is 10 to 15 degrees lower than the grain temperature. Final grain temperatures should be checked by sampling 1 foot into the upper surface of the grain. For some aeration fans, this final cooling cycle could be up to 200 hours.

3. Monitor grain bin once a month. Monitoring of grain bins is essential to ensure proper moisture and temperature are maintained. Grain temperatures can be as high as 100 degrees, even in winter. A grain bin should be monitored once a month during the winter to measure grain temperature, moisture content, and insect and fungus activity. Use a grain temperature probe, a moisture probe and a tiered insect probe for checking mold and insects.

4. Use surface dressing for insect control. After the grain is binned and leveled, a surface dressing can be applied to prevent insects from entering the grain surface. DDVP resin strips should also be hung in the head space to control Indian meal moth.

Hot spots in the grain mass may indicate that insect populations are developing. If these are found, aeration should be initiated at once to lower the grain temperature and moisture content.

Do not aerate on warm or moist days, as it can increase the two. If an infestation occurs despite these precautions, fumigation of the grain will be necessary.

5. Use residual after storage. After grain is removed from the bin and is properly cleaned, a residual spray can be applied to the bin walls and floor to prepare for next year’s crop. This practice is especially important if the grain will be stored for nine months or more.

Source: Penn State Cooperative Extension