Keep Stored Grain Cool
When you first learned how to store grain, you were probably taught to warm the grain to within 10° to 15° of the outside temperature during summer. Recently experts have found more benefits from keeping grain cool.
Insect infestations and mold growth are more likely to occur at warmer temperatures. Insects thrive between 70° to 90°. Keeping grain cool, 40° in northern regions and 50° in southern states, decreases the risk for insect reproduction and activity.
There are some people who believe condensation will occur, particularly near the bin wall, if grain isn’t warmed to near outdoor air temperatures. This is not the case, says Ken Hellevang, North Dakota State extension ag engineer.
“Cold or cool grain has been safely stored through the summer for many years,” he adds.
Condensation forms on cool surfaces when warm, moist air comes in contact with the cool surface. Think of the condensation that forms on a glass with ice water. In the case of stored grain, warm, outdoor temperatures heat the bin wall, so conditions for condensation on the interior of the bin wall don’t exist. The bin wall is warmer than the grain and the air in the stored grain.
“There also has been concern that moisture will move from the warm grain near the bin wall into the cooler grain away from the bin wall,” says Hellevang. “However, when 16 bins of grain were monitored through a summer, no statistically valid change in grain moisture content occurred within 4 feet of the bin wall.”
According to Hellevang, many grain storage problems that have been blamed on leaving grain cold during warmer months are actually the result of condensation during the fall and winter. Condensation can form on the interior of a grain bin wall when warm grain is placed into a bin with a wall that is cool because of cold outdoor temperatures. Reports of grain sticking to the bin wall and deteriorating may be due to condensation in the fall causing the grain to increase in moisture content and then deteriorate during warmer months due to mold growth.