Purdue specialist: Don’t let stored grain lose its cool this spring

WEST LAFAYETTE, IN -- After an unusually mild winter and with temperatures remaining above normal so far this spring, stored grain could be more susceptible to mold and spoilage from insects, a Purdue Extension grain storage specialist writes in a new article.

Klein Ileleji, associate professor of agricultural and biological engineering, recommends keeping bin vents closed and avoiding aeration until May or June.

"Aerating the grain early in the spring will warm it up to temperatures conducive to mold and insect pest growth and thus the security provided by cold winter aeration is rapidly lost," he writes. "It is also advisable to cover the fan intake when it is not being used in order to prevent passive warm air from aerating and warming up the stored grain."

Excess moisture should not be a problem this year because weather conditions last fall were ideal for field drying, alleviating the need for spring aeration, Ileleji said. Typically, corn should be dried to a moisture content of 15 percent for storage and soybeans to 13 percent. If the grain is to be stored for more than a year, the moisture content should be 13 percent for corn, 11 percent for soybeans.

Monitoring grain for temperature and moisture content is essential, Ileleji said. He advised farmers to use temperature sensors to help determine if stored grain is at risk from mold and insect development.

"Anecdotal evidence suggests that less than 30 percent of on-farm stored grain in Indiana is monitored using sensors," Ileleji said. "Most producers depend on their nose as the sensor. While this practice has been used for years, and most producers are comfortable with it, perceiving spoiled grain means that there is rather active biological activity in the stored grain."

Ileleji's article, Spring Management of Stored Grain, appears in the latest issue of Purdue's Pest & Crop online newsletter, available at

A safety harness rests atop a pile of grain inside a storage bin. A Purdue Extension specialist is advising producers to avoid aerating bins this spring to reduce the risk of mold and insect infestations.