Storing wet hay could cause barn fire, Purdue specialist warns

June 24, 2015  

WEST LAFAYETTE, Ind. - With parts of the Midwest experiencing wetter-than-normal weather conditions, a Purdue Extension forage specialist is urging farmers to make sure their hay is adequately dried before baling and storage to reduce the risk of barn fires.

 "With all the rain we've been having, some farmers might be tempted to put away hay that is wetter than recommended," said Keith Johnson.

Johnson said the moisture content of hay for storage should be no higher than 20 percent. If hay is not given enough time to dry or is stored prematurely, heat-tolerant microorganisms can develop in the bales, raising the temperature.

If the temperature of stored hay reaches 150 degrees Fahrenheit, farmers should take apart the bales or stacks to allow cooling air to circulate. If the temperature reaches 200 degrees Fahrenheit, a fire becomes very likely.

"Those kinds of fires happen every year, but the wet conditions this year make the risk even greater," Johnson said. "Growers should monitor the temperature of their stored hay and notify their local fire department of any potentially dangerous heat buildup."

Johnson said farmers could speed up the drying by laying the cut forage in a wide swath with a mower-conditioner. Hay cut in a wide swath is more exposed to sunlight and dries faster. The conditioner crimps the stems of newly cut wheat and allows moisture to evaporate faster.

He said an alternative to storing forage as dry hay is to let the cut forage wilt to 50 percent moisture content and allow it to ferment to silage. This is done using an individual bale wrapper or an inline tuber that exudes air by wrapping the bales in white plastic.           

Writer: Darrin Pack, 765-494-8415,

Source: Keith Johnson, 765-494-4800,

Ag Communications: (765) 494-2722;
Keith Robinson,
Agriculture News Page

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