Increased Risk of Hay Fires

The Ontario Ministry of Agriculture, Food and Rural Affairs (OMAFRA) is trying to raise awareness of the unique increased risk of hay fires this year that could result in significant farm structure fires. Some hay that was cut during the dry, hot conditions in late May felt dry enough to bale but was not cured long enough for the stem to completely dry out. Damp hay is at risk of heating and spontaneous combustion, in a similar fashion to oily rags catching fire unexpectedly. Most instances of spontaneous hay combustion occur during the first three months in storage.

OMAFRA started getting reports of hay heating in storage in mid-June. Media reports suggest more farm structure and/or hay fires than average, although the cause of these fires is not always known at the time of reporting.

OMAFRA is encouraging all farmers with May-baled hay in storage to check it daily with a thermometer until September to ensure it is not heating. Because the remaining moisture is inside the stem, hay moisture probes are not a reliable way to check for a problem. Key temperature thresholds and guidance for farmers on how to manage hay that is heating can be found on Field Crop News.com.

The purpose of this release is to notify fire departments that may provide coverage in rural areas that there has been a noticeable increase in fires associated with hay. Fire departments may want to conduct education and prevention activities in their areas of service to make farmers aware of possible increased fire risks.