Hay fire season: Moisture, temperatures and safety steps

Does anyone else feel that when Sept. 1 hits, it feels like we shift into road gear and just crank? Life in general right now just feels like it's running at warp speed — on the farm, at work and at home. I hope you are all able to enjoy this beautiful fall weather we are having and the crisp, amazing mornings with spectacular sunrises.

Our farm was blessed with a great second cut and baling of our 40-acre hayfield at my grandparents’. This year we were blessed with a great second cutting, unlike last year. This was a wonderful full cutting, and I was thankful for the dry-weather window to get it made, baled and home. I know we are all wishing for some rain and need it for our pastures, but it's been a great time period to get some hayfields cleaned up.

Some phone calls I have unfortunately gotten over the last few weeks have been related to hay moisture and emergencies of hay catching fire. Here are a few tips and notes from fellow educators Jason Hartschuh, Mark Sulc, Sarah Noggle and David Dugan.

“Usually, we think of water and moisture as a way to put a fire out, but the opposite is true with hay and straw, which, when too wet, can heat and spontaneously combust. This is more common with hay than with straw because there is more plant cell respiration in hay. When baled at moisture over 20%, mesophilic bacteria release heat, causing temperatures to rise between 130 F and 140 F. If bacteria die and bales cool, you are in the clear, but if thermophilic bacteria take over, temperatures can rise to over 175 F.

"The moist bales should be kept outside or in a well-ventilated area. Don’t stack the moist bales because that prevents the heat and moisture left in the hay from escaping. It is normal for hay to go through a 'sweat' in the first few days after baling. Internal temperatures of 110 F in the first five days after baling are quite common in our region and are not a big concern.”

For more information and the full article, visit agsafety.osu.edu/newsletter/ag-safety-stat/june-2018/emergency-management/hay-and-straw-barn-fires-real-danger.

Assessing the fire risk

—Most hay fires occur within the first six weeks after baling.

—Was the field evenly dry or did it have wet spots?

—Were moisture levels kept at 20% or less?

—If over 20% of hay preservative was used.

Critical temperatures and actions to take

—For 125 F, no action needed.

—For 150 F, hay is entering the danger zone. Check twice daily. Disassemble stacked hay bales to promote air circulation to cool the hay outside.

— For 160 F, hay has reached the danger zone. Check hay temperature every couple of hours. Disassemble stacked hay to promote air circulation to cool the hay. Have the fire department present while unstacking from here on.

—For 175 F, hot pockets are likely. Alert the fire service to a possible hay fire incident. Close barns tightly to eliminate oxygen.

—For 190 F, with the assistance of the fire service, remove hot hay. Be aware the bales may burst into flames.

—For 200 F or more, with the assistance of the fire service, remove hot hay. Most likely, a fire will occur. Keep tractors wet and fire hose lines charged in the barn and along the route where bales are to be stacked.

If you have questions or are unsure what your hay moisture level is or what the temperature of your bales is, reach out or find someone with the probes to test. Monitoring and daily observations are critical.

As we enjoy this cooler weather and start to prepare for the upcoming fall events, don’t forget about the Farm Science Review. This year’s theme, “Transforming Tradition,” is an invitation for visitors to explore new ideas while building on the roots of their agricultural heritage, said Nick Zachrich, Farm Science Review manager.

The 63rd Farm Science Review, hosted by Ohio State University College of Food, Agricultural and Environmental Sciences, will be held Sept. 16-18 in London, Ohio. The show offers access to more than 4,000 product lines and over 180 educational sessions led by CFAES researchers and Ohio State University Extension experts. OSU Extension is CFAES’s outreach arm. We have tickets for sale in the office still.

If you have questions, would like a farm visit or would like hay moisture or temperatures checked, be sure to call the office and ask for Janessa or email me.

Be safe in the fields and have a fantastic farm. Remember to stop and enjoy the amazing fall.

Janessa Hill is an ANR educator with Holmes County OSU Extension. She can be reached at hill.1357@osu.edu or by calling the office at 330-674-3015.