Riverhead firefighters doused a fire on a farm north of Sound Avenue this afternoon, where numerous rolls of baled straw caught fire.
It was spontaneous combustion, Riverhead Fire Department spokesperson William Sanok said. The bales heated up and had just enough moisture in them to catch fire, Sanok said.
Moisture in baled hay or straw causes chemical reactions that produce flammable gas, which when the bale’s internal temperature gets hot enough, can spontaneously ignite.
About 20 bales were involved, Sanok said.
A dozen Riverhead firefighters with two trucks and a tanker responded to the 12:30 p.m. call, he said.
It took about 90 minutes to put the fires out and make sure the bales weren’t still smoldering inside, which required firefighters to take them apart to expose and water the center, Sanok said.
No one was injured in the incident.