Brush fire in 'The Desert’ in Marlborough could burn for months. Here’s why.

MARLBOROUGH - It took three days, more than 50 agencies and more than 150 firefighters to beat back a 25-acre brush fire, but it will likely be burning for months, a fire official said on Monday.

The brush fire in an area called "The Desert" in the Marlborough-Sudbury State Forest off Concord Road has moved underground and will be closely monitored for the next few weeks, Assistant Fire Chief Jeff Emanuelson said.

"It's 100 percent contained, but we can't say it's extinguished," he said. "The fire is still burning underground. It could be like that for months. It may burn until we have a snow cover."

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On Friday at 11:30 a.m. the Marlborough, Sudbury and Hudson Fire Departments, along with the state Department of Conservation and Recreation, all went to Concord Road after several calls about smelling smoke. They discovered several acres of brush were burning approximately 1 mile from the road and it was quickly spreading.

It is possible the fire had started days earlier, but had not been discovered, Emanuelson said. He said a resident who is a meteorologist had a device that tracks lightning and there had been lightning activity in the area of the brush fire on Wednesday.

"People told us they had started smelling smoke two days before," the deputy chief said.

The fire department immediately reached out to state Fire District 14 to send strike teams to help with the fire. A state Fire District is a regional task force set up by the state and made up of personnel from fire departments in various regions.

The crews fought the fire all day on Friday and continued again on Saturday and then again on Sunday before it was contained, Emanuelson said.

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The smoke was so heavy that residents in several communities, including Hudson, Framingham, Natick, Sudbury, Wayland and Weston, called 911 to report smoke in their neighborhoods.

Reinforcements needed because fire was difficult to fight

The fire was difficult to fight for several reasons, Emanuelson said. It was a hot and humid weekend with temperatures in the 90s, meaning fire crews had to be rotated often to protect them from dehydration and heat exhaustion. The fire was also in a remote area, he said.

"The biggest issues we were dealing with were the heat and the weather conditions and the toll it was taking on the personnel," said Emanuelson. "Not only did we need to take care of the fire, but we had to take care of the firefighters."

Because of that, the fire department called in mutual aid from several communities and task forces. In all, there were eight task forces from the state, as well as firefighters from 50 communities. There were more than 150 firefighters, as well as paramedics and other public safety personnel there throughout the weekend, Emanuelson said.

Drought conditions in the area haven't helped

The drought has led to several brush fires recently. There had been brush fires in Natick and Framingham this month, and there were brush fires in Milford and Bellingham over the weekend. The Holliston Fire Department was fighting a 5-acre brush fire off Winter Street on Monday. The National Weather Service out of Boston had daily weather statements in the past week warning of brush fire dangers due to the drought and wind.

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The dry conditions helped the fire spread, Emanuelson said.

"The drought conditions created a very deep-seated fire," he said. "It burned into the root system, a foot to a foot and a half underground. We would have areas where the fire would travel underground and pop up behind our personnel out of nowhere."

Despite the length of the firefighters being out there, Emanuelson said there were no major injuries. He said there were some "very minor," injuries, including some bee stings and some heat exhaustion, but no one had to go to the hospital.

Firefighters will be monitoring the scene for the next few days and Monday's rain will likely help control some hot spots.

It's not known exactly what caused the fire.

"We will probably never know what actually started it," said Emanuelson. "It could have been the weather issues. It could have been someone riding an ATV and the muffler got so hot it ignited it. there's nothing specific that points to a definitive cause."

Norman Miller can be reached at 508-626-3823 or nmiller@wickedlocal.com. For up-to-date public safety news, follow Norman Miller on Twitter @Norman_MillerMW or on Facebook at facebook.com/NormanMillerCrime.

This article originally appeared on MetroWest Daily News: Marlborough brush fire contained, could burn for months