Oregon Public Broadcasting

Investigators from the Oregon Department of Forestry and the Deschutes National Forest say they've wrapped up their inquiry into this month's Rooster Rock Fire in Central Oregon. But because the scene was poorly preserved they don't know if the fire was caused by people or by lightning.

The Rooster Rock fire burned more than 6,000 acres of forest and cost taxpayers nearly $6 million, so investigators had a real interest in finding out what caused it.

George Ponte: "I think it's just an unfortunate set of circumstances."

George Ponte is with the Oregon Department of Forestry.  He says when investigators arrived on the scene they looked for burn patterns to help them pinpoint the fire's point of origin.

George Ponte: "If you look at those burned fuels closely, you can actually figure out which way the flames came from when that fuels burned." 

He says that can sometimes lead investigators back to a lighting scarred tree or a campfire ring.  But in this case, Ponte says any clues left behind were destroyed when crews dug fire lines through the area to keep the fire from spreading.

Ponte says lightning was spotted in the area in the days before the fire. But the location where the fire started was also accessible by a recreation trail. 

He says the true cause will probably never be known.