- Associated Press - Tuesday, February 25, 2014

BEND, Ore. (AP) - A 2012 fire that caused hazardous air quality in parts of Central Oregon is a good example of why forests should be thinned to prevent scorching wildfires, a state study concludes.

Fire suppression efforts left the woods in the Pole Creek Fire overgrown and prone to larger and more severe wildfires, says the study by the Oregon Health Authority and the state Department of Forestry.

The Pole Creek fire was the largest in Central Oregon in 2012, burning on more than 41 square miles of forest late that summer and early fall, the Bend Bulletin (http://bit.ly/1mG1PzP) reported.

Smoke from the fire degraded the air quality in Sisters, particularly during a nearly weeklong stretch in mid-September when the air reached levels the Oregon Department of Environmental Quality deemed hazardous.

The smoke also caused the air quality in Bend to reach levels considered unhealthy for sensitive groups.

But the study didn’t find significant health effects.

Health officials looked at hospital discharge data from Deschutes County but didn’t see an increase from the previous year in hospitalizations caused by smoke-related ailments, said Dr. Dave Farrer, a toxicologist with the Oregon Health Authority.

An examination of county death certificates in September and early October 2012 showed more deaths due to chronic respiratory disease - 14 compared with four the year before.

But Farrer said it is unclear whether the increase was a result of the smoke. All the 2012 deaths occurred more than 20 miles from Sisters, where the smoke was worst.

State foresters found evidence that more timber burned than might have if the trees had been thinned so that the fire burned in the underbrush and not so intensely.

They found the fire burned entire forest stands in 40 percent of the burn area, partially killed woods on 36 percent and spread through underbrush on only 24 percent.

“This fire apparently burned very hot,” said Teresa Alcock, a fire program analyst at the Oregon Department of Forestry who worked on the report.

___

Information from: The Bulletin, http://www.bendbulletin.com