By: The Working Forest Staff
As the West’s fire seasons grow more intense, a team of Oregon State University researchers is looking for ways to keep blazes from spreading.
They’re targeting the formation of embers, which can thwart fire lines by riding the wind for miles to start new fires.
According to a report in The Statesman Journal, that’s what happened last September during the catastrophic Eagle Creek Fire, when embers jumped two miles across the Columbia River to Washington. The fire burned for three months, scorching 50,000 acres, before being contained.
With funding from the federal government’s Joint Fire Science Program, David Blunck, an assistant professor of mechanical engineering, is leading a project to predict how embers form and spread.
The team is testing variables such as temperature, wind speed, timber species and branch diameter.
In the lab, they’ve used a small-scale wind tunnel to study ember formation in dowels made of different types of timber.
“With a camera, we determine how long it takes for a large piece of dowel to break off,” Blunck said. “Ultimately, how long it takes to break off is indicative of how long it takes to generate embers.”
In the field, they’ve burned more than 120 trees 12- to 14-feet tall, counting and measuring the embers that are released.
“Our working hypothesis now is that ponderosa generates a lot of embers because it has a very high fuel loading, or more needles,” said Tyler Hudson, a graduate student in the College of Engineering who is working on the project.
And, working with the Nature Conservancy of Oregon, they’ve observed controlled burns in the forest.
“We were able to put fireproof fabric around and collect embers on that, getting data representative of an actual fire,” Blunck said.
The researchers also use an infrared camera to look at embers lost into the air.
So far, the team has tentatively found that branch diameter is the biggest factor determining the formation of embers.
See full report here.