Special Fire Study Just Weeks Away in Vanderhoof

Sunday, July 17, 2005 04:02 AM

crown fire (courtesy B.C. Fire Center)

There are more than a hundred forest fires burning in Quebec right now, at least 4 are out of control. Forest FIre fighters from the Prince George Fire Centre are helping to battle the flames in Quebec, but as they fight to douse the flames in that province, their colleagues here at home are preparing to set some fires as part of a special study.

Some time next month a unique set of fires will be tested in the Tatuk Lake area near Vanderhoof. Dave Marek is a Forest Fire Protection Technician, and a Fire Behaviour Specialist with the West Fire Center centered in Smithers. The experimental fires are to assess the differences between flames in a natural, moist green forest, and fire in a beetle kill stand.

"Our front line observation is that the beetle kill fire is different, but we don't know how much faster it burns" says Marek. "Think of it this way" he says, "sparks from a bon-fire are carried up in a column of heat, then gravity takes over, and they fall back down, if that spark was to land on your green moist lawn, no real damage would be expected. But if the same spark lands on a dreid out brown patch of grass, the ignition would be faster, and the fire would spread."

Marek says the situation is similar in a stand of beetle kill trees "When flames are raging through a beetle kill fire, the same column of heat carries debris into the air, but when the debris falls, it's dropping on dry, dead beetle kill trees, and before you know it, there is "crown fire" happening, and it's jumping from the top of one tree to another." And that makes a big difference in how you battle the flames.

The usual method of attacking a forest fire is direct, doze out a guard zone, and the fire normally doesn't jump that guard line. Beetle kill fires seem to act differently in that if they are jumping from crown to crown, dozing out a guard line on the surface level has little impact. Marek says they are hoping this experiment will help them identify the differences in the way beetle stands burn, under what circumstances a fire will switch from a surface to "crown fire" and what fuel and weather conditions contribute to the creation of a crown fire.

The experiment, which will involve eleven plots of beetle kill trees ranging from 100 square meters, to 200 square meters. The crew has just completed measuring the amount of "forest fuel" in each plot and hopes to start the fire experiments next month if conditions get dry enough. Marek says it's important they get this one right "This will be the only free standing timber fire experiment in the world, we want to make sure we do a good job."

The results of the study will help determine improved fire fighting techniques, and safety measures for those battling the flames.
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