Roger Marolt: Mostly guessing about wildfires
During hot, dry summers, wildfire danger makes us hold our breath
Everything I know about wildfires I could write in a 750-word column, so I thought I might as well do it since we should all be thinking more about this.
The Coal Seam Fire in June of 2002 west of Glenwood Springs left an indelible impression. I think of it every time I pass through the canyon there. Thankfully it did not take lives like the Storm King Mountain Fire did eight years earlier in the same area. Fourteen firefighters tragically lost their lives battling that blaze formally known as the South Canyon Fire.
The terrifying thing about the Coal Seam Fire had to do with my new awareness of the incredible potential of a wildfire. That blaze ended up jumping both the Colorado River and I-70 to continue its destructive path on the other side of the valley. Recalling this as I survey the fuel-free boundary between my neighborhood and the adjacent hillside loaded with juniper and sagebrush makes me feel vulnerable.
That fire was started by an underground coal seam that had been smoldering for years, possibly lit by a lightning strike before I was born. I have also seen fires started by rubbing two pieces of wood together. That Boy Scout technique is not a myth. The point is that it doesn’t take a raging campfire built in a dry pine needle bed during a howling gale to start a forest fire. It only takes a spark. A cigarette butt thrown out the car window in the tinder-dry West these days might as well be a flamethrower. Fireworks? You have to be kidding!
It might also be important to know that wildfires generally move much faster uphill than downhill. This is the opposite of what humans can do covering the same topographies. Anyone who has hiked and skied Highland Bowl can understand why this is so. The northwest side of the ridge on your right as you hike up is swept clean of snow by prevailing winds that hit the slope, compress, and accelerate up the side of the mountain.
As soon as it crests the ridge, the air mass expands and immediately slows. That lee side of the mountain is oftentimes calm even as 50 mph winds batter the windward side mere feet away. It’s why the skiing is so nice and cornices so large on the lee side. Either way, if you find yourself having to outrun a fire, you have already made a serious mistake in judgment. Keep that in mind when you put an emergency escape plan in place.
Once I supervised a middle school science fair project for one of my kids. They wanted to find out which local wood burned hottest. They hypothesized that sappy pine or dense scrub oak would produce the highest temperatures. The test didn’t prove that. Surprisingly, dry aspen was the hottest. We concluded this was because there is more oxygen in the less-dense dried aspen than the other woods tested.
This test of scientific method not withstanding, I have found that it is nearly impossible to burn green aspen, cottonwood and willow woods. As kids, my great uncle Steve carved the ends of willow sprigs sharp and we used them to roast hot dogs over an open fire. I don’t recall ever seeing one of those sticks so much as singed afterward. Much the same, I have seen great campfires ruined by novice fire pit attendees throwing logs of green aspen on it. The same can be observed with wet cottonwood logs. They literally steam when thrown on a fire.
I cannot recall ever seeing a burn scar running through a hillside of aspen trees. I have seen aspen split by lightning that remained greenish-tan color in their trunks with no sign of singeing in their bark. It makes me wonder if aspen, cottonwood and willow trees planted around the perimeter of a property could act as a firewall of sorts. They grow much taller than scrub oak or sagebrush, so it might be possible that their branches could knock down sparks and floating embers before they reach cedar roof shakes. It kind of makes sense, but I’ve never heard this given as sound wildfire prevention advice. I would like to know what the experts think.
I cannot confirm or deny old stories about trees that caught fire from dry roots protruding into a campfire pit and then burning underground to the base of the tree, eventually causing it to ignite. My guess is this is a legit threat. Take wildfires seriously!
Roger Marolt is learning to hold his breath longer during these hot, dry summers. Email him at firstname.lastname@example.org.