Bill Jennings: Beware of tree wells, a silent killer on the slopes

Getting caught in an avalanche is a terrifying way to get killed while skiing or riding. But unless you spend most of your time in the backcountry, it’s more likely you could meet your demise from a threat less spectacular, but terrifying just the same.

Last Wednesday, an email showed up in my inbox from the Inland Northwest Ski Association. INSA wanted to highlight a commonly overlooked risk of our recent epic snowfalls: tree wells. I filed the topic in my brain as a potentially actionable column idea.

Tree wells aren’t exactly top of mind as snow hazards go because you don’t hear about people dying in them as often as news about killer avalanches. But both cause a nearly equal amount of total deaths each season. Two days after I received the INSA email, a skier and a snowboarder died in tree wells at Mt. Bachelor in central Oregon on the same day.

A Mt. Bachelor spokesperson said it had been 16 years since a tree well claimed someone there. In that time span, the resort logged about 8 million visits a year. Those are pretty long odds for dying in a tree well. It’s easy to dismiss the risk and believe it couldn’t happen to you. That may have been the mindset of Alfonso Braun, 24, of Bend, and Nicole Panet-Raymon, 19, of Eugene.

A tree well forms when a tree’s limbs shelter its trunk from snowfall. Look at evergreens in summer and you will see how high a trunk can extend before limbs branch out—often about as high as the snow piles up in winter. The summit depth at 49 Degrees North earlier this week, a hill renowned for tree skiing, was more than 11 feet.

As snow accumulates around the tree, a parabolic void is created in deep powder around its base. Water vapor rising from the base of the trunk gives the snow a sand-like consistency. A tree well resembles the trap of an ant lion, a fearsome looking insect that lurks in a funnel of sand, waiting for prey to tumble inside. Skiers and riders occasionally fall into such a trap.

Tree wells are deadly because someone caught unawares usually falls into the trap headfirst. Stuck upside down, it is virtually impossible for the victim to extricate their feet from the bindings of their skis or board. If he or she is alone, there’s a good chance of not emerging alive. Should that happen, the official cause of death would be coldly noted as “snow immersion suffocation.”

The Pacific Northwest Ski Area Association (PNSSA) issues a brochure on tree well safety. No. 1 on its prevention list is to avoid deep snow and tree areas. As for my friends and myself, Hell might as well freeze over. No. 2 is always keep your partner in sight (see previous reference).

I could actually adopt some items from No. 3: ski and ride defensively. For example, trapped inverted in a tree well, hands caught in pole straps can be a matter of life or death. Letting them flap in the wind is easy enough to do. On the other hand, trying not to go inverted as you fall into a tree well may not be so easy.

Your last line of defense, No. 4, is “fight to survive.” In this case, “fight” does not mean “struggle.” Doing so will sink you deeper and immobilize you further. If you’ve had the foresight to forgo pole straps, you may be able to create a breathing space around your face. Finally, stay calm. Chilling out will conserve air and improve your chance of being found before you suffocate. Good luck with that.

The morning of the dual Mt. Bachelor tragedy, the resort issued a warning about “new low-density snow,” and “tree wells and snow immersion hazards.” Its simple advice was to “always ski or ride with a buddy in eyesight if you’re headed off-trail.”

Greedy for untracked powder, running with a pack of slobbering hounds, I probably would have ignored that advice. But maybe last week’s grim reminder of the risk could save my life, or yours, someday.