In fact, skiers and snowboarders are at high risk of dying from avalanches caused by small snow fractures that sweep between trees, said Dale Atkins, president of the American Avalanche Association.

"Once an avalanche fractures and starts to move, it very easily causes the snow to move through the trees and around the trees," said Atkins, a veteran avalanche forecaster from Colorado who presented some of his findings at the International Snow Science Workshop this week in Anchorage

"Once the snow starts moving, it's literally moving as fast as a speeding car," he added.

Since even small avalanches travel so fast that skiers and snowboarders swept by sliding snow into trees have a risk of being killed similar to that of pedestrians who are hit by speeding cars, he said.

Atkins analyzed 160 U.S. avalanche deaths over the past five years. Forty-three percent involved skiers and snowboarders. Of those, about a third died when they hit trees, according to his analysis.

Winter sports enthusiasts who get caught in a snow slide in the woods should not expect to save themselves by getting an arm around a tree trunk. Avalanche victims are swept downhill too fast to grab onto trees, Atkins said.

The only tree-covered areas that do provide protection from avalanches, he said, are those where the trees are too close together to allow skiers to squeeze around them - areas not attractive to skiers or snowboarders, he conceded.

"If you can't ski through the trees, you're probably safe," he said. "It's not a whole lot of fun." (Editing by Cynthia Johnston)

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