Image of the Day: (Not Enough) Snow Falling on Cedars

Researchers from the U.S. Forest Service may have zeroed in on the causes of a longtime mystery in Alaska's Panhandle: the reason why hundreds of thousands of yellow cedar trees have perished during the past century. According to the Associated Press, the trees, which can live for up to 1,000 years, have roots that are vulnerable to freezing if there is a lack of snow on the ground. Snow cover insulates the soil, keeping it warmer than bare ground is during the winter.

“The cause of tree death, called yellow-cedar decline, is now known to be a form of root freezing that occurs during cold weather in late winter and early spring, but only when snow is not present on the ground,” said Forest Service scientist Paul Hennon, co-lead author of a paper recently published in the February issue of the journal BioScience, in a press release

The trouble is that snowfall patterns have changed in this region, especially during the past few decades. These shifts may be related to global warming, according to the study. In areas where there has been a decrease in snow cover, frozen roots have killed yellow cedar trees across nearly a half-million acres in southeast Alaska, and more than 100,000 acres in British Columbia.

Photo Credit: Paul Hennon/AP