Yellow-cedar are dying in Alaska

Terra Daily via SPX: Yellow-cedar, a culturally and economically valuable tree in southeastern Alaska and adjacent parts of British Columbia, has been dying off across large expanses of these areas for the past 100 years. But no one could say why-until now.

"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," explains Pacific Northwest Research Station scientist Paul Hennon, co-lead of a synthesis paper recently published in the February issue of the journal BioScience.

"When present, snow protects the fine, shallow roots from extreme soil temperatures. The shallow rooting of yellow-cedar, early spring growth, and its unique vulnerability to freezing injury also contribute to this problem."

Yellow-cedar decline affects about 60 to 70 percent of trees in forests covering 600,000 acres in Alaska and British Columbia. The paper, "Shifting Climate, Altered Niche, and a Dynamic Conservation Strategy for Yellow-Cedar in the North Pacific Coastal Rainforest," summarizes 30 years of research and offers a framework for a conservation strategy for yellow-cedar in Alaska....

Yellow-cedar cones and foliage. Behind are Subalpine Fir trees. Shot by Walter Siegmund (talk), Wikimedia Commons, under the Creative Commons Attribution-Share Alike 3.0 Unported license