The balsam woolly adelgid, a tiny nonnative flightless insect, is spreading across the American West killing subalpine fir in northern Utah's recreation-heavy mountain ranges and canyons. Rsearchers ...

Imagine yourself walking quietly through a high-elevation subalpine forest. You feel immersed in shady stillness while enveloped by a fresh scent of pine, spruce and fir. You gaze out at the trees ...

A tagged subalpine fir tree, one of more than 5,000 marked trees monitored as part of this 37-year-long study in the Colorado subalpine forest on Niwot Ridge, west of Boulder. Disclaimer: AAAS and ...

An aerial survey conducted this past summer by the U.S. Forest Service and the Oregon Department of Forestry found more than 1 million acres with dead or dying fir trees in Oregon, the largest amount ...

A nonnative tree-killing insect is invading northern Utah, attacking subalpine fir and potentially triggering yet another die-off of the region’s long-stressed conifer forests. Introduced from central ...