March of the beetles bodes ill for American forests
MEDICINE BOW NATIONAL FOREST, Wyoming - From the vantage point of an 80-foot (25 meter) tower rising above the trees, the Wyoming vista seems idyllic: snow-capped peaks in the distance give way to shimmering green spruce.
But this is a forest under siege. Among the green foliage of the healthy spruce are the orange-red needles of the sick and the dead, victims of a beetle infestation closely related to one that has already laid waste to millions of acres (hectares) of pine forest in North America.