Mongabay: In the western U.S., few trees generally grow in higher altitudes than the whitebark pine (Pinus albicaulis). Providing shelter and food for bears, squirrels and birds, the whitebark pine ecosystems also help regulate water flow from snowmelt. But, according to a new study in the Proceedings of the National Academy of Sciences (PNAS), climate change has produced a novel threat for these high-altitude forests : mountain pine beetles (Dendroctonus ponderosae).
Mountain pine beetles have already...