Mortality rate for old growth trees doubles

Think Progress - The Rocky Mountain forests that traverse the West are under unprecedented danger from climate-related impacts according to a new report from the Union of Concerned Scientists and the Rocky Mountain Climate Organization. The Rockies include national parks like Yellowstone, Grand Teton, and Glacier National Park, and are facing a “triple assault — tree-killing insects, wildfires, and heat and drought — that could fundamentally alter these forests as we know them.”

According to the report, titled “Rocky Mountain Forests at Risk,” many western trees are dying from “no obvious cause” like the bark beetle epidemic or increasing threat of wildfire, with scientists suggesting that these deaths are due simply to the hotter and drier conditions associated with climate change. The mortality rate for old-growth trees in undisturbed forests has doubled recently, with a sharp increase in recent years, and there’s been no compensating increase in the number of seedlings.