Trees stressed by global warming may not be able to survive simply by creeping up to higher elevations.
That’s the finding of a Department of Energy-funded experiment conducted by researchers from the University of California, University of Colorado and U.S. Geological Survey. The Denver Post reports the scientists planted Engelmann spruce and limber pine seeds on high-altitude plots above CU’s Mountain Research Station, then used heaters to simulate climate change. They found the seedling trees flourished only when extra water was added. They concluded that without additional rainfall, native trees won’t survive at higher elevations even when the temperature warms.