Death Rates Have Doubled, Researchers Find By Juliet Eilperin, Washington Post Staff Writer 
The death rates of trees in western U.S. forests have doubled over the past two to three decades, driven in large part by warmer temperatures and water scarcity linked to climate change, a new study spearheaded by the U.S. Geological Survey has found. The findings, published today in the online journal Science Express, examined changes in 76 long-term forest plots in three broad regions across the West, and found similar shifts regardless of the areas’ elevation, fire history, dominant species and tree sizes. It is the largest research project based on old-growth forests in North America. Nathan L. Stephenson, one of the lead authors, said summers are getting longer and hotter in the West, subjecting trees to greater stress from droughts and attacks by insect infestations, all factors that contribute to greater tree die-offs. "It’s very likely that mortality rates will continue to rise," said Stephenson, a scientist at the Geological Survey’s Western Ecological Research Center, adding that the death of older trees is rapidly exceeding the growth of new ones, akin to a town where deaths of old people are outpacing the number of babies being born. "If you saw that going on in your home town, you’d be concerned."
Trees in Western U.S. Forests Dying Due to Climate Change
