Global warming threatens forests, study says

People don’t often think of forests as dying, but they do. A new study, reported in the journal Science today, found that forests in the Pacific Northwest are dying twice as fast as they were only 17 years ago. The researchers counted coniferous trees, mostly pines, firs and hemlocks, in 76 plots through the western United States. Mortality rates have increased for all types and ages of trees. California had the highest tree death rate, which leads to shifts in forest structure and function.