Climate is changing too quickly for the Sierra Nevada’s ‘zombie forests’

Some of the tall, stately trees that have grown up in California’s Sierra Nevada are no longer compatible with the climate they live in, new research has shown.

Hotter, drier conditions driven by climate change in the mountain range have made certain regions once hospitable to conifers — such as sequoia, ponderosa pine and Douglas fir — an environmental mismatch for the cone-bearing trees.

"They were exactly where we expected them to be, kind of along the lower-elevation, warmer and drier edges of the conifer forests in the Sierras," Avery Hill, who worked on the study as a graduate student at Stanford University, told NPR.

Although there are conifers in those areas now, Hill and other researchers suggested that as the trees die out, they'll be replaced with other types of vegetation better suited to the environmental conditions.

The team estimated that about 20% of all Sierra Nevada conifer trees in California are no longer compatible with the climate around them and are in danger of disappearing. They dubbed these trees "zombie forests."