Iconic Forests Reaching Climate Tipping Points in American West

Ponderosa pine and Douglas fir forests are struggling to regrow after wildfires in parts of the West as temperatures rise and the air and soil become drier.

Climate change in the American West may be crossing an ominous threshold, making parts of the region inhospitable for some native pine and fir forests to regrow after wildfires, new research suggests.

As temperatures rise, the hotter, drier air and drier soil conditions are increasingly unsuitable for young Douglas firs and ponderosa pines to take root and thrive in some of the region's low-elevation forests, scientists write in a study published Monday in the Proceedings of the National Academy of Sciences.  Wildfires in these areas could lead to abrupt ecosystem changes, from forest to non-forest, that would otherwise take decades to centuries, the study says.

"Once a certain threshold was crossed, then the probability of tree establishment decreased rapidly," said Kimberley Davis, a researcher at the University of Montana and lead author of the study.  "The climate conditions are just a lot less suitable for regeneration."

The two iconic species are important to both the region's forest ecology and its economy, particularly its timber industry.

Read more at Iconic Forests Reaching Climate Tipping Points in American West, Study Finds