The Jemez Mountains of Northern New Mexico are no stranger to fire. But the wildfires that have burned through the mountain range in the last 30 years were unprecedented. They were uncharacteristically severe and damaging compared to the prior five centuries, according to a new study.
The study found that since the 1996 Dome Fire, wildfires have burned the same areas over and over again, causing lasting ecosystem transformations. Ponderosa pine and other species found in dry-conifer forests were decimated. The severely and repeatedly burned soil is now choked with grasses and shrubs like oak, locust, and aspen. At the rate of current wildfire frequency, the researchers predict that only half of the dry-conifer forests of the Jemez Mountains will still be alive in the next 30 years.
For centuries, according to tree ring studies, the Jemez Mountain forests were accustomed to frequent, low-severity fires that cleaned out woody debris and reduced tree density. The trees that remained were adapted to these fires – large with thick bark and raised crowns. 20th century logging removed most of these trees, and the ones that grew in their place aren’t adapted to what is happening now.
“Over my lifetime I’ve watched more and more fires eat more and more holes into the forest” said Andreas P. Wion, lead author of the study. “New Mexico is ground zero for many of these changes – the Jemez Mountains especially so. More forests will unravel in our lifetimes, likely in unpredictable and unexpected directions.”
This study, published in the Proceedings of the National Academy of Sciences, adds to the body of research examining the causes and consequences of extreme wildfire behavior” in Western forests.
Wion said given prior research, in some ways researchers on this study weren’t surprised by their findings. “What was surprising was the strength of this result,” Wion said. “Across thousands of simulations, there was absolutely no way that fires like Las Conchas could have occurred anywhere in the Jemez Mountains for the past 500 years. That was a shocking realization.” Las Conchas fire burned 44,000 acres in a matter of hours in 2011.
Wion, now a spatial analyst in residence at the New Mexico Forest and Watershed Restoration Institute, plans to continue studying the impact of conditions on Southwest forests. “I am asking this question at a larger spatial scale, quantifying where, when, and why forests may be burning at similarly extreme severity in the southwest.”
But importantly – he says, “Our future isn’t predetermined. Despite dire predictions of forest loss, active forest management, ecological restoration, and land stewardship can indeed restore the patterns and processes that help forests better withstand and recover from the next fire.”
Study: Recent high-severity wildfires in a dry-conifer landscape are unprecedented over five centuries and foretell future forest loss.
Authors: Andreas P Wion, Jens T. Stevens, Jonathan D. Coop and Ellis Q Margolis
Study mentioned in National Geographic article How Wildfire is Erasing the Forests of the American West