If you want to know about a fire that burned in the Sangre de Cristo Mountains a thousand years ago, chances are that a bristlecone pine tree that can tell you all about it.
“Here in the Southwest, New Mexico and Arizona, pine forests are growing in dry, rocky landscape and they get to be really old – up to 1,000 years old lying on the ground,” said Tom Swetnam, former director of the Laboratory of Tree-Ring Research at the University of Arizona.
“There are probably some living trees, bristlecones up in the Sangre de Cristos, that are a thousand years old.” Swetnam is part of a team of tree-ring researchers working on a long-term study of fire history in the forests near Taos in an effort to chart a course for better fire management in the future.
The idea is to use thinning to restore forests to some semblance of the shape they were in when fires burned naturally, before people started messing with things better left alone.
The trees remember how it used to be.
Using chain saws, researchers cut cross sections out of dead trees or employ a coring process to extract pencil-shaped sections from living trees.
Then, by analyzing burn scars, the cooked resin between tree rings, they can determine when a fire burned, how big it burned and how hot it burned. Even if that fire blazed hundreds of years before Smokey Bear was a cub in the Capitan Mountains.