Christopher Roos Publishes Major Article in PNAS

Aug. 20, 2025 — Professor Christopher I. Roos recently led the publication of a seminal fire history paper in the Proceedings of the National Academy of Sciences. Roos and a team of scientists, including members of the White Mountain Apache and San Carlos Apache tribes, leveraged a large dataset of thousands of fire-scarred trees across Arizona and New Mexico to demonstrate that Ndee (Western Apache) people managed fire across their ~19,000 square mile homeland in central Arizona. Tree-ring analysis revealed that fires on Ndee homelands were more frequent, smaller, occurred disproportionately in late April and May, and ultimately buffered the impacts of climate when compared to the rest of the region. Roos and colleagues argued that the centuries of Ndee fire stewardship could be a model for fire management.