Since the late 1970s, researchers have used tree rings and fire scars to reconstruct the fire history of an area and to understand how climate drives conflagrations. Tree growth rings vary in width with annual precipitation, providing a record of past climates. And when blazes burn a tree without killing it, they leave scars that can be dated along with the rings. Initially, researchers simply tried to understand how frequently fires had burned individual stands of trees, says Tom Swetnam, a fire ecologist at the University of Arizona in Tucson who is now based in New Mexico. Land-management agencies such as the US National Park Service and the US Forest Service had followed strict fire-suppression policies for decades, but they were beginning to recognize fire’s ecological benefits. The agencies wanted to know how fire had behaved historically, so they could use it as a tool to promote forest health...
Language: en
", language="en", issn="0028-0836", doi="10.1038/d41586-018-01686-y", url="http://dx.doi.org/10.1038/d41586-018-01686-y" }