Powers walks along plastic gutters designed to keep rain away from tree roots to simulate drought. Scientists here are studying the effects of sustained drought conditions on the tree species of the Southwest.
The droughts that have parched big regions of the country are killing forests.
In the arid Southwest, the body count is especially high. Besides trying to keep wildfires from burning up these desiccated forests, there's not much anyone can do. In fact, scientists are only now figuring out how drought affects trees.
Timmons and Springer work in the Apache-Sitgreaves National Forests, which were burned during last year's Wallow Fire. The largest fire in Arizona history, Wallow barreled through a half-million acres of forest.
Forests in the Southwest have become a fuel stockpile. A century of U.S. Forest Service policy of quashing all fires has allowed forests to become overgrown, and now a warming climate is making the problem worse.
Scientists are trying to defuse these green time bombs. Is it too late?
Jorge Castro, a visiting professor of ecology from Spain, sips water in the shade of a burnt tree in New Mexico's Bandelier Wilderness area, adjacent to the Bandelier National Monument. This site was devastated by last year's Las Conchas fire.
Fire scientists are calling it "the new normal": a time of fires so big and hot that no one can remember anything like it.
One of the scientists who coined that term is Craig Allen. I drive with him to New Mexico's Bandelier National Monument, where he works for the U.S. Geological Survey. We take a dirt road up into the Jemez Mountains, into a landscape of black poles as far as you can see.