 When these trees die and fall on the ground, they become thousand-hour fuels, and they'll burn for a thousand hours when they catch fire. But once you've got dense vegetation in taller trees and low vegetation underneath, it can crown fire, and that's what's the most dangerous. That's what we lose the greatest number of trees. And how did McKenzie develop his powers of observation? Practice. Taking one area of forest at a time and spending time seeing and creating