After a quick hike off a steep dirt road, forest ecologist Marin Chambers stands surrounded by grasses, shrubs and blackened bare trees. This is part of where the Hayman fire — until last month, Colorado's largest in recorded history — burned northwest of Colorado Springs back in 2002. The ground is dry, crunching underfoot.

"What we're seeing is a very large high-severity burn patch, where the vast majority of the trees have died," says Chambers, with the Colorado Forest Restoration Institute at Colorado State University.

These 18-square miles burned hot and fast in a single day, driven by how dense the forest was because of past fire suppression, high winds and extreme drought. Now, nearly two decades later, something you'd normally see after a wildfire is missing: new trees.