Wildfires: Forest regeneration stymied by hot crown fires

Wildfires that have burned across almost 750,000 acres in Arizona are doing more than turning forests into charred stumps. Researchers with Northern Arizona University say the fires, burning in unnaturally dense stands of ponderosa pine, are turning the forests from carbon sinks into net carbon producers — and, the fires have burned so hot that they aren’t finding many signs of regeneration. Mike Stoddard, a forest ecologist with NAU’s Ecological Restoration Institute, has been looking for a sign, any sign, of ponderosa pine seedlings 15 years after the 1996 Hochderffer Fire, a crown fire that burned hot through 16,000 acres west of the San Francisco Peaks, near Flagstaff. “These large fires are devastating our forests,” Stoddard said. “We’re concerned that ponderosa pine is not regenerating after these wildfire events.” Crown fires burn into the canopies and treetops or crowns of the trees — massive, intense crown fires, such as the Wallow Fire in eastern Arizona, are not natural in the ponderosa pine forest. Naturally occurring ponderosa pine fires burn along the ground, or base, of the trees...more