In June of 2002, nearly half a million acres burned in the Arizona high country. At the time, the Rodeo-Chediski Fire was the largest wildfire in the state’s history. There was too much fuel in the forest, a buildup that began more than a century ago. Enough people saw the record-breaking fire and agreed that something needed to be done to prevent the next big fire.
But correcting mistakes of the past is often tougher than it sounds. Almost two decades later, those involved in responding to the Rodeo-Chediski say they’re still learning what it will take to get ahead of wildfires, and the effects they have on headwater forests.
“I think the first thing to recognize is that the southwest and California are built to burn,” said fire historian Stephen Pyne, author of “Fire in America.”
“We get lots of dry lightning,” Pyne said. “We’re the epicenter for lightning-caused fires in the United States.” Ponderosa forests evolved with fire. Small, naturally-caused fires would burn grasses, small trees and brush, but leave the big trees with their thick bark, high branches and stout trunks, still standing. Then decades of overgrazing and fire suppression removed grasses and allowed small trees to grow.
Without fire to burn off the excess, the forest filled with all sizes of fuel. By the time foresters figured out the problem, big, unruly fires were on the way.
Conservationists, foresters, rural residents, ranchers and public lands advocates began to take an active interest in the role of fire in ponderosa forests. Conservationists worried about ecosystems. Ranchers worried about their homes. Leaders at the Salt River Project, which provides power and water for the Phoenix metro area through a series of dams, worried about the impact of fire on watersheds.
Burn scars can send excess ash, sediment and toxic compounds into water supplies for municipal and agricultural users for miles downstream. They can also reshape flood zones and increase risks of mudslides...
MORE
No comments:
Post a Comment