Expert: climate change, giant wildfires pose great risk to Arizona's forests
According to those who study the wildfires that have devastated Arizona, the state remains in an era of catastrophic forest fires.
Before forests became so thick with Ponderosa pine, small fires would burn away the brush, which thins out the forests. Now, however, scientists say the size of our recent fires, along with climate change, pose the greatest threat ever to forests in Arizona.
Recent fires such as the Goodwin Fire near Mayer have left some parts of the state smoldering. Meanwhile, the Shultz Fire, which burned near Flagstaff in 2010, left fire and flooding scars on the landscape that is still visible to this day.
"In the Shultz Fire, when we had such devastating flooding -- there were rains that were about an inch in 10 minutes -- this was a 300, 400 year event, and when you have that much rain falling on a bare slope and hydro water resistant fires, that stuff comes down in a hurry," said Wally Covington, Executive Director of the Ecological Restoration Institute at Northern Arizona University.
Another fire that burned near Flagstaff was the Radio Fire. That fire burnt almost 5,000 acres of land. The landscape today at the fire site remains bleak, 40 years after the fire. Boulders are still stained by the slurry dropped by firefighting aircraft, but some Ponderosa pines have returned, if only in areas where the soil has not washed away.
"Back in '77, that was a big, big fire," said Covington."Of course, now we wish we have 5,000 acre fires."
Covington was in Flagstaff in 1977, when the Radio Fire swept over Mount Elden. Covington said people today will never see complete recovery in their lifetimes, or our children's, for their matter.
"When you lose the soil down to bare parent material, the time period for recovery is 100,000 years, 150,000 years," said Covington.
Covington is in charge of a program to restore Ponderosa pine forests to what it was like before humanity.
Evidence shows that it was actually Euro-American settlement that disrupted the natural fire regime through heavy livestock grazing, timber harvesting, and fire suppression--not simply humans in the general sense. Native Americans living here centuries prior to the arrival of Euro-Americans (1880s) had actually been living with and managing fire in ponderosa pine forests for generations. It's a small point, but one that is important to make when discussing the deteriorating health of our forests over the past 120 years.
Aggressive firefighting efforts in the middle of the 19th century allowed the pines to grow so thick, that today's fires become catastrophic in a hurry.
"So it went from 20 to 30 trees per acre to a thousand tress per acre," said Covington.
With the forecast severe weather associated with climate change and global warming, Covington expects the situation will only get worse.
"During the past 100 million years, we have had big swings in climate, with carbon dioxide concentrations ten times what they are today, and these forests have survived through that," said Covington. "They have never had to confront the lack of self regulating frequent fires and climate change. This is where we are in a very critical condition for Ponderosa pine."