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Experts Discuss How To Preserve Arizona's Forests
Too little water and too many trees is a combination leading to mega-fires.
Arizona's forest experts gathered to discuss solutions to the state's forest and watershed problems. The two-day Finding Solutions Conference, hosted by Salt River Project in Scottsdale focused on investment strategies to fund forest preservation. Northern Arizona University’s Wally Covington says catastrophic wildfires are more frequent because of overcrowding of vegetation in forests.
“The main driver of the forest health problems that we have got now is where these forests were once kept open by frequent fires, once we put those fires out then a lot of trees became established that was far beyond the capacity of the land," Covington said.
These frequent forest fires used to burn parts of forests, but with the overpopulation of trees the wildfires are now burning several hundred thousand acres.
"We call those mega-fires and that is what the four forest restoration initiative and other initiatives that are growing around the country are that is to try to remove those excess young trees restore the health of the old trees and reintroduce natural fire," Covington said.
The Four Forest Restoration Initiative is a long term program to restore 2.4 million acres of Arizona forest ecosystems to their natural levels. When forests ecosystems fall out of balance it can lead to catastrophic wildfires, insect infestations, drought and flooding. Covington says the way to combat overcrowding is to thin the forest, but the challenge is burning only sections of the forest, without the fire getting out of control.
“When the forest are this thick there is no safe way to burn them hot enough to kill some of the trees and leave other trees, what happens is it’s an all or nothing kind of game typically. The way we remove those now is to mechanically thin them that means cut the young trees not the old trees. Cut the young trees down and remove them. The problem is that is very expensive," Covington said.
Covington says treatments can cost between $500 and $2,000 per acre. Money the forest service does not have. Covington says he wants to find a way to use the removed trees to help pay for the trimming treatments. Arizona State Forester Scott Hunt says the states watershed is directly related to the forest health.
“Our forests are critical to our water yield and when our forests have to many trees they are absorbing a lot of the water that is not flowing downstream and into our watersheds," said Hunt.
Local, federal and private sector groups are looking for ways to pay for these treatments.