While there are valid reasons to thin forests, including restoration of forest structure or health, wildlife enhancement or public safety, increased carbon sequestration is not one of them, scientists at Oregon State University said.
"Some researchers have suggested that various levels of tree removal are consistent with efforts to sequester carbon in forest biomass and reduce atmospheric carbon dioxide levels," John Campbell, research associate in the OSU Department of Forest Ecosystems and Society, said.
"That may make common sense, but it's based on unrealistic assumptions and not supported by the science."
Even in fire-prone forests, researchers said, it's necessary to treat about 10 locations to influence fire behavior in one, and there are large carbon losses associated with fuel treatment and tree removal and only modest savings in reducing the severity of fire.
"There is no doubt you can change fire behavior by managing fuels and there may be other reasons to do it," Mark Harmon, OSU professor of forest science, said.
"But the carbon does not just disappear, even if it's used for wood products or other purposes. We have to be honest about the carbon cost and consider it along with the other reasons for this type of forest management."