Impact of forest thinning on wildfires creates divisions

Firefighters and numerous studies credit forest thinning projects with helping to save communities like those near Lake Tahoe

SACRAMENTO, Calif. -- Firefighters and numerous studies credit intensive forest thinning projects with helping save communities like those recently threatened near Lake Tahoe in California and Nevada, but dissent from some environmental advocacy groups is roiling the scientific community.

States in the U.S. West and the federal government each year thin thousands of acres of dense timber and carve broad swaths through the forest near remote communities, all designed to slow the spread of massive wildfires.

The projects aim to return overgrown forests to the way they were more than a century ago, before land managers began reflexively extinguishing every wildfire as soon as possible.

Efforts now include using fire to fight fire, with fires deliberately set in the cooler, wetter months to burn out dangerous fuels, or backfires set in the path of encroaching wildfires. Forest managers credit such burns with helping protect the Giant Forest in Sequoia National Park.