SAN FRANCISCO — After coming in $400 million over budget following last year’s busy fire season, the Forest Service is altering its approach and may let more fires burn instead of attacking every one.
The move, quietly made in a letter late last month by Forest Service Chief Tom Tidwell, brings the agency more in line with the National Parks Service and back to what it had done until last year. It also answers critics who said the agency wasted money and endangered firefighters by battling fires in remote areas that posed little or no danger to property or critical habitat.
Tidwell played down the change, saying it’s simply an ‘‘evolution of the science and the expertise’’ that has led to more emphasis on pre-fire planning and managed burns, which involve purposely setting fires to eliminate dead trees and other fuels that could help a wildfire quickly spread.
The more aggressive approach instituted last year was prompted by fears that fires left unchecked would devour large swaths of the drought-stricken West, Tidwell said.