LAKE ARROWHEAD -- As flames ravage surrounding communities, this resort town high in the San Bernardino Mountains emerged largely unscathed, an island in a sea of destruction.
The credit for that isolated victory, federal officials say, should go to firefighting tactics, shifting winds and favorable terrain -- and a sometimes controversial U.S. Forest Service effort to eliminate the tinder that fuels forest fires.
Since 2002, the Forest Service has removed millions of trees, thinned brush and cut low-hanging branches, creating fuel breaks around almost 80% of the community. Fires don't spread quickly or easily through such areas, instead burning lower to the ground and with less intensity.
"The fuel breaks saved Lake Arrowhead," said Randall Clauson, the Forest Service's division chief for the San Bernardino National Forest and incident commander earlier this week on the two biggest wildfires still burning in the mountains.
He said he believes that, without the breaks, "the fire would have run right through Lake Arrowhead and gone to Highway 18, cutting off the evacuation route and probably resulting in the loss of hundreds of lives."
But not everyone was convinced that forest-thinning itself played such a pivotal role.
"Thinning and cleanup of surface fuels really does help," said Ken Larson, a fire behavior analyst with the Forest Service, stationed at the fire command post in the San Bernardino Mountains. "But there are many variables at play. Even that may not save structures in the face of extreme winds and extreme conditions."
Still, evidence was dramatic in the thinned forest areas. In one cluster of Lake Arrowhead neighborhoods protected by fuel breaks, only a few stumps were burning and no trees were lost. Hundreds of surrounding homes were untouched.
Some of the worst-hit areas like Running Springs don't have fuel breaks. Just 20% of Big Bear is protected by breaks, fire officials said.
The Forest Service decided that Lake Arrowhead would be first in line for the fuel breaks because it had suffered worst from the bark beetle infestation and drought that killed 90% of its pine trees, turning them into enormous fire hazards.
"We have been doing it like triage," Clauson said. "We started here so we got the most done here."
The work is painstaking, expensive and controversial. Clauson has a budget of $17 million a year to create fuel breaks in the forest and has so far completed 25,000 acres. The goal is 100,000 acres. He still runs into people who object to cutting trees, suspecting it of being clandestine logging.
To gain public acceptance, Clauson spent a year holding meetings, sometimes attending three a week, where he pushed the idea and urged private landowners to thin their trees.
"This has been the first test of this magnitude and I think it has proven its effectiveness," he said.
And yet there is only so much the Forest Service can do. Lake Arrowhead didn't escape unscathed. In Grass Valley, an upscale part of the town about a mile from Lake Arrowhead, more than 100 homes were destroyed. Many had been surrounded by tall trees and lush vegetation left uncleared by the homeowners.
There were scenes of total devastation -- lakeside homes reduced to their foundations, torched cars and, in one house, only a pair of smudged lawn jockeys survived. Power lines littered the ground or hung perilously overhead.
"We can spend $100 million to put fuel breaks around every town up here but if individuals don't take responsibility for their land I can't save them," Clauson said.
Meanwhile, with winds diminishing and humidity rising, firefighters Wednesday stepped up their offensive against the two major fires in the Lake Arrowhead area, shifting their emphasis from protecting structures to encircling the blazes.
Helicopters, air tankers, earth-moving equipment and firefighters -- freed from other Southern California fires that had become less threatening -- were redeployed to San Bernardino Mountains communities including Running Springs and Grass Valley.
"We would like the Grass Valley fire contained and out of our hair; we're going to put a lasso around it," said Pat Farrell, an operations manager for firefighters headquartered at Rim of the World High School along California 18 between Lake Arrowhead and Running Springs.
Early Wednesday, fire authorities came under intense criticism from some residents of Green Valley Lake, about 10miles to the east, who accused them of abruptly pulling firefighters out of the community Monday night.
By late Wednesday, firefighters had contained 30% of the Grass Valley blaze, where 113 homes have been destroyed and 6,000 remained threatened.
Farrell said the Slide fire, which has scorched 10,800 acres near Running Springs, was "more complex and moving in different directions." He hopes to focus on that fire after subduing the Grass Valley blaze. The toll of the Slide fire by late Wednesday was 200 homes and three other structures destroyed and 10,000 residences still threatened.
Farrell said firefighters would keep protecting structures, "but the big focus today is on perimeter control."
Gearing up for the assault on the Slide fire, crews rushed Wednesday afternoon to set up a base camp for as many as 3,000 firefighters at the Snow Valley Ski Resort about 20 miles east of Lake Arrowhead.
As workers were building sleeping quarters, shower stalls, kitchens and communication centers for new arrivals from as far away as Utah and Idaho, the Slide fire raced through insect-ravaged and drought-stricken forests, sending up clouds of smoke so thick that air tankers were unable to attack at times.
The fire spread across a vast swath of mountainous terrain, occasionally making unexpected runs up side canyons to California 18 where firefighters fought back with hoes and shovels.
In the meantime, utility crews were roaming the mountains securing power lines and turning off gas mains. The Rim of the World High School became a bustling staging grounds for earth movers, fire engines and hand crews streaming in all day from fires elsewhere.
Times staff writers Francisco Vara-Orta and Stuart Silverstein contributed to this report.