Houses sitting on cleared spaces with irrigated plants, fire-resistant roofs, metal fences and other fire-safe features were spared while their neighbors' homes burned.

"A lot of homeowner inaction went into creating this urban fire," said John Pickett, Tahoe Region Chapter Coordinator for the Nevada Fire Safe Council, as he drove through burned neighborhoods Tuesday.

On Cone Road, a house with gravel spread around the foundation, cleared brush and a metal fence survived unscathed while the one across the street was burned to the foundation.

And on Boulder Mountain Drive, a house with a stone patio swept free of pine needles and sprinklers placed on the roof was still standing. All of its neighbors were gone.

"If you look at how many small flammable sticks there were throughout here, you can tell they weren't dealing with their defensible space; there's tons of ground fuel," said Stewart McMorrow, forest fuels manager for the North Tahoe Fire Protection District.

Julie Regan, spokeswoman for the Tahoe Regional Planning Agency, said the majority of the 1,300 properties in the area affected by the fire did not have "defensible space," a cleared area around the home.

Not all of these had homes built on them, and not all were in the direct path of the flames. In all, 275 structures had burned as of Tuesday afternoon, 200 of them houses, according to the U.S. Forest Service.

"It's obvious we need to do more to educate the community," Regan said.

The condition of national forest land adjacent to the neighborhoods played a role, too. Streets next to land thinned of underbrush and small trees by the U.S. Forest Service fared better than those next to more overgrown areas, Pickett said.

"We've spent all day trying to get our brains around what happened here," Pickett said. "If the forest adjacent to the homes was thinned, then the homes stood a chance. If it wasn't thinned, they didn't stand a chance."

The U.S. Forest Service released a map Monday showing that most of the national forest near burned neighborhoods had been thinned to improve fire safety.

Since 2003, the Forest Service has thinned almost 15,000 acres around Lake Tahoe, said Matt Mathes, spokesman for the service's Pacific Southwest regional office. It plans to thin another 42,000 acres in the next decade.

But Pickett said his tour of the burned neighborhoods Tuesday revealed plenty of thickly wooded sections where crowds of small trees and underbrush created fuel ladders for the fire to race to the tops of the big trees and jump hundreds of feet.

On Lookout Point Circle, where all the houses were burned to the ground, the adjacent forest was "grossly overstocked," he said.

Meanwhile, the fire has exposed an undercurrent of distrust between residents and the Tahoe Regional Planning Agency, or TRPA, which regulates building in the Lake Tahoe basin.

In order to remove a tree with a diameter of more than 6 inches, homeowners need a permit. But many are reluctant to apply because they think TRPA will inspect their properties and find a reason to fine them, some fire officials say.

Part of TRPA's mission is to maintain Tahoe's forest canopy.

"People are scared to death to do anything on their own property because they are afraid of retribution; it's created this huge paralysis," said Jessica Mahnken, defensible space coordinator with the Lake Valley Fire Protection District.

Pickett agreed that people are hesitant to apply for a tree removal permit. But he said that's mostly because they don't understand that the process is now more user-friendly.

In the area of the Angora fire, for instance, tree removal permits to create defensible space are now issued by the Lake Valley Fire Protection District, which acts on behalf of TRPA. The agency has similar agreements with five of the seven fire districts in the Tahoe basin.

Regan said TRPA actively encourages people to remove small trees and brush around their property. It's when people try to cut down large trees to improve their views that they run into problems, she said. In order to do that, they must obtain a permit from TRPA directly.

Mahnken of the Lake Valley Fire Protection District said she's had difficulty getting homeowners interested in taking steps to improve their fire safety.

Earlier this year, after receiving a grant to help homeowners create defensible space, she went door to door in the area that burned this week. She also sent out 400 letters.

Ten people showed up for the subsequent meeting.

After touring the fire zone Tuesday, she said some homeowners who had cleared a protective zone around their homes lost them anyway because their neighbors didn't bother.

"You're only as safe as your neighbor," she said.

She noted that state law says that rural property owners should maintain 100 feet of defensible space around their homes. Compliance is voluntary, however.

"Do I see it becoming mandatory?" she said. "Potentially. That's something I could see happening."

Regan, the TRPA spokeswoman, said her agency has never sought to enforce a 100-foot zone of defensible space, but has recommended that homeowners clear 30 feet around their houses. "I know the state law is 100 feet, but some of our properties aren't even that big," she said.

Mathes of the U.S. Forest Service said homeowners should be aware that his agency instructs its firefighters to save only those homes that can be safely protected -- not those with piles of fuel built up around them.

"When we go through those areas, we see houses with dense, dry vegetation right next to the house. We even see firewood stacked against the house," he said.