Many California trees survived the wildfires. Here’s why.

In the charred landscapes left behind by the Los Angeles wildfires, a persistent sign of life has transfixed locals: trees.

On lots where houses have been reduced to piles of rubble and cars to mangled metal husks, trees rise. These surviving oaks, pines and orange trees are often the only remaining landmarks in a neighborhood, bittersweet reminders of a time before so much tragedy.

The trees’ survival was a curiosity to many. Shouldn’t they have burned alongside homes?

In reality, trees are fairly fire resistant, and many will likely recover, resprout and stick around for years. Even some non-native species that are known for being combustible, like eucalyptus trees, still linger. These surviving beauts, some with singed trunks and leaves, are a sign of hope for many Californians, for whom the state’s mythology and aesthetics are so wrapped up in trees.

California is famously home to the oldest, tallest and largest trees in the world. Three national parks there are named for trees, as well as several cities, including Oakland and Palm Springs. And what more immediately evokes Los Angeles, the state’s most populous city, than a row of lanky palm trees, bowing their heads under a blue sky?

“Part of what makes a community feel homey is old trees, having green in our urban landscape, having big trees, having shade,” said Anna Jacobsen, plant ecology professor at California State University, Bakersfield. With so many trees still standing in communities where little else is left, she said, perhaps soon these “places can start to feel like home again.

The trees survived because they are filled with water: The roots draw moisture from soil and transport it through branches to its leaves.

When the fires erupted in January, trees in Los Angeles had been especially nourished after two previous rainy winters. All that water makes burning a living tree akin to trying to start a campfire with wet logs, Dr. Jacobsen said.

Trees are more likely to burn if they have dried leaves, such as browned palm fronds, which can act as kindling if not removed. But if properly watered and maintained, “there’s nothing inherently dangerous about a tree,” said Dr. Jacobsen.

Houses are much more combustible, built with lumber and filled with furniture and other objects made of wood and plastic that are quick to ignite.

The Los Angeles fires largely jumped from home to home, with nearby trees being harmed, but not always destroyed, by the embers spewed by the burning structures, according to officials from Cal Fire, the state’s firefighting agency.

Douglas Kent, a landscape architect who specializes in fire safety, said that native trees, such as coastal oaks, are especially fire resistant, with thick bark and waxy leaves that prevent flames from doing serious damage. But during a recent drive around Altadena, he noticed that older trees of all species – even highly combustible types like palm and eucalyptus – seemed to survive the blazes, probably because they had deep roots.

“That was a shocker,” said Kent. “What I saw in Altadena was that if you were deep-rooted, you survived. Native or not, it didn’t make a difference.”

For some homeowners, familiar trees beckon as they wrestle with whether to return to their otherwise unrecognizable neighborhoods.

Pat Harrison’s midcentury bungalow in Altadena boasted a view of scrubby mountains nearby, and in the 14 years she lived there, mountain lions, bears and coyotes regularly visited her backyard. Harrison, 67, is unsure if she wants to return to Altadena after her home and so many others on her block were destroyed.

But the towering pine trees that lined her driveway and the 100-year-old oaks in her backyard appear to have survived, she said, making her property look far less “post-apocalyptic.”

“With them,” she said, “it’s easier to imagine rebuilding.”