Can a tree be resistant to fire? Surprisingly, yes. Despite being made of wood, some tree species have evolved to withstand and even thrive in fire-prone environments. This remarkable trait is why giant sequoias have endured in California’s wildfire-prone landscapes and why longleaf pine forests in the American Southeast flourish with regular fires.
WHAT MAKES A TREE FIRE-RESISTANT?
Fire-resistant trees share several common features:
• Thick Bark: Protects the inner cambium layer, which is crucial for growth.
• High Moisture Content: Wood or leaves with high moisture burn slowly and less intensely.
• Lack of Low Branches: Prevents flames from reaching the treetops.
GIANT SEQUOIA
Giant sequoias, with bark up to 3 feet thick, were once thought to be fireproof. Their high branches prevent fire from reaching the canopy, and their cones open with heat, allowing seeds to sprout in fire-cleared soil.
PONDEROSA PINE
This evergreen thrives in western forests, thanks to its thick bark, protective bud scales, and deep roots. Its open branching structure and moisture-rich needles help it resist fire.
CORK OAK
Native to the Mediterranean, cork oaks have thick, honeycomb-like bark that protects the tree’s living layer. This allows the tree to recover quickly after a fire.
LONGLEAF PINE
Thriving with regular low-intensity fires, longleaf pines have thick bark and long needles that protect the growing tip from heat. Smaller fires prune lower branches, preventing larger flames from reaching the canopy.
These fire-resistant trees are nature’s remarkable survivors, adapted to withstand the challenges of their fiery environments. As an organization planting millions of trees in forestlands facing more challenges than ever — including increasing wildfire threats — the Arbor Day Foundation works with partners who have local knowledge and knowhow to select the trees best suited for local and regional ecosystems to ensure they not only survive, but thrive.
A FIRE THAT SPARKED A MOVEMENT
The devastating wildfires that swept through Los Angeles this winter hit close to home for many of our supporters and partners in the region. As we reached out to check on their safety, we found ourselves reflecting on how our work in wildfire recovery first began — back in Yellowstone, 1988.
It started slowly. Just one lightning strike in a remote location — forests survive them every day.
Then another, and another, and another. Before long, one of America’s most beloved national parks was consumed by flames.
That June, Yellowstone was experiencing the beginnings of what would become the worst fire in the park’s history. A historically dry summer had set the stage for destruction — and soon, 45 fires were blazing within its borders.
More than 25,000 firefighters battled the wildfire. Media coverage was so intense that many believed the park had burned completely to the ground.
By September of that year, snow and rain extinguished the last of the blaze. But the damage was daunting. Roughly 800,000 of the park’s acres — a third of its land — was burned. Across the region, 1.2 million acres had been scorched.
“It wasn’t just Yellowstone. Gallatin National Forest on the north side of the park was heavily affected,” says Brad Brandt, senior program manager at the Arbor Day Foundation. “Somebody here wanted to see if we could help fundraise to get trees back in the ground. They reached out to the Forest Service, and it took about two years to raise the money.”
At the time, funding public reforestation with private dollars wasn’t common. Such work was usually completed with the Forest Service’s limited budget. And the Foundation’s main focus was sending trees to members in cities and town, not reforesting large rural lands.
The Yellowstone fires changed all that. Donations poured in from supporters who had watched the harrowing coverage and felt compelled to help.
Recovery work began in spring 1990, when more than 125,000 white pine, Douglasfir, and lodgepole pine trees were planted across the forest’s burn scar. Each seedling was planted by hand.
This partnership continued for a decade, until 1.3 million new trees covered the land.
“We could not have the planting program we have without the Arbor Day Foundation and its members. It is their contributions, large and small, that make this happen,” says Stan Cook, a forester who led the restoration efforts at the time.
Since that first project, the Foundation has funded the planting of more than 50 million trees with the Forest Service.
And though much has changed since 1990, western states continue to need more assistance. The Arbor Day Foundation has even identified global forests through data and mapping that need more reforestation efforts now. The American Pacific West, largely driven as a result of the worsening wildfire seasons that continue to plague the region, are one of five priority areas the Foundation is directing more support toward.
“When the Yellowstone fires hit, it was almost a signaling of what was to come,” Brandt said. “There’s a fire regime people in the West have to live with now. Fire seasons are longer. They’re more intense. And there’s a lot more money being invested in preventing and managing them.”
THE VITAL ROLE OF FORESTS IN WATER SUPPLY
Healthy forests are essential for maintaining a healthy water supply. They provide drinking water to over 150 million people in the United States and are the source of 75% of the world’s freshwater. Planting more trees across watersheds worldwide is crucial for our future.
HOW DO TREES SUPPORT WATER?
Tree roots stabilize the soil, reducing erosion and preventing sediment from entering waterways. Rainwater slows down and absorbs into the soil, recharging aquifers deep in the Earth. This process filters out pollutants like nitrates, phosphates, and pesticides, keeping water clean for people and wildlife. Economically, this natural filtration is invaluable. For instance, New York City invested $1.5 billion in a forest protection program in the Catskills, resulting in some of the cleanest drinking water in the country. Building a filtration plant would have cost over $8 billion.
Trees also store and release water vapor through their leaves, promoting healthy rainfall patterns. Loss of forests can lead to drought and other climate effects far from the deforested area.
THE POWER OF TREES IN THE WEST
The American Pacific West faces severe water supply challenges due to persistent drought and climate change, drying up major waterways like Lake Powell, Lake Mead, and the Colorado River. This has led to historic wildfires, worsening the problem as more trees are lost.
Los Angeles, recently on the frontlines of devastating wildfires earlier this year, relies heavily on trees for its water supply, with 30% of residents’ drinking water originating from the nearby Angeles National Forest. This forest is home to the endangered big cone Douglasfir, which grows only in a small area of southern California. The forest also provides recreation for millions of visitors annually.
In 2016, the Sand Fire burned over 40,000 acres of Angeles National Forest. The Arbor Day Foundation responded by supporting the planting of 60,000 big cone Douglasfirs to replenish the water supply, provide habitat for wildlife, and restore the area for future generations.
It’s clear the connection to water and trees continues to be an intersection where the work of the Arbor Day Foundation is having an outsized positive impact, thanks in large part to our member and partner support.
