The bark of an older redwood tree can be up to 12 inches thick and is remarkably fire-resistant.

Redwood Trees Have Astonishingly Fire-Resistant Bark

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While wildfires rage through California forests, one ancient tree stands defiant: the coast redwood. These towering giants can survive fires that would incinerate other species, thanks to bark that acts like nature's fireproof suit.

The secret lies in sheer thickness. Mature redwood bark can grow up to 12 inches thick—some specimens even reach two feet at the base. That's about the width of a standard laptop, wrapped around the entire tree.

Nature's Flame Retardant

Thickness alone doesn't tell the whole story. Redwood bark is saturated with tannins, the same bitter compounds found in tea and wine. In redwoods, tannic acid acts as a natural flame retardant, making the bark stubbornly resistant to combustion.

The bark also maintains high moisture content and lacks pitch or resin—the accelerants that turn pine trees into towering torches during fires. Some researchers describe redwood bark's fire resistance as having "asbestos-like qualities," creating a protective shield that prevents flames from reaching the vulnerable sapwood beneath.

An Evolutionary Advantage

This isn't just a cool quirk—it's a survival strategy millions of years in the making. Coast redwoods have evolved alongside fire, developing these defenses to outlast periodic burns that clear competing vegetation.

Young redwood sprouts won't survive fire, but mature trees can endure repeated burns over centuries. Some ancient redwoods bear fire scars from dozens of wildfires, each one a historical record etched in charcoal.

When fire does penetrate the bark, redwoods have a backup plan: dormant buds hidden beneath the bark for centuries can sprout new growth, sometimes from buds over 1,000 years old.

Why It Matters Today

As wildfires intensify with climate change, understanding redwood fire resistance has never been more relevant. These trees offer a living blueprint for survival in fire-prone landscapes.

The same properties that protect redwoods make their lumber prized for construction in fire-risk areas. But the real value lies in preserving these ancient forests themselves—living monuments to resilience, some over 2,000 years old, that have weathered countless fires and continue to thrive.

Frequently Asked Questions

How thick is redwood tree bark?
Mature redwood bark can grow up to 12 inches thick, with some specimens reaching nearly two feet thick at the base of the tree.
Why don't redwood trees burn in wildfires?
Redwood bark contains natural flame-retardant tannins, maintains high moisture content, and lacks flammable pitch or resin found in other trees. Combined with extreme thickness, this creates exceptional fire resistance.
Are redwood trees completely fireproof?
No tree is completely fireproof, but mature redwoods are remarkably fire-resistant and can survive repeated wildfires over centuries thanks to their protective bark.
Can young redwood trees survive fire?
No, young redwood sprouts will not survive fires. Fire resistance increases with age as the protective bark thickens over decades and centuries.
How do redwood trees recover after fire damage?
Redwoods can sprout new growth from dormant buds hidden beneath the bark, sometimes activating buds that are over 1,000 years old to regenerate after fire damage.

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