Photoalto/jerome Gorin/Getty Images
The towering presence of a redwood tree is unrivaled. From Albert Bierstadt’s sweeping canvases to Luke Skywalker’s daring escape in a redwood forest in “Return of the Jedi,” these giants have captured the imagination of artists and filmmakers alike. The National Park Service even incorporates a redwood into its logo, honoring the species as one of the nation’s most treasured natural wonders.
While redwoods are often associated with the United States, the family includes the dawn redwood (Metasequoia glyptostroboides) found in central China. That species is the smallest of the group and bears little resemblance to the majestic trees that dominate California’s forests. The iconic giants we know belong to two species: the giant sequoia (Sequoiadendron giganteum) and the coast redwood (Sequoia sempervirens). With the exception of a small patch of coast redwoods in southern Oregon, these species are native only to California.
Redwoods are renowned for their height and age. The tallest living tree, a coast redwood named Hyperion, reaches just over 380 feet in Redwood National Park. The largest by volume is the giant sequoia General Sherman in Sequoia National Park. Both species can live for more than 2,000 years, but height and longevity are just the beginning of what makes these trees remarkable.
HWall/Shutterstock
Beyond their grandeur, redwoods support a rich ecosystem high in their branches. Many birds, such as the endangered marbled murrelet (Brachyramphus marmoratus) and the northern spotted owl (Strix occidentalis caurina), use the high canopies for nesting and roosting. The marbled murrelet’s eggs are laid in the upper limbs, while the spotted owl relies on natural hollows in the trunk for nesting, underscoring the importance of healthy redwood stands for these species’ survival.
Even amphibians find refuge in the canopy. The wandering salamander (Aneides vagrans) can glide between branches without the wing‑like membranes seen in other gliding species. Recent slow‑motion footage reveals that the salamander controls its fall using elongated limbs and a tail, effectively performing a controlled descent.
HWall/Shutterstock
Redwoods shed their leaves continuously, and over centuries these fallen leaves accumulate on branches, decomposing into deep mats of soil—sometimes up to three feet thick—high above the forest floor. This creates a miniature ecosystem where epiphytes thrive. More than 200 epiphyte species—mosses, berries, and even trees like Sitka spruce and western hemlock—call the canopy home.
The most significant of these is the leather‑leaf fern (Polypodium scouleri). Its mats can extend eight feet across, offering habitat for salamanders and insects. Ferns capture up to 5,000 gallons of rainwater per acre, which redwoods and other epiphytes tap into. In turn, redwoods grow aerial roots that reach into these mats, forming a symbiotic water‑storage system.
Bob Pool/Shutterstock
Despite their massive size, redwoods possess an astonishing genetic complexity. The Redwood Genome Project, completed in 2021, revealed that coast redwoods contain 26.5 billion base pairs—almost nine times the human genome’s three billion. Moreover, coast redwoods are hexaploid, with six sets of chromosomes, compared to the diploid state of both humans and giant sequoias.
Analysis shows that coast redwoods evolved from a single ancient ancestor, not from hybridization. They harbor unique genes that confer resistance to fungal disease, physical damage, and drought, offering critical insights for conservation and climate resilience.
Tracy Immordino/Shutterstock
Wildfires, paradoxically, are essential for the giant sequoia’s life cycle. Fires clear understory vegetation and expose mineral‑rich soil, creating ideal conditions for seed germination. The species’ cones, containing roughly 200 seeds each, remain sealed until exposed to high temperatures, at which point they burst open and scatter seeds across the fire‑cleared floor.
Sequoias boast bark up to two feet thick, providing natural fire resistance. However, they are adapted to periodic, low‑intensity fires that recur every one to three decades. The increasing frequency and intensity of modern wildfires threaten to outpace their resilience.
Supercaliphotolistic/Getty Images
Along California’s rivers—such as the Klamath, Smith, and the creeks within Redwood National and State Parks—salmon and other fish migrate upstream to spawn. Redwoods help maintain these waterways: their roots stabilize banks, and their canopies shade streams, keeping temperatures within the optimal range for salmon.
In return, dying salmon enrich riverbeds with marine nutrients, creating fertile soil that benefits the redwoods. The health of one species is tightly linked to the other, illustrating a profound ecological partnership.
James Yu/Getty Images
Carbon dioxide, the primary driver of climate change, is sequestered most efficiently by tall, long‑lived trees. Coast redwoods and giant sequoias absorb and store vast amounts of carbon in their massive trunks and expansive canopies. Their longevity allows for long‑term storage, but logging and intensified wildfires can release this stored carbon back into the atmosphere, underscoring the need for sustained forest protection.
Historical/Getty Images
Before the westward expansion of the United States in the mid‑1800s, Northern California’s old‑growth redwoods covered roughly two million acres. Gold rush settlers and the lumber industry rapidly harvested these trees, decimating about 95% of the old‑growth stands within a century.
Both the coast redwood and giant sequoia are now listed as endangered on the IUCN Red List. Conservation efforts began in earnest with the 1968 purchase of 60,000 acres that became Redwoods National Park, now spanning 130,000 acres with 40,000 acres of old growth. The park, in partnership with conservationists, actively re‑plant and nurture young trees, using controlled burns and selective cuts to strengthen future generations.
These initiatives lay the groundwork for the restoration of old‑growth forests that will endure for centuries to come.
