Like many kids, Chris Sharma grew up climbing trees. He can still recall scrambling up branches in his parents’ backyard in Santa Cruz, California. But while adulthood forced most of us to abandon our arboreal pursuits, Sharma kept climbing. Now a world-renowned professional rock climber, he returned to his roots last month when he scaled a 77-metre (253 ft) sequoia in Eureka, California as part of Red Bull’s Giant Ascent project.

Sharma’s goal was not only to push the boundaries of his abilities (and have a bit of fun), but also to help biologists assess the health of the 600-year-old giant by collecting samples from the canopy.

Tree researchers need a head for heights and Dr Anthony Ambrose and Wendy Baxter, redwood experts from Berkeley University and former rock climbers, are well versed in rigging tactics and techniques. “I admit, I was pretty sceptical,” Baxter explains. Sharma had to scramble up 50 metres (164 feet) of bark before reaching the first branches and, just in case the challenge wasn’t demanding enough, he chose to free-climb, which means he only used his hands and feet and avoided climbing aids such as spurs.

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Pro-climber Chris Sharma took tree-climbing to new heights recently when he scaled a massive redwood tree for a project called Giant Ascent. Image: Keith Ladzinski/Red Bull

After three days spent meticulously mapping his route, Sharma eventually succeeded in reaching the canopy, where he collected samples that will help Ambrose and Baxter measure how the forest is faring in the face of California’s record-breaking drought.

“For me, climbing has always been about reconnecting to that playful side,” he says. “It can be so serious. You put your heart and soul into a hard rock project. But it’s also good to take a step back and remember that this is supposed to be about having fun.”

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Climbing a redwood has its own set of unique challenges. The repetitive pattern of the bark made it difficult for Sharma to learn his planned route. Image: Keith Ladzinski/Red Bull
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Getting a grip: Sharma compared the bark of the redwood to vertical limestone formations in Spain called 'tufas'. Image: Keith Ladzinski/Red Bull
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A high-powered crossbow was needed to shoot an arrow to the top of the canopy so support ropes could be put in place for the climb. Image: Keith Ladzinski/Red Bull


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The sequoia is estimated to be at least 600 years old. Image: Keith Ladzinski/Red Bull

Header image: Daniel