Stephen Sillett gets called in for the really big jobs. When two naturalists discovered an extraordinarily tall coast redwood tree in northern California's Redwood National Park last summer, they decided it needed to be measured. They thought it might be bigger than the tallest known tree, a 370.5-foot redwood. But they couldn't be sure until someone scaled the new giant, which they named Hyperion. That's when they turned to Sillett.
Sillett first measured the tree from the ground with a laser range finder. He estimated that it was at least 378 feet tall. But he would need to climb to the top to know for sure.
Sillett is a professor of botany at nearby Humboldt State University, in Arcata, California. He has studied redwoods for 11 years. His specialty is the redwood-forest canopy, or the very tops of the trees. He gets there by--you guessed it--climbing. "The views are incomparable," Sillett told TFK. "You see a part of the forest that is basically invisible from the ground."
Last fall, Sillett reached new heights. After a couple of hours of climbing Hyperion, he lost sight of the forest floor. When he got to the top, he sent a measuring tape down the tree's length. He knew he had scaled the world's tallest tree. Hyperion was a majestic 379.1 feet.
No matter how many mighty giants he climbs, Sillett is still in awe of their sway over the forest. Redwoods have much to teach scientists, he says. The species is ancient, and some trees are as old as 2,000 years. They are able to bounce back from fire, rot and other damage. Their hardiness makes them one of nature's soaring success stories. "It's an amazing phenomenon (that) an individual plant that starts from a seed as big as a fingernail clipping can grow to 379 feet," Sillett says.