Humboldt State University

Humboldt State Now

HSU Prof Confirms World’s Tallest Tree - Humboldt State Now

HSU Prof Confirms World’s Tallest Tree

Dr. Stephen Sillett, Professor and Kenneth L. Fisher Chair in Redwood Forest Ecology at Humboldt State University, recently measured and verified that Hyperion—a 379.1-foot tall redwood tree, is truly the world's tallest living tree. Hyperion is the largest of three redwoods discovered this summer, which eclipse the previous world record holder, a 370.5-foot tall redwood dubbed Stratosphere Giant.

Dr. Stephen Sillett, Professor and Kenneth L. Fisher Chair in Redwood Forest Ecology at Humboldt State University, recently measured and verified that Hyperion—a 379.1-foot tall redwood tree, is truly the world’s tallest living tree. Hyperion is the largest of three redwoods discovered this summer, which eclipse the previous world record holder, a 370.5-foot tall redwood dubbed Stratosphere Giant.

This past July and August, two naturalists, Chris Atkins and Michael Taylor, discovered three trees in a remote section of northern California’s Redwood National Park, which they believed were taller than Stratosphere Giant. They returned with fellow redwood researcher, Dr. Stephen Sillett, who helped them collect measurements with a laser range finder. They named the largest of the three trees, Hyperion.

Though Sillett immediately estimated Hyperion’s height at over 378 feet tall, he abstained from officially declaring it a world record until he could climb and measure the tree himself. Laser range finders are fairly accurate devices, but it is not always possible to hit a tree’s highest leaf from the ground when using such a device. The most accurate means of measuring a tree’s height is to climb into its crown and lower a fiberglass tape from the top. That climb to the top, however, was delayed for two weeks by a park restriction intended to protect nesting marbled murrelets—an endangered species of bird that inhabits the area.

When the murrelet’s nesting season came to a close, Sillett climbed Hyperion and verified its status as the tallest tree. The discovery is part of an ongoing collaboration between Atkins, Sillett and Taylor. The three have been searching the range of redwood to document all living trees over 350 feet tall. So far they have found 136 individual redwood trees over 350 feet tall. When they began their work in the 1990s, only about 25 such trees were known.

“The only reason these discoveries are made,” says Professor Sillett. “is that a group of people are willing to go out looking for them. I’m lucky to be associated with Michael Taylor and Chris Atkins. We thought we’d mopped it up, as far as finding the tallest trees goes. No one has ever seen anything like this. It’s the most significant discovery in tree height in 75 years. It’s been pretty miraculous”

Location, Location, Location

Several things make Hyperion’s discovery surprising—even to the scientists who’ve dedicated their every waking moment to finding and researching such trees. The first was its location on a steep slope. Most giant redwoods take root in creek bottoms, where the soil is rich and water is plentiful. The other surprise is simply that trees of this size actually exist.

The Redwood Creek basin, where Hyperion is located, was thoroughly logged during the 1970s before Jimmy Carter’s administration redrew the boundaries of Redwood National Park — an act which silenced the chainsaws in that particular neck of the woods.

“If you look at a map, it’s just amazing,” explains Professor Sillett. “Most of Redwood National Park has been cut. There are really just a few drips and drabs of old growth left in there, and in these little bits that are left, there are these tall trees lurking—and we just found them. One of the amazing things about this discovery is that we learned that this park expansion in 1978 really did save the tallest trees. No one has realized that until this summer.”

The Leading Redwood Researcher

There are few people on earth, better suited to discussing giant redwoods than Dr. Sillett. The Humboldt State University professor changed the way the scientific world looked at these trees, when he became the first scientist to climb to the tops of old growth redwoods and discovered a rich, world of life forms, hundreds of feet above the forest floor. Sillett’s research has been published in Nature, the American Journal of Botany, Ecological Applications, Bryologist, Northwest Science and other publications. His work has also been profiled in The New Yorker, Discover, New Scientist and the National Geographic.

“There is also a lot about biological diversity in the crowns that’s been unexpected,” explains Professor Sillett. “What I found were these phenomena that had never been seen before—these huge soil accumulations, hundreds of feet above the ground with salamanders living in them. There were ferns, shrubs, and trees growing on giant limbs, literally hanging gardens up there. I realized that these forests were capable of supporting a diverse range of life up there in the canopy.”

What’s happening in treetops has been a long and abiding interest of Sillett’s. He started climbing trees as an undergraduate at Reed College and completed his bachelors thesis on lichens in an old-growth Douglas-fir forest near Portland. Sillett studied tropical rain forest canopies in Costa Rica while working on his Masters degree. In 1991, Sillett went to Oregon State to do his Ph.D. on forest canopies in the old-growth Douglas-fir forests of the Cascade mountains.

When Sillett was offered a job at Humboldt State in 1995, he viewed it as a golden opportunity. “No one had really done anything scientific above the ground in redwood forests before,” he recalls. “I was really in the privileged position to be the first scientist to be able to explore the redwood forest canopy. So, it’s been a long-standing interest with trees that’s grown into an obsession with the tallest trees.”

Sillet’s research received a major boost this past spring, when renowned investor and Humboldt State alumnus, Ken Fisher, established the world’s first endowed chair to support the study of the redwood forest. The gift that supports the named chair will provide approximately $90,000 annually, representing investments of approximately $3.6 million, to support research in redwood ecology in perpetuity. The chair funds a Humboldt State professor’s release from half of their teaching schedule to focus on research and also provides support for graduate students, laboratory and field equipment and other needs. As the first Kenneth L. Fisher Chair in Redwood Forest Ecology, Professor Sillett can intensify his exploration of redwood ecology.

Sillett was further recognized this fall, when Humboldt State’‘s President Rollin Richmond announced that Sillett had been chosen as the University’s 2006 Scholar of the Year.