Sillett began teaching at
Cal Poly Humboldt in 1996, where he dedicates much of his time to field study of not only coast redwood but also giant sequoia (
Sequoiadendron giganteum), Douglas-fir (
Pseudotsuga menziesii), Sitka spruce (
Picea sitchensis), and the tallest trees of the Southern Hemisphere,
Eucalyptus regnans and
E. globulus. He currently teaches courses in General Botany,
Lichens and
Bryophytes, and Forest Canopy Ecology at Cal Poly Humboldt. In addition to studying redwood canopies, Sillett studies other tall forests in the US, Canada, and Australia. He has climbed and measured the tallest of each of the six tallest trees species. Sillett and his team do not disclose precise locations of the world's tallest trees. Sillett allows only students and research team members to climb with him, to maintain both the security of the trees and the safety of fellow researchers.
Major accomplishments • Discovery of the redwood
Grove of Titans in 1998, accompanied by
Michael Taylor. • In 2006, Sillett measured and verified the redwood
Hyperion as the world's tallest tree at 115.55 m (379.1 ft). Previous record-holder
Stratosphere Giant is 112.83 m (370.5 ft). • Sillett, wife Marie Antoine, brother Scott, and other climbing and research companions including Michael Taylor and Chris Atkins are featured in Richard Preston's book
The Wild Trees.
Discover,
New Scientist, and
National Geographic. • Sillett has been profiled on nature television programs such as National Geographic's
Wild Chronicles,
BBC's
Planet Earth, and
PBS's
Oregon Field Guide. ==Personal life==