Stephen C. Sillett (born March 19, 1968) is an American botanist specializing in old growth forest canopies. As the first scientist to enter the redwood forest canopy, he pioneered new methods for climbing, exploring, and studying tall trees. Sillett has climbed many of the world’s tallest trees to study the plant and animal life residing in their crowns and is generally recognized as an authority on tall trees, especially redwoods (Sequoia sempervirens). He is the first Kenneth L. Fisher Chair in Redwood Forest Ecology for the Department of Biological Sciences at Humboldt State University. He is featured in Richard Preston's New York Times best seller The Wild Trees, as well as in academic journals, general interest magazines, and nature television programs. He lives in Arcata, California, with wife Marie Antoine, a botanist and fellow forest canopy research scientist.
Sillett was born March 19, 1968 in Harrisburg, Pennsylvania. He has a younger sister, Liana, and an older brother, Scott, who is also featured in The Wild Trees. Both Sillett brothers were inspired to pursue careers in science by their grandmother, Helen Poe Sillett, who was a bird enthusiast.
His wife, Marie E. Antoine, a fellow botanist, lectures at Humboldt State University and assists Sillett in his field research. They were married on December 8, 2001.
Sillett studied biology as an undergraduate to pursue his interest in botany, later refocusing on tall trees and Lobaria, a type of nitrogen-fixing lichen associated with old-growth forests, in the Pacific Northwest. He received his Bachelor of Arts from Reed College in Portland, Oregon, in 1989 at the age of 21. He went on to receive a Master of Science in Botany from the University of Florida in 1991, and a Doctor of Philosophy from Oregon State University in 1995. He began teaching at Humboldt State University 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 Humboldt State University.