Cofounder of Heronswood Nursery, Dan has a penchant for plants from mountainous regions, but also a (rather inconvenient) fear of heights. You learn to live with it, he says. "I don't freeze anymore when I come to a precipice, but they're never going to be my favorite spots." His preferred haunt is China: "There's incredible diversity there because its plant palette wasn't wiped clean by the last ice age, which missed China."
Home base: Indianola, Washington
Travels to: Asia, including Sikkim in northeastern India, Australia, New Zealand, South Africa, and South America.
Memorable misadventure: "In 2002, we were robbed by Maoist rebels and held for ransom twice on a Nepalese expedition, and the hotel next to us in Kathmandu was bombed on the same trip. Rebels and terrorists are the worst danger there."