The first time I saw one of the largest trees on Earth was by accident. I took a southern route from the East Coast to Lake Tahoe, stopping for an afternoon in Yosemite’s Mariposa Grove. Without knowing it, I chose a trail that passed one of California’s earliest tourist attractions: the now-fallen Wawona Tree, a giant sequoia so large it had a wagon tunnel carved through it in 1881 to lure visitors.