We walked through the lush foothills of Sichuan heading north along the rim of the Tibetan Plateau. The villages all had new concrete roads. The roads served cars and truck traffic. We tried to take shortcuts through the hills on old paths that had been worn by foot travel since time immemorial but now were fallen out of use. The forests had overgrown them. And we got lost and had to return to the roads. An aged cucumber farmer, Mr. Liu, offered to guide us, but he too got lost in the resurgent forest. “It’s around here somewhere,” he’d say, scampering up steep muddy slopes through the new undergrowth, swinging a bamboo stave and looking for the trails of his younger life. “It’s around here somewhere.”