Rita Leistner still remembers the day she planted 6,000 trees. It was 1989, and she was working as a tree planter in the Canadian bush, a job she held from 1984 to 1993. Tree planters need to hit around 2,000 trees per day to make minimum wage; the best of them can exceed 5,000. “Most of that day is a blur because it was such an insane physical ordeal, but I’ll never forget the number,” she says. She estimates she planted half a million trees during that formative decade in her twenties.