At her feet, a snake-like cactus winds among thickets of spiny ground bromeliads ("my nemesis," she calls them), thorny shrubs and the bulbous stem of the devil nettle. We had camped the night ...

After cutting away the leaves to reveal the piña (so called because it resembles a big, bulbous pineapple), most ... subsist on night-blooming flowering cactus plants and sometimes cactus fruit ...