As she neared her third birthday, Josephine made a ritual of riding her plastic tricycle before dinner. She’d roll toward the BART station, gathering smiles from commuters walking home. Every day she would pedal about two blocks before deciding she would prefer to find something filthy on the sidewalk to put in her mouth. And then I would carry both her and the tricycle home.One day, as she was riding along and scanning the ground for something suitably vile to eat, I noticed an exuberant stand of wild fennel growing beside a telephone pole. Wild fennel springs up wherever there is exposed dirt in my neighborhood. You can’t see the bulbs like the fennel you find in supermarkets, but its feathery leaves are sweet, and taste like licorice.Sensing an opportunity to channel Josephine’s attraction away from sidewalk detritus, I plucked a tender shoot and held it out to her. “Do you know what this plant is?”She shook her head gravely.“Fennel. Some people call it candy plant.”“Candy plant?”I had her attention. I handed her the sprig.“Can I eat it?”And for once, I could say yes. Of course, it’s not totally safe …