Foraging used to be a quirky niche, filled most notably by “Wildman” Steve Brill, who for years has led foraging tours in the Northeast, including in Central Park. (He now sells a foraging app, too.) But foragers today are an eclectic bunch, including downtown hipsters, recent immigrants, vegans and people who do not believe in paying for food.

Even those who would never dream of plucking sassafras during a walk in the park can read about it. The magazine Edible Manhattan has an “Urban Forager” column (as does The New York Times’s City Room blog). And the current issue of Martha Stewart Living features a colorful spread about foraging on Ms. Stewart’s property in Maine — but at least all those plants belong to her.

While it has long been against the rules to collect or destroy plants in the city’s parks, with potential fines of $250, the city has preferred education to enforcement. “It’s listed in the prohibited uses of the parks, and the simple reason is that if everyone went out and collected whatever it is — a blackberry or wildflower — the parks couldn’t sustain that,” said Sarah Aucoin, director of urban park rangers for the Department of Parks and Recreation.

Officials have not gone as far as posting signs in Central Park that foraging is prohibited, for fear they would serve as arrows pointing to the most delectable areas. Ms. Hernandez of the park conservancy would take a reporter on a tour of edible plants only on the condition that their locations not be revealed.