ON A RECENT SATURDAY morning in San Francisco’s Golden Gate Park, throngs of joggers, tourists, and gutter punks streamed through a thousand acres of trails, gardens, and picnic groves—but I was there for the weeds. As I hovered over a patch of lamb’s quarters by Lincoln and Fifth Avenue, I recalled tasting some a few weeks earlier at a farmers’ market, the plants’ dusty leaves covered in a powdery white film, with spiky clusters of tiny flowers and red-streaked stems. I was surprised by how delicious they were: a more flavorful, hearty, and textured spinach. Subsistence on a weed—an unwanted but abundant wild plant—appealed to me. I was determined to forage my own, but did not want to make a mistake and die by poison hemlock, so I signed up for a “wild food walk,” a two-hour class led by Kevin Feinstein, author of The Bay Area Forager. Foraging in San Francisco public parks, it should be noted, is forbidden by city ordinance.

We had barely passed the threshold between sidewalk and park perimeter when our small group identified several edible plants, including cleavers, yarrow, oxalis, and wild chamomile. Identifying plants, especially weeds, requires a fine-tuned sensitivity to texture and detail, to the serration of leaf edges and the raised cilia of slender stems, all of which is easily overlooked by the coarse observer. The distinctions are less like that between Bob Dylan and Bach, and more like the changed timbre between mandolin and violin strings. Though I’m no stranger to Golden Gate Park, it occurred to me that I was seeing (and touching) some of these plants for the very first time.

Soon, I began to notice the differences in how these unassuming plants grow, flower, smell, and taste. Each seemed unlike the next, no longer just anonymous members of the “weed” category, that universal label for undesirables. I was reminded of the word inscape, Gerard Manley Hopkins’s term for the individuality of the elements within a landscape. For Hopkins, nature was not an all-encompassing, abstracted whole; it was composed of distinct and mortal beings. To identify plants—and to notice the weeds, the uncivilized, uncouth specimens of the garden order—is to see the inscape, the extraordinary particularity of every living thing.

Our attention soon shifted to the com-mon mallow, a plant with long, branched stalks, toothed leaves, minuscule purple flowers, and immature seed pods, which resemble petite, green cheese wheels. Our leader told us that the cheese wheels are the most delicious part of the mallow—crunchy and sweet, with beta-carotene for nutritional value. He advised us on the sustainability of foraging—only take what regenerates, he said—and was emphatic about its lawlessness. But his admonition sounded almost like a dare: You take full responsibility for what you choose to forage and eat, so do so at your own risk. Dare you pluck and eat a weed? Dare you see the forgotten, neglected orphans of the plant world?

We did dare, we did, so we plucked little cheese wheels off the mallow and passed them around like communion wafers, breaking open the pods and eating.