Harvesting wild local produce in Brooklyn’s Prospect Park may not seem like the best idea. And yet, on a foraging tour of the lively public park last month, a straw-hatted forager named “Wildman” Steve Brill and his teenage daughter, Violet, led roughly 40 of us amateurs into the grassy areas beyond the park’s paved footpaths for a four-hour tromp. Among plastic wrappers and bottle caps we found edible roots, fragrant herbs, and sturdy greens, all ripe for experimentation in the adventurous cook’s kitchen.
At least in theory. There was food here, for sure, but hardly of the practical variety. We recovered fallen pods from the Kentucky coffeetree, whose seeds can be used to brew a caffeine-free alternative to a morning cup. That is, if one is willing to harvest enough of them, wash them of green toxic goo, and roast them for hours—though even then, it won’t really be coffee. I stuffed a few pods in a canvas bag alongside sassafras root, once used to make root beer the old-fashioned way, and a handful of lettuce-flavored violet leaves that could, in the right quantities, constitute a small salad. Two weeks later, I’m still wondering what, if anything, I’ll actually make with these odd new ingredients.
What I didn’t anticipate were all the medicinal plants. Just a few minutes into the tour, we came across enough wild analgesics and anti-inflammatories to insure a casual hike. Here among the cigarette butts was broadleaf plantain, an easy-to-miss herb (unrelated to the bananalike fruit) known for calming mosquito bites. Over near the urinating puppy was jewelweed, which soothes poison-ivy and stinging-nettle rashes. Twigs snapped from a black birch tree exuded wintergreen oil, also known as methyl salicylate, a relative of aspirin that powers pain-killing ointments such as Bengay and Icy Hot.
Interest in foraging for food has taken off in recent years, owing in part to the gourmet-ification of eating locally and in part to its popularity on social media, where influencers make chips out of stinging nettles and add fir needles to granitas. Foraged ramps and morel mushrooms have become so well known that they now appear on restaurant menus and in high-end grocery stores. But the foraging boom has largely left behind what has historically been a big draw of scrounging for plants—finding treatments for minor ailments. To be clear, medicinal plants aren’t likely to save the casual forager’s life, and they lack the robust clinical data that back up pharmaceuticals. But even some scientists believe they can be handy in a pinch. In a way, being able to find a jewelweed stem is more useful than identifying a handful of leaves that can substitute for lettuce.
That has definitely been the case for Marla Emery, a scientific adviser to the Norwegian Institute for Natural Research and a former research geographer for the U.S. Forest Service who studies community foraging. Several years ago, when huge, oozing blisters formed on her legs after a run-in with poison ivy on a hunting trip, Emery visited an herbalist in Scotland who applied lobelia, an herb with pale-violet flowers, and slippery elm, a tree with mucilaginous properties, to her calf. Soon, she felt a tingling sensation—“as if someone had poured seltzer over the area”—and within an hour the blisters had healed, Emery told me.
Both plants, traditionally used to treat skin conditions, “are supportive of health and have medicinal value,” she said, and they’re especially useful because “you’re highly unlikely to poison yourself” with them. Such anecdotes illustrating the profound utility of medicinal plants are common among botanist types. “If you get a cut and put [broadleaf] plantain on it, you can see it close up,” Alex McAlvay, an ethnobotanist at the New York Botanical Garden, told me. At least for some species, he said, “the proof is in the pudding.”
Though foraging has long been a medicinal practice, and so many modern drugs are derived from plants, in the West, medicinal flora has largely been relegated to “traditional” or “folk remedy” status. Still, their use lives on in many communities, including immigrant groups that “come with medicinal-plant uses from their homelands and seek to continue them,” Emery said. People in Chinese, Russian, and certain Latin communities in the U.S. commonly forage dandelion, a weed with diuretic properties, to support kidney and urinary-tract health, she added.
Along the concrete footpaths of Prospect Park, the Brills pointed out stands of burdock; its roots, in addition to being a tasty potato dupe, are used in some cultures to detoxify the body. Pineapple weed, found in baseball diamonds and sidewalk cracks, can calm an upset stomach, Steve told me later. Scientific data for such claims are scant, much like they are for other foraged plants, and using the plants for health inevitably raises questions about scientific credibility. Many medicinal plants that a casual forager will encounter in the wild will not have been studied through rigorous clinical trials in the same way that any prescription drug has been. Whether people ultimately embrace foraging for medicinal plants depends on how they believe “we make evidence and truth,” McAlvay said. “A lot of people are like, ‘If there’s no clinical research, it’s not legit.’ Other people are like, ‘My grandma did it; it’s legit.’” Nothing beats clinical research, though clearly some plants share valuable properties with certain drugs. Lamb’s quarters, a dupe for spinach, is so packed with vitamin C that it was traditionally used to prevent scurvy; stinging nettle, traditionally used for urination issues, may have similar effects as finasteride, a prostate medication.
Naturally, the experts I spoke with unanimously recommended using foraged medicinal plants only for minor ailments. Just as foraging for food comes with some risks—what looks like a delicious mushroom can make you sick—the same is true of medicinal foraging. Take established, reputable classes and use books and apps to correctly identify plants, many of which have dangerous look-alikes; the edible angelica plant, for example, is easily confused with poisonous water hemlock, of Socrates-killing notoriety. Learning about dosage is important too. A benign plant can become poisonous if too large a dose is used, warned Emery. When working with medicinal plants, she said, “you’ve got to know what you’re doing, and that doesn’t lend itself to the casual TikTok post.” Beginner foragers should stick to “gentle but definitely powerful, easy-to-identify herbs,” such as dandelion and violet, said McAlvay.
As the Brills instructed, when I got home I submerged a foraged jewelweed stem in witch hazel to make a soothing skin tincture. Days later, when I dabbed some onto a patch of sunburn on my arm, I felt, or maybe imagined, a wave of relief. Whatever the case, my delight was real. When I had asked both tour-goers and experts why foraged medical plants mattered in a world where drugs that accomplish the same things could be easily bought at a pharmacy, some said it was “empowering” or “satisfying,” but the description that resonated with me most came from McAlvay, who called it “magic”: the power to wield nature, in nature, in order to heal.
When I got home from the tour and opened my bag of foraged goods, I found a black birch twig, still redolent of wintergreen. Coincidentally, that is the one smell I have craved throughout 38 weeks (and counting) of pregnancy, but moms-to-be are advised to avoid the medicinal ointments containing the oil. I sniffed the twig deeply, again and again, recalling that it might become useful in the months to come. When teething infants are given black birch twigs to chew, the gently analgesic qualities of the low-dose wintergreen oil helps soothe their pain, Brill had said. All of a sudden, their crying stops. What’s more magical than that?