Steve Brill’s first stop was the green behind the bike racks. Brill, known as Savage Steve, picked up a weed with heart-shaped seed pods and a small white flower with four petals. About thirty people gathered for a three-hour tour of Prospect Park in Brooklyn. The plant was shepherd’s purse, a name that indicates the resemblance of the seed pods to the containers shepherds used to make sheep’s bladders. “It’s the mustard family,” Brill said. “Most flowers in the mustard family have four petals in the shape of a cross.” He encouraged everyone to take a bite and tell him what the vegetable tastes like. Someone asked if we should be concerned about pesticides. “Don’t worry, they don’t have money for pesticides,” Brill replied. “And they’re pretty good in Prospect Park anyway. In Central Park, don’t eat anything there. he exaggerated; he’s been on the occasional foraging tour in Central Park for about forty years, and was once arrested there for eating plants, after which he was invited to the David Letterman show to make a forage salad.
Grass tastes like carrots? Do you like okra? Like broccoli, almost exactly. “Shepherd’s purse is one of the softest varieties in the mustard family,” Brill said, then plucked what I thought looked like a dandelion but wasn’t. “Here’s something sharper,” he said. It was another member of the mustard family called the poor man’s pepper. He drew our attention to the jagged leaves. Like shepherd’s purse, poor man’s pepper is an invasive weed that came from Europe. “I picked up a lot of this in the Rockaways this morning,” he said. He planned to cook “poor man’s potatoes” – potatoes (unleavened) with a lot of peppers for the poor (spicy). The common name goes back to a time when spices were a luxury item. In addition to taste, spicy food is often a preservative and antibacterial agent.
We went deeper into Prospect Park. In a shady place, Brill again asked everyone to pause. There was a sweet aroma. It was the smell. . . jasmine? vanilla? “It’s the smell of a flowering acacia tree,” he said. But we couldn’t see a single one. The black locust is considered an invasive species in the northeast—a big weed, you might say—but it also has flowers that are good in salads or pancakes. “Must be nearby,” he insisted. Someone pointed to a tree with white flowers in the distance. “It’s a dogwood,” Brill said with a mischievous smile. “You can always recognize a dogwood by its bark.”
Another weed wedged us into history. “This is delicious. another deadly,” Brill explained, pointing to an innocent-looking broad-leaved plant called lakos. This plant is native to North America. Its venom is water soluble, and it’s also a huge source of vitamin A that was once hard to come by in autumn and winter. It used to be periodically boiled—the poison washes out—and then used as a treatment by Native Americans and non-Native Americans when the telltale signs of vitamin A deficiency appeared, such as skin irritation, infections, and night blindness.
Someone brought greens. “Oh, it’s a white snake root, also very poisonous,” Brill said. “So it’s a native plant.” When cows were sent to graze in the forest, they sometimes developed what is known as milk sickness. Cows could live, but people who drank their milk often didn’t. Abraham Lincoln’s mother died of milk sickness, and entire communities of settlers moved when the disease broke out. They didn’t know what caused it. Nineteenth-century physician Anna Pierce Hobbs Bixby observed that this was a seasonal phenomenon and concluded that it must have been due to what the cows were eating. In Illinois, she befriended a Shawnee medicine woman—we know her only as Pierce, named Aunt Shawnee. Aunt Shawnee stayed after her tribe was forced out to the West; she taught Pierce that the responsible weed is the weed with clusters of small, delicate white flowers. Pierce tested the theory by feeding flowers to a young calf that had developed symptoms of milk sickness. Do you think people believed her? Diamond asked. “No, of course not. They said it was fake news and it was decades before her work was accepted.”
One way to think of weeds is as a plant in an undesirable location. Ralph Waldo Emerson described weeds as plants “the virtues of which have not yet been discovered,” and even the usually less exuberant Henry David Thoreau wrote, “Shall I not rejoice in the abundance of weeds whose seeds are the breadbasket of birds?” Weeds can also be seen as absorbing the sun and nutrients that other plants need, as well as the insects, birds, and humans that depend on these plants. Weeds can be underestimated; weeds can be bullies.
IN “Weed Lives: Opportunism, Resistance, Stupidity”, starting in 2021, scientist John Cardina charts the trajectory of some Shakespearean-like plants as they are no longer perceived as nobody, then as heroic medicinal or nutritional plants, then as villainous weeds, and perhaps again and again. again. repeatedly. Or perhaps a closer resonance to “Lives of the Saintswith plants sometimes pushing whole new geographies into spaces meant for them to breed, nourishing the locals, or saving the soil, or ruining other crops, or all of those things. Weeds make beautiful portraits of ambiguity. Cardina told me, “I’m trying to make a distinction between plants that are invasive in the natural environment and plants that appear and interfere with agriculture.”
Weed Life is organized around eight plants: dandelion, Florida weed, velvet leaf, sedge, mare’s tail, gauze, ragweed, and foxtail. Consider the history of the velvet leaf, an unusually hardy plant with silky fibers. In the nineteenth century, corduroy was called American jute and was the hope of the United States maritime industry as it was used to make rope, a key element of national defense. But this hope was not justified; Today, the exceptional ability of the velvet leaf to grow in disturbed soil has turned it into a weed that infects soybean crops. Velvetleaf and soybeans originally developed under similar environmental conditions in China. When World War II increased demand for domestic sources of oils and fats, soybeans were grown, and then velvet leaf. Herbicides that have been developed to kill the velvet leaf have resulted in stronger, herbicide-resistant varieties; today it is one of the most problematic weeds in agriculture, often surviving what farmers sometimes refer to as “spray and pray”. Cardina ends the chapter on the velvet leaf by describing how its ancient seeds were found in a jar dating back to the Neolithic period. Careful seed collection suggests that it was a valuable crop.
In the conversation, Cardina said, “It’s a strange irony that the methods we have for weed control are more sophisticated and better than they’ve ever been in a thousand years of farming, but weeds that survive are more difficult.” Cardina grew up in rural Ohio, served in the Peace Corps, earned her Ph.D. in horticulture and horticulture, worked briefly for the US Department of Agriculture; he has witnessed many shifts in thinking about weeds. He said that once herbicide-resistant weeds became dominant, “the answer was: keep developing the technology.” He sees weeds in agriculture as “a human problem, not a weed problem. We don’t want farms getting bigger and bigger and fewer and fewer people looking after the landscape and managing the land. It’s more of a social thing than a technological one.”
One story in the book follows the arc of a beggar woman, a member of the legume family. Cardina describes weed the way a philosopher sheriff talks about conflicts with a criminal he respects. Early in his career, when he worked as a research agronomist for the USDA, Cardina worked in Georgia, where a beggar woman flooded the peanut fields. (They also infested corn, cotton, and soybeans, but peanuts had the hardest time.) A local farmer explained to him that the beggar had been in the peanut fields for years, but she wasn’t that big. problem until recently.
At the end of the nineteenth century, the beggar was considered an excellent fodder crop. Letter to the editor in southern cultivator described it as producing “the tastiest hay, thousands of pounds an acre” with such a large yield that “there will never be another poor cash cow from the coast to the blue ridge”. The beggar thrived where other fodder crops did not thrive and did not need to be replanted. Then, after the 1920s, when tractors replaced horses and mules on farms, fewer fodder crops were needed. At this point, the beggar woman could become a common weed. It is a self-pollinator and therefore has the relatively limited capacity for genetic variability and rapid adaptation that often characterize plants that take over.
But the beggar woman has benefited from the miraculous development of herbicides. By the mid-twentieth century, herbicides had become more advanced and were better at killing selectively. Some herbicides killed grasses but not broadleaf plants; some killed small-seeded plants, but not large-seeded ones. The beggar woman had long been traveling with peanut plants; although they look very different, beggar plants and peanuts have similar metabolisms. When the herbicides began to kill the grassy and broadleaf weeds that plagued the peanut crops, the beggar suddenly had far fewer competitors.
In 1986, when the billion-dollar American peanut industry began to rely on a herbicide called Dinoseb to control the weed, Dinoseb was suddenly declared illegal. (This has been found to increase the risk of birth defects in female field workers and infertility in men.) Calls began to ring for Cardina. “Peanut farmers, peanut butter growers, peanut dealers, peanut haulers, peanut dryers. . . peanut traders, speculators in the peanut market. . . were angry and mad,” he wrote.
What is a weed and what weeds play the role of villains is constantly changing. Cardina mentioned a species of bedstraw that has recently become a problem in Canada. In North Dakota, flea beetles were introduced because they feed on leafy spurge, which the nonprofit Weed Society of America describes as “a noxious weed that affects more than 800,000 acres of the state.”
I asked Cardina what he thought about the weeds that usually appear in abandoned lots and other places in cities. “Weeds are adapted to disturbance,” he said. “And thank God they are there—they cover the soil, start sequestering carbon, decompose, and add organic matter to the soil.” But, he added, urban greenery can include poison ivy or oriental bittersweet creeper, which burdens the trees.
In Iceland, the Alaskan lupine, an invasive species, covers many fields and is very beautiful. Weeds are sometimes seen as a symbol of strength and resilience. In Tanzania, the beggar woman is known by a term that, according to Cardin, roughly translates to “spiritual plant,” a name that honors her tendency to appear in the most unexpected places. In Montreal, the greenery that sometimes grows out of sewer grates is called the tree of paradise. Cardina feels that humans, like many weeds, have a lot of plasticity, and when he tries to find a sense of hope, it lies in a person’s ability to change and adapt.
Cardina concludes her book of essays on the giant foxtail, which “became a major weed only because of remarkable chemical innovation, industrial development, cheap food policies, Cold War rivalries, and confidence in the unlimited availability of resources.” For a time, he tried to predict when the foxtail would appear in order to offer a “foxtail forecast” so that farmers could use less herbicides at more reasonable times to control it. He did a difficult job trying to understand weed germination, but farmers didn’t feel comfortable risking a new approach to weed control.
