Should you pick wild greens by the roadside?
Foodthink Says
In recent years, wild vegetables and wild fungi have become increasingly popular. Not only are various premium wild greens and mushrooms appearing in mainstream supermarkets, wet markets, and online fresh produce platforms, but “foraging” (the act of picking wild greens and fungi) has swept through the youth as a new trend, with many travel agencies launching “foraging tours” to capitalise on the craze.
On one hand, wild greens and fungi are coveted as pure, pollution-free foods; on the other, news reports of people being hospitalised after consuming them are all too common. Is it actually safe to forage in urban green spaces? Where do the wild vegetables and mushrooms sold in markets and online actually come from? Are they really healthier and more nutritious? Are the “mysterious benefits” attributed to matsutake mushrooms credible? And what kind of natural history and nature education do we truly need?
Recently, Foodthink and Tencent Science’s *Species on the Table* invited four farmers, natural history writers, anthropologists, and ecologists to discuss the nuances of eating wild greens and mushrooms. For a discussion on the biodiversity of wild vegetables and fungi, please refer to our previous issue, *Everything Green is a Vegetable, Everything that Moves is Meat*.
Roundtable Guests
I. From Beijing to Canada: A Farm Where Nature is Allowed to Run Wild
Sun Shan: I grew up in Beijing. One of my childhood memories of wild greens is frequently accompanying my mother to pick shepherd’s purse; we would come home and wrap them into dumplings, which tasted wonderful. I imagine many of my peers born in the 70s who lived in the north may have had similar experiences. Looking back, foraging was actually quite hard work, especially with shepherd’s purse. It gets very muddy and has to be washed bit by bit, and even then, you might still crunch into a bit of grit when eating it.
Sun Shan: As an adult, I studied ecology and worked in biodiversity conservation and biomedical research, but ironically, I had fewer opportunities to get my hands dirty foraging like I did as a child. It wasn’t until I became a farmer ten years ago that I started cultivating vegetables in my own plots. During the cultivation process, alongside the usual vegetables, a defining characteristic of our ecological garden is that we allow things to “grow wild”—essentially permitting so-called agricultural weeds to flourish. Many of these “weeds” are, in fact, edible wild greens. For instance, I’m particularly fond of the nettles that sprout this season; they are actually highly nutritious vegetables.
II. Is it safe to forage for wild vegetables in the city?
Tan Lingdi: I believe that foraging for and eating wild vegetables is a way of connecting with nature and appreciating biodiversity. As an environmental educator, it actually makes me quite happy to see people foraging.
Of course, cities are zoned. In wilder, less-populated areas, you can follow the principles of sustainable harvesting—meaning that while there may be plenty of wild greens, you only take a small amount so as not to disrupt the wild ecological environment.
In crowded public green spaces, such as the Olympic Forest Park in Beijing, you should not forage. Firstly, it is prohibited there. Secondly, I believe wild vegetables serve more than just a culinary purpose; they have aesthetic value, and for other flora and fauna, they may be a vital food source. Therefore, in these high-traffic areas, please refrain from picking—leave some for others to admire and some for the animals to eat.
Then there is the possibility that if you forage in a managed area, what you find might actually be cultivated. I suggest that before picking, check whether the area is under urban greenery management, a crowded spot, or someone else’s land; avoid these places.
Most importantly, avoid picking anything poisonous. If you do not recognise a plant, absolutely do not touch it. When designing urban green spaces, many designers intentionally avoid planting edible plants, while also avoiding highly toxic ones. This is because they fear people might forage and eat them, and subsequently, they would be held responsible if someone were poisoned.
As a conservationist, from a biodiversity perspective, we certainly hope urban green spaces use fewer pesticides and herbicides. However, people often have demands for urban greenery that exceed its natural capacity—for instance, we cannot tolerate pests, or we want a single species to form a street-lined avenue, a sea of flowers, or a perfectly manicured lawn. These things are impossible to achieve if plants are left to grow wild. Consequently, the use of agrochemicals, including insecticides and herbicides, is still very common in urban green spaces. Although low-toxicity pesticides are primarily used, ‘low toxicity’ does not mean they are edible, so it is best not to take the risk.
III. I was poisoned by wild vegetables
Li Ruijun: Whenever people hear I research wild fungi, they always ask if I’ve ever been poisoned. I used to joke, “I’ve never been poisoned, but I’m constantly flirting with the edge of it.”
Then last year, I actually did get poisoned by wild vegetables. It was something we eat regularly: broom, a yellow legume flower that can be used in soups or fried with eggs. My whole family loves it; every year as soon as broom hits the market, we buy some. Because it is so commonly eaten, many assume it is non-toxic. But last year, I suffered poisoning—likely because I ate too much and exceeded the safe limit. I felt dizzy, nauseous, and my heart raced, as broom does indeed contain mild toxins. My family didn’t really react to my condition, so I ended up lying down for an entire afternoon until the symptoms subsided. Therefore, one must indeed be cautious when eating wild vegetables. It is easy to categorise things we eat frequently as ‘risk-free’, but in reality, many wild greens carry risks.
IV. Foraging for Wild Greens on Campus to Treat Constipation During the Lockdown
Li Ruijun: That experience was actually quite interesting. During the pandemic in Shanghai, a few friends and I were staying in university offices. Due to the exceptional circumstances, we ate the same few things every day, and there were very few vegetables. Consequently, something rather embarrassing happened—we all became constipated. I am not usually someone who suffers from constipation, but I was no exception this time, likely because of the lack of daily vegetables.
To eat more greens and treat the constipation, my Yunnanese genes kicked in, and I thought about searching the university’s green spaces for some wild vegetables that could ‘clear internal heat’. I eventually found plenty of dandelions. At first, I had some reservations, as the university gardeners sometimes use pesticides or fertilisers. So, I only dug up some dandelion roots, washed them, dried them, and used them to brew tea.
Li Ruijun: During that period, there was hardly anyone at the university and very little supervision. The usually manicured lawns were overgrown with all sorts of wild weeds. As my constipation worsened, I decided I really had to find some wild vegetables to eat. Later, I found plenty of wild aster (*malantou*) by the river on campus, which were exceptionally plump and tender. The river was actually right next to a laboratory in one of the university’s faculties, which gave me some pause. But the situation was so extreme—if I didn’t eat them, I’d stay constipated—so I went ahead and ate them. I was aware that the risk of poisoning is related to dosage; picking a small amount by the river every day and eating it in moderation was fine.
Li Ruijun: At the time, the university had come to a standstill, and it felt as though time for society had stopped too, which only amplified my own biological clock. I had never been so acutely aware of the phenology—of the seasonal rhythms. After Qingming came Guyu (Grain Rain), and the growth of all things matched those specific periods. So, as different wild vegetables appeared, I began searching for them.
In mid-April, when I started eating the wild aster, it was still very tender. I would harvest it, blanch it, and then serve it as a cold salad or simply boil it in a soup, which felt wonderful. I became addicted and started searching the campus for other wild greens. By then, the shepherd’s purse had already grown tough, and the alfalfa had bloomed and likewise toughened. Later, in the flowerbeds, I found wild peas with white and purple flowers. I knew they were edible, so I ate them like pea shoots. But after two or three days, they too had grown tough.
Li Ruijun: What helped me most during that time was image recognition software. I was quite bold; whenever I saw something, I would identify it first, then scroll to the very bottom of the results to see if it was edible. If it was, I’d pull it up and have a taste; if the flavour was okay, I’d take it back and look up how to cook it. Subsequently, I found and ate wild onions, Toona sinensis, black jelly fungus, and bamboo shoots. For the first time, I felt a different kind of sensory shock: the absolute freshness of spring.
V. The accelerating cultivation of ‘wild vegetables’
We have also noticed that many things we assume to be wild vegetables are now actually cultivated. Banxia, have you observed this phenomenon in the markets of Yunnan? How do you view this shift?
Banxia: In Yunnan, there is a saying—’mountain and thatch’ (shan mao). ‘Mountain’ refers to mountain delicacies, and ‘thatch’ refers to wild grasses; it describes things that grow wild. However, these are gradually becoming domesticated. Even now, in November, I can buy Chinese Toon transported from Xishuangbanna. But in my opinion, the taste of Toon from Xishuangbanna is quite different from that of the Toon growing on trees in the villages around Kunming. Yunnan is currently aggressively developing its ‘under-forest economy’, and many species are now cultivated. Even Termite Mushrooms and Lingzhi can be artificially grown now, let alone woody wild vegetables. Species like Huolian-cai and Liangwang-cha are emerging woody vegetables; most of those sold in shops and stalls are now cultivated.
Banxia: Cultivated wild vegetables are becoming more and more common. If you want to taste truly authentic wild vegetables, it is best to avoid the large markets. On weekends, I visit some Yi ethnic villages on the outskirts of Kunming to buy them. The first time I tasted Shaozi-jian was from one of these village markets. For instance, you can find both wild and domesticated Shepherd’s Purse in the markets, but the wild variety is far more delicious and fragrant. I believe the appeal of wild vegetables lies in that concentrated, bold flavour.
Banxia: Currently, one of the most expensive wild vegetables in Yunnan is the bamboo leaf vegetable, a plant from the lily family. This ‘mountain and thatch’ vegetable was recommended to me by a market vendor; I had never seen it before. It generally looks like a small bamboo shoot, with leaves resembling bamboo. Harvesting bamboo leaf vegetables is incredibly difficult because they grow under very strict conditions, only found at the 2,800-metre snow line. Because they age very quickly, a highly efficient logistics network is required for transport. To save time, foragers often have to venture into those areas with torches while it is still dark. However, because the profit margins are so high, it is hard to say whether people will eventually create or simulate an ecological environment to grow them.
With the strong development of the under-forest economy, everyone is focusing on scientific breeding. My father was a true enthusiast of Chinese edible fungi. In the early 1980s, he subscribed to the magazine *Chinese Edible Fungi*; he was probably the only person at the mine who did so. My family started eating Matsutake back in the 1970s. My father had a book called *Edible Fungi of Yunnan* with colour illustrations, and based on the images and descriptions, he identified the Matsutake. At that time, there was no such thing as commercial trade in Matsutake; the local people called them ‘big flower mushrooms’ because when they cracked open, the patterns looked like a flower. Once my father determined they were Matsutake, he told the local children in the mountains to bring any they found to our house. We ate them for several years, and they were very cheap—just five cents for a large one. Later, when I returned home after finishing my studies elsewhere, I could no longer find them. My father told me that people had begun buying them up for trade.
Li Ruijun: Whether a food is ‘healthy’ or ‘natural’ is, in fact, more of a human-constructed concept that reflects our perception of the environment. Take the Termite Mushroom, for example. It has a symbiotic relationship with termites and can only grow on termite mounds. Consequently, everyone considers it a superior product, believing it cannot be artificially manipulated or treated with chemicals, and therefore must be naturally healthy. However, Termite Mushrooms can actually be cultivated; while they aren’t mass-produced yet, experimental cultivation has been successful.
Another successfully domesticated variety is the black-skinned Termite Mushroom. It is a fungus of the *Oudemansiella* genus and is saprotrophic, which is completely different from the symbiotic *Termitomyces* genus of the standard Termite Mushroom. In the market, however, the black-skinned variety capitalises on the consumer’s imagination of the Termite Mushroom as something ‘natural and healthy’, and it sells exceptionally well.
VI. The best way to approach nature education is to start at the dining table
Banxia: Liu Huajie, an advocate for the culture of natural history in China, once used four English words to explain “Bowu” (natural history): “Beauty” (the great beauty of nature), “Observation” (meticulous observation, recording, classification, and exploration), “Wonder” (a childlike sense of awe, seeing everything as a miracle), and “Understanding” (seeking understanding and sustainable symbiosis).
Recently, he introduced a new concept where the letter B has become “Body”—meaning our physical selves. We are discovering more and more that nature can heal us, so the body and health are vital; stepping into nature is a healthy way of living. O has become “Open”, as in opening the body and the mind. W has become “Wild”, and U has become “Usually”, referring to the ordinary and the everyday.
Banxia: What is natural history? It is simply being interested in something in the natural world and then seeking to know it, observe it, classify it, describe it, and eventually form an emotional bond with it. It means having an emotional connection to nature. I am also an independent volunteer for natural ecology and biodiversity conservation. Regarding the invasion of apple snails in Yunnan’s Fuxian Lake and Erhai Lake, I used social media to call for a “people’s war” against these unfriendly invasive species. Eventually, the local government issued a notice formally “declaring war” on the apple snails.
This article was first published in the “Let’s Talk Science” series on Tencent News
Reprinted with authorisation by the Foodthink official account
Compiled by: Muye
Edited by: Tianle