Fungi of Aotearoa: A curious forager’s field guide stormed the bestseller charts upon its release, clearly serving a local interest in the mushrooms around us. The following is an edited excerpt, along with some of the eye-poppingly beautiful photos you’ll find throughout the book.

Fungi are medicine for us

Fungi may help us heal the Earth, reduce our impact on her, and could be a key collaborator in another, more intimate environment too – our own bodies. Superbugs are scary-as. They resist almost every kind of antibiotic, and they’re on the rise in Aotearoa as well as the rest of the world. They cause staph infections and other gnarly health complications, and by some estimates could kill more frequently than cancer by 2050. But there’s good news: fungi may be able to fight superbugs. Fungi are one of the foundations of modern medicine. Penicillin, the first mass-produced antibiotic, came from Penicillium fungi. Antibiotics alone have added 23 years to the average human life expectancy.

Before we had them, one in every nine skin infections led to death. Penicillin ushered in a roaring period of antibiotic discovery. This period produced drugs like cyclosporin, which suppresses the immune system and makes things like organ transplants possible. Cyclosporin was found when a pharmaceutical company encouraged employees to bring soil samples from their holidays back to the lab, to see if they contained any useful fungal strains. Fungi have actually been used as medicine for a lot longer than antibiotics have been around. Māori used fungi as medicine as well as kai. Pūtawa were cut into strips and used to dress wounds. Puffballs were used to stop bleeding and to treat burns and scalds. Tawaka was given to expectant mothers and to people suffering from fevers. It was also used to treat karaka and tutu poisonings. Angiangi and other lichens were collected and used to dress wounds and slow bleeding.

In China, fungi have been used as medicine for thousands of years. Medicinal mushrooms first appeared in Taoist art around 1400 ad, around the same time that the first Polynesian peoples may have arrived in Aotearoa. Superbugs, however, pose a scary question — are we in a post-antibiotic era? Antibiotic-resistant superbugs, like MRSA, have become more resistant and harder to fight each year. In 2014 the World Health Organization warned that within a decade, antibiotic-resistant bacteria could make routine surgeries really risky and write the end of modern medicine. In Aotearoa, our geographical isolation has offered a slight superbug buffer. 

But in 2009, the first case of a carbapenem-resistant organism (CRO) was identified here. Carbapenems are a high-powered group of antibiotics used to treat infections that other drugs can’t. Every year, more patients with CROs are identified in Aotearoa. Our current antibiotics have got us this far, but we need new ones. The good news is that there’s still loads of potentially useful fungi out there – we just haven’t had enough time to get to know them all yet. But we’re working on it. Siouxsie Wiles and her bright pink locks graced our TV screens almost daily during the Covid lockdowns. She kept us up to date on the facts, breaking down the jargon so that Kiwis everywhere could better understand what the heck was going on. Since 2015, Siouxsie has been working with Bevan Weir to investigate local fungi for potential antibiotic applications. Our flora and fauna are wildly different compared with those in the rest of the world, and the same is true of our fungi. What we have here is unique, and could hold what we need to make some new medications.

Importantly, we also have the International Collection of Microorganisms from Plants (ICMP). Located in Auckland, this collection holds 23,000 living cultures – strains of fungi, bacteria and other microorganisms stored frozen in tanks of liquid nitrogen. This collection is the product of 70-plus years of work and is one of the best in the world. It contains more than 10,000 fungi species from Aotearoa and all over the Pacific and could well be an untapped trove of useful compounds. In one of Siouxsie’s lab’s early findings, 35 out of 36 fungi samples from the collection showed some kind of activity against mycobacteria, a family of superbugs that includes Mycobacterium tuberculosis, which causes TB. The lab has also identified a fungal strain with some activity against the hospital superbug methicillin-resistant Staphylococcus aureus, better known as MRSA. So what does this mean? Have we got a new wonder drug, a penicillin 2.0? Not quite. The scientific process is rigorous and thorough, and so it’s normally quite slow. Identifying potential candidates is just step one, with many steps between that and actually using something in a drug trial. Our Covid-19 vaccines were developed quickly, but only on the back of decades of research into mRNA vaccines.

Now, why do fungi “work” for us as medicine? To start with, fungi can’t “run away” from threats like pathogens, so they have evolved clever counter-strategies – an entire arsenal of chemical responses to fight off whatever bacteria or other nasties come their way. And their defence strategies often work really well for us too. But why? At the core of things, we’re not that different. We are genetically quite similar to fungi and are pestered by many of the same viruses. Fungi produce many chemical compounds to protect themselves, but the best understood are the beta-glucans, which have been shown to stimulate weak immune systems. Many of the most treasured mushrooms in traditional medicine, like Ganoderma species, are high in these compounds. Our shared history with fungi is another key part of this puzzle. 

Animals, including humans, that have been able to identify and use fungi as food and medicine have gained physiological benefits in the short term. And evolutionary benefits in the long term. Along the way we have evolved to have receptor sites where we can process and use what fungi provide. As a result, when we consume medicinal fungi they trigger healing, nourishment, defence – or all three.

Fungi are magic

Every so often, magic mushroom spores end up in a council woodchipper. Once that woodchip is spread, warm rain coaxes curious fungi into being on library lawns and along police station sidewalks. These fungal blooms fire up furtive Facebook groups and bring out a different kind of forager. Magic mushrooms contain psilocybin, a mind-altering (psychoactive) substance that is a Class A drug in Aotearoa. It’s illegal, as are the mushrooms themselves.

They pose a high risk of harm to humans. So how does this happen on council’s watch? There isn’t anything dodgy going on — magic mushrooms grow up and down Aotearoa, all of their own accord. We even have a few native and endemic species. Their spores are often dispersed by the wind and, when those spores come to land on woody debris, and that woody debris comes to land in the woodchipper, councils can end up being co-conspirators in the spread.

Humans and other animals are known to seek out altered states of mind. Kererū, our native wood pigeons, eat fermented miro berries and sometimes fall out of trees when they overindulge. Kids spin around to get dizzy. Adults use caffeine to dial in, and alcohol to wind down. In his book How to Change Your Mind, American author Michael Pollan writes, “There is not a culture on earth that doesn’t make use of certain plants to change the contents of the mind whether as a matter of healing, habit, or spiritual practice.”

This got Dr Mitchell Head (Tainui, Ngāti Mahuta, Ngāti Naho) thinking. Did, or does, rongoā Māori — traditional healing — make use of the mind-altering substances that naturally occur in the ngāhere? Were early Māori aware of endemic, psychedelic mushroom species such as Psilocybe weraroa? Mitchell is a neuroscientist whose research sits at the intersection of science and mātauranga Māori (Māori knowledge). He’s looking into how Psilocybe weraroa could be used as a medicinal product to treat addiction in conjunction with a cultural therapeutic framework. This fungus contains psilocybin and is a taonga (sacred) species. Now, an illegal substance . . . that might be used for therapy? At first glance it doesn’t add up. But there are incredibly strong signals, both current and historical, that substances like psilocybin magic mushrooms can be used as powerful additions to our mental health toolkit.

Peyote, a spineless psychedelic cactus, has been used in Mexico and the American south-west for more than 6000 years. The Navajo, a Native American tribe, have used it to treat alcoholism and in ceremonies designed to connect people with spiritual power, guidance and healing.

Recent research in Aotearoa and abroad has found that psychedelics could be used to treat depression, addiction, and even the sense of dread that comes with terminal diagnoses. Psychedelics, importantly, are not addictive. And the benefits shown in these studies are often not only immediate, but lasting.

These kinds of applications are what Mitchell is interested in. But how do the benefits “work”? The “snow-globe” analogy helps explain this. Imagine going sledding after a fresh fall of snow. At the start of the day, you can choose any path down the hill. But after a few goes, the tracks of the previous runs are bitten into the hillside. After an hour or two, the original tracks are deep and established. Once your sled is on them, it becomes harder and harder to swerve and forge a new path to the bottom. Depression is often fuelled by repetitive ruminative thinking loops; addiction is a repeated behaviour. Both represent deeply rutted thinking patterns that are hard to deviate from.

Experiences, also called “trips”, induced by psychedelics have been likened to “shaking the snow globe”. When you turn the globe upside down and back again, the snow resettles, and this creates an opportunity for new paths to be taken. A psychedelic experience can disrupt unhealthy patterns of thought and create new, flexible ways of thinking and behaving, even if you’re fairly far down a difficult life-track. The benefits of psychedelics used as therapy, Mitchell taught me, can be seen in the way fungi operate in the natural world — they’re great at creating communication pathways. When you put them into the brain, they accelerate the growth of neuronal pathways. Every time we perform a particular behaviour, we create feedback loops and those behaviour pathways get reinforced. Psilocybin allows the brain to follow new pathways rather than staying in the same ruts. It’s all about putting energy into the system and allowing it to take a new path. As many indigenous cultures overseas have a history of using their native psychedelic species, it didn’t seem likely to Mitchell that Māori hadn’t experimented with theirs, too. Through his research and kōrero, he has found that there is indeed such knowledge but things like the Tohunga Suppression Act of 1907 forced discussion underground. During his research, Mitchell has found several accounts of traditional Māori use of magic mushrooms, generally passed on through oral tradition.

Mitchell is now working with a marae to develop a therapy for their people struggling with addiction. With the help of Manaaki Whenua, the group explored the bush around their marae and found Psilocybe weraroa. No one has yet quantified how much psilocybin these mushrooms contain. Mitchell is hoping to not only do that, but also determine a therapeutic dose that can be  achieved consistently. The second, and equally essential, part of this research is the cultural framework Mitchell is working on. Psychedelics are powerful substances. ‘Set and setting’ are key in producing a generally positive experience. Set refers to the mindset the user brings to the experience, while setting refers to the physical place in which it occurs. 

Indigenous practices, like Navajo peyote ceremonies and the Pacific kava ceremony, provide frameworks for set and setting. When psychedelics are used without this understanding, the experience could be quite scary. People should never look to forage their own magic mushrooms, Mitchell told me — more than a few who have tried in Aotearoa have had negative experiences. And, of course, it’s illegal. Currently we don’t have a framework for psilocybin use in a Māori cultural setting. When you take these substances as medicine, Mitchell explained, they act as catalysts for whatever kind of process you want to undertake. Defining the set and setting, and the intention behind taking the medicine, is really important. To design a cultural therapy to wrap around therapeutic psilocybin use, Mitchell has looked to other sacred ceremonies held on marae, such as tā moko (traditional tattooing), and is working with tohunga (healers) and cultural therapists in the marae setting who are experts in the spiritual space to develop this therapy.

Fungi are far from being just “one thing”. The various forms and definitions they take on know literally no bounds. From feast to famine, magic to malady, they have shaped the world as we know it. They have even shaped us. Our shared history with fungi is wild and wonderful. And it’s only just the beginning.

Fungi of Aotearoa: A curious forager’s field guide by Liv Sisson (Penguin NZ, $45) can be purchased from Unity Books Auckland and Wellington.