Michael Pollan: Mushrooms are Mysterious


I put that knowledge to good use the following week, when I returned to the oak tree near my house and found beneath it a gold rush of chanterelles. I hadn’t thought to bring a bag, and there were more chanterelles than I could carry, so I made a carrier of my T-shirt, folding it up in front of me like a basket, and then filled it with the big, mud-encrusted mushrooms. I drew looks from passers-by—looks of envy, I decided, though at the time I was so excited I may have gotten that wrong. So now I have a spot and, just like Jean-Pierre’s, it’s right here in town. (Please don’t ask me where it is; I don’t want to have to kill you.)
Once the rains stopped in April the chanterelles were done for the year, and there wouldn’t be another important mushroom to hunt until the morels came up in May. I used the time before then to read about mushrooms and talk to mycologists, hoping to answer some of the questions I had collected about fungi, a life form I was beginning to regard as deeply mysterious. What made mushrooms mushroom when and where they did? Why do chanterelles associate with oaks and morels with pines? Why under this tree and not that one? How long do they live? Why do some mushrooms manufacture deadly toxins, not to mention powerful hallucinogens and a range of delicious flavors? I brought the gardener’s perspective to these plantlike objects, but of course they’re not plants, and plant knowledge is all but useless in understanding fungi, which are in fact more closely related to animals than they are to plants.
As it happens the answers to most of my questions about mushrooms, even the most straightforward ones, are elusive. Indeed, it is humbling to realize just how little we know about this, the third kingdom of life on earth. The books I consulted brimmed with confessions of their ignorance: “it is not known why this should be” . . . “the number of genders among fungi is as yet undetermined” . . . “the exact mechanisms by which this phenomenon occurs are not entirely understood at this time” . . . “the fundamental chemistry responsible for the vivid hallucinations was a mystery then, and remains so today” . . . “it is not certain whether the morel is a saprophytic or a mycorrhizal species, or perhaps it is both, a changeling” . . . and so on, through thousands of pages of the mycological literature. When I went to visit David Arora, the renowned mycologist whose doorstop of a field guide, Mushrooms Demystified, is the West Coast mushroomer’s bible, I asked him what he considered the big open questions in his field. Without a moment’s hesitation he named two: “Why here and not there? Why now and not then?”

In other words, we don’t know the most basic things about mushrooms.
Part of the problem is simply that fungi are very difficult to observe. What we call a mushroom is only the tip of the iceberg of a much bigger and essentially invisible organism that lives most of its life underground. The mushroom is the “fruiting body” of a subterranean network of microscopic hyphae, improbably long rootlike cells that thread themselves through the soil like neurons. Bunched like cables, the hyphae form webs of (still microscopic) mycelium. Mycologists can’t dig up a mushroom like a plant to study its structure because its mycelium is too tiny and delicate to tease from the soil without disintegrating. Hard as it may be to see a mushroom—the most visible and tangible part!—to see the whole organism of which it is merely a component may simply be impossible. Fungi also lack the comprehensible syntax of plants, the orderly and visible chronology of seed and vegetative growth, flower, fruit, and seed again. The fungi surely have a syntax of their own, but we don’t know all its rules, especially the ones that govern the creation of a mushroom, which can take three years or  thirty, depending. On what? We don’t really know. All of which makes mushrooms seem autochthonous, arising seemingly from nowhere, seemingly without cause.


Fungi, lacking chlorophyll, differ from plants in that they can’t manufacture food energy from the sun. Like animals, they feed on organic matter made by plants, or by plant eaters. Most of the fungi we eat obtain their energy by one of two means: saprophytically, by decomposing dead vegetable matter, and mycorrhizally, by associating with the roots of living plants. Among the saprophytes, many of which can be cultivated by inoculating a suitable mass of dead organic matter (logs, manure, grain) with their spores, are the common white button mushrooms, shiitakes, cremini, Portobellos, and oyster mushrooms. Most of the choicest wild mushrooms are impossible to cultivate, or nearly so, since they need living and often very old trees in order to grow, and can take several decades to fruit. The mycelium can grow more or less indefinitely, in some cases for centuries, without necessarily fruiting. A single fungus recently found in Michigan covers an area of forty acres underground and is thought to be a few centuries old. So inoculating old oaks or pines is no guarantee of harvesting future mushrooms, at least not on a human time scale. Presumably, these fungi live and die on an arboreal time scale.


Mycorrhizal fungi have coevolved with trees, with whom they’ve worked out a mutually beneficial relationship in which they trade the products of their very different metabolisms. If the special genius of plants is photosynthesis, the ability of chlorophyll to transform sunlight and water and soil minerals into carbohydrates, the special genius of fungi is the ability to break down organic molecules and minerals into simple molecules and atoms through the action of their powerful enzymes. The hyphae surround or penetrate the plant’s roots, providing them with a steady diet of elements in exchange for a drop of simple sugars that the plant synthesizes in its leaves. The network of hyphae vasdy extends the effective reach and surface area of a plant’s root system, and while trees can survive without their fungal associates, they seldom thrive. It is thought that the fungi may also protect their plant hosts from bacterial and fungal diseases.


The talent of fungi for decomposing and recycling organic matter is what makes them indispensable, not only to trees but to all life on earth. If the soil is the earth’s stomach, fungi supply its digestive enzymes—literally. Without fungi to break things down, the earth would long ago have suffocated beneath a blanket of organic matter created by plants; the dead would pile up without end, the carbon cycle would cease to function, and living things would run out of things to eat. We tend to train our attention and science on life and growth, but of course death and decomposition are no less important to nature’s operations, and the fungi are the undisputed rulers of this realm.


That the fungi are so steeped in death might account for much of their mystery and our mycophobia. They stand on the threshold between the living and the dead, breaking the dead down into food for the living, a process on which no one likes to dwell. Cemeteries are usually good places to hunt for mushrooms. (Mexicans call mushrooms came de los muertos—”flesh of the dead.”) The fact that mushrooms can themselves be direct agents of death doesn’t exacdy shine their reputation, either. Just why they should produce such potent toxins isn’t well understood; many mycologists assume the toxins are defenses, but others point out that if poisoning the animals that eat you is such a good survival strategy, then why aren’t all mushrooms poisonous by now? Some of their toxins may simply be fungal tools for doing what fungi do: breaking down complicated organic compounds. What the deadly amanita does to a human liver is, in effect, to digest it from within.


The evolutionary reason many mushrooms produce powerful hallucinogens is even more mysterious, though it probably has nothing to do with creating hallucinations in human brains. As the word intoxication implies, substances that poison the body sometimes can change consciousness, too. This might explain why mycophiles think civilians make far too much of the dangers of mushrooms, which they see as occupying a continuum from the deadly to the really interesting. The dose makes the poison, as they say, and the same mushroom toxins that can kill can also, in smaller doses, produce astonishing mental effects, ranging from the ecstatic to the horrific. No doubt the mind-altering properties of many common mushrooms, known to people for thousands of years, have nourished the cult of mystery surrounding the fungal kingdom, in this case feeding both mycophobia and mycophilia alike.


Andrew Weil points out an interesting paradox about mushrooms: It’s difficult to reconcile the extraordinary energies of these organisms with the fact that they contain relatively little of the kind of energy that scientists usually measure: calories. Because they don’t supply many calories, nutritionists don’t regard mushrooms as an important source of nutrition. (They do provide some minerals and vitamins, as well as a few essential amino acids, which are what give some species their meaty flavor.) But calories are simply units of solar energy that have been captured and stored by green plants and, as Weil points out, “mushrooms have little to do with the sun.” They emerge at night and wither in the light of day. Their energies are of an entirely different order from those of plants, and their energies are prodigious and strange. Consider:


There are fungi like the shaggy mane (Coprinus comatus) that can push their soft fleshy tissue through asphalt. Inky caps (Coprinus atramentarius) can mushroom in a matter of hours and then, over the course of a day, dissolve themselves into a puddle of blackish ink. Oyster mushrooms (Pleurotus ostreatus) can digest a pile of petrochemical sludge in a fortnight, transforming the toxic waste into edible protein. (This alchemy makes more sense when you recall that what saprophytic mushrooms have evolved to do is break down complex organic molecules, which is precisely what petrochemicals are.) Jack o’lanterns (Omphalotus olivascens) can glow in the dark, emitting an eerie blue bioluminescence for reasons unknown. The psilocybes can alter the texture of human consciousness and inspire visions; Amanita muscaria can derange the mind. And of course there are the handful of fungi that can kill.


We don’t have the scientific tools to measure or even account for these fungi’s unusual powers. Weil speculates that their energies derive from the moon rather than the sun, that mushrooms contain, instead of calories of solar origin, prodigious amounts of lunar energy.


Okay, it is hard, I agree, to avoid the conclusion that some of the people who write about mushrooms have themselves partaken, perhaps immoderately, of the mind-altering kinds. Their reverence for their subject runs so deep that they will pursue it wherever it leads, even if that means occasionally leaping the fence of current scientific understanding. In the case of mushrooms, that’s not a very tall or sturdy fence. A powerful and compelling strain of mysticism runs like branching ; mycelia through the mycological literature, where I encountered one j incredible speculation after another: that the mycelia of fungi are liter- j ally neurons, together comprising an organ of terrestrial intelligence and communication (Paul Stamets); that the ingestion of hallucinogenic mushrooms by the higher primates spurred the rapid evolution of the human brain (Terence McKenna); that the hallucinogenic mushrooms ingested by early man inspired the shamanic visions that led to the birth of religion (Gordon Wasson); that the ritual ingestion of a hallucinogenic fungus—called ergot—by Greek thinkers (including Plato) at Eleusis is responsible for some of the greatest achievements of Greek culture, including Platonic philosophy (Wasson again); that wild mushrooms in the diet, by nourishing the human unconscious with lunar energy, “stimulate imagination and intuition” (Andrew Weil).


I’m not prepared to discount any of these speculations just because they’re not provable by our science. Mushrooms are mysterious. Who’s to say the day won’t come when science will be able to measure the fungi’s exotic energies, perhaps even calculate our minimum daily requirement of lunar calories?


This is an excerpt from Pollan’s nonfiction work The Omnivore’s Dilemma. The entire text is available to purchase online or at your local bookstore. More works by Pollan are available to borrow in the Wellness Within Lending Library.


Pollan, Michael. The Omnivore’s Dilemma: A Natural History Of Four Meals. New York : Penguin Press, 2006. Print.

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