Mushrooms can be mind-altering — but do they have minds?

A wet start to October has brought mushrooms up all over the place. Other fungi have appeared with them. One has just killed one of my 30-year-old ornamental pear trees. Suddenly all its leaves turned brown and it will have to come down and be burnt immediately. As it belongs with another 40 pear trees in four interrelated avenues, I am not exactly content. A honey fungus is probably the culprit.

Do we understand what is going on at the fungal level of life? It is certainly much in the news. Kew has just published its report for 2020 on the state of the world’s plants and fungi. So much remains unknown.

In 2019, 1,886 species of fungi received scientific names for the first time. About 148,000 of those in the world are identified, but they are believed to be only 10 per cent of the total in existence. We are living with fungal companions whom we do not yet understand.

Some of them have alarming powers. Can they think or even, perhaps, remember? The current best-selling title on gardening is Merlin Sheldrake’s Entangled Life, the first book by this Cambridge-trained biologist.

He does not have much of a literary style, but he has sat in the Panamanian jungle, deep in red mud, and studied fungi in nature. His subject is “how fungi make our worlds, change our minds and shape our futures”.

He has even offered to seed an unwanted copy of his book with Pleurotus mycelium and watch while this fungus eats its way through the pages and then sprouts oyster mushrooms from the covers. Then he will eat them and be the ultimate ecological author.

Only a fraction of the world’s fungal population throws up visible mushrooms. Some of them are notoriously potent. In January, four of Gwyneth Paltrow’s staff at Goop went on a psychedelic mushroom trip in Jamaica, where such tripping is legal.

Under “therapeutic supervision” they were filmed and then screened on Netflix weeping, giggling and, at times, claiming the experience had altered their lives.

Last month, Compass Pathways, founded in 2016, had its IPO on Nasdaq, planning a phase-three clinical trial for psilocybin, the crucial mushroom ingredient that the Goopers ate. If approved, psilocybin will be used to address cases of severe depression. They will not include early investors. Shares in the company rose to a 71 per cent high above offer price on day one.

If you missed out, you can book a legal mushroom trip to Jamaica with MycoMeditations and undergo three supervised sessions of psilocybin in seven days from about $5,000. No thanks: in 2016 the Lancet reported a scientifically run magic-mushroom trial, four of whose 12 main patients had mild vomiting and headaches.

Mushrooms will never convince me that I have seen that elusive nonentity, God. Are they aphrodisiacs? You tell me. Meanwhile I remain content with the ultimate earthly guide, Roger Phillips’ excellent Mushrooms (£12.99 on Amazon). Before you eat one, consult it.

Mushroom trips are not new. In 1486, a Dominican friar noted that potent mushrooms, the “flesh of the gods”, were being served at the coronation of the Aztec ruler. Statues carved like mushrooms go back thousands of years in Central America.

Sheldrake quotes a Franciscan friar there in the 16th century who watched people eat “little mushrooms” with honey. Some then danced, some wept, some sat and stared. Others seemed to see themselves dying or being eaten by a wild beast.

One theory about Hieronymus Bosch’s visionary paintings is that he had eaten mind-altering mushrooms and seen what he then painted.

Academia and banking eventually joined in. In 1938 a Harvard professor, Richard Schultes, visited a remote valley in Mexico and observed mushroom vigils among the local Mazatec people. His report interested the poet Robert Graves many years later, who shared it with a keen amateur mushroom-student, Gordon Wasson.

“Hello to all that”: Wasson was a vice-president of JPMorgan. He left the office and joined mushroom vigils in Mexico which he found to be “soul shattering”.

In 1957, he described them in Life magazine under a ringing subtitle: “A New York banker goes to Mexico’s mountains to participate in the age-old rituals of Indians who chew strange growths that produce visions.” It had to be better than snorting coke in a Wall Street loo.

In the 1990s, Dutch growers realised they could sell the relevant mushrooms without breaking the law. By 2004 London’s Camden Mushroom Company was selling 100kg of hallucinogenic mushrooms each week, enough, Sheldrake computes, for 25,000 trips. The law then tightened, but home-growing kits can still be found on the internet.

Do fungi have minds? Here Sheldrake and I part company. He inclines to credit them with memory and thought because of choices they appear to make when extending their filaments. There is sensible research here, but I would not apply mental language to the fungi involved in it.

We are said to share about 50 per cent of our genes with fungi, some of whom can live inside animals, but that does not make them sentient subhumans.

Some seem to react to experience and avoid matter that does not suit their growth. Since 2018, one has even been proven to insert a psychedelic drug and an amphetamine into visiting cicadas. The cicadas’ rear ends then disintegrate.

As so many fungi are almost invisible, much remains to be learnt, but I doubt if it will justify Sheldrake’s phrase “mycelial minds”. We have yet to find a ‘shroom with a view.

Meanwhile fungi are being co-cultivated with bacteria to produce antimicrobial compounds. Might they help in the war on Covid? Statins that lower cholesterol are already being extracted from fungi with filaments.

For gardeners, fungi are being marketed as “mycorrhizals” and recommended for packing round the roots of newly planted trees and shrubs. They encourage a denser growth of new roots because they make water and nutrients more accessible in the soil. They work well, I find, and help many long-term shrubs to establish, including magnolias, but they have to be used while still fresh.

Packagers do their best, but I prefer to use fresh leaf mould in new planting holes as its mycorrhizal contents are in prime condition. Take a plastic sack with you and scrape some leaf mould into it if you go on an autumn walk in a beechwood.

Despite all this benign activity, I never risk picking and eating an uninvited mushroom. Those fluted pink undersides are not necessarily safe. Last week, a semi-ring of shaggy mushrooms appeared in the lawn near my best bed of dahlias. Two nights later, they had been chewed down and reduced to the base of their stems.

Can mind-changing mushrooms make squirrels hallucinate? I am watching for signs of crazy tail-chasing in the grass between my avenues of pears.

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