Are psychedelic mushrooms getting stronger…?
The topic of psychedelic mushrooms getting stronger was recently raised in the psychedelic media circles and would have us believe they are. A recent article published on WIRED titled “Psychedelic Mushrooms Are Getting Much, Much Stronger” opens with a cautionary tale of how strong some mushrooms can be. However, there is more to this story than they acknowledge. Journalist Mattha Busby, in examining an emerging culture of well-informed cultivators, reveals a shift away from a cubensis-centric cultivation space to experimentation with new species. Armed with access to high-quality analytical and genetic equipment, these citizen scientists are helping shift Psilocybe cultivation in an interesting new direction.
Over the past few decades, cultivation techniques have improved, and with that, so have the levels of psilocybin found to be present within the mushrooms grown. In a landmark paper from 1982, Bigwood and Beug published results demonstrating how the substrate used for cultivation can significantly affect the amount of tryptamine production, with a fourfold variation in potency in cultivated specimens and a tenfold variation in potency from wild specimens. Variations in alkaloid production are thought to stem from changes in physiology, and as a consequence of their substrate and habitat, or the conditions under which they are grown if cultivated. When cultivating mushrooms, it’s a simple equation, but certainly not a new idea: greater nutrient inputs will result in greater potency outputs. Cultivated psilocybe may be getting stronger, but mostly because of a better understanding of the mushrooms' nutrient needs.
Foragers in Australia looking for Psilocybe subaeruginosa frequently report similar anecdotes, confirming that forest specimens are typically weaker than those grown from urban woodchip beds. This is a harm reduction narrative in Australia that we are used to, with most foragers having anecdotal stories of getting caught out—i.e., “Timmy! That was NOT a microdose!”
Another interesting development is the appearance of potency competitions, a case of who can grow the most potent mushrooms. While there has been a culture of striving for more potent cultivars for the past couple of decades, what is important to note is how these competitions are misleading; they don't give a true representation of the potency of a given cultivar, let alone a species. While these competitions do allow for community education, and some interesting comparisons, what we currently lack is a baseline figure of the potencies of species, or cultivars, grown across the same substrates and environmental conditions, to give us accurate breakdowns of average potency, and expected variation to account for any changes due to physiology.
Photograph of Psilocybe mexicana by Roger Heim. The early days of Psilocybe cultivation focussed on Psilocybe mexicana and other species collected by Roger Heim in Oaxaca in 1956
Psilocybin and psilocin are produced via the Psilocybin Gene Cluster (PGC), a part of the DNA that includes four genes that code for the biosynthetic enzymes–PsiD, PsiK, PsiM, PsiH–responsible for their biosynthesis. This part of the DNA is highly conserved, meaning it barely changes, and has been shown to be identical across most cultivars of P. cubensis (McTaggart et al., 2023) - i.e a cube is a cube, and even PE is just a cube, although notably, P-envy does have some allelic differences.
Research is starting to give us a better understanding of how the Psilocybin Gene Cluster changes between species (Bradshaw et al. 2024, McTaggart et al. pre-press 2023, McTaggart et al. 2024, and an upcoming publication from the Entheome Foundation), revealing the potential for differences in tryptamine production, including Psilocybin, in other parts of the genus psilocybe. Notably Section Zapotecorum, and Section subaeruginosae.
Those closely watching the psilocybe cultivation space lately will have noticed an ever-growing interest in collecting and cultivating novel species, including creating hybrids of very closely related species. Observers will also observe an increased understanding of fungi breeding, and an appreciation for the subtleties of the tetra-polar mating system. As we move away from a cultivation space that is very cubensis-centric, cultivators are exploring species that have a demonstrated higher tryptamine production, and while some of these are hybrids, it is important to note that the breeding is not responsible for the increase in potency, they are just naturally potent.
Foragers from Australia and Aotearoa have the benefit of experience in this regard, having an appreciation for marked increased potency between species and populations of those species. This shift towards exploring more potent species is gaining momentum in other regions, such as the United States. However, due to variations in climate, legal restrictions, and local knowledge, the foraging experience can differ significantly. For instance, in the Pacific Northwest, foragers often encounter species like Psilocybe cyanescens and Psilocybe azurescens (now known to be conspecific with Psilocybe subaeruginosa), which have a reputation for higher potency, while in parts of Europe, species like Psilocybe semilanceata (Liberty Caps) are more common. These global differences emphasize the importance of understanding local species, as potency can fluctuate widely based on geography and conditions.
Some species, though, didn't evolve their Psilocybin Gene Cluster but borrowed the technology via horizontal gene transfer. By inhabiting the same ecological niche and via some bacterial trickery, a natural form of gene editing can allow some species to borrow tricks from neighboring species. We refer to this as Horizontal Gene Transfer, which is how Panaeolus cyanescens came to obtain their version of the Gene Cluster. Because various Panaeolus species didn’t evolve their ability to produce psilocybin, they may potentially lack any regulation genes that limit psilocybin production, hence Panaeolus cyanescens currently dominating many of the competitions for their potency!
What is important is the ongoing harm reduction narrative around caution with dosing - ideally, knowing which mushroom species, which cultivar, and how others have reacted to the batch.
In conclusion, while the potency of Psilocybe mushrooms may appear to be increasing, much of this perception stems from advancements in cultivation techniques and the selection of cultivars that perform better in artificial environments. It's important to approach such claims with caution, as many factors, such as substrate, and species, contribute to variations in psilocybin production. Additionally, competitions and sensationalized media stories may misrepresent the actual potency of these mushrooms, further highlighting the need for accurate information and responsible use. As our understanding of psilocybin genetics deepens, the focus should remain on harm reduction, ensuring that individuals are informed about the specific species, cultivation methods, and potential effects of the mushrooms they are consuming.
Written by Caine Barlow
