In 1942 mycologist Elise Wakefield published a description of a curious mushroom she had observed growing in London’s Kew Gardens. Due to its similarity to a species known from the United States, it was placed in the genus Psilocybe, with the binomial name Psilocybe cyanescens. Wakefield took note of the mushroom’s apparent bluing reaction at the time. Still, it would be another 20 years before the cause of the bruising in this species was identified—the oxidation of the compound psilocin.

As conversations around magic mushrooms become more common and increasingly positive, there has been a growing interest in the number and variety of Psilocybe species. Of these, a few have always been iconic. Psilocybe cubensis aka “Gold Top,” Psilocybe semilanceata known as the “Liberty Cap,” and Psilocybe cyanescens the “Wavy cap,” so-called because of its distinguishing feature: a sinusoidal wavy top.

Psilocybe cyanescens: An Introduction to Wavy Caps

Psilocybe cyanescens is more commonly known as “Wavy cap” for the very delightful reason that the caps feature an undulating wave. Of the wood-inhabiting group of Psilocybe, P. cyanescens is perhaps the most well-known and most foraged. This species is well known for its potency, yet its growth patterns also make it quite remarkable; wavy caps thrive in mulched wood chip beds. Photos from various websites show huge flushes in wood chip beds from the UK and Northern America, often hundreds within a single patch.

Wavy caps are not as well known as “Gold Tops” or “Liberty caps.” However, interest in “Wavy Caps” has increased over the past decade, thanks in part to Paul Stamets and his book Growing Gourmet and Medicinal Mushrooms, in which he describes how easily they grow in wood chipped garden beds. They are a common species in the US, preferring the Oceanic climate of the Pacific Northwest and occurring along the West Coast, from Vancouver down to California. They are also very common in the UK and Europe, where they are now believed to be an introduced species.

Psilocybe cyanescens is closely related to the similarly potent species, P. azurescens and P. allenii from the Pacific Northwest of the United States, P. subaeruginosa from Australia, and Psilocybe weraroa from New Zealand.

It is worth noting that harvesting Psilocybe cyanescens is a potential felony enforced by local law enforcement agencies in most places worldwide. The cultivation of P. cyanescens is also illegal in many countries and is considered “manufacture.” Those who choose to partake in foraging or choose to cultivate these unique mushrooms take upon themselves considerable legal risk in this era of prohibition.

What Do cyanescens Look Like?

Psilocybe cyanescens is well-known for its distinctive caramel brown wavy cap and white stem. These notable characteristics are essential to remember—mushrooms in the genus Psilocybe spp. share many features, especially those that fall within the group that includes P. cyanescens. So, it can be difficult to tell certain species apart without taking a closer look. The wavy cap is often used to distinguish P. cyanescens from the closely related species P. azurescens “flying saucers” and P. allenii. This feature sometimes confuses enthusiasts in Australia, as P. subaeruginosa often has a wavy cap. There are no reports of P. cyanescens on the continent to date.

Psilocybe cyanescens caps are, on average, between 1–2.5 cm (0.5 to 1 inch) in diameter. They are convex when young, lifting to become wavy in maturity. The caps are often caramel brown, but the color fades to pale bluff, yellow, or cream as moist cap tissue—hygrophanous tissue—dries out. The gills (lamellae) are adnate, which describes how each gill is attached to the stem. Adnate gills are connected to the stem slightly above the bottom of the gill, creating a subtle arching shape. The gills are white to light brown becoming brown to dark purple-brown as they mature.

Unlike P. azurescens, “Wavy Caps” do not have a prominent umbo, the pointed tip at the top of some mushroom caps. But, wavy caps share the same smooth, viscous appearance when moist. Their caps are sticky to the touch thanks to an outer gelatinous layer called a pellicle, which is removable if the cap is broken carefully. The P. cyanescens mushroom forms within a cobweb-like partial veil that peels away as the cap matures and expands, leaving an annular zone around the stem that remains sticky and often turns purple-black because of spores.

The stem is fibrous, white when young, becoming grey-brown as they mature. The odor and taste are farinaceous, “flour-like”. The rhizomorphs of P. cyanescens can help identify this species. Rhizomorphs are the root-like structures that extend from the base of the stem—they are composed of matted mycelium and resemble thick fibers. They are strong enough to lift parts of the substrate when one lifts the mushrooms from their environment.

All parts of the mushroom—the cap, gills, stem, and rhizomorphs—generally bruise blue or blue-green from inury. After drying, this color remains visible, becoming more grey-blue. This staining is often most noticeable on the stem, especially on younger specimens that still have white stems. The bruising is due to the oxidation of psilocin. Psilocybin, the precursor to psilocin, cannot be oxidized directly but through enzymatic action is converted to psilocin at injury sites and is then oxidized.

Where to Find Psilocybe cyanescens

The Wavy Cap is a saprophytic mushroom often found growing on rotting wood and debris in a variety of forest types, but also very common in parks and urban gardens growing amongst the wood chip mulch. Saprophytic mushrooms obtain nutrients from decaying material—decomposing wood chips, for the Wavy Cap. They can also be found growing on sawdust or from soil containing wood chips or bark; they are rarely found growing alone, more frequently gregarious, sometimes in clusters consisting of many (or hundreds!) fruit bodies. This species is a cold-loving species, with fruiting triggered by a drop in temperatures. Wavy Caps fruit from October to December.

Wavy caps are a cold-loving species found in the northern hemisphere, they favor an oceanic climate. Their distribution includes the United Kingdom, parts of Europe including the Netherlands, France, Czechoslovakia, and Germany. They are also found in the Pacific Northwest in North America, along the west coast from Vancouver to California. They were not known to occur in eastern North America until recently.

Although the species was first named and described from a collection in the United Kingdom (in “New or interesting British fungi” by Dennis & Wakefield, 1946), its true origins are likely the United States. Elise Wakefield knew about Psilocybe cyanescens for many years before publishing her first description of the peculiar fungi; she started collecting them in 1910. She usually found them during autumn in the woodland parts of Kew Gardens, located in southwest London.

Wakefield, however, did not find them elsewhere, except on one occasion in a neighborhood close to Kew Gardens, growing from some rotting wood. Wakefield noted the “decided indigo-blue color which develops on both stem and pileus when handled”, comparing it to the American species P. caerulescens Murr.

Kew Gardens in southwest London is a significantly important botanical garden. It contains the “largest and most diverse botanical and mycological collections in the world.” Plants traveled from all areas of the globe to make it to the gardens, and plenty of fungi joined the voyage. Botanical gardens are often filled with fungi introduced from other countries, intentionally or not. Aseroe rubra and Leratiomyces ceres from Australia are two additional species that may have been introduced to Kew Gardens in a similar manner to P. cyanescens. Incidentally, the former two fungi are also common in the United States.

How Potent are Wavy Caps?

The considerable potency of P. cyanescens makes it a highly sought-after species, especially with underground cultivators. The mushrooms are not only popular with those looking for more substantial experiences but for those who wish to use them for microdosing as well. Yet, with the wavy cap, it’s possible that not all is what it seems.

Read: Liberty Caps are Among the Most Potent Magic Mushrooms

The chemistry of P. cyanescens was first reported in 1962 by Tyler and Stuntz. Despite the fungi’s heavy-handed reputation, its potency can be quite variable. Current thought suggests that different growing substrates may contribute to variations in alkaloid concentrations in the fungi. Beug and Bigwood, for example, found the psilocybin and psilocin content of dried P. cyanescens from the Pacific Northwest to be between 0-1.68 percent psilocybin, and 0.06-0.96 percent psilocin. They published their analysis in 1982.

Stijve and Kuyper, in a 1985 analysis of P. cyanescens from Europe, found 0.1-0.8 percent psilocybin, 0.04-0.47 percent psilocin, and 0.01-0.03 percent baeocystin. In 2003, Stríbrný and others published a paper reporting specimens of P. cyanescens from the Czech Republic contained 0.13-1.84 percent psilocybin and 0.28-1.81 percent psilocin.

The wood-loving group of Psilocybe that includes P. cyanescens is known to contain high levels of psilocybin and various indole alkaloids. Psilocybe cyanescens in this regard is no different. Psilocybe cyanescens have been shown to contain many different indole alkaloids, including psilocybin, psilocin, and baeocystin, aeruginascin, and monoamine oxidase inhibitors.

Wavy Cap identification & Wavy Caps Look-alikes  

Care should be taken when foraging for P. cyanescens as there are many species that look similar which should be treated with caution. The most likely to cause concern are species from the genus Galerina, which can be deadly by virtue of the fact they contain amatoxins—poisons unique to fungi.

After ingesting amatoxins, some people may feel ill within a couple of hours, then recover after a few hours, while others may experience no symptoms at all. During this time, the amatoxins begin causing damage to the liver and kidneys. Without treatment, approximately two days after the poisoning, individuals start to feel weak, then very ill, and soon after that, experience organ failure.

Galerina spp. resemble young specimens of P cyanescens with their caramel-brown cap, but have a brown stem with an annulus. The rust-brown spore print is helpful in identifying species from this genera. They are poisonous and potentially deadly as they contain amatoxins, the same toxins found in Death Caps, properly known as Amanita phalloides.

Other species considered lookalikes are from the genera Cortinarius, Hypholoma, and Leratiomyces. Cortinarius spp. are also reported as lookalikes, some species have a blue coloring that fades over time, resembling blue bruising. Some have brown caps that resemble Psilocybe spp.  Cortinarius spp. also have rust-brown spores, and some can be very poisonous, resulting in liver and kidney damage.

Less poisonous but also of note are Hypholoma spp. which can also look similar to Psilocybe spp, but they grow in dense clusters, which is uncharacteristic of Psilocybe. They tend to have brown caps with white stems and a purple-black spore print, and some can be poisonous. Leratiomyces ceres, aka Woodchip cherry, has an orange-red cap and retain their veil remnants at the margin and on the surface. They have greyish gills, and their stem is orange-red or pale yellow. They have a purple-black spore print and are poisonous.

How To Identify P. cyanescens: Spore Prints, Bruising, and Other Features

As you can see, Wavy Caps have a fair number of posionous lookalikes—and it only takes one mistake to end up in quite the pickle. Proper idenitification of Psilocybes—particularly when wild foraging—is absolutely essential. To identify psilocybe mushrooms, there are two vital questions to ask:

• Does it bruise blue?
• What color are the spores?

All Psilocybe bruise blue; in fact, it’s one of their most discernable characteristics. Bruising may take little time to appear in some species; some species barely bruise, but species like the Wavy Cap bruise readily. Next, making a spore print is a helpful mushroom identification technique. But, its important to avoid making a guess about a species’ identity based on a spore print or blue bruising alone. The presense of both, along with observations about other psilocybe characteristics, are needed to make a safe identification.

To make a spore print, you simply remove the cap of a harvested mushroom and place it face-down under a cup on a piece of foil. Within 24 hours, spores will have fallen onto the paper in a unique pattern. (Learn the specifics on making a proper and safe spore print here.) Psilocybe spores should be purple-black in color. In addition to purple-blue spores—a featured shared by some poisionous lookalikes mentioned above—it’s also important to look for other discernable features, like a separable pellicle and fibrous stems. Post photos to Shroomery for identification help or local Facebook Psilocybe groups.

Another important adage? If in doubt, throw it out. As well as getting to know the species you are looking for, get to know the potential look-alikes. If you think you have been poisoned, phone your local emergency hotline. You can access information about poisoning by calling your local poisons hotline.

How to Grow cyanescens Outdoors

Psilocybe cyanescens grow on various hardwoods such as Alder chips (Alnus rubra) or other woody mulches. They will readily grow in urban garden beds mulched with a variety of wood chips. Spore prints and spore syringes are readily available through underground communities on forums like Shroomery and online distributors. Cultivators can also use simple methods of tissue culturing onto cardboard or burlap. Keep in mind the cultivation of P. cyanescens is illegal in many countries and considered “manufacture.”

Wavy caps grow readily within mulched garden beds; they like shady areas with good moisture. They are known to grow near rhododendrons, rose bushes, and azaleas. This is not uncommon with the wood-loving psilocybes, with P. azurescens, and P. subaeruginosa, also known to do well in urban environments. The methods the Aussies use to make subaeruginosa wood chip beds will work perfectly for wavy caps!

P. cyanescens can grow on various plant or wood-derived substrates: compressed sawdust blocks, fire pellets, or the free garden mulch from your council refuse area. The same techniques used to grow mushrooms, such as Stropharia rugosoannulata or Lepista nuda, as described in Stamets’ book Mycelium Running, can be adapted to grow a variety of wood-inhabiting species. They can be started in small batches, then expanded, and in time be used to set up garden beds.

Psilocybe cyanescens Effects: Wood-Lovers Paralysis

Psilocybe cyanescens comes with a word of caution—as with P. azurescens and related species, wavy caps may cause a phenomenon known as Wood Lovers Paralysis (WLP). In recent years there have been increasing discussions in forums such as The Shroomery, and Facebook groups dedicated to identifying Psilocybes that may produce this interesting effect. To date, the effect has been reported from wood-inhabiting species of Psilocybe mushrooms such as P. azurescens, P. cyanescens, P. allenii, and P. subaeruginosa. The reports describe how some people experience a loss of muscle strength and motor control that can persist into the following day. There is currently no satisfactory explanation, and a few theories abound, but a compound called aeruginascin is touted as a possible culprit.

Aeruginascin is very similar in structure to psilocybin, except it contains a third methyl group.  One of the main theories is that if aeruginascin undergoes the same dephosphorylation, as in the conversion of psilocybin to psilocin, the resulting compound behaves similarly to bufotenidine. Bufotenidine is a toad venom that is known to cause paralysis. Due to their chemical structure (both contain a third methyl group), neither compound is able to cross the blood-brain barrier and are probably confined to the peripheral circulation in the body, where they affect tissues containing the appropriate receptors.

This paralysis should not be confused with the overwhelming effects of a strong dose of psilocybin, as it can occur at relatively low levels of psychedelic intensity. WLP is a distinct physiological effect. The effect is known to be temporary, usually wearing off after 24 hours, but for the unprepared, it can be an anxiety-inducing experience.