Mushrooms: Nature's Magical Mystery

Mushrooms are a lot like plants, but they are not plants or animals. They are part of the Fungi kingdom. They emerge from the ground or trees and have stalks, gills, and caps. Mushrooms produce spores, which are almost as fine as smoke, and these spores are used to identify the mushroom. Some mushrooms are hallucinogenic, like Psilocybe mushrooms, commonly known as magic mushrooms. Mushrooms play an important role in nature and to humans, as they are used in horticulture and cuisine.

How mushrooms grow and develop

Mushrooms are unique organisms that are neither plants nor animals. They are members of the kingdom Fungi, which is incredibly biodiverse, containing up to 12 million species. The mushrooms we are most familiar with, the classic cap-and-stem varieties, are members of the phylum Basidiomycota. All mushrooms in this group, including jelly fungi, puffballs, and porcini, produce their spores outside of club-like cells called basidia.

A mushroom develops from a nodule, or pinhead, called a primordium, which is typically found on or near the surface of the substrate. It is formed within the mycelium, the mass of thread-like hyphae that make up the fungus. The primordium enlarges into a roundish structure of interwoven hyphae roughly resembling an egg, called a "button". The button has a cottony roll of mycelium, the universal veil, that surrounds the developing fruit body. As the egg expands, the universal veil ruptures and may remain as a cup, or volva, at the base of the stalk, or as warts or volval patches on the cap. Many mushrooms lack a universal veil, and therefore they do not have a volva or volval patches.

Once the primordium has enlarged into a button, the mushroom can rapidly pull in water from its mycelium and expand, mainly by inflating preformed cells that took several days to form in the primordia. This is why mushrooms seem to appear overnight, growing and expanding rapidly. However, all species of mushrooms take several days to form primordial mushroom fruit bodies.

Mushrooms grown outdoors take cues from their environment to begin forming. Changes in humidity, temperature, and moisture are major determining factors for when mushrooms grow, and each species of mushroom has a particular preference. For example, in the temperate Northeastern US, most edible mushrooms fruit between spring and fall (May to October), depending on good rainfall. On the other hand, on the Pacific Northwest coast, mushroom season peaks between August and December.

How to identify mushrooms

Mushrooms are a type of fungus with a stem (called a stipe) and a cap. Fungi are incredibly diverse and different species can look very similar, so it can be challenging to identify mushrooms accurately. Here are some detailed instructions on how to identify mushrooms:

First, note the substrate, or the material that the mushroom is growing from. Some mushrooms grow in soil, some on living trees, and others on rotting wood. Knowing the substrate can provide insights into the mushroom's ecology. For example, mushrooms in the Pleurotus genus, often called "oyster mushrooms," typically grow on wood or debris.

Next, examine the underside of the cap, where the fertile surface for spore formation, known as the hymenial layer, is often located. Observe the gills or ridges under the cap. Some gills end abruptly where the stem (stipe) begins, while others run down the length of the stem. Some gills fork into a Y-shape, and some alternate between full-length and partial gills. Additionally, some mushrooms, like the oyster mushroom, have small "teeth" or spines hanging from the underside of the cap instead of gills.

Another important characteristic to note is the spore colour. By placing the cap of a fresh mushroom on a sheet of paper and waiting a few hours, you can obtain a spore print. Many field guides are organised by spore colour, making it a crucial trait for identification.

Beyond these physical characteristics, some mushrooms exhibit chemical reactions when exposed to certain substances, while others are distinguished by microscopic features. Additionally, the smell and taste of a mushroom can be indicative of its type. For example, chanterelle mushrooms have a slightly fruity or flowery scent.

It is important to consult a highly-rated guidebook specific to your region when attempting to identify mushrooms. Online resources like the iNaturalist algorithm can also assist in narrowing down the identification to the genus or family level. However, it is recommended to seek expert advice from local mushroom clubs or arboretum staff for accurate identification.

The different parts of a mushroom

Mushrooms are unique organisms that are neither animals nor plants. They are a type of fungus with a complex structure that comprises around 20 distinct parts. The mushroom itself, also known as the fruiting body, is the fruit of the fungus, and it exists only for a short period. Its primary function is to spread spores at the end of the mushroom's life cycle.

The most recognisable part of a mushroom is its cap, also known as the pileus. The cap is the topmost structure of the mushroom and can be smooth or covered with scales or teeth. The shape of the cap varies from species to species, with some having a spherical dome shape, while others, like lion's mane mushrooms, have "teeth" or shaggy hair-like structures. The colour of the cap can also vary, ranging from thin brown to colourful and beautiful. The cap holds the gills, pores, and ridges, and some mushroom caps may also have teeth-like structures called "teeth". These teeth perform the same function as gills, dispersing spores.

Beneath the cap are the gills, which are separate parts that can be picked off. They are located on the bottom side of the cap and are responsible for dispersing the spores. The gills can be attached to the stem or free, where they never reach or attach to the stem. They can also have various forking or branching patterns.

The stalk or stem may be central and support the cap in the middle, or it may be off-centre or lateral. Some mushrooms, like puffballs and truffles, lack a stalk but may have a supporting base. The stem can also have a ring, or annulus, which is a remnant of the partial veil that covers the gills during development.

The mushroom's fruiting body develops from a small nodule called a primordium, which enlarges into a round structure called a "button". This button has a universal veil, a cottony roll of mycelium that surrounds the developing fruit body. As the mushroom expands, the universal veil ruptures and may leave remnants such as a cup-shaped structure called a volva at the base of the stalk.

Beneath the surface, mushrooms have a complex network of minuscule hyphae called the mycelium, which is analogous to a plant's root system. The mycelium absorbs nutrients and connects with other fungi. It forms the majority of the fungus and is vital for its growth and reproduction.

Mushrooms as parasites

Mushrooms are a type of fungus that can develop in a variety of ways, including through parasitism. Parasitic mushrooms feed on other living organisms, including insects, trees, and other fungi. They can be classified as either true parasites or saprotrophs, depending on whether they feed on living or dead tissue. Some parasitic mushrooms are also saprotrophic, meaning they can feed on both living and dead matter.

One example of a parasitic mushroom is the lion's mane mushroom, which grows on dead trees and logs, as well as from wounds on living trees. Because of its ability to feed on living trees, it is considered both saprotrophic and parasitic. Lion's mane mushrooms have a unique, shaggy appearance and are known for their medicinal properties. They have been shown to improve cognitive abilities, boost the immune system, and reduce inflammation.

Poplar mushrooms are another example of parasitic fungi. These large, edible mushrooms are found in New Zealand and Australia and grow on various trees. They are classified as semi-parasitic and typically grow on weak or unhealthy trees, causing heart rot that eventually kills the tree. Poplar mushrooms are prized for their culinary applications, with a meaty texture and savoury, umami flavour.

Elm oyster mushrooms are also considered parasites, although their classification is uncertain. They are often found growing high up in branch scars and wounds on living elm and box elder trees. While they are not true oyster mushrooms, elm oysters are edible and medicinal, with similar culinary and health benefits to lion's mane mushrooms.

In addition to trees, some parasitic mushrooms target insects. For example, the caterpillar fungus infects a specific species of caterpillar, kills it, and then uses the nutrients to produce a small mushroom that grows out of the caterpillar's head. This type of mushroom is highly valued for its health benefits and is considered a delicacy in certain cultures.

Mushrooms as hallucinogens

Mushrooms are a polyphyletic informal group of fungi that contain the prodrug psilocybin, which turns into the psychedelic psilocin upon ingestion. Psilocybin is a hallucinogenic chemical found in certain mushrooms, commonly known as magic mushrooms or shrooms. Eating mushrooms that contain psilocybin can lead to a variety of effects, ranging from euphoria to hallucinations. Some people use psilocybin as a recreational drug, as it can provide feelings of euphoria and sensory distortion that are common to hallucinogenic drugs, such as LSD.

Psilocybin works by binding to and activating serotonin receptors in parts of the brain, such as the prefrontal cortex and amygdala. These parts of the brain affect mood, cognition, and perception. Hallucinogens also work in other regions of the brain that regulate arousal and panic responses. Psilocybin may cause visual or auditory hallucinations and distort how some people who use the drug perceive objects and people in their environment. The effects of psilocybin mushrooms come from psilocybin and psilocin. When psilocybin is ingested, it is broken down by the liver in a process called dephosphorylation, resulting in the compound psilocin, which is responsible for the psychedelic effects.

The dosage of psilocybin-containing mushrooms depends on the psilocybin and psilocin content, which varies significantly between and within the same species. Psilocybin content is typically around 0.5% to 1% of the dried weight of the mushroom, with a range of 0.03% to 1.78%. Psilocin is also often present in the mushrooms, with a range of 0% to 0.59%. Psilocybe cubensis, the most popular species, has been reported to contain 0.63% psilocybin and 0.6% psilocin, or about 1.2% of psilocybin and psilocin combined. Recreational doses of psilocybin mushrooms are typically between 1.0 and 3.5–5.0 g of dry mushrooms and 10 to 50 g of fresh mushrooms.

Microdosing has become a popular technique for many users, which involves taking less than 1.0 g of dried mushrooms for an experience that is not as intense or powerful but still recreationally enjoyable. A microdose of psilocybin mushrooms is about 10% of a recreational dose, and may be 0.1 to 0.3 g of dried mushrooms, taken up to three times per week. Microdosing is also used by some people who hope that it will improve mental health issues like depression, anxiety, and obsessive-compulsive disorder (OCD). However, research to date has not established that microdosing is safe or effective.

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