Mushrooms: Nature's Magical Appearance

Mushrooms are a type of fungus that can be identified by their macroscopic structure, which is typically a stem and cap. Many species of mushrooms appear to grow overnight, but this is a result of their rapid expansion by absorbing fluids. In reality, all mushrooms take several days to form their fruit bodies, which are less than two millimetres in diameter. Mushrooms can be cultivated, but they can also be foraged. However, it is important to be able to distinguish between edible and poisonous mushrooms, as consuming the wrong type can be deadly.

Mushrooms can take up to 18 months to appear

Mushrooms are fungi that develop from a nodule, or pinhead, called a primordium, which is typically found on or near the surface of the substrate. While many species of mushrooms seem to appear overnight, all mushroom species actually take several days to form primordial mushroom fruit bodies. The speed at which mushrooms appear is due to their rapid expansion by the absorption of fluids.

The primordium enlarges into a roundish structure of interwoven hyphae, resembling an egg, called a "button." This 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. Once the button stage is formed, 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.

The speed at which mushrooms appear can be influenced by various factors, such as body weight, metabolic rate, and whether the mushrooms are consumed on an empty stomach or with food. For example, if mushrooms are consumed with food, the gastrointestinal system may postpone the start of the process for up to an hour, depending on food intake, quantity of intake, and digestion time. On the other hand, consuming mushrooms on an empty stomach may lead to a milder sensation and help avoid abdominal pain or nausea.

While mushrooms can appear rapidly, the process of mushroom formation actually begins well before they are visible. From the initial formation of the primordium to the expansion of the egg-like structure, the development of a mushroom can take several days to over a month. In some cases, mushrooms may even take up to 18 months to appear, depending on environmental conditions and the specific mushroom species.

Many species appear to grow overnight

Many mushroom species seem to appear overnight, expanding rapidly in size. This phenomenon has led to the common expressions "to mushroom" or "mushrooming" and "to pop up like a mushroom". However, it takes several days for all mushroom species to form primordial mushroom fruit bodies. The initial growth stage is called the pin stage due to its small size. As they slightly expand, they are called buttons, reflecting their size and shape. Once these stages are formed, mushrooms can rapidly absorb water from their mycelium and expand by inflating pre-formed cells, giving the appearance of overnight growth.

The process of cultivating mushrooms involves drilling holes in logs and inserting impregnated dowels. The logs should be freshly cut from hardwood trees such as oak, beech, or maple, with a diameter of 10-15 cm and a length of 45-60 cm. After sealing the holes with wax, the log is placed in a shady spot, propped up with one end on the ground, and kept moist. It can take up to 18 months for mushrooms to appear.

Another method of cultivation involves using oyster mushroom spawn and straw. The straw is soaked in water overnight to ensure it is thoroughly damp, and then mixed with the mushroom spawn. This mixture is packed into a polythene bag and sealed. It is then left for six weeks in a damp, sheltered spot between 20-25°C. As the straw breaks down, the mushroom spawn colonises it, leading to the growth of mushrooms.

While the rapid expansion of mushrooms gives the appearance of overnight growth, it is important to understand the underlying process. The formation of the primordial mushroom fruit bodies and the subsequent expansion through water absorption are key steps in the growth of mushrooms. Cultivating mushrooms requires specific techniques and conditions, and the time for mushrooms to appear can vary.

Distinguishing between edible and poisonous mushrooms

Mushrooms are a diverse group of fungi that can appear in a variety of shapes, sizes, and colours. Many mushroom species seem to appear overnight, but in reality, they take several days to form primordial mushroom fruit bodies before expanding rapidly through fluid absorption. The delineation between edible and poisonous mushrooms is not always clear-cut, and some edible mushrooms may be unsafe for certain individuals due to allergies or sensitivities. Therefore, it is crucial to exercise caution and consult experts when identifying and consuming mushrooms. Here are some guidelines for distinguishing between edible and poisonous mushrooms:

Cap and Stem Colour: Avoid mushrooms with red caps or stems, as many red mushrooms are poisonous. Instead, opt for mushrooms with white, tan, or brown caps and stems.

Scales and Patches: Look for mushrooms without scales or patches on the cap. Poisonous mushrooms often have spots or patches of lighter or darker shades, which may appear as scaly spots.

Gills and Folds: Examine the gills or folds of the mushroom. Poisonous Jack O'Lantern mushrooms have true gills that end abruptly at the same spot along the stem. In contrast, the folds of Chanterelles run along the stem, ending unevenly at various points.

Stem Features: Check for the presence or absence of a ring or annulus around the stem. Many mushrooms have a partial veil that covers the gills, and remnants of this veil may form a ring or collar-like structure around the middle of the stem. However, some poisonous mushrooms lack a partial veil and, therefore, do not have a ring.

Texture and Feel: Touch and feel the mushroom to identify any sliminess or stickiness. For example, the Shaggy Mane, an edible mushroom, has a shaggy texture on its cap, while its toxic look-alike, the Alcohol Inky Cap, lacks this shaggy texture.

Diagnostic Traits: When collecting mushrooms, especially those with toxic look-alikes, it is essential to examine their internal structures. For instance, true morels have pitted caps and smooth, hollow stems, while False Morels have wavy, crumpled caps and nearly solid stems.

Spore Prints: Creating spore prints can help identify mushrooms. Place the cap gill-side-down overnight, and observe the powdery impression formed by the spores, which will reflect the shape of the gills, pores, or spines.

Regional Field Guides: Consult regional mushroom field guides or connect with local mycological groups to identify edible and poisonous mushrooms specific to your area.

Remember, no single trait will definitively indicate whether a mushroom is poisonous. Always exercise caution, consult experts, and refrain from ingesting any mushroom unless you are absolutely certain of its edibility.

How to identify mushrooms

Mushrooms are fun to identify and forage, but it is important to be careful as the wrong kind can be deadly, or at the least, very toxic. Even experts find it hard to identify mushrooms, so it is always good to have a second opinion.

Firstly, it is important to understand the basic structure of a mushroom. Most are basidiomycetes and gilled. Their spores, called basidiospores, are produced on the gills and fall in a fine rain of powder from under the caps. To identify these spores, you can make a spore print. Cut the stem off at the base of the cap and put the cap gills-down on white paper, with another piece of paper on top. Put a weight on top, like a book, and leave for about six hours. You are looking for a chocolate-brown or purple-ish spore print.

Secondly, it is important to be able to distinguish between edible and poisonous fungi. For example, the Shaggy Mane mushroom is edible, but it looks similar to the toxic 'Alcohol Inky Cap'. The Alcohol Ink Cap gets its name from its toxic component, 'coprine', which is highly reactive with alcohol. The Yellow Morel is another edible mushroom with a distinct appearance, but its poisonous look-alike, Gyromitra spp., contains a highly toxic and carcinogenic chemical called gyromitrin. The true Yellow Morel has a pitted cap and a smooth, hollow stem, whereas the false morel has a wavy and crumpled cap and a solid stem.

Thirdly, it is important to be aware of the different types of mushrooms and their characteristics. For example, the king oyster mushroom is known for its thick stem, whereas the black trumpet mushroom has a rich, smoky flavour.

Finally, it is always good to seek help from experts. There are many online forums and Facebook groups dedicated to mushroom hunting and identification, and it is always good to go on a mushroom walk with someone who knows what they are doing.

The different parts of a mushroom

Mushrooms are fungi that develop from a nodule, or pinhead, called a primordium, which is typically found on or near the surface of the substrate. The primordium enlarges into a roundish structure of interwoven hyphae 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.

The mushroom itself, also known as the fruiting body, has four primary structures: the cap, the gills, the stem, and the ring. The cap is the topmost structure of the mushroom, also known as the pileus. It can be smooth or covered with scales or teeth. The gills are 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 stem is a relatively large and sturdy cylindrical part that supports the cap of the mushroom. The ring may be skirt-like, collar-like, or merely the faint remnants of a cortina.

Beneath the surface, mushrooms have minuscule hyphae that make up mycelial networks that can spread out for miles. The mycelium is like a plant's root network that spreads over large distances underground to absorb nutrients and connect to other fungi. The mycelium makes up the majority of the fungus, and the mushrooms are simply the fruit it produces when it wants to reproduce.

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