Mushrooms are the fruiting body of a fungus, the part of the fungi that typically grows above ground or on a food source – more about that later. You might be interested to know if mushrooms have roots, and if not, how they receive the nutrients and water necessary for their growth.
Almost everything that grows comes from the Kingdom Plantae and has roots. Mushrooms are from the Kingdom Fungi, and as such, don't have roots. Instead, they have a root-like structure called MYCELIUM.
Fungi are heterotrophs; they capture energy from their surroundings to grow.
Table of Contents
What is Mycelium?
Picture a mushroom growing; anything above ground is the flower or the fruit. Below-ground is the root system, the mycelium.
The mushroom is one single part of the fungi; it is the host for the spores that enable it to reproduce.
Thousands of microscopic spores travel on wind currents and land on appropriate substrates. In ideal conditions - usually moist and humid - the spores will germinate.
Each spore grows of fine thread called hyphae, which creeps across and into the host.
Hyphae release chemicals to dissolve the food. The hyphal tips excrete enzymes to break down the surrounding substrate to digestible size to absorb into the cell wall; this is the beginning of the mycelium and how it gains energy.
Each individual cell branches out as it grows, forming a vast mycelial network. In some species, they cover several miles.
The body stores nutrients and other essential compounds. When it has accumulated enough and conditions are favorable, the mycelium 'fruits' producing the mushroom above ground.
To see the growth in action, roll a log over when on a forest walk. On the underside, the white, mold-like deposits are a stage of mycelium formation.
Are Mycelium Important?
Mycelia are a dense mass of filaments of tissue (hyphae) invaluable to the growth of all members of the fungi kingdom, not only mushrooms.
Mycelium reaches out to other plants across vast distances to form a mutually beneficial communication network. The exchange of nutrients and sugars occurs through the filament threads.
It is a system somewhat jokingly referred to as the Wood Wide Web - and helps maintain the health of the entire ecosystem.
Reduces Invasive Species
As mycelium grows, they develop enzymes and metabolites that protect themselves, the mushroom, and the host substrate from harmful pathogens.
It is a defense mechanism that increases the nutritional and medicinal value of the mushroom.
Other important features of mycelium include:
- They create a fertile soil environment as they act as a decomposer/composter of organic matter.
- They remove damaging toxins from soil, such as pesticides, chlorine, and more harmful industrial poisons.
- They form a solid structure within the soil that reduces the possibility of erosion.
Types of Mushrooms
There are 3-primary groups of mushrooms. The first type proliferates by feeding on a dead host, the second attacks a living host, and the third survives by co-operating with a living host.
Saprophytes are the most common type of mushroom that grows on decaying organic matter. They are known as scavenger mushrooms as they extract CO² and other minerals yet give nothing back in return. Saprophytes do however clean up the remnant of the plant when it dies.
Many edible and medicinal mushrooms fall into this category.
They are fungi that form many spores, most of which scatter amongst nearby plant and animal remains.
Safe to eat saprophyte mushrooms include champignon, morels, raincoats, umbrellas, and cobwebs.
Harmful saprophytes include pig, helwell, and pale, spring, and white toadstools.
As their name suggests, parasite fungi latch onto living, often very healthy, organisms and drain nutrients from them. It can result in the death of the host, a catastrophe in agricultural situations. In these circumstances, the fungi will continue to feed on the dead, organic matter, thus becoming a saprophyte and aiding the decaying process.
When there is nothing else for the parasite to take, the mycelium will attack the nearest healthy host and repeat the cycle.
Some examples of parasitic mushrooms include:
Head mushrooms – prefer cereals such as wheat, barley, and oats, where the mycelium spreads in the soil and causes devastation of entire crops.
Ergot mushrooms – often found in wheat fields and are toxic to humans.
Rust mushrooms – so-called due to their orangey-brown color. Rust mushrooms primarily extract their required nutrients from cereals but also attack ferns and flowers.
Mycorrhizal mushrooms form an intimate symbiotic relationship with their host. In layman's terms, the fungus and the tree benefit each other.
The mushroom receives a perfect growing habitat. The plant shares its sugars and carbohydrates from photosynthesis, something the fungi cannot do. In return, the mushroom passes essential nutrients to the tree.
Mycorrhizal mushrooms can extend the plant's roots system 1000x while increasing its moisture and nutrient capacity.
Host plants include – oak, birch, beech, eucalyptus, willow, poplar, pine, and spruce.
Those mycorrhizal with edible fruit trees as host (apple, pear, apricot) tend to produce inedible mushrooms.
The most flavorsome, sought-after gourmet mushrooms tend to fall into this category; they usually carry the heftiest price tag.
Truffles are the most expensive, costing around $30,000per kg.
Porcine, matsutake, amanita, chanterelle, and bolete are also mycorrhizal.
It may seem odd to say that mushrooms do not have roots when you consider that in Latin, 'myco' means fungi, and 'rhiza' translates to root.
They can't use photosynthesis, so mushrooms rely on a network of threads called mycelium to consume and metabolize live and dead organic matter.
Mushrooms grow in close association with plants and trees, where they thrive in humidity and extract water vapor from the air.
They are invaluable in many ecosystems where the mycelium unlocks previously unavailable nutrients, improving the soil quality, and increasing the growth speed and health of the host trees and plants.