In workshops and teaching events we’re often asked, “Do mushrooms have roots?” The simple answer is ‘No’, but there’s a lot more to it than that! Take a read through this article to learn more about the biology of how mushrooms grow
“Do mushrooms have roots?”
The answer is ‘No’, but they do have a wonderful rootlike structure called mycelium.
Roots are primarily applicable to the plant kingdom. Mushrooms, which are part of the fungi kingdom, grow out of mycelium.
In the video below we show an example of what mycelium looks like while it is growing in a petri dish.
In the video you can see a white, fuzzy disk-shaped growth in the petri dish. It may look like some forms of mold you’ve seen in your life. Mold is ultimately mycelium, and the video provides a closer look.
Do mushrooms have roots? Information on mycelium
Mycelium is the vegetative body for fungi that produce mushrooms and, in some cases, species of fungi that never produce a mushroom. When compared to a plant, mycelium is the root system and the mushroom is the flower. When a spore lands on an appropriate substrate under suitable conditions, that spore will germinate. The germination is the beginning of the mycelium from a single meristematic cell. Mycelium consists of the growing ‘stem’ cells of the fungus. Fungi are heterotrophs so they must attain energy from their surroundings, like humans. Mycelium grows by releasing enzymes from the hyphal tips of the mycelium to digest the surroundings and then absorb the nutrients. The cells will eventually branch and continue to branch as it grows to build a vast, filamentous mycelial network.
Interestingly enough, many believe that mycelium is a very valuable material in helping to replace petroleum-based products. As the Journal of Unsolved Questions points out, “Fungal material is renewable, compostable under certain conditions (moisture and the presence of other organisms), fire resistant, moldable, free from volatile organic compounds (VOCs), dyeable and vegan.”
There are already some companies working with mycelium to create new options for common goods, like leather and packing materials, for instance.
Do mushrooms have roots? A look at how we get our mycelium to grow
First, we grow mycelium in a petri plate like you saw in the video. Then, we take a slice of the mycelium and we put it in a bag. In the video we display a plastic bag filled with grain that the mycelium grows down into. The mushrooms will then grow from the white mycelium that has spread through the grain.
The mycelium grows in the substrate and breaks down all the nutrients of the substrate. Those nutrients are then incorporated into the body of the mycelium. Then, once the conditions are just right, the mycelium fruits a mushroom.
In the video we display what this process looks like once the mushroom has grown from the substrate. We use a bag of lion’s mane mushrooms. In the bag you can see the sawdust substrate and the white mycelium. The mushroom itself is fruiting right out of the bag.
Once the fruited body of the mushroom is picked from the mycelium, the mycelium remains intact. It continues to grow and eat the substrate, and the bags of mycelium shown in the video will eventually fruit again within a couple of weeks.
Additionally, we create holes in our bags so the mushrooms can fruit out of them, leaving the remaining mycelium in the bag.
A growing analogy that compares the plant kingdom with the fungi kingdom
The mushroom is like an apple and the mycelium is like the whole plant structure: the leaves, bark, steams, roots, etc. Those all help play a similar role in the trees lifecycle as the mycelium does for fungal lifecycle. The mushroom is just the fruiting body. It comes and goes and it can be harvest like an apple. However, the mycelium, much like a tree, will stay, remain growing and producing fruit when the conditions are correct.
As you may have noticed, mushrooms can pop up really quick after a rain in the spring or summer because the mycelium is always there, ready to produce fruited bodies.
So in conclusion, do mushrooms have roots? No, but they do have a similar system that plays a roll like roots do. This system is called mycelium and gathers nutrients and supports the formation of fruiting bodies.
And one final interesting fact… The largest living organism in the world is mycelium of a honey fungus that exists in the Pacific Northwest of the United States, specifically in the Blue Mountains of Oregon. This fungal network spans over 2,400 acres. Scientists have estimated that the mushroom mass is around 2,400 years old, although some others claim that it can be as old as 8,650. If this latter estimation is true, not only would this mycelial mass be the largest living organism, it would also be one of the oldest on the planet.