Collaboration, Decisions, and New Technology: The Mysterious Power of Mycelium

Fundación Mar Adentro: Which mushroom characteristics can you also find in humans?
Gabriel Orrego: Mushrooms are curious, dynamic and genetically closer to us than to plants. Until a few decades ago, they were considered part of the plantae (plant) kingdom (plants). Fungi do not photosynthesize; they are heterotrophs and in this way are like us. They make decisions, organize themselves, they are social and thrive in communities or when they need to collaborate. They are good at entering symbiotic relationships with organisms from other kingdoms, doing so intimately with, for example, plants. They are symbiotic and know how to become parasites to insects or other animals. We have a lot to learn from them, for example, about mycorrhizae or the network of mycelium in the forest and the stronghold that it maintains, in being like a large organism and not thinking as individuals, but more so in the importance of an ecosystem’s health.

What are these symbiotic associations like?
Mycorrhizae are formed by a symbiotic relationship between fungi and plants, it is something very ancient that can be found in all of nature. Even before the first tree, the first flowers and fruits there were other plants that had fungi in their roots. It is an ancestral symbiosis that is found in all evolutions of life. Fungi were evolutionary geniuses in making these very smart relationships important to plants’ metabolism and chemical balance. A fungus can transform everything, it can destroy and create. They have the capacity to create communication, signals and metabolites, and they have been found to have medicinal properties. Fungi are a high-tech laboratory that can degrade everything to its atomic level and later create what it wants, and we still have no idea how much potential can be found in healthy forests.

What factors or external pressures affect the health of fungi in forests?
In the forest, fungi are interdependent with plants, bacteria, insects, and other animals. In other words, fungi need an ecosystem, substrates, ecological complexity, and vitality. It is difficult to protect a fungus, it is a challenge. For example, in order to take care of a forest specialist like the loyo (Boletus loyo) –which is classified as endangered by the Ministry of the Environment– one needs to try to maintain the functional and structural integrity of the forest. If we want to conserve fungi in the forest, we need to maintain the fallen tree trunks and be careful not to remove or not to step to intensely on the fallen leaves; preserve photosynthetic organisms, plants: trees and the soil, which maintain this layer that ensures for soil not to become dehydrated because of the wind. If we want to protect fungi, we need to protect forests.

How do you continue to raise awareness about fungi?
We need to promote that maintaining a healthy forest also means protecting fungi. For example, a cleared or divided forest is not ideal for fungi. We need to raise awareness of the importance of old-growth forests. The important thing is for there to be global enthusiasm about fungi, people can be inspired by their beauty, colors and textures, truth be told, many artists become obsessed with fungi. After every interaction, there is more affection and development of a transversal interest. It’s also important to generate environmental education activities on fungi with children, because fungi truly are a treasure. They are mysterious and we still don’t know a lot about them, and so they grant us an opportunity to put creativity into action. There’s something abstract in fungi which attracts artists and scientists. But it’s very important to inform oneself about them. It’s as if there is a fever for the harvest, but we must know how to do it, with respect and care. On the other hand, instances like festivals are key, as they can help explain and sensibly introduce the world of fungi.

Chile is the first and only country globally to include the evaluation of adverse effects on fungi in Studies of Environmental Impact on projects or activities. What consequences has this initiative caused and what challenges persist in the conservation and the preservation of the Fungi kingdom in this country, where the Ministry of the Environment has classified 34 species of fungi as threatened?
The Fungi Foundation, with Giuliana Furci at its head, led to Chile being the first and only country in the world where fungi are considered in Studies of Environmental Impact (EIA, its Spanish initials). So, one must consider how flora, fauna, and fungi would be affected by a potential project. This was incredible and there are various countries that wish to replicate this. It’s extremely strategic, because each year more endangered species of fungi are added to the list, as we know little about their relative risks. We are still lacking mycologists that can be dedicated to seeking out new species to classify as endangered–they are then confirmed as endangered by a group of experts, The Classification Committee–because there is a lot we still don’t know, and there is definitely more than 34 species of endangered fungi out there. However, the fact that fungi are now included in the EIA has led to the development of mycology in Chile, not only in academia and in research, but that anyone who is enthusiastic about the diversity of fungi can obtain a well-paying job based around fungi. Therefore, we are seeing many new, excellent mycologists that are learning and sharing information across all of Chile. In this way, fungi are beginning to be classified in varying categories of risk, meaning that it can be significant to find a specific fungus, yet this knowledge has somehow reduced incentives for a certain potential project to occur..

You had the opportunity to conduct research with Professor Suzanne Simard, a forest ecologist, and the author of Finding the Mother Tree, who has conducted experiments to demonstrate how trees can communicate between themselves. How did you come to work with her?
In 2013 I traveled to Canada and I found a YouTube video by Suzanne Simard, in which she suggests that trees can establish mycorrhizal relationships. She posited that these mutualistic connections are not a one-on-one, plant-fungus relationship but that a fungus can continue to grow and connect with another plant or tree, establishing subterranean bridges or bridges of mycelium. That means that there exists the possibility that plants are connected, and this is fantastic. Furthermore, empirical evidence has appeared that suggests that this allows for carbohydrates to travel from plant to plant: and why does this happen, if supposedly plants compete and grow rapidly in the forest because they want more sunlight to perform more photosynthesis and continue to grow, seeking to become stronger constantly? But new evidence suggests that carbohydrates can be transferred to the soil and be spread by the mycelium, reaching another plant. This breaks many scientific paradigms and is the most interesting thing in ecology that I have heard. I was in the same city as Suzanne Simard (Vancouver), I went to her office, knocked on her door, and told her that I loved her work. We ended up becoming friends in time. I started out as an auditor in her classes, and I later did my Master’s research with her.

What else struck you about her work and how did it tie into your research?
What most caught my attention was that in Suzanne Simard’s research, she spoke of the key role of mother trees, paving the way in academia for more scientific articles discussing the mother trees in forests. She was brave, often criticized at first, but today is very renowned.
It was already known, before Suzanne Simard, that there is a transfer of carbon and carbohydrates between plants through mycelium, but she was the first to demonstrate it in a forest and discover a type of pattern; that plants with more shade and less sunlight, meaning that they were not photosynthesizing enough, received more sugar than their neighbors that are able to photosynthesize more.
The mother trees in the forest are important to pass down a legacy and to facilitate regeneration, and so I wanted to write my thesis on this topic. We went to an old-growth forest to study hemlocks, which are trees that tolerate the shade very well, like the mañio tree in Chilean forests. It is a climax species, meaning that it is the last species that appears in a forest, as at the beginning, the first species come, then the next, and finally the species that can tolerate shade the best, which will continue to grow bit by bit, forming an old-growth forest. Hemlock always thrives when growing from decomposing trunks, its seeds germinate in this wood. In this way, my thesis research question was: can these hemlocks on these wooded platforms and in deep shade connect with the forest floor and the roots of their mothers?

What did your research consist of?
What we did was ground-breaking in that we conducted research in the forest and not in a laboratory. We injected glucose–marked at an atomic level to allow us to later detect it–directly to eight mother trees. We took out a piece of bark, reaching the phloem (a type of vascular tissue that can transport carbohydrates and inorganic substances between different parts of a plant) of the tree, where the sap of the tree flows. This took place in the fall because the sap goes more towards the roots, and this is the ideal moment to observe if the regenerating trees were able to receive a little bit of sugar. About 10 to 15 meters away from the mother trees there needed to be a decomposing trunk with many young hemlocks that we could analyze. The study was a success, on day 9 all the small plants had received sugar (carbon-13) from their respective mother tree. The sugar was displaced by nearly a meter daily. In other words, the soil was moving constantly, the nutrients and mycelium were in all forms, transporting nutrients, maintaining signals and pathogen alerts at an impressively dynamic level.

What are the main mysteries that fungi have yet to reveal? And what new challenges or questions have you posed, in terms of your research, dissemination, or other initiatives?
There is still a lot left to understand about how fungi think and make such good decisions, but it’s difficult to understand how this is possible without a brain. How they think, how they remember. For example, a fungus that goes in one direction and quickly finds food in a different one will change its path and grow towards the direction with food, but if it suddenly is unable to go further, it is later capable of remembering where the food was located. There is a great amount of wisdom that is not understood, such as the behavior of hypha (structural units that form mycelium or the body of the fungi). At an ecosystemic level, we don’t know much about its role. They have been new and inspiring in their interconnectivity roles, communication, in decomposition and ability to absorb nutrients for plants. I would like to know more about their role in carbon storage. Many fungi are decomposers. But potentially if we have a mature and healthy forest, there will be many mycorrhizae, especially in temperate forests, and mycorrhizae don’t need to decompose, as they are able to feed off the glucose photosynthesized by plants, so, decomposition activity stops, and here we see the beginning of the accumulation of carbon in the soil. This is all still speculative based on observations I have made. We still do not understand this process well.