Healing the Earth With Mushrooms
Picture a mushroom and you probably imagine the familiar cap and stem shape that grows above ground. However, most of a mushroom’s life actually exists underground as a network of stringy tendrils called mycelium.
Mycelia play a vital role in maintaining the balance of life and death in the ecosystem. But these humble fungi may also lead the way toward a healthier, more sustainable future for human civilization as well.
One example comes from 2012, when researchers from Yale University discovered a mycelium strain in the Amazon rainforest that can digest plastic.
This has big potential, because for the past 70 years we have made and thrown away a lot of plastic. In 2013 alone, we produced about 300 million tons of plastic products globally. While a portion can be recycled (about 8 percent), its usefulness only lasts so long, and typical environmental mechanisms can’t break down plastic’s complex chemistry.
Eventually, that old computer keyboard or plastic fork just bulks up another a landfill or joins the millions of tons of discarded plastic floating in our oceans.
This plastic-eating mycelium, Pestalotiopsis microspora, may help us chip away at our accumulation of non-biodegradable waste. Meanwhile, other mycelium strains can help us to break from conventional plastics altogether.
At Ecovative, an environmentally friendly materials company located near Albany, New York, researchers have developed cost-effective, mycelium-based products with significant advantages over their conventional counterparts.
One of Ecovative’s products, Myco Foam, is used by Dell and other companies to replace plastic foam.
Myco Foam is made entirely of fungus and plant material, whereas plastic foam such as Styrofoam is a petroleum-based product made with cancer-causing chemicals. This means that while Myco Foam will be safely absorbed into the soil after it’s served its purpose, plastic foam will remain toxic trash forever.
Some of Ecovative’s products perform even better than conventional ones do. The first product the company developed is a mycelium-based insulation board designed to replace petroleum-based insulation foam. Both products insulate well, but the mushroom option is nonflammable, while the conventional stuff can easily burst into flames.
Ecovative’s mycologist, Sue Van Hook, has been studying fungal ecology for the past 45 years. She says that mushrooms have a lot they can teach us if we listen closely.
“Nature has developed solutions for hundreds of thousands of years. We just have to learn what those solutions are. We know that they’re working solutions because otherwise they would have gone extinct,” Van Hook said. “Fungi have had to adapt to many, many changes in the past 1.7 billion years, so they have this array of genes that are able to respond to different challenges.”
Throughout Earth’s tumultuous history, mushrooms have had to adjust to periods of mass extinction and great upheaval. This has given mycelia a wide variety of features that we can use to our advantage.
“They can bind things together very strongly. They can bind things together loosely. They can bind things together with a lot of elasticity or stiffness depending how we treat other variables. There is a range of properties in the flexible strength and compressive strength that we can extract from their performance based on growing conditions, nutrients, and strains of fungi we choose to work with,” Van Hook said.
An Ecovative product called Myco Board is currently being used in furniture, acoustical tiles, and surfboards, and is soon to be approved as a structural building material. The new, sturdier Myco Board is designed to replace standard particle board, with all the strength but none of the formaldehyde adhesives.
“The fungus acts as a resin to bind plant fibers together. They can either be wood particles, or agricultural products that are more renewable in terms of their life cycles,” Van Hook said.
And unlike plastic resins made from fossil fuels, mycelium is totally sustainable and renewable. “It clones itself as it grows, so it’s a self-assembling resin that just keeps going as long as it has some food,” Van Hook said.
Returning to the Earth
In addition to reducing plastic waste, fungi have many other abilities. Some are used for food. Others are used to make medicine.
Mushrooms also support our lives in big ways that we might not notice. They do Earth’s dirty work. When plants and animals die, fungi help decompose the discarded bodies, completing the circle of life.
“Some fungi work in a symbiotic relationship with plant root systems,” said Van Hook. “For the decomposer fungi, their MO is to take the molecules that the green plants have built through photosynthesis, which take carbon dioxide and water in the presence of sunlight and make sugar. The fungi break down those sugars into carbon dioxide and water. It’s the reverse of photosynthesis.”
In herbal medicine, mushrooms such as reishi, shiitake, chaga, and cordyceps are used to strengthen the human immune system. In his book “Mycelium Running: How Mushrooms Can Help Save the World,” mycologist Paul Stamets says that mycelia help strengthen the immune system of the environment.
“Whether habitats have been damaged by human activity or natural disaster … fungi can aid in recovery. As generations of mycelia cycle through a habitat, soil depth and moisture increase, enhancing the carrying capacity of the environment and the diversity of its members,” Stamets writes.
In order to keep the circle of life turning and the ecological immune system strong, mycelium is an essential component to healthy soil. Just ask Nance (pronounced Nancy) Klehm, a fifth-generation horticulturalist based in Chicago who is currently working on a book about soil.
Klehm’s organization, Social Ecologies, works with local residents to build healthier habitats. One of the techniques Social Ecologies teaches is bioremediation—a practice of using the biological tools of fungi, bacteria, and plants to make healthier soil.
While we usually think of soil quality only in terms of what it can grow, Klehm says it plays many important roles.
“It’s not just about food, but that’s how most people get into this, because they want to grow some tomatoes. A healthy soil supports our air quality. It absorbs our carbon emissions. It absorbs storm water issues and prevents flooding from happening in our basements,” Klehm said. “Soil can do a lot if you work with it. But if we mistreat it, it just becomes dirt.”
Klehm says that mycelia not only preserve moisture in the soil and provide sponginess, they also network nutrients, serve as carbon stores, and absorb contaminants.
“We incorporate mushrooms into a site where we’re trying to support trees, but about 80 percent of plants work with mushrooms in some way,” she said. “We also use mushrooms when there’s a particular inorganic chemical we want to work with. Mushrooms are notorious for cleaning up hydrocarbons and petroleum products.”
The soil revitalizing process can take several years or even decades to complete, but it’s far less expensive and much more holistic than the conventional method.
Klehm says that when the U.S. Environmental Protection Agency (EPA) cleans up a site, it removes and trucks the contaminated soil to a landfill, or chemically cleans or burns it. Then it typically installs a permeable barrier, adds several feet of limestone, and then tops the site with fresh topsoil.
Klehm says the EPA is genuinely interested in her soil restoration methods, but the nature of bureaucracy makes the EPA slow to embrace them. On a community-wide scale, however, bioremediation projects are taking place all over the world.
“First Nation people are working on this really hard,” Klehm said. “For people whose cultures are critically tied to the land, their culture falls apart if their land isn’t healthy. In an urban area, we don’t realize that we’re tied to land so we ignore it and mistreat it.”
Mushrooms are essential to life on Earth in many ways. The better we can understand and utilize their power, the brighter our future.
“There’s a phobia against fungi, and that’s why I think it’s been so in the closet for so long,” said Van Hook. “This is about overcoming fear, and trusting that nature has always taken care of us and will continue to take care of us.”