One of the six kingdoms of life on Earth, fungi help maintain the equilibrium of ecosystems by connecting the flow of nutrients. Mushrooms consist of mainly two parts: the toadstool—a fleshy, spore-bearing fruiting body typically found above ground—and mycelium—the underground part of a fungus or fungus-like bacterial colony consisting of a mass of branching, thread-like hyphae. The fruiting bodies of mushrooms can be edible or toxic, but all mushrooms are a sign of healthy soil and can be beneficial to the environment by removing pollutants from the earth. Not only can mushrooms capture contaminants, but they can also build carbon in the soil, provide local healthy food sources, recycle debris and waste, and provide a renewable material for artists, researchers, and scientists to fashion into compostable clothing, shoes and building materials.
Our home landscapes benefit from fungi in many ways. When a mushroom is found in the garden, it usually means a plant nearby is dying or has already died and in the process of natural decay, but identifying the mushroom can sometimes help to identify the disease of a tree or shrub. This is the case for Armillaria Root Rot, which can show as clumps of honey-colored mushrooms at the base of infected trees or shrubs—in addition to aboveground symptoms such as branch dieback or leaf yellowing (chlorosis). Beneficial mycorrhizae can be inoculated into soils near these stressed trees, shrubs and even lawns to counterbalance the bad fungi in the soil. Mycorrhizae attach themselves to the roots of the plants and create a symbiotic relationship with the plant. This creates more root surface area where both plant and fungi uptake nutrients together and distribute together. The struggling plant gets more nutrients from the soil thanks to the mycorrhizal fungi and the fungi gets a protected home to survive on. In rain gardens, sheet mulching with wood chips inoculated with mushroom mycelium can be helpful to filter contaminants, absorb water and build carbon in the soil. Of course,discourage pets and children from consuming mushrooms or rake them into the soil or a compost pile if teaching about mushrooms is not an option. If you are seeing fairy rings of mushrooms in your lawn, this usually means there is organic matter such as thatch or a buried stump decomposing under the ground. You can try dethatching your lawn and feeding the lawn in May or September with an organic based, slow-release fertilizer. Mycorrhizal fungi can also be helpful here to help grass roots get the nutrients they need.
Mushrooms help break down organic material such as leaves and twigs, making nutrients in the soil more available for plants, but they can also capture contaminants like E.coli, pesticides, nitrates, phosphorous and mercury. “Mycoremediation” is a process of microfiltration with mushrooms that is employed when restoring disaster struck areas such as oil spills and contaminated water ways. Specific mushrooms found in forests worldwide, like the oyster (Pleurotus ostreatus), can take up E.coli, a fecal coliform bacterium. Furthermore, by placing burlap sacks inoculated with oyster mushroom mycelium strategically near contaminated waterways, scientists can capture and breakdown petroleum-based contaminants, cleaning up that water system and restoring healthy ecology. Turkey tail mushrooms (Trametes versicolor) can bind up mercury and mercuric ions with selenium to form biomolecular bonds that are non-toxic. Basically, they can turn mercury into a safer element! A “mycoboom”, invented by local mycologist Paul Staments, can be used in cases of oil spills in water and is essentially a floating boom of straw inoculated with mushroom mycelium that breaks down oil. Scientifically, the enzymes of the mycelium break down petroleum oils like complex heavy hydrocarbon rings called polycyclic aromatic hydrocarbons or PAHs. Once broken down small enough, bacteria and other smaller microorganisms can finish the decomposition process.
Mushrooms for local healthy food source
Many mushrooms can also be healthy, and sometimes hyper local, food source for humans. They can be a good source of selenium—an antioxidant mineral—as well as copper, niacin, potassium, phosphorous, iron, vitamins C and D, as well as protein. Cell walls in mushrooms are made of the same material as crustacean exoskeletons (called chitin) and they are therefore indigestible unless cooked. Some local mushrooms found in the Pacific Northwest include the apricot jelly mushroom, lobster mushroom, cauliflower mushroom, chanterelle, and black morel. That being said, some mushrooms are toxic and it is important to forage with an experienced mushroom harvester your first few times out. While helpful, guidebooks do not show the array of how mushrooms can appear and sometimes missing a minor detail can be fatal. Prevent mushroom poisoning by making sure you are 100 percent certain of their identification before consuming. A great resource for identification is Puget Sound Mycological Society’s ID Clinic at the Center for Urban Horticulture, Mondays from 4-7p.m. You can also email photos their direction as well.
A new trend in fashion is developing mushrooms into fiber to make textiles for clothing and shoes. Mycelium has a lot of useful properties like insulation, water repellence, microbe-killing and even skin care—all great for use in textiles. Some fashion designers want to make 100 percent biodegradable garments, which would reduce the waste headed to landfills and pesticides needed for conventional cotton farms. Earlier this year, IKEA announced that it is looking to replace its current polystyrene packaging with mycelium-based packaging shaped to fit the forms of objects being shipped.
Though they may seem mysterious and even scary, mushrooms are an important part of the ecology in our backyards and beyond. Get to know the fantastic fungi in your yard to appreciate the complexity of soil health and decomposition in our world! To learn more about local mushrooms and even take free foraging field trips with experts, consider getting involved with the Puget Sound Mycological Society at www.psms.org. If mycoremediation or mushroom science intrigues you, check out Paul Stamets’ work through Fungi Perfecti in Olympia at www.fungi.com. In case of poisoning, please contact a physician or Washington Poison Center: 1-800-222-1222.
For more information on mushrooms in the lawn and garden, please contact the Garden Hotline at (206) 633-0224 or www.gardenhotline.org. You can also find us on Facebook, Twitter, Pinterest and YouTube.