Click here to view the original article

From Pippin’s joyful “mushrooms!” exclamation in The Lord of the Rings to the notorious cordyceps fungus that terrorized humans in The Last of Us, fungi continue to capture our imaginations. Considered the third “F” after flora and fauna, fungi are neither plant nor animal and can be found all over the world, sometimes in the most inhospitable places, including salt crusts in the Chilean Andes and contaminated soils in Antarctica. There are an estimated 3–5 million species of fungi, and the largest known organism on Earth may be a fungus. Armillaria ostoyae, found in Oregon, covers approximately 2,200 acres and is estimated to be over 2,000 years old.

All mushrooms are fungi, but not all fungi are mushrooms. Although some can be dangerous and even deadly, most are extremely beneficial and, indeed, essential to life on earth. For humans, the contributions of fungi are myriad. Beyond the obvious culinary and medicinal applications, recent research has experimented with using fungal mycelia in fabrics, construction materials, for bioremediation, and for CO2 capture technologies. But the most important contribution of fungi occurs quietly, underground, and out of sight, contributing to soil health.

The contributions of fungi to soil health are many and varied, depending on the type of fungus. Saprophytic fungi are the decomposers, feeding on dead organic material such as leaves and grass, as well as hard substances like cellulose and lignans contained in wood, returning and retaining nutrients in the earth. Hyphae in mycorrhizal fungi connect to plant roots for a mutually beneficial exchange. The fungi receive sugars from the plant and, in turn, help the plant absorb soil nutrients and water. Some even function as a virtual immune system, protecting their associated plants from pathogens; it is estimated that 90 per cent of plants form a positive relationship with fungi. Another group of fungi is parasitic, which can cause disease but can also help keep other detrimental elements in check.

Given the vast scope of the contributions of fungi to life on earth, it is alarming to learn that 90 per cent of the ecosystems where mycorrhizal fungi dwell are unprotected. According to the International Union for the Conservation of Nature (IUCN), nearly a third of studied fungi are now threatened with extinction. Efforts to increase protections for fungi can’t come soon enough. As David Suzuki notes, “Mushrooms can live without us, but we cannot live without them.”

“No fungi? No forests, no food, no future!”