The Invisible Force Keeping Carbon in the Ground
The giant chestnut tree, growing in place for hundreds of years, would have been impossible to miss. Its leaves were glossy and dark green, its bark riven like a mountain range seen from above. The fungi it relies on were harder to see.
A fungi-hunter is not looking for an object so much as a system, brushing aside a layer of damp leaves to find the gossamer filaments that hold up the world. These multitudes of hairlike fungal threads—individually called hyphae, and collectively, mycelium—are the true body of fungi, shuttling nutrients to and fro across the forest floor. The blackness of soil is also a tell: A layer of loamy, shiitake-smelling richness, two or three inches deep, is a sign that fungi are making more life out of old life, digesting the dead to feed back into the system, keeping the whole scene alive.
Fungi-hunting is what I found Toby Kiers and her team of mycologists doing one morning, when I reached them via video call in Corsica, the French island in