After a forest fire, it doesn’t take long for bonfire scalycap (Pholiota highlandensis), a humble but prolific brown mushroom, to emerge from the blackened earth. But in between blazes, it disappears—to no one knows where, sometimes for decades. Now, research suggests the scalycap and several other species of fire-loving fungi spend the years between fires hiding out in the tissues of neighboring lichens and mosses.
For years, scientists have tossed around the idea that fire-loving fungi remain undetected for years by hiding inside other organisms, emerging only when their cocoon burns up around them.
To see whether this “bodysnatcher” hypothesis was correct, researchers collected mosses, lichens (above), and soil samples from burned and unburned areas in and near Great Smoky Mountains National Park months after a forest fire. The team disinfected the surfaces of their samples and analyzed the DNA inside.
Remarkably, the team found genetic signatures from 19 species of fire-loving fungi within the mosses and lichens themselves, they report online this week in Fungal Ecology. That suggests the fungi might use these materials as a kind of insulating shelter, waiting there until the next inferno. The team also found the DNA of three fire-loving fungi species in the soil, even in unburned areas. So there might be multiple ways the fungi are biding their time, the researchers say, including as fire-resistant spores underground.
Although it’s not yet known how these forbearing fungi manage to inhabit other organisms for so long, it’s clear that their adaptations shed light on scientists’ understanding of how ecosystems recover from wildfires.