Hericium erinaceus
A shaggy, white, pom-pom-shaped mushroom made of cascading spines instead of gills — one of the most recognizable and sought-after mushrooms in cultivation.
Lion's Mane grows as a single rounded mass of long, icicle-like spines that hang downward, giving it a shaggy, white, fur-like appearance that's easy to spot and hard to mistake for anything else. Unlike most mushrooms, it has no cap or stem in the usual sense — the whole fruiting body is one clump of tissue covered in spines.
It belongs to a group called "tooth fungi," named for those spines, which take the place of gills or pores. In the wild, it grows on the wounds of living hardwood trees or on recently dead logs and stumps — beech, oak, and maple are common hosts. It behaves as both a saprotroph, feeding on dead wood, and a weak parasite, colonizing injured living trees through cracks or wounds in the bark.
Unlike gilled mushrooms, Lion's Mane produces spores on the surface of its hanging spines rather than inside gills. A mature fruiting body sheds a fine white dusting of spores that drift on air currents in search of a wound or crack in hardwood.
A spore that lands in a favorable spot — typically the exposed, damaged wood of a hardwood tree — germinates and sends out a hypha, a single fine thread. It needs to meet and fuse with a compatible hypha from another spore before it can grow further.
Once two compatible hyphae fuse, the resulting mycelium spreads through the heartwood, breaking down the wood's structure and absorbing nutrients. This stage can take considerably longer for Lion's Mane than for faster-colonizing species like oysters.
Once the mycelium is well established and conditions shift — cooler temperatures, higher humidity, a burst of fresh air — it forms a single small knot of tissue at the wound site. Unlike clustering species, Lion's Mane typically produces one primordium at a time rather than many.
The primordium swells into the recognizable white, shaggy mass, growing spines as it matures. Good humidity and airflow keep the spines long and the color bright white; the mushroom is usually harvested just before the spines begin to yellow.
As the fruiting body fully matures, its spines release a new generation of spores into the air, and the cycle begins again. Left unharvested, a mature Lion's Mane will visibly develop a fine white spore dust on and beneath it.