Turkey Tail grows on dead wood in forests almost everywhere, so a lot of people have met it. In China it is yunzhi, the cloud mushroom, a name often put down to its wavy, many-colored cap, and Chinese medicine has used it for at least two thousand years. In Japan it is kawaratake, the mushroom by the river. Native peoples in many places made necklaces and ornaments from it.
In China it was brewed as a tea, recorded as far back as the Ming dynasty, in the 1400s. Traditional Chinese medicine used it to strengthen the body and increase energy.
The old Taoists saw it growing at the foot of evergreen pines and believed it gathered yang from the tree, the bright side of things tied to vitality and strength, and passed it on to whoever took it. To them it was a mushroom of endurance. That's tradition, and much of it is legend, and we call it that. What brings people to it now is different. Immune support is why it goes into the morning drink today.