Reishi is native to many areas of the world, including North America.
Identification: These are “shelf mushrooms” (polypores), fungi that grow out of the
sides of living or dead trees. They prefer conifers, especially eastern hemlock. Caps are roughly ear-shaped,
1¾-12" (5-30 cm) across and up to 1¾" (5 cm) thick, woody, lumpy, with a shiny red surface that gradually develops a brownish crust.
The red surface may be fairly uniform, but on some specimens, the color grades from brown at the base, through red, orange, yellow and finally
cream-colored at the edges.
The underside is a white or light brownish color, with fine pores.
Stems are 1-6" (3-14 cm) long, or sometimes not present at all. The fungus produces a brown
Medical: There is evidence that this mushroom contains
substances that inhibit the growth of some cancers, though more research is necessary. It has
long been used in Chinese herbal medicine, for asthma and autoimmune conditions.
Roughly 75 people in North America are poisoned each year by mushrooms, often from eating a poisonous species that resembles an edible species. Though deaths are rare, there is no cure short of a liver transplant for severe poisoning. Don’t eat any mushroom unless you are absolutely certain of its identity! Please don’t trust the identifications on this site. We aren’t mushroom experts and we haven’t focused on safely identifying edible species.
Polyporus tsugae (Murrill)Overh.1915
Ganoderma tsugae description by Thomas H. Kent, last updated 7 Oct 2021.