|Description||Grifola frondosa is a polypore mushroom that grows in clusters at the base of trees, particularly oaks. The mushroom is commonly known among English speakers as hen-of-the-woods, ram's head and sheep's head. In the United States' supplement market, as well as in Asian grocery stores, the mushroom is known by its Japanese name maitake, which means "dancing mushroom". Throughout Italian American communities in the northeastern United States, it is commonly known as the signorina mushroom. G. frondosa should not be confused with Laetiporus sulphureus, another edible bracket fungus that is commonly called chicken of the woods or "sulphur shelf". The fungus becomes inedible like all polypores when they are older, because it is too tough to eat.
G. frondosa grows from an underground tuber-like structure known as a sclerotium, about the size of a potato. The fruiting body, occurring as large as 100 cm, is a cluster consisting of multiple grayish-brown caps which are often curled or spoon-shaped, with wavy margins and 2?7 cm broad. The undersurface of each cap bears approximately one to three pores per millimeter, with the tubes rarely deeper than 3 mm. The milky-white stipe (stalk) has a branchy structure and becomes tough as the mushroom matures.
In Japan, the Maitake can grow to more than 50 pounds (20 kilograms), earning this giant mushroom the title "King of Mushrooms". Maitake is one of the major culinary mushrooms used in Japan, the others being shiitake, shimeji and enoki. They are used in a wide variety of dishes, often being a key ingredient in nabemono or cooked in foil with butter.|