Grifola frondosa is a species of edible mushroom in the family Meripilaceae, commonly known as maitake or “hen-of-the-woods.” It is native to temperate forests of East Asia, Europe, and North America, where it grows at the base of hardwood trees, particularly oaks. The genus name Grifola is derived from Greek gryphos, a mythical griffin, possibly referring to the clustered, elaborate form of the fruiting body, while the species epithet frondosa comes from Latin meaning “leafy” or “full of leaves,” describing its many overlapping, frond-like caps. The Japanese name maitake (舞茸) translates to “dancing mushroom,” reflecting folklore that foragers would dance with joy upon finding it due to its culinary and medicinal value.

The mushroom forms large, multi-branched clusters composed of numerous gray-brown, fan-shaped caps arising from a single base. It grows as both a saprotroph and weak parasite on hardwood trees, contributing to wood decomposition and forest nutrient cycling. Historically, Grifola frondosa was highly prized in Japan and China, where it was collected from the wild before the development of modern cultivation techniques. Today it is widely cultivated and available commercially in fresh and dried forms.

Grifola frondosa is valued for its rich umami flavor and firm, slightly fibrous texture. It is used in a variety of culinary preparations including stir-fries, soups, hot pots, tempura, and grilled dishes. The mushroom readily absorbs flavors from broths and sauces while contributing its own savory depth, making it a popular ingredient in both traditional and modern cuisine.

Nutritionally and chemically, Grifola frondosa contains a range of bioactive compounds. It is a source of dietary fiber, protein, B vitamins, and minerals such as potassium and copper. Notably, it contains β-glucans, a class of polysaccharides that have been studied for immunomodulatory effects, including potential stimulation of innate immune responses in experimental systems. Other compounds include ergothioneine, phenolic antioxidants, and small amounts of sterols such as ergosterol, which can be converted to vitamin D₂ upon exposure to ultraviolet light.