|Major Groups > Polypores > Stemmed, Pale-Fleshed > Grifola frondosa|
Grifola frondosa: The Hen of the Woods
by Michael Kuo
Grifola frondosa, sometimes called the "hen of the woods," is a soft-fleshed polypore recognized by its smoky brown, wavy caps, which are organized in large clusters of rosettes arising from a single, branched stem structure. It is usually found near the bases of oaks, where it causes a butt rot. It is very similar to Meripilus sumstinei (which has larger individual caps, smaller pores, and bruises black) and to Polyporus umbellatus (which has more clearly defined individual caps and stems). Microscopic features will also help separate these species.
Ecology: Weakly parasitic on living hardwoods (especially oaks) and occasionally on conifers; also saprobic on decaying wood; causing a white butt rot; fruiting in large clusters of rosettes near the bases of trees; often reappearing in the same place in subsequent years; summer and fall; widely distributed east of the Rocky Mountains, rare in the west.
Fruiting Body: 15-60 cm broad or more; composed of multiple caps sharing a branched, stemlike structure.
Caps: 2-10 cm across; more or less fan-shaped; gray-brown (often with vague concentric zones); finely velvety or bald; with wavy margins.
Pore Surface: Running down the stem, often nearly to the ground; lavender gray when young, becoming dirty whitish to yellowish; with 2-4 angular pores per mm; tubes to 5 mm deep.
Stem: Branched; whitish; tough; often off-center.
Flesh: Firm; white.
Odor and Taste: Mild; pleasant.
Spore Print: White.
Microscopic Features: Spores 5-7 x 3.5-5 µ; smooth; broadly elliptical; inamyloid. Cystidia absent. Hyphal system dimitic. Clamp connections present on generative hyphae; absent on skeletal hyphae.
REFERENCES: (Dickson, 1785) S. F. Gray, 1821. (Fries, 1821; Saccardo, 1888; Overholts, 1953; Smith, Smith & Weber, 1981; Arora, 1986; Gilbertson & Ryvarden, 1986; Phillips, 1991/2005; Lincoff, 1992; Horn, Kay & Abel, 1993; Roody, 2003; McNeil, 2006; Miller & Miller, 2006; Kuo, 2007; Binion et al., 2008.) Herb. Kuo 10070305.
Further Online Information:
Grifola frondosa at Roger's Mushrooms
Cite this page as:
Kuo, M. (2010, March). Grifola frondosa: The hen of the woods. Retrieved from the MushroomExpert.Com Web site: http://www.mushroomexpert.com/grifola_frondosa.html