Grifola frondosa

Scientific name:   Grifola frondosa (Dicks.: Fr.) S.F. Gray
Derivation of name:   Grifola is from an Italian fungus name;
frondosa means full of leaves (i.e., many caps).
Synonymy:   Polyporus frondosus Dicks.: Fr.
Common names:   Hen of the woods.
Phylum:   Basidiomycota
Order:   Polyporales
Family:   Meripilaceae
Occurrence on wood substrate:  Parasitic; in dense clusters
of overlapping caps on the ground at the base of deciduous
trees and stumps, especially oak and maple; September
through November. 
Dimensions:  Rosette-like clusters can be as large as 60 cm
across. Individual caps are 2-7 cm wide and attached to a
branching stalk which can be 2-4.5 cm long and up to 10 cm
thick.  
Upper surface:  Gray to brownish-gray or dark brown;
somewhat zonate; smooth or finely roughened
Pore surface: White to yellowish; pores 1-3 per mm.
Edibility: Edible, considered choice.
Comments:  This weak parasite of tree roots can be found at
the same site year after year. It is a highly sought after edible
species.

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Figure 1. This good-sized specimen of Grifola frondosa made
for a delightful find during a foray.

Figure 2. Several clusters at the base of a tree. Photo ©
Pam Kaminski.


Figure 3. Hen of the woods. Photo © David Work.

Figure 4. The white pore surface contrasts sharply with the
brownish caps. Photo © Pam Kaminski.

Figure 5. White pore surface of Grifola frondosa. The
individual pores are easy to see at 1-3 per mm.