Grifola umbellata

Taxonomy

Phylum: Basidiomycota

Class: Agaricomycetes

Order: Polyporales

Much less common than the related species Grifola frondosa, known as Hen of the Woods, the fruitbodies of Grifola umbellata are fairlyshort-lived; they occur at the bases of deciduous hardwood trees, and most often on oaks. This fungus attacks living trees and causes a white rot. (Pictures: Hugh Purvis)

Although this is an edible polypore this polypore is so rare that it should not be collected for eating.

Identification Guide

	Description The whole fruitbody can be up to 50cm in diameter; it comprises a thick fleshy basal stem that branches repeatedly with terminal branches ending in shallowly-funnelled caps with thin, wavy margins. Caps The individual caps are initially greyish brown covered in fine fibrils or small fibrous scales. The caps, which have white flesh when young, turn ochre and then brown as they age.
	Tubes and Pores The fertile undersurface of the cap comprises shallow tubes typically 1 to 1.5mm deep and usually rounded; they terminate in pale cream angular pores spaced at typically 1 per mm and decurrent to the stem.
Spore print	White or creamy yellow.
Odour/taste	Pleasant sweet odour when young; less so when decaying. The taste is initially sweet, ultimately becoming rather acrid.
Habitat	At the bases of oak trees and other hardwoods.
Season	Summer and autumn.
Occurrence	Very rare.
Similar species	Grifola frondosa, Hen of the Woods, is more common; its fruitbody has terminal branches that end in fan-shaped or leaf-like fronds rather than rounded umbels. Could possibly also be confused with the much paler Wood Cauliflower, Sparasis crispa, but that grows only at the bases of conifers and most frequently Scots Pines.

Reference Sources

Fascinated by Fungi, Pat O'Reilly 2011

Dictionary of the Fungi; Paul M. Kirk, Paul F. Cannon, David W. Minter and J. A. Stalpers; CABI, 2008

Taxonomic history and synonym information on these pages is drawn from many sources but in particular from the British Mycological Society's GB Checklist of Fungi and (for basidiomycetes) on Kew's Checklist of the British & Irish Basidiomycota.