Tom Volk's Fungus of the Month for June. 1997

This month's fungus is Bridgeoporus nobilissimus, the giant polypore of the Pacific Northwest.

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Tom Volk with Bridgeoporus

Bridgeoporus nobilissimus is a polypore fungus with a very large, perennial fruiting body. For a long time this fungus was in the "Guinness Book of World Records" as the largest known fruiting body of a fungus, at over 300 pounds! (that's160 kg for everyone else in the world). It has since become eclipsed by a very large specimen of Rigidoporus ulmarius growing in the Kew Botanical Gardens in England. They're feeding it, though, and I'm not sure whether I consider that "cheating"....

The picture at the left is of me standing next to a large Abies procera with a fruiting body of Bridgeoporus nobilissimus at the base. There are just six known sites in Washington and Oregon at which Bridgeoporus nobilissimus is now known to occur. It should be considered a rare and probably endangered fungus. It is restricted to large specimens of noble fir (Abies procera) and occasionally Pacific silver fir (Abies amabilis) with a diameter at breast height (dbh) of 1-2 meters. Trees of this diameter are not that common. This fungus should be considered endangered because its habitat is endangered. However it is not clear whether the Endangered Species Act applies to a fungus. In this zoocentric world, most people are more interested in the "charismatic mega-fauna" than in some lowly fungus. However the fungi have many important roles to play in the ecosystem and should not be ignored. No ecosystem could exist for very long without fungi! To the right is Sandy Burdsall of Wisconsin showing her appreciation for charismatic mega-fauna.

Rather than write a whole new page on this fungus, I have attached a copy of the paper "Bridgeoporus, a new genus to accommodate Oxyporus nobilissimus (Basidiomycota, Polyporaceae)" from Mycotaxon 60:387-395, 1996, in which we described Bridgeoporus Volk, Burdsall & Ammirati as a new genus, and moved Oxyporus nobilissimus W.B. Cooke to Bridgeoporus nobilissimus (W.B. Cooke) Volk, Burdsall & Ammirati.
Bridgeoporus nobilissimus on a stump

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