Genus PolyporusGENUS POLYPORUS
The genus Polyporus and the genus Trametes have the pores closely packed and united to together. In Trametes the uniting substance is the same as the substance of the cap, but in Polyporus the uniting substance is different from the substance of the cap. The genus Polyporus in its widest sense is a large, one, numbering some five hundred species, and containing every texture from fleshy or pulpy to woody.
The fruiting portion is often seen in the form of brackets shelving out from standing or fallen trees. The mycelium penetrates the wood, softening it, and causing it to crumble, so that in the course of time the tree dies. The external evidence that the tree has been attacked is the appearance of the fruiting portion, which often attains a very great size.