Birch Polypore Piptoporus betulinus
Cap Apolypore is grey-brown at first and almost spherical, flattening and turning browner on top and white underneath as during maturation .10 to 25cm in diameter and 2 to 6cm thick when mature, fruiting bodies arise singly but can often be many on theone host tree looking like a cascade of steps
Tubes and PoresThe small white tubes are packed together at a density of 3 or 4 per mm; they are between 1.5 and 5mm deep and terminate in white pores that turn buff as they age.
SporesCylindrical to ellipsoidal, smooth; 4-6 x 1.3-2µm.
Spore print White.
Odour/ Taste Bitter tasting, when cut these polypores have a faint but not unpleasant 'mushroomy' odour.
Habitat It is by and large restricted to dead or dying birch trees. Brackets are annual but may persist thyrough one winter.The species is parasitic on living trees, but it can also live as a saprobe once the tree has died and so is able to fruit in subsequent years until the trunk rots away.