Birch Polypore Fungus

Birch polypore fungus, Piptoporus betulinus, growing on a decaying birch log (Betula sp).  This fungus is common wherever there are decaying birch trees.

I collected the following small specimen:

The underside was covered with pores, about 3 per mm:

The specimen only gave off a few small spores.  These are shown in the following image (x600, image width about 86um).

These spores are about 4 x 1.5 um in size, which agrees well with the 3-6 x 1.5-2um given at MushroomExpert.com.

First photo taken and specimen collected in the Wilderness, Whiteknights Park, Reading, UK, on 2012-12-15.