Notes: A medium to large kidney shaped shelf with a short stout stalk at the periphery. The cap is brown to whitish with a very thin skin that often peels off, revealing white flesh. The edge is rolled down and covers the peripery beneath. The underside is white with closely spaced roundish pores. The more mature cap underside is covered with long, very slim brown tipped “teeth” I’m calling this Piptoporus betulinus but don’t know whether these “teeth” or “spikes” go along with this ID.