Confidence: It might be this.
Notes: A stalked polypore sp found growing on a cut deciduous log. Most of the nearby trees were Beech or Sycamore, so presumably either of those. The cap was pale (the green streak came from a blade of grass stuck to the top). I was looking for Winter Polypore, but I am assuming that the dark band at the bottom of the stipe means that this is Blackfoot Polypore.