Here are images I have of many polypores and crusts we studied as part of COMA's Mushroom University 2011 workshop with Gary Lincoff. We see all of these usually summer through winter on our walks and forays. They are listed in alphabetical order. I will gradually be adding comments for each photo. If you are looking for reccomended sources for studying polypores, consider consulting the following: North American Polypores by R.L. Gilbertson and L. Ryvarden; POLYPORACEAE by Annarosa Bernicchia; The POLYPORACEAE of the United States, Alaska and Canada by L.O. Overholts; and Vol. 2 of The Fungi of Switzerland.
Dianna