It grows on almost every locust tree in the woods here. I usually shave off a few thin slices and put them in the middle of the tinder bundle. Put the coal on the slices and get them started. When the polypore gets to glowing, fold the bundle up around it and blow it into flame. Really helps with damp or not-so-good tinder. they usually work right off the tree unless it's been really wet weather-the pores are on the underside and don't usually get too wet.