CatzOr, if your mount is small enough I would recommend microwaving the piece of wood (before you put the orchid on of course) this should take a fungi that may want to start growing later, especially if it is going to be moist for periods at a time. I try to mount most of my orchids, they seem to like it better. I have an Aerangis modesta that is mounted its growing great but I have trouble keeping it moist throughout the day, so make sure you add something that retains some moisture. I use spaghum then I add sheet moss over top works pretty good. Best of luck to you, hope it works!