I'm new to wood burning and I am not sure what I can burn on. I would like to burn on old birch bark that I collected while hiking as well as old ash that was salvaged when a dead tree fell on our property. My question is can I safely burn on these types of "found" woods. Can I collect various branches and barks and burn on them? I have no idea what I'm doing but this is the direction I want to go. Any advice is helpful thanks you!