I had a tree fall in my back yard several years ago and I kept the bark after cutting it up for firewood. I'm wondering if the bark is OK to mount orchids on. I've got 4 large garbage pails full of bark that I've kept dry in the garage for the past several years. I just don't want any problems i.e. some bacterial growth, virus, disease that may be on the bark to infect my orchids. Anyone have any advice?