The idea of baking it sounds like a good course of action. I recently got some eco earth from a reptile expo and did have some trouble with wood mites, although I can't be sure it was the bedding. I do have a large wood branch in the tank as well and there were two half log hides at the time. I wound up switching out the wood hides for ceramic, baked the branch and replaced the substrate and haven't had any issues since. Correct me if I am wrong, but haven't some mite treatments been linked to neurological issues in snakes after even a single use? I would be really scared to use any chemical in the tank as a part of regular maintenance, but I may be remembering a different brand. Just something to consider maybe. I have also read that the mites are usually dormant in the bedding and that quite a bit of wood anything will have them, but that it takes certain conditions for them to hatch and spread. If I remember correctly the main condition for their development is high moisture. This seems to make sense given that they showed up immediately following a shed cycle and the bedding had been consistently damp for about a week and a half. I suspect that the bedding wasn't the issue for me however, since I am still using it and haven't had any further problems.