I have an 11 week old Golden Retriever. I have a good size backyard. Unfortunately have a large tree that's coming down soon due to disease and dead branches, but the large area around it was a mud pit for a few years. So I put in many bags of pine bark I think it was, and now my puppy likes to chew on them, and possibly is eating some too. Do you think this is bad for him? He eats well, is growing well, poops are normal, seems to be doing just fine. Thank you!