What do the mites look like? Wood mites are usually a whitish color. Since they aren't getting on your snake, they very well could be wood mites. Some things that you can try would be to:
1) soak the wood pieces in a diluted bleach/water solution, and then rinse thoroughly and let dry. Make sure that the bleach smell is gone.
2) disinfect the wood pieces with Isopropyl Alcohol. The alcohol will dry fairly quickly, especially if you use a fan or blow dryer. Either way, let it dry until the fumes are gone.
3) place the wood pieces on a cookie sheet and place in the oven on about 150-200F for maybe 20 minutes or so. I've also heard of people placing the wood in boiling water for a few minutes.
The Isopropyl Alcohol is what I use to disinfect my wood pieces when I do cage cleanings. I just put it in a spray bottle and spray them down.