Pallets can be reused for stacking firewood off the ground, for example. When recycling, make sure to separate out the treated from untreated wood. Untreated wood pallets that are safe for reuse or clean wood recycling will be marked with these codes: EPAL, HT, and DB. Treated, painted, or colored pallets are marked with one of these codes: MB, EUR and may be landfilled only.