Bay Tree Technologies Nontoxic PureWood decking is made from real wood specially heated at high temperatures and steamed to protect against insects, rot, decay, and water absorption without using chemicals or metals. The process changes the sugars in wood to a substance that insects and mold cannot digest. It can be used in-ground and requires no special equipment or disposal permits. The 5-inch-wide boards come in two styles and seven lengths. 888.575.4180.