WHY PILE WRAP? Prevent Marine Borers: Destructive Organisms Marine borers are found in most saltwater and brackish environments. In fact, as toxic pollutants in coastal areas and estuaries diminish, the marine borer problem is becoming more severe. There are two major types, or subfamilies, of marine borers: Mollusca and Crustacea. The Mollusca have seven genera with the most common being the Teredo, or shipworm. Other common genera include bankia and pholads. Mollusca bore into the interior of exposed wood structures and construct elaborate networks of non-connecting tunnels. In the process, the structural integrity of the timber is destroyed. The Crustacea subfamily has three genera: Limnoria, Chelura, and Sphaeroma. All three groups will attack the exterior of submerged marine structures. In heavy concentrations, these organisms will completely girdle piers and piles at the waterline, producing a typical ÒhourglassÓ configuration and eventually, structural failure. As with fungi, the best way to prevent attacks by both types of marine borers is to remove the food supply through pressure treating with Wolmann CCA preservative.