1. Is mold/mildew growing on your logs? First determine whether it is on top of the stain or underneath by dabbing it with a swab soaked in chlorine bleach. If it is on top of your finish, it can be washed off the walls using Log Wash. If it is underneath, you must remover the finish in order to remove the fungal stain. 2. Decay-causing fungi occur in wood with moisture contents in excess of 30 percent (the wood-fiber saturation point). Since moisture must be present to give fungi a chance to grow, a good, water-repelling, breathable finish applied to the surface of the logs will combat this. 3. If rot does take root in your logs, drill holes into the affected log, inject Shell-guard on each side of the problem area and then caulk the holes. The borate dissolves and begins to diffuse throughout the wood, killing the fungi on contact. This content was provided by Perma-Chink Systems, Inc.