Wood preservation a long-practised method and often used in today's carpentry workshops. Technological developments mean it is also possible to spray preservative over the surface of the timber. Some of the liquid is drawn into the wood as the result of capillary action before the spray runs off or evaporates, but unless puddling occurs penetration is limited and may not be suitable for long-term weathering. By using the spray method, coal-tar creosote, oil-borne solutions and water-borne salts (to some extent) can also be applied. A thorough brush or spray treatment with coal-tar creosote can add 1 to 3 years to the lifespan
Birch tar is an effective repellent of gastropods. The repellent effect lasts about two weeks. The repellent effect of birch tar oil mixed with petroleum jelly applied to a fence lasts up to several months. Birch tar oil is also used in perfumery as a base note to impart leather, tar, smoky, and wintergreen notes. Birch tar Birch tar or birch pitch is a substance (liquid when heated) derived from the dry distillation of the bark of the birch tree. It is composed of phenols such as guaiacol, cresol, xylenol and creosol. Birch tar was used widely as an adhesive as early