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
Pine tar weather. Pine tar has long been used in Scandinavian nations as a preservative for wood which may be exposed to harsh conditions, including outdoor furniture and ship decking and rigging. The high-grade pine tar used in this application is often called Stockholm Tar since, for many years, a single company held a royal monopoly on its export out of Stockholm, Sweden. It is also known as "Archangel Tar". Tar and pitch for maritime use was in such demand that it became an important export for the American colonies, which had extensive pine forests. North Carolinians became known as "Tar Heels."