Wood being a biological materials readily degraded by Bacteria, Fungi, Termite & Borers .However ,some wood species are resistance to these degrading agents while others are very susceptible to deterioration. Those that are susceptible must be treated with preservative chemicals to increase their service life. Wood Preservation is a process of reducing and/or preventing attack by wood deteriorating agents thereby increasing the service life of wood .The resistance is mainly due to the accumulation of extractives in the heartwood some of which are Decay inhibiters. Sapwood lacks these deposits completely rendering it susceptible to attack by Fungi /Termites & Borers. Presently we are using plenty of plantations Timber which is of merely 4-5 yrs of Cultivation and they have no scope of Heartwood growth in them. So, all species must be treated. The chemical composition and amount of extractives in wood is highly variable within and between tree species and range from 2-15 % of wood weight. Naturally Durable timber accounts to as much as only 10 % of wood used in industrial sector in India (IWST –report says).Wood Treatment are just 5% of the total wood supply.