Wood continues to be one of the most widely used raw materials in spite of the introduction of many modern materials. This naturally renewable resource being an organic matter is amenable to the attack of biodeteriorating organisms. Though some wood species are known for their natural resistance to agents of biodeterioration, their availability is constantly decreasing, besides being too expensive. The increasing demand for timber instigates the humans to utilize timbers lacking natural durability. This is made possible only through treatment of perishable woods with wood preservatives and insecticides. In this paper we reviewed the insecticides being used to protect woods in the Indian condition. Further studies were undertaken to evaluate the efficacy of rubber wood stakes impregnated by pressure (15 minutes vacuum followed by 50 lbs./sq.inch air pressure for 30 minutes) with a organophosphorus insecticide, chlorpyriphos @ 1% & 2% a.i. and three synthetic pyrethroid insecticides viz., fenvalerate 1% & 2% a.i., cypermethrin @ 0.5% a.i and alphacypermethrin @ 0.5% a.i. against subterranean termites. The data collected indicated that within 6 months of implantation there was damage of 61.4 % in untreated stakes, which was total within 12 months of implantation. Among the insecticides chlorpyriphos and fenvalerate treated stakes were free from any damage at both the evaluated concentrations for more five years while stakes treated with, cypermethrin and alphacypermethrin recorded 84% and 80% damage at 5 years after exposure. These findings demonstrated that the insecticides like chlorpyriphos and fenvalerate could be effectively used for preservation of highly perishable woods.

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