Natural Durability of Imported Timber in Indian Climatic Condition

Abstract

Evaluation of natural durability in specific climatic conditions is a must before putting timber to use for specific purposes. In the present study, 22 different timber species, imported from different parts of the world were assessed under durability trials by stake tests in the test field of Dehradun, India (Latitude: 30°19’ N and Longitude 78°04’ E). The species were chosen keeping in mind the increasing trend of wood import in the country for the last few years and their possible commercial applications, in situ uses and importance in future. Inspections were carried out quarterly for the first year, half-yearly for the second and third years and yearly for the subsequent years. Visual inspection and knife tests, whenever required, were performed to evaluate and analyse the extent of decay and numerical ratings in line of the same were assigned. Stake test data after 3 years’ trial indicated that all 22 species of imported origin were non-durable (ND) under the climatic condition of Dehradun, India. Quite predictably, extent and severity of decay varied a lot amongst different species which supports the authors hypothesis of using specific timber for specific climatic zones and purposes. Evaluation and performance of imported timber with or without preservative is must before recommendation for in service conditions. The test results highlight the need of establishing an Indian Standard specification in terms of quality and performance of such imported timbers of ND and plantation origin so as to guide the budding timber industries of the country in terms of judicious selection of species to ensure efficient use in service.