a survey of beetles damaging commercially impotrtant ... - Icrisat.ac.in

I. INTRODUCTIONAbout 100 commercially useful softwood and hardwood timber speciesare extracted from the natural forests of Kerala.raised in plantations.Some of these are alsoThe felled timber is usually stored in the open forvarying periods before transportation to the site of utilisation.In factoriesalso, timber made available in different seasons may be stored for use at alater stage.During such periods of storage, the timber is attacked by variousbeetles which tunnel into the wood and convert it into wasteful powder.These insects may gain entry into the wood from the area where it was firststacked after cutting or while stored as raw or converted timber.At present, the State is facing acute shortage in the supply of rawtimber, especially the softwoods. Recently, about 41 timber species widelyused in various industries have been brought under the provisions of theEssential Commodities Act (1961), according to which the transit of any o fthese timber species to outside Kerala, other than as finished products, hasbeen restricted. It is obvious that we must take adequate measures toprevent the wastage of the scarce raw materials available. Knowledge ofthe identities of the borers and their nature of attack are essential for evolvingsuitable management procedures to prevent insect-caused deterioration oftim ber.Pioneering work on the coleopterous borers of Indian timbers wasdone by Stebbing, during the turn of this centurv (Stebbing, 1914).gave a detailed account of the morphology, taxonomy, biology and bionomicsof various species attacking important timbers.HeIt was shown that theimportant borers belong to the families, Cerambycidae. Bostrychidae, Lyctidae,Platypodidae, Scolytidae, Curculionidae and Anthribidae.Much of the earlier work was of a taxonomic nature involving thesurvey, collection, identification and description of species encountered onvarious timbers.The biology of some important borers were also workedout. These studies were summarised by Beeson (1941) in his classic workon the ecology and control of the forest insects of the Indian sub-region.