Abstract

Cossus cadambae Moore (Lepidoptera, Cossidae) is a relatively new insect pest of teak in India and it has recently assumed major pest status in several plantations in Kerala, Tamil Nadu and Karnataka States. Caterpillars of this insect characteristically bore in to the wood of standing trees leading to deterioration of timber. C. cadambae has annual generations with an exceptionally prolonged larval stage. At Palappilly, Kerala, where the study was carried out, the generations were continuous and overlapping. The progression of infestation intensity among the trees was studied here. The intensity of attack was studied by scoring the affected trees visually into the following score classes viz., 0 = healthy tree1 = low level infestation with a few scattered borer holes2 = medium level of infestation with borer holes confined to small groups3 = heavy infestation with numerous borer holes in large patches all over the stem and 4 = tree dead as a result of heavy