Adult availability, larval density and penetrability of some important cerambycid beetles associated with Shorea robusta in Midnapore, West Bengal, India.
Cerambycid beetles cause severe damage to the young saplings, weakly standing trees and dead and dying logs of sal (Shorea robusta). The study reported here investigated the adult availability, larval density, larval duration, and depth of penetration of 6 commonly available cerambycid borers, viz. Batocera rufomaculata, Derolus volvulus, Plocaederus obesus, Stromatium barbatum, Xylotrechus smei and Xystrocera globosa on freshly felled sal trees in the dry deciduous tropical forests of Midnapor district, West Bengal in 1986-87. Adult availability and larval density of D. volvulus was the highest in number and that of P. obesus was the lowest. With respect to larval duration and depth of penetration S. barbatum had the greatest values and X. smei the lowest. Data on succession (in terms of months after felling) and distribution of the borers in different areas are also presented. No examples of Hoplocerambyx spinicornis, an important longhorn pest of sal of moist forests, was were found in this area due to its dry atmospheric conditions.