Penetration depth evaluation approach for termite-infested Shorea spp. lumber

The pattern of termite infestation was investigated in structural lumber, light Red Meranti (Shorea spp.), using a minimally destructive technique. The relationship between the visual inspection and the pin penetration approach in predicting the basic properties of wood was determined, and a pin penetration distribution value was mapped into a contour map based on the Kriging interpolation technique. Small wood block samples were exposed to reared subterranean termites Coptotermes curvignathus Holmgren (Isoptera: Rhinotermitidae). The characteristics of termite infestation and the changes in the physical-mechanical properties were investigated. The residual surface area of the samples was evaluated using Pilodyn®. The characteristics of the termite galleries found on small wood block samples were as follows: 1) the termite galleries varied in length, or 2) the galleries consisted of long flat tunnels in a longitudinal direction, clean, not decayed, and contained no soil residue. The weight loss percentage from this study exhibited a similar trend with the pin penetration depth, which was directly proportional to the exposure period. The pin penetration result from Pilodyn® generated distribution map that was represented the conditions and basic mechanical properties of the samples. Pilodyn® can be used a complement for visual inspection in in-situ assessment.