Comparative study of the resistance of six bamboo species to attack by Coptotermes formosanus Shiraki and Coptotermes gestroi Wasmann (Blattodea: Rhinotermitidae)

Bamboo is widely grown and utilized as a construction material around the world, particularly in the tropics. At present, there are about 70 bamboo species and varieties recorded from Hawaii. The objective of our study was to determine the relative resistance of six Hawaii-grown bamboo species to attack by Coptotermes formosanus Shiraki (Formosan subterranean termite) and Coptotermes gestroi Wasmann (Asian subterranean termite). Four-week laboratory feeding trials were performed as described in standard E1-09 of the American Wood Protection Association (AWPA 2009). Samples of each of the six bamboo species were individually exposed to 200 termites (with 10% soldiers); and termite mortality, wood mass loss, and visual appearance of the samples (on a scale of 0-10) were recorded at the conclusion of the trail. Mean mass losses of the six species as a result of termite feeding ranged from 14-29%; with the two most resistant bamboo species, Gigantochola pseudoarundinacea and Bambusa oldhamii, demonstrating significantly greater resistance to termite attack than the most susceptible bamboo species, Guadua anguistifolia, with both termite species. Dendrocalamus brandisii, Dendrocalamus latiflorus, and Bambusa hirose were intermediate in their termite resistance. Overall, we observed very little difference in wood preference between C. formosanus and C. gestroi. Although bamboo is a very promising construction material, and species clearly differ in their susceptibility to termite attack, all six species evaluated in the present study would require additional protection for use under conditions of high termite pressure.