Submitted to: Journal of Economic Entomology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 12/26/2000
Publication Date: 4/20/2001
Citation: Morales Ramos, J.A., Rojas, M.G. 2003. Nutritional ecology of the formosan subterranean termite (isoptera: rhinotermitidae): i. feeding preference and deterrence. Journal of Economic Entomology.
Interpretive Summary: Since its introduction to the United States during the 1960's, the Formosan subterranean termite, Coptotermes formosanus, has been one of the most destructive termites in the continental U.S. It is estimated that the Formosan termite cause damage of several millions of dollars annually to houses, other buildings, utility poles, railway sleepers, boats and ships, paper, and living trees. However, termites do not eat wood indiscriminately and they are known to exhibit feeding preferences. The objectives of this study were to determine which species of wood (commercially available in New Orleans) were the most preferred and which the least preferred by the Formosan termites. Preferred woods can be useful to improve detection and monitoring of termite activity. In this study 5 woods including birch, red gum, sugar maple, pecan, and red oak were more preferred than southern yellow pine (SYP) wood. The use of any of these 5 woods species within underground monitoring stations may improve the speed of detection of termite activity by competing more effectively as food sources with houses and other structures built with SYP wood. No-preferred wood species can be useful to build structures with some degree of termite resistance. In this study, Alaskan yellow cedar, Western red cedar, sassafras, Eastern red cedar, and 4 exotic wood species were rejected by the Formosan termite as food sources. The use of any of these woods may delay termite infestation of wooden structures.
Technical Abstract: The feeding preferences of the Formosan subterranean termite (FST), Coptotermes formosanus Shiraki (Isoptera: Rhinotermitidae), were tested in 3 separate experiments on 28 different wood species. Experiment 1 was a multiple-choice test designed to test relative preferences among 24 wood species commercially available in New Orleans, LA. Experiment 2 was a similar study designed to test relative preferences among 21 wood species shown or reported to be unpalatable to the FST. Experiment 3 was a non-choice test to probe the feeding deterrence of the 10 least preferred wood species. Preference was determined by consumption rates. Birch, red gum, Parana pine, sugar maple, pecan, and red oak were the most preferred species by C. formosanus in order of consumption rate. All these species were significantly more preferred than Southern yellow pine, widely used for monitoring. Sinker cypress (equals old growth bald cypress), Western red cedar, Alaskan yellow cedar, Eastern red cedar, sassafras, Spanish cedar, mahogany, Indian rosewood, Honduras rosewood, and morado induced significant feeding deterrence and mortality to C. formosanus. The last 8 species produced 100% mortality after 3 months.