Nootkatone, one of over 300 components of vetiver oil, is a mildly pungent sesquiterpene ketone with a distinctive grapefruit flavor, largely responsible for vetiver oil unique aroma. As part of our research on natural products efficacy against Formosan subterranean termite, the major wood pest in the USA, previous experiments showed that vetiver oil and nootkatone disrupt normal termite behavior and significantly affect feedingability and survival. A novel bioassay for the evaluation of nootkatonetreated wood and sand was designed to better understand how nootkatone affects the behavior and physiology of these termites. Daily counts on the number of feeding termites, weekly measurements of food consumption, abundance of symbiont protozoa present over time and termite survival were recorded. Our study proved that this essential oil component acts as a repellent, as a feeding deterrent and as a toxicant to Formosan subterranean termite. Nootkatone represents a promising natural alternative to synthetic termiticides for the management of termite control.