Q&A With the Sentricon Field Scientists

Dr. Michelle Smith, Dr. Joe Demark, Dr. Joe Eager and Dr. Barb Nead-Nylander

Q: How large is an average size Eastern subterranean termite colony and how can you determine its size?
A: Experts differ on this question, because subterranean termite colony sizes vary by factors that include species, location and the age of the colony. As a rule of thumb, a desert subterranean termite colony (Heterotermes aureus) might number 80,000; an Eastern subterranean colony (Reticulitermes flavipes) might number 250,000; and a Formosan subterranean colony (Coptotermes formosanus) might number 1 million.

Research for the Sentricon^® System, dating back more than 15 years, has focused on the amount of bait required to eliminate a typical colony. For example, the Eastern subterranean termite is the most common species in the United States. Research has shown that 65 grams of Recruit^® IV termite bait is sufficient to eliminate a typical Eastern subterranean termite colony. One Recruit HD termite bait device contains 150 grams of bait and is, therefore, sufficient to eliminate more than two Eastern subterranean termite colonies. The important point for a homeowner to know is that Sentricon provides proven termite colony elimination and ongoing preventive protection when installed and maintained according to the label.

Q: How long does a queen termite typically live? Does Recruit^® termite bait affect them?
A: While it depends heavily on the termite species and location, a queen termite can live a decade or longer, according to the Mallis Handbook of Pest Control. Queens have the longest life span when compared with workers and soldiers. However, a study* conducted on Coptotermes termites in Australia showed that when queens are exposed to Recruit termite bait, egg production declines first and queens can die within the first month. Eggs also stop developing and no longer hatch. Molting of the young larval stages, workers and nymphs are all affected, leading to colony elimination.

*Lenz M, P.V. Gleason, L.R. Miller and H.M., Abbey. 1996. How predictive are laboratory experiments for assessing the effects of chitin synthesis inhibitors (CSI) on field colonies for termites? – A comparison of laboratory and field data from Australian mound-building species of termite. International Research Group on Wood Preservation. 27th Annual Meeting 1-10.

Q: How often can multiple termite colonies hit a home?
A: It is common for sites to be hit by multiple termite colonies, especially in the South and in the West. In a Termiticide Scientific Review Panel (TSRP) study conducted by Dow AgroSciences from 2007 to 2011, 112 sites installed with Recruit HD termite bait across the United States were inspected for multiple termite colony activity by using DNA analysis. Sentricon stations were inspected at each site and termites (R. flavipes, C. formosanus, H. aureus and R. hesperus) were collected from each station. An average of four termite colonies was found at each site. Here are some of the results:

• 37 percent of the sites had one colony
• 25 percent of the sites had two colonies
• 13 percent of the sites had three colonies
• 13 percent of the sites had four colonies
• 13 percent of the sites had five or more colonies

One site had 18 colonies! As colonies were being eliminated, new colonies were moving in. It is important to keep Sentricon stations baited, especially in high-pressure termite areas. Termite colonies can move in and out quickly, and even if colonies have been eliminated, it doesn’t prevent termites from reoccurring. With Sentricon with Always Active™ technology, Recruit HD termite bait is installed immediately, so termites can begin feeding on it as soon as they find a station. This starts the colony elimination process sooner and keeps property protection continuous if new colonies move in.

Q: What are the known foraging ranges for termites by species?
A: The foraging range can vary significantly based on the geography, soil type and species. Research papers* cited by the Mallis Handbook of Pest Control, available from the publisher of Pest Control Technology (PCT) magazine, state the following:

Termite species	Known foraging range	Equivalent to
Eastern subterranean termites	0.33 acre	One-third of a football field
Western subterranean termites2	0.33 acre	One-third of a football field
Desert subterranean termites	0.5 acre	Half of a football field
Formosan subterranean termites	0.5 acre	Half of a football field