[Termite Q&A] Are You Smarter Than a Termite Researcher? (Part 2)

Editor’s note: Last month, PCT magazine published questions and answers with some of the industry’s preeminent experts about all facets of termites and their control: termite biology and behavior, control methods, real-world experiences and more. We didn’t have enough space in the February issue so we held some replies for this month. Following is more from our question and answer session with university and other researchers from around the country.

Our experts:
Dr. Gary Bennett, Professor and Urban Center Director, Purdue University

Dr. Ken Brown, Principal Research Entomologist, City
of New Orleans Mosquito and Termite Control Board

Dr. Brian Forschler, Professor, University of Georgia

Ed Freytag, Senior Research Entomologist, The City of New Orleans Mosquito and Termite Control Board

Dr. Roger Gold, Professor and Endowed Chair, Center for Urban and Structural Entomology, Department of Entomology, Texas A&M University

Dr. Gregg Henderson, Paul K. Adams Professor of Urban Entomology, Louisiana State University AgCenter

Dr. Susan Jones, Associate Professor, Ohio State University

Dr. Mike Potter, Professor/Extension Entomologist, University of Kentucky

Dr. Nan-Yao Su, Professor of Entomology, University of Florida

Dr. Barbara L. Thorne, Professor of Entomology, University of Maryland

What type of emerging technology has the greatest potential for use in controlling termites and why?

Dr. Susan Jones: We need affordable, easy-to-use termite detection equipment to advance termite control methodology. It is important to know where termites are active in order to precisely target a treatment and to assess the effectiveness of a given treatment. Researchers could gain many more insights into termite biology and management if they could reliably and precisely locate termites.

How does a pest management professional find more termites?

Dr. Roger Gold: The best termite “finding method” is a trained, motivated technician. The best technicians are those who want to find conducive conditions, termite damage and live termites. The equipment available today is excellent and effective in the hands of a technician who knows how to use it appropriately. Be careful with high-tech approaches, and have a company policy on when they are used. If you use such equipment in one account, be prepared to explain why you did not use it in Mrs. Jones’ home.

Another concept worth mentioning is that in order to have termites, there must be “conducive conditions.” A technician’s job is not completed until they have defined these conditions, recommended changes and documented them on the inspection form. If the “conducive conditions” are not corrected, the termites will return at some point in time, possibly at your expense.

Is it possible to guarantee to customers that termites will never attack their home?

Dr. Mike Potter: No…thus the reason for and importance of thorough ongoing inspections. We have terrific and reliable products today, but stuff happens….

What causes termites to swarm?

Dr. Susan Jones: The production of swarmers is influenced by the age and size of the colony. The production of winged reproductives (alates or swarmers) is a sign that a subterranean termite colony has reached maturity and usually takes place after a colony is 5 to 10 years old. The colony must have sufficient numbers to be able to recover from the loss of a significant number of individuals that leave the colony as swarmers.

What is the life span of worker/soldier termites?

Dr. Gary Bennett: Termites’ life spans are highly variable since environmental, geographical and colony population factors influence them. It also varies dramatically from one species to another.

How much and what types of disturbances are likely to prompt a termite to flee a particular feeding location?

Dr. Brian Forschler: I am not certain anyone knows the answer to that query. Just like with people, some folks will leave at the drop of a hat and some never, ever go away. Our experience with termite bait stations (that we only watch…we check them once a month but we don’t bait) shows that subterranean termites native to the Southeastern United States rarely visit a bait station for more than five months in a row. With Formosan termites, I have found that when they are newly introduced into an area (less than 10 years after being planted in the new habitat), they will not return to a bait station, a piece of wood or part of a tree — wherever you found and bothered them. They are very skittish.

What factors cause post-treatment termite swarms?

Dr. Nan-Yao Su: When the colony conditions deteriorate, some termites may fly out instead of staying in the nest to die.

What is your opinion of liquid perimeter-mostly treatments?

Dr. Ken Brown and Ed Freytag: There are multiple termite remediation options currently available to the pest management professional. The most widely utilized options include repellent and non-repellent liquid termiticides, baits and fumigants. Several factors go into choosing a remedial termite treatment (i.e., pest identification, construction type, customer expectations, location and degree of infestation/damage).

Selecting the best remediation option for a given property should be a decision made by the pest management professional and property owner after considering these important factors. Non-chemical strategies such as sanitation, exclusion and moisture problem remediation also should be discussed with the property owner.

When the decision to use a liquid termiticide is made based on the previously listed factors, the decision then becomes non-repellents vs. repellents. Non-repellent termiticides offer some distinct advantages over traditional repellent termiticides. First is the issue of avoidance. As the name implies, termites avoid areas treated with repellent termiticides. Because termites continuously forage, it is vital to create a continuous barrier, as small gaps may eventually be located and exploited by foraging termites. With non-repellent termiticides, this problem is diminished, as termites do not avoid the treatment zone. The second distinct advantage is transferability. This issue has received much attention lately and it is important to remember that a given compound may or may not transfer as readily as another. The distance from the treatment zone that a lethal dose can be transferred, as well as the number of individuals that may receive a lethal dose from the exposed individuals, are both important factors and both factors vary between compounds. Another advantage of the “perimeter-mostly” treatment is reduced volume of termiticide applied.

One factor that may seem like a distinct advantage of the “perimeter-mostly” treatment is reduced labor. However, that is not necessarily always the case. It is important to identify and treat the areas within the structure where termites may be entering the building. As we all know, identifying these areas can be difficult and labor intensive. A thorough inspection of the property is critical. Like any termite remediation technology, these products are only as good as the professional applying them.

What does the termite use to decide where to go next? (or, please explain “random foraging”?)

Dr. Gary Bennett: Our understanding of termite foraging is limited, but there are undoubtedly many cues (chemical, environmental, structural, etc.) influencing foraging.

Where is the strangest place you ever found termites?

Dr. Gregg Henderson: The strangest place I ever found termites was in a public school in New Orleans. The school was heavily infested with Formosan termites but I was still quite surprised when I opened up the closet door and then inside the closet was another small bookshelf with doors. When I opened that up I found that all the children’s books were consumed and all that was left was a massive carton nest teeming with Formosans. Quite a site! Another unusual spot was on the levees in New Orleans. I first found them infesting the bagasse (sugarcane waste) seams of the flood walls. When the hurricanes caused the floodwalls to collapse, I followed up on this earlier find and have since found a strong correlation between termite-infested levees and the collapse of the floodwalls and levees that occurred during Hurricanes Katrina and Rita in New Orleans.

What factors cause post-treatment termite swarms?

Dr. Brian Forschler: Bad treatments and moisture above grade would be my first two guesses. Assuming there was a good treatment and there is no moisture above grade, there is no way to answer the question because we don’t know enough about the factors — hormonal, age-related or environmental — that can affect termite metamorphic change.

On what aspect of a termite’s biology and/or behavior is there a need for more research? Why and how will this research ultimately help control termites?

Dr. Susan Jones: Additional field research is needed to determine what affects colony boundaries in space and time. The intermixing of termites from different parental sources has important ramifications for various treatment practices. Additional research also is needed on termite foraging behavior with regard to how termites locate food sources.

On what aspect of termite biology and/or behavior is there a need for more research? Why and how will this research ultimately help control termites?

Dr. Barbara L. Thorne: A ginormous unknown is precisely how termites communicate. If researchers could crack the code and understand “termitese,” we could potentially scramble the insects’ transmission signals and reception pathways, thus knocking them off their game. Understanding how termites inform one another about where to go, what to eat, how the colony’s team will distribute among food resources, when more soldiers are needed, etc., could let us exploit the situation by interfering with communications. The termite language is almost certainly based on chemical and tactile messages, but to date, scientists have deciphered very few of the specific signals or vocabulary.

Why are Eastern subterranean termites found throughout much of the United States while drywood termites are found in much more limited regions of the country?

Dr. Brian Forschler: EST or Reticulitermes flavipes is an invasive species. It is established in many areas of the world where it is not native (in fact, the species was named from specimens collected in 1848 from the Royal Greenhouses in Vienna, Austria) including Canada, Wisconsin, California, Germany, France, Chile and Uruguay. Drywoods are found in every place humans can travel…if you count some of the invasive species like Cryptotermes brevis. The question is about aspects of insect biology that lend themselves to being spread — some species have it and others don’t.

If you were going to look at one location in a house for termites, where would it be and why?

Dr. Mike Potter: Prospecting in only “one location” for termites is obviously risky business ­­— but in terms of likelihood of finding termites, dirt-filled porches and stoops are probably the most common point of entry and discovery, industry-wide. Foam boards, scrap lumber and other debris are often left here during initial construction, and the fill is in close proximity to structural wood. Thresholds and bases of entry doors, as well as directly under and behind these within crawlspaces and basements, are hotspots. So are garage door bottoms, and framing around crawlspace access doors.