[Technically Speaking] When science is confounding

I have spent nearly eight of my professional years doing research mainly in the laboratory with various “structural pests.” I often have made observations in the lab that are inconsistent with observations I made in the field. There are many reasons for this and it is important for us as pest management professionals and as “field researchers” to understand why these differences exist and which information we use to make operational decisions, e.g., what products to use, what application technique, etc.

FIELD RESEARCHERS. The first question you may have is why do I view pest management professionals as “field researchers”? Every year we are presented with a variety of new products — and to some degree they have been tested in the lab and/or field. I’m not saying that manufacturers do not do field tests under Experimental Use Permits (EUPs) sanctioned by the U.S. EPA, but these are typically for new active ingredients or new application sites for registered products and they are generally very limited in scope. However, they are field studies.
But many of the products marketed to the industry undergo limited testing before they are brought into the marketplace. The “real world” is a different test site than a chamber in a researcher’s or manufacturer’s lab bench where the insects are confined to a chamber and have to make prescribed choices.
While it is important information to know that if you spray an insecticide on bed bugs or force them to walk across treated panels a product will kill them; it doesn’t mean the product will be effective in the field. Field tests in the hands of technicians and in bed bug- infested apartments is critical in answering how well a product will work against bed bugs. Thus, the lab test is a precursor to work that really needs to be done in the field.
The real world involves putting the product in the hands of technicians and seeing how it performs. In the real world, how accessible is the product to the target pest?
• We encounter surface types where products can be absorbed (carpeting and wall-
paper), run-off (hardwood and sheet vinyl) or puddle.
• Products may have differing degrees of volatility, making them more or less effective when applied into cracks and crevices.
• The method of application, such as a liquid or an aerosol, may affect target pests’ behavior, causing them to disperse.
• The type of formulation — liquid, aerosol or dust — may affect pest behavior and availability to the pest in the field.
• The environment affects the type of application that can be performed. The amount of clutter, the presence of children’s clothes and toys, and the presence of pets may affect how a product can be used.
We have gone through various periods of product evaluations in the field. The most notable and recent of these is the aversion associated with cockroach baits. This was a situation discovered by pest management professionals and brought to manufacturers’ attention. As a result of pest management professional field research, cockroach baits are in their third evolution and I suspect there will be a few more.
In some situations, laboratory tests may demonstrate an effect that is not borne out in the field. Field studies and our experience may tell a different story. A case in point is a recent article in the Journal of Economic Entomology that presented research on the 10-week response of Formosan termites to baits or non-repellent termiticides in an extended foraging arena. The article abstract stated:
• All termites were killed by noviflumuron baits, whereas the non-repellent termiticides fipronil and thiamethoxam divided the laboratory populations into two groups after causing 25 to 35 percent worker mortality.
• The horizontal transfer of lethal effects of fipronil was less than 5 meters.
• Because of their dose-dependent lethal time, non-repellent termiticides did not fulfill the requirements of a liquid bait model.
The article’s concluding comment is perhaps the most telling as to the study’s intent: “If C. formosanus populations are to be managed, there is a need to use a control measure that can kill the entire colony.” If all we rely on to make a decision about a product to control Formosans is the information presented by this study, then we would conclude that noviflumuron is the product of choice.

FIELD STUDIES. Looking at field studies is another way we could approach this decision-making process. If we look at the Gulfport Field Studies for protection of structures in simulated field tests against native subterranean termites (I know these are not Formosans), fipronil has provided termite protection in the ground board and concrete slab tests in all test sites for 11 years and six years to date (depending on the formulation). Personally I’m more interested in how the product works in the field and to what degree it benefits my customers. Is not the ultimate goal of any termite product we use to prevent further damage to our customer’s home? The gold standard is how we use that product and how it performs in the field not in the laboratory. I’m not questioning the observations made in the study or the findings, but I find it a bit of a stretch to imply that using noviflumuron that kills the entire colony is the only way to manage Formosan termites. PCOs have a wide range of effective products in their “toolbox” to control both Formosan and subterranean termites, more than at any time in the industry’s history, and I’m certain there will be more in the future.
I wholeheartedly support laboratory research as a precursor to field research and we have a lot of university programs and private researchers making significant contributions to our industry. However, we need to be cautious not to jump to any conclusions based on laboratory studies unless they are backed by field research.
We should be wary of marketing strategies that use laboratory research in this way. When making decisions about the products you use, PCOs need to take into account information from refereed journals, manufacturer data and product literature, EUPs and you and your peers’ own “real world” experiences.

The author is president of Innovative Pest Management, Brookeville, Md., and be contacted via e-mail at rkramer@giemedia.com.