Mother's Day Termites

Historically in many parts of Texas and the South, Mother's Day marks the beginning of swarm season for Coptotermes formosanus, known in this country as the Formosan termite. And right on schedule I had my first Formosan termite report of the year yesterday, the day after Mother's day. In the process of working with the PMP who submitted the sample, I learned something that I believe is worth passing on.

When termites swarmers are reported from inside a home, the traditional diagnosis says that the house is infested and needs treatment by a termite control professional. When Wendell Daniel, of All Pest Solutions, brought in yesterday's sample it consisted of wingless Formosan termite swarmers. My diagnosis was that the home in question was likely infested and needed professional treatment, quick.

The problem was that this home had been treated before, in 2006; and a few Formosan swarmers had been found at the home annually since then. What made this especially puzzling was that only a few swarmers were found each year, and they were always de-alated (wingless-making diagnosis more difficult). The neighborhood where the home was located has a known population of Formosan termites. The homeowner has never seen any damage, and Mr. Daniels has never been able to detect any sign of activity at the home apart from a few indoor swarmers each year since 2006.

Puzzled, I called Dr. Rudi Scheffran at the University of Florida Research Center in Ft. Lauderdale--the termite capitol of the U.S. Besides being one of the leading termite experts in the country, Rudi is always willing to help and just one of the nicest guys to work with. After confirming with him that the termites I had were indeed Formosans, Rudi told me that even a first year colony in a home will typically launch a couple of hundred swarmers. Putting two and two together, we finally concluded that the termites being found indoors likely entered the home (accidentally) from outdoors, something that would rarely if ever be expected to happen with Reticulitermes, our native subterranean termites.

The reason an accidental indoor collection of Formosan termites is a more probable occurrence than for our local species is that Coptotermes are nocturnal. Being nocturnal they are highly attracted to outdoor lights. In our problem house the homeowner had gone in and out of the front door the night before, a streetlight (the only one on the street) is outside this home. The fact that the same pattern had occurred for four years in a row with no increase in swarmer number helped convince us that this home may not have been infested after all.

My lesson, at least with Formosan termites, is that I shouldn't jump to conclusions about an indoor infestation when one or a small number of swarmers are found indoors. As I thought about it, the very first record I have of Formosan termites in our area in 1999 came from a sharp-eyed homeowner who noted these large, suspicious looking winged insects on her kitchen window screen. These are not your ordinary termites, and the old rules don't all apply. It is not unusual for a nearby colony in a tree or railroad tie or other site to put out large numbers of termites. For several years we monitored swarms outside a north Texas home. It was not unusual for us to collect several gallons of termites in a week during swarming season.

Any termite swarming reports over these next few weeks should be checked out very carefully. Although Formosan termites are not common in Texas away from the upper Gulf coast, they have been reported from scattered sites throughout central, east and north Texas. If you find a suspicious or confirmed case of Formosan termites, please let me know. I do maintain a database of all known sites of Formosan infestation. As Dr. Scheffran so gloomily predicted yesterday, "in 50 years they will probably be all over". But in the meantime I'd like to know where they are, in case our state ever wakes up and determine to something about this very important new pest.