Signs of Spring 4: Termites

Photo by S. Bauer, USDA

Photo by S. Bauer, USDA

When Deborah and I were in graduate school at the State University of New York College of Environmental Science and Forestry in Syracuse (better known as SUNY-ESF!), Deborah, as a student in entomology, took the graduate level, insect taxonomy course. One aspect of the course was for each student to put together an insect collection. To make it interesting, the instructors promised to reward the best insect collection (as measured by the largest numbers of types of insects) with a bottle of wine (ah, grad school!)). Deborah dug into the collecting and pinning and displaying of her insects with great enthusiasm. There was one thing, though, that was holding back her collection diversity: there were no termites in upstate New York! The long, very cold winters prevented colonies from becoming established.

Termites, back then, were classified in their own insect order called “Isoptera.” It was important for the diversity and quality of the collection to have representatives from as many orders of insects as possible. I have just learned, however, that this classification may not be accurate any longer. It turns out that termites are evolutionarily closely related to cockroaches and are now included as a mere sub-order or super-family within the Order Blattodea! (Deborah had, mostly from living in a series of college-level apartments and houses, MANY representatives of Blattodea in her collection!).

Anyway, back to the comfortable past when termites were termites and not relatives of roaches! In order to add to a little polish to her collection diversity (and, eventually, to allow her to win that bottle of wine!) she asked a friend who was going to visit his family in (where else?) Pennsylvania, if he would mind looking around in some decaying logs or crumbling houses to find her a few termites. Pennsylvania, as many of us who live here know, is an ideal habitat for termites.

So we flash forward twenty years and Deborah and I are living amongst the termites here in Western Pennsylvania. We had seen termites in downed logs in our woodlot and orchard, and they had even shredded up some wooden posts I had used when building our dog-yard fence. They seemed, though, to be keeping their distance from the house, and almost every time I see one I think of having a nice glass of wine! Then one afternoon in our dining room, I picked up a cardboard box full of teaching handouts and cardboard cut outs of insect body parts and legs and wings, of all things, and was surprised to see movement in the box and shredding of the edges of the cardboard. We followed a trail through the gaps in the flooring down into the basement where we saw the characteristic, packed soil tubes (pictured below) of our local termite colony etched into the wood of the floor joists and extending out through gaps in the foundation. We, of course, reacted like good biologists …. actually not, we were horrified that our house was under attack and looked around for poison, any poison that we could use to dispatch the invaders.

Photo by J. Conrad, Public Domain

Photo by J. Conrad, Public Domain

We calmed down and called a termite service and signed up for a long-term, non-pesticide termite control system. Traps were placed out around the east side of the house where the termite activity was greatest. In the traps were bits of wood of a type that was proven to be irresistible to termites (the technician wouldn’t tell us what types of wood it was. He said that it was a company secret). The plan was once the termites started munching on the wood in the traps, a chemical that acted as an anti-reproductive hormone would be introduced into the wood chips. The feeding termites would take this hormone back to their main nest where the entire colony would be subsequently neutered and destroyed.

It took over a year and a half for the termites to find and begin to chew on the “irresistible” wood chips. During that time we didn’t see any more termite activity in the house (we also didn’t put anymore cardboard boxes of papers on the floor next to the east wall of the dining room!) The technician applied the hormone and we continued to see no termite activity through the remaining two years of our contract, and we have continued to not see any termites in the house for these past 18 years (although the fallen branches of the apple and pear trees in our orchard (about 30 feet to the west of our deck) are quickly degraded and decomposed by termites. I think termites REALLY like apple wood! Maybe I should pass that observation on to the termite control company!

The termite technician told us that there was a great deal of termite activity all along the towns of the Kiski River Valley. He said that they speculated that there was, in fact, one gigantic colony of termites that were feeding on the fallen wood (and standing houses) of Apollo, Vandergrift, and Leechburg. The image of a vast, highly interconnected super-colony humming along just beneath the surface of the soil was both exciting and horrifying (depending on whether I was thinking like a biologist or a homeowner).

A recent article in the New York Times (which Lisa Meyerhuber passed along to me) talked about the importance of tropical, African termites in generating a soil structure that not only resists wind and water erosion but also retains a large percentage of a site’s annual rainfall. In desert ecosystems this water retention along with the very fertile accumulation of termite feces can make the soil around termite mounds into an oasis that can support vegetation and animal life far above levels seen in the nearby, non-termite worked soil.

Photo by BBC.co.uk

Photo by BBC.co.uk

There was another African termite story a few years ago, too. In the Namib Desert of western Africa the sparse vegetation grows in great rings that can be forty feet across with extensive areas of barren soil areas in between. This odd and visually compelling plant growth pattern was finally explained as the consequence of subterranean, sand termites feeding on plant roots and altering the soil around them to divert and retain the scant rainfall of the Namib into ring-shaped micro-reservoirs. Plants then could grow roots into these micro-reservoirs and, thus, ended up growing in these unusual and very persistent rings. This explanation is quite pleasing on an ecological level but pales in scope and terror next to the native, Himba people who felt that the plant rings were either the footprints of gods that had walked across the desert or relics from the poisonous breath of a giant dragon that lived underground out the Namib.

So, are we sitting on top of a giant termite colony here in the Kiski Valley? Are these termites working the soil into a high level of fertility and stability? Is it worth putting up with a little structural damage (and cost) to have these social insects do their wood decomposition and soil burrowing activities?

What wonderful questions! Or should we look around for some dragons?

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1 Response to Signs of Spring 4: Termites

  1. Robert steffes says:

    i remember seeing those rings flying over the Namib on the way to South Africa 30 years ago. Now I know what they are!
    When we moved into an old farmhouse here in Aliquippa, a pest control guy told me that termites tend to cause problems for homeowners when they don’t have access to decaying wood readily available outside, as in cities. Also the little devils are attracted to moisture, so keeping drainage adequate was an important method of control for them and carpenter ants. Social insects rule!

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