Back before we were told that sunshine and cigarettes were killing us, there was chlordane. Chlordane is a chemical so highly effective as a termite deterrent that even today, many buildings treated 30, 40, and even 50 years ago remain termite-free. Alas, it's gone now, forced out of service by the EPA for all but a few highly controlled uses.

So what does that leave us in the war against termites? The accepted opinion is that nothing available today is as effective as chlordane was, but the following is an overview of the more popular solutions we do have available:

• Boric acid wood treatment. Brushed or sprayed on wood, boric acid can be quite effective if applied properly. The problem is, it's nearly impossible to reach all wood surfaces in a completed house. Thus, boric acid coating is only practical for new homes under construction.
  
• Barrier treatment. This is a modern version of what we did with chlordane, except it uses different chemicals known as termiticides. The basics are the same, with a liquid chemical being pressure-injected into the soil to encircle the house with an unbroken protective barrier ring. Termites must breech the ring to get to the house, but a properly placed barrier is impassable. Some modern liquid termiticides do not bond very well to the soil and so they leach out, while others break down and lose their effectiveness from environmental interaction. In short, the new stuff isn't as good as chlordane was.
  
• Baiting. Termite baiting involves placement of termite bait stations in the soil around the perimeter of your house. For obvious reasons, stations generally use a piece of untreated wood for bait. There is no insecticide in the station until termites are observed feeding on the wood; then the untreated wood is replaced with a perforated plastic tube containing bait laced with a slow-acting termite growth inhibitor. Spacing of the stations is critical because wood bait never actually attracts termites; they just stumble upon it in the course of random foraging.
  
• Non-repellent termiticides. The past few years have produced the most rewarding developments in termite treatment since the introduction of chlordane. Non-repellant liquid termiticides are applied around and under the home, similar to conventional barrier treatments. However, they do not rely on repellency. The older chemicals did work as repellents, meaning that just a whiff of the product was sufficient to send termites on their way. With non-repellents, termites freely forage right through it, then distribute the residuals throughout the rest of the colony as they are feeding, grooming, and interacting with each other. This results in a significantly greater kill rate.

Here is a parting thought: Chlordane was removed from the market because traces of it began showing up in our drinking water. It percolated through the soil and into underground aquifers and streams. Since anything else we inject into the ground has the potential to wind up in the water, bait stations would seem to be the environmentally logical choice.

Some material for this report was obtained from Economypest.com, the University of Kentucky, and the Termite Institute.