Texas Termites: How to Keep Them Honest..

This article by Jerry Cates, first published on 10 February 2019, was last revised on 27 May 2021. © Bugsinthenews Vol. 20:02(01).


The very word “Termite” strikes fear in the hearts of most homeowners. That natural fright is based on the well-known fact that a few termite species regularly cause serious damage to man-made structures, while several hundred more sometimes damage crops, shrubs, and trees. On the other hand, most of the 3,106 species of termites currently recognized — some of which are termed agricultural termites because of their affinity for live grasses and other forms of growing plant life — pose little or no economic danger to mankind’s possessions, usually including the crops those termites may attack.


Fig. 1. Agricultural termites construct fecal sheaths over grasses and other soft, easily masticated forms of plant-life. Safely inside these humidity-controlled structures they feed on the cellulose-and-lignin-containing tissues of these plants. Termites in this family (Termitidae) include the desert termite, Gnathamitermes tubiformes. Their mandibles are weaker than those of termites that attack wooden structures, which prevents them from causing widespread damage, but the microbes in their intestinal tracts are more efficient at digesting lignocellulose.


Those whose homes are subject to termite damage have good reason to fear these insects. This is true particularly in those places where environmental conditions favor the propagation of the more voracious termite species. Yet, even in those locales, it is important to recognize that not all of the termites inhabiting the soil of a yard pose those dangers. Furthermore, even when a species that is known to pose such a danger is discovered nearby, the risk to homes, growing crops and living shrubs and trees may be minimal simply because that specific termite colony may be senescent. Young colonies are more robust than older ones, sort of like people. But even youthful, robust termite colonies can become so enamored with other, abundant sources of cellulose submerged in the ground, that its workers have no interest in consuming cellulose from anywhere else.

Termite Swarms…

What about termite swarms? Termite colonies swarm once they reach a certain stage in their colonial development. When they swarm, their winged reproductives (kings and queens) emerge by the hundreds or thousands from the colony’s workings, intending to fly into the sky, mate with other reproductives, and search for a site to start a new colony. Usually the swarm lasts one to three days, though sometimes it will last a week or more. Most of the time the swarms emerge from the ground outside your home. Sometimes, though, they will emerge inside your home. If you have a termite swarm inside your home, what does that mean, and what should be done?

Obviously, what a termite swarm means is that a termite colony is close by. What it does not necessarily mean is that the termite colony is presently attacking your home. If the termites are attacking your home, they should be dealt with by having your home treated for them. But that should only be done after an inspection by a professional that confirms the presence of active termites. It is relatively common for termite reproductives to be found inside a home that is not presently under attack. If no active termite infestation can be found in the process of a visual/palpated inspection, and only a few termite reproductives have been seen, a termite treatment is generally not indicated. If a larger number of termite reproductives are seen, but no evidence of an active termite infestation can be found, it may be worthwhile to take the inspection to another level by opening up wall sections next to bath traps or similar risks to see if hidden infestations are involved.


Note: What I post here may be interpreted by some as downplaying the risks termites pose to homes in Texas. That is not my intent. Termites should be given the respect they deserve. At the same time, though, the sensationalism some attach to them is often “over the top.” I remember, years ago, reading about a celebrated insurance salesman who sold the most life insurance in his office because he knew how to “back the hearse up to the front door.” By doing so, he could entice his prospects to buy more life insurance than made good sense. Sales personnel who are able to sell refrigerators to eskimos are celebrated, too, even if the eskimos have no need for their products. When termite specialists overemphasize the risks that termites pose, they may entice their prospects into getting a termite treatment when none is required. That’s unethical. My purpose here is simply to point out when termite treatments are indicated, and when they are not. I also go one step further, to help you, the average Texas homeowner, do your own inspections for conditions conducive to termite infestations, so you can do you part to avoid termite infestations that can, and should, be prevented.


Keeping Termites Honest

Even more important, though, is the fact that — with a little research and a modicum of elbow-grease — most Texas homeowners can reduce the risk of termite attacks on their homes to nearly zero, even in the midst of young, vibrant colonies of the most voracious termite species around.

That’s what the author refers to as “Keeping Termites Honest.”

Because of their bad reputation, many think termites are all bad. Nothing, though, is further from the truth. Termites, including those with the worst rap sheets of all, were not made to destroy our homes. They consume cellulose and lignin, in the form of dead or decaying plant tissue, to stay alive. In their natural environments they pay us a huge favor by turning fallen trees and shrubs, and other plant life, back into the soil nutrients living botanicals need to stay healthy. They get in trouble, and cause us grief, only when they wander outside that narrow niche and feed on the finished timbers, floorings, and wallboards of man-made structures.


Fig. 2. Formosan Termite Carton Nests in the walls of a bathroom at a home in Austin, Texas. The carton nest is evident in the photo as what looks like cardboard matting (note the square section of carton nest, lifted from the section in the upper left quadrant of the photo and placed on top, at the upper center of the image). Treatments of homes infested with this species of termite require special skills honed over decades of practice, methodologies developed over that same time frame, and specialized equipment tailored to the job. When you examine this image closely, what you see may make you think a genuine calamity has taken place, one that is likely beyond correction. If so, your reaction will be typical. Truly, a calamity did take place, but not one that cannot be fixed. Still, even seasoned termite control specialists refused to tackle this termite job, thinking it was impossible to warranty. Well, here’s the good news: the homeowner still lives here, the termites that caused all this horrible-looking damage are history, and repairs to all the infested areas are underway. None of the walls have to be completely rebuilt, though some studs need reinforcement. A fully renewable 2-year warranty, provided with the treatment, covers the whole structure…


Fig. 3. Native subterranean termite shelter tube. This home was infested with Reticulitermes flavipes, our native Eastern subterranean termite. Several termite shelter tubes were found on the foundation, including the one shown here, in a corner, at the center of the image. The colony was quite robust, and possibly emanated from a termite infestation that began in cellulosic debris left under the home when it was built. In this case, the termites later chose to attack the home, even to the point of building wide, multi-lane shelter tubes that covered 12 inches or more of the foundation leading from the soil to the interior walls of the home. In the vast majority of cases, however, that does not happen; the termites are happy just munching on the wood in the soil, and leave the home, itself, alone.


So, how do we keep them honest, strictly confined to those pursuits that benefit us and the ecosystems they occupy? By following a few simple rules in and around our homes. Specifics on that front will be explained later in this article, in the section titled “Conditions Conducive to Termite Infestations.” If you disregard those rules, you open the door for termites to inflict damage. Obedience to them, though, is often enough to ensure that the termites in our midst perform admirably as important recyclers of nature’s accumulations of cellulosic debris, without munching on our homes in the process.


IMPORTANT: Certain conducive conditions are built into the designs of practically all homes, and others are built into the designs of some homes. For example, (1) if you have a ground-floor bath tub, the drain from the tub through the foundation is contained in a 12×12 inch portal leading to the soil underneath; this allows termites a quick path from under the home to enter the house undetected, but so do all the other plumbing penetrations in the foundation, so I never recommend treating this area preventively; if termites ever get into a home, though, this and all other plumbing penetrations should be treated as part of the termite control plan. (2) Some architects really don’t like to have any part of a home’s foundation showing, and plan the landscape so the soil meets or covers the joint between the foundation and masonry veneer; if the landscape is set so the soil level is permanently over this joint, it can be very expensive to correct it. (3) The cost of copper pipe has gone up, and that, along with the warming trends of the early years of the new millennium, has led many builders to opt for plastic plumbing in the walls, subfloors, and attics, rather than using copper pipe in the foundation itself; this reduces the risk of native subterranean and Formosan termites coming up from the soil, but increases the risk of Formosan termites in roofs and attics because — along with this plumbing — the undersides of the roof has to be insulated, usually with foam, which increases the risk of moisture collecting in the roof decking, an invitation to Formosan termites in those areas. SUMMARY: In many if not most cases, these designed-in conditions cannot easily be mitigated until termites show up, so it is not possible to remove all the risks of termite infestation, no matter what you do. But, hey, life is like that. Try driving the Interstate during rush hour, then let’s talk about the other risks attending ordinary living…


Termites in Texas Soil: Just What Nature Intended

Now, though, let’s get a better grip on what all the foregoing means, and why it matters. Finding termites in the soil, just about anywhere you go in Texas, is a wholly natural condition. In many ways the presence of termites in a yard is a strong indicator of a healthy ecosystem. In most Texas yards a person can usually collect gobs of live termites in short order simply by burying a piece of wood in the ground.

Through the late 1980’s and much of the 1990’s, the author followed a monthly circuit throughout most of central, west, and east Texas. Research he was conducting for a series of patent applications led him to hammer short wooden stakes into the soil around the perimeters of the Texas nursing facilities that he regularly serviced along that route. Every month, for several years in a row, he pulled up those stakes to inspect the part of each one that had been buried.

Before long termites were present in practically every stake, munching away at the wood. Whether in the arid deserts of west Texas, the wetlands of east Texas, the Red River Valley of North Texas, along the Texas Gulf Coast, nestled in the hill country or situated on the central plains, termites got into nearly every stake, usually within a short time. Before long he’d collected large numbers of termite workers and pseudergates (secondary reproductives, feeding alongside ordinary worker termites, that — in the absence of a queen in the colony — are able to assume the role of producing eggs and keeping the colony alive) representing dozens of separate termite colonies from practically every ecological province found within the continental United States. Most were members of one of the three then-most-common perpetrators of termite damage in manmade structures in Texas.

Those collections, which constituted satellites of their original colonies, were then studied at length in the laboratory. To keep them alive, the author provided enough soil from each colony’s collection site to fill 3/4ths of the 5-gallon glass containers in which they were kept. Each was fitted with a tight lid that kept humidity levels and concentrations of carbon dioxide needed by termites, inside each container, relatively steady. Many managed to remain viable for 10-15 years. Studying their behavior helped contribute to the author’s understanding of termite biology in a myriad of ways.

He handled all of the pest management needs for the nursing centers along that route, and treated all the termite infestations that were discovered during his tenure. Yet, despite all those termites in the ground, only a few termite infestations in the facility buildings ever took place. Those that occurred were limited in scope. Since this took place over a period of about 25 years, and the entomologists at Texas A&M project that Texas homes have a 70% probability of being infested with termites within every 25 year stretch, this finding defied all the rules.

His puzzlement over this led to investigations into why it was so. The answer came, not from the facilities the termites shunned, but from those few they attacked. In almost every one, sub-par facility maintenance, inside and out, led to conditions that welcomed termites to dinner. As a rule, most residential homes are less well maintained than the typical Texas nursing facility, and that explains a lot. If you are a homeowner, take this to heart. Do not neglect the maintenance of your residence. If you do, the consequences can be much worse than you may imagine.

Garden Stakes and Wood Fences

Many Texas homeowners garden with wooden stakes, and even more have back yards bordered with aging wooden fences whose staves touch the ground. Some fences are supported on wooden posts buried in the soil. For the attentive but naive homeowner, pulling up a garden stake or inspecting a backyard fence can be scary. On seeing active termites in such places, a sense of fear and dread often results. Don’t fall victim to that… Termites in a buried wooden stake or on the outer surface of a wood fence is as natural as birds chirping in the springtime. It does not mean that the homes, trees, and crops nearby are in immediate jeopardy of termite damage.

In fact, merely finding termite activity in wood that has been in contact with the soil should never, by itself, be used to justify treating a nearby home for termites. To the wise, however, it does provide a gentle reminder that Texas hosts termites that — when circumstances are right — can wreak havoc, and that reminder can serve to warn against complacency. Yet, most homeowners give little thought to such matters, and many of them still never get termites in their homes. Let that fact ease your mind in case the termites you find in your yard evoke in you a touch of sub-clinical paranoia.

Our native subterranean termites tend to focus on easy-to-access cellulosic food sources. So, as long as those foods are handy, they are not as likely to go after sources that cannot be accessed with ease. Still, such colonies that today are feeding on wood that is not directly connected to a home will eventually deplete the easily accessible wood supplies. When that happens while the colony is still young and vibrant, its workers will turn their attention elsewhere. Homes that provide “welcome mats” for those workers are usually their first victims. For that reason, homeowners should take steps to protect their homes by eliminating conditions conducive to termite infestation. Where termites are concerned, a mild case of sub-clinical paranoia isn’t all bad, especially if it spurs you to take a few preventive measures in your spare time.

We’ll discuss how to conduct those preventive measures later in this article. But first, let’s delve into the vagaries of termite biology.

Comparative Termite Biology in a Nutshell…

The termites are closely related to cockroaches, and — as mentioned earlier — comprise over 3,100 different species worldwide. Most are not only harmless to humans and their worldly goods, but are highly beneficial members of the ecosystems within which they thrive. At present, 12 separate taxonomical termite families are recognized, each with one or more species. Two of these families are fully extinct, but 10 are still going strong.

Below is a list of these 12 families, arranged alphabetically, along with short discussions on their habits and descriptions of representative species.

  1. Archeorhinotermitidae (Krishna & Grimaldi, 2003): an extinct family of one genus and one species (Archeorhinotermes rossi). This species is known only from fossils found in Burmese amber.
  2. Archotermopsidae (Engel et al., 2009): an extant family of primitive termites consisting of five extant genera and 13-20 living species. Known generally as dampwood, or rottenwood termites, they only eat wood that has a high moisture content and thus is either actively or on the verge of rotting. For that reason, they do not generally pose a risk to manmade structures that are not already damaged by wood rot. In the United States, the species Zootermopsis angusticollis, commonly known as the Pacific dampwood termite, is mostly found in California, Oregon, Washington, Idaho, Western Nevada, and southern British Columbia, but not in Texas.
  3. Cratomastotermitidae (Bechley, 2007): an extinct family containing one genus and one species (Crematomastotermes wolfschwenningeri).
  4. Hodotermitidae (Desneau, 1904): an extant, though ancient Old World family of termites consisting of three extant genera and 18-19 species found in the deserts and savannas of Africa, the Middle East, and Southwest Asia. They are colloquially known as harvester termites because of their habit of collecting grass (a habit not confined to this family of termites, however).
  5. Kalotermitidae (Froggatt, 1897): an extant family of primitive (morphologically) termites comprised of 21 genera and 419 species. They are cosmopolitan insects commonly known as drywood termites. In Texas, three species of drywood termites can be found, mostly within a narrow band bordering the Gulf coast. The most common species, Incisitermes snyderi, produces nocturnally-swarming, light colored reproductives with uniformly transparent wings whose bodies are 7/16 inches long; the bodies of their soldiers are about 5/16 inches long with dark, yellowish-brown heads whose strong mandibles project conspicuously forward. Cryptotermes brevis, another drywood termite found along the Texas Gulf coast, produces reproductives that are similar to those of Incisitermes snyderi; their  soldiers, however, have dark, cubical heads with short mandibles. Incisitermes minor, the least common of the drywood termites found in Texas, produce diurnally-swarming reproductives with dark bodies approximately 9/16 inches long and wings that range from clear to brown; its soldiers are similar to those of I. snyderi. Drywood termites are often imported to areas where they are not normally found; this commonly occurs when wooden articles infested with them are transported elsewhere. 
  6. Mastotermitidae (Desneau 1904): an extant family of termites that once was found worldwide, but that today survives with only a single living species, Mastotermes darwiniensis. This species is found only in northern Australia.
  7. Rhinotermitidae (Froggatt, 1897): an extant family of wood-consuming termites comprised of eight subfamilies, 15 genera, and 345 described species. Among their species are the most voracious termites found in North America, in terms of the danger they pose to man-made wooden structures. These include Coptotermes formosanus (commonly known as the Formosan termite, which has been found along the Gulf Coast for many years and is now gaining a foothold in many other parts of Texas), Coptotermes gestroi (the Asian termite, now found in parts of southern Florida, but not presently found in Texas), Reticulitermes flavipes (the eastern subterranean termite, found throughout Texas), R. virginicus (the dark southern subterranean termite, found throughout Texas), R. hageni (the light southern subterranean termite, found throughout Texas), R. tibialis (the Midwestern subterranean termite, found in many parts of Texas), and R. hesperus (the Western subterranean termite, found mostly along the west coast of the United States).
  8. Serritermitidae (Holmgren, 1910): an extant family of wood-consuming termites comprised of a few species found in South America. Their habits are similar to those in the family Rhinotermitidae.
  9. Stolotermitidae (Holmgren, 1910): an extant family with two extant genera and about 10-14 species found in Australia, sub-Saharan Africa and the Neotropics. This is a relict lineage of primitive termites, and are sometimes known as dampwood termites.
  10. Stylotermitidae (Holmgren & Holmgren, 1917): a family of termites having two extinct and one extant genera, and about 50 species.
  11. Termitidae (Brulle, 1832): an extant family of termites. Evolutionarily this is the most specialized, due to the ability of their gut to degrade lignocellulose with a greater efficiency than the species of other termite families. They are thus known as the “higher termites.” The family is comprised of eight subfamilies, and several are found in Texas. Gnathamitermes tubiformans (the desert termite) is one of the largest termites found here, and is the most common termite in western Texas, New Mexico and Arizona; the species does not damage man-made structures, and is considered beneficial for its conversion of plant matter into soil nutrients, and because its nesting behavior improves soil structure and moisture retention. 
  12. Termopsidae (Grasse, 1949): an extinct family of one genus consisting of eight species found in the fossil records of China, Canada, Labrador, France, and Colorado, USA.

Like their close cousins the cockroaches, from which they evolved some 130 million years ago, termites are excellent survivors. The queens of some species have the longest lifespans of any of our insects, with some living 30-50 years or more.

Conditions Conducive to Termite Infestation

Homeowners can do themselves and their homes a huge favor by inspecting for and eliminating conditions at their homes that invite termite infestations. You don’t need to be an expert to do this (though you do need to conduct it with a certain degree of dedication, as missing something important can result in a painful lesson later on), it takes only a little of your time, and the benefits are enormous.

When you inspect, look for the following conditions and take corrective action where you can. Some conducive conditions cannot be easily or practically rectified. In those cases, don’t panic, but do conduct regular inspections of the affected areas so, if termites do show up, you will be able to recognize their presence and call in a professional to deal with them.

  1. Form Boards Against the Home, in Contact with the Soil. Form boards (usually of 2×4 or 2×6 lumber) are used to delineate a home’s concrete foundation prior to having the foundation poured. They are left in place while the foundation is poured. Once the concrete hardens and cures, these form boards are supposed to be removed. They become a condition conducive to termite infestation when they are left in place, as they give termites a source of good-quality cellulose, in the soil, right next to the home’s foundation. Check around the perimeter of your home to see if partially submerged wood lumber is present at any place along the perimeter of your home. This is especially problematic if a piece a lumber projects above the foundation so that it overlaps the gap between the foundation and the masonry or exterior siding. When that happens, termites can infest the siding or the interior of a masonry wall by entering behind the board without being seen. If you see form boards in place at your home and the builder is still responsible for corrections, have the builder take steps to get them removed immediately. If the home is out of builder’s warranty, remove them yourself, right away.
  2. Wood Fence in Contact with the Home. Ideally a wood fence should not touch the home it protects, but should have at least a 1/4th to 1/2-inch gap between the fence and the structure. Wood fences that are built against a home’s foundation, such that they obscure the junction between the foundation and the masonry or siding that is above the foundation, present the same conducive condition mentioned above for form boards. If the fence cannot be repositioned so it doesn’t touch the home, you need to watch this area closely to make sure you discover termites there if and when they arrive. If active termites are found elsewhere in the building, leading to a treatment of the structure, this and other conducive conditions should be included in the treatment plan.

    Fig. 4. This fence is made of recycled plastic, and is not itself at risk of termite damage. Still, it obscures the outer wall of this residence in a way that makes it difficult to inspect for termite shelter tubes on the home’s foundation. Note, too, that the soil at this location also obscures the home’s foundation, making for significant opportunities for termites to get into the home’s walls without being seen.


  3. Wood Pile, or Brush Pile, in Direct Contact with the Home. A wood pile or brush pile in direct contact with the structure is a conducive condition if the wood obscures the gap from the soil to and beyond the upper surface of the foundation. Actually, a wood or brush pile on the ground, anywhere near a home invites termites in large numbers. Remove all wood piles that touch the ground, and only store fire wood on metal racks, 6-12 inches off the ground, away from the home and never against a wooden fence.
  4. Corner Wedge Cracks. On exterior walls of brick or stone veneer, diurnal heating of the wall in the summertime caused the wall to expand much more than the cooler foundation on which it sits. The result, oftentimes, is a corner wedge crack on both sides of the corner where two exterior walls meet. Sometimes the crack extends into the soil, providing termites a way to enter the home without being seen. Though some recommend getting these repaired, the likelihood is that a repair will be defeated before long by the same situation that caused it initially.

    Fig. 5. A Corner Wedge Crack. This foundation defect is common in homes with brick or stone exteriors. The foundation stays relatively cool throughout the day, while walls exposed to the sun heat up and expand. The horizontal expansion of the wall stresses the foundation at its corners. Here the stress caused by the differential expansion cannot be fully absorbed by the foundation at the corners. Eventually, a wedge of foundation pops off to relieve the stress. Often, as in this case, the wedge crack extends into the soil, potentially providing a pathway for termites to enter the structure unseen. Although many construction companies suggest repairing these cracks, it is likely they will return later. When a termite treatment is performed at a home the soil below and/or the wall section above this corner wedge crack need(s) to be treated to prevent termites from entering at this location.


  5. Soil, mulch, or decorative rock/gravel too high. Several inches of your home’s foundation should be visible, all along its length. 4-5 inches or more is optimal, but if that cannot be done, at least 1-2 inches of foundation should be kept free of soil or other obstructions and inspected regularly for shelter tubes used by termites to travel from the soil into the home. If your home has portions of its foundation obscured by soil or other obstructions, get that fixed. Doing so may be as simple as using a hoe to move the soil away from the foundation perimeter.

    Fig. 6. Foundation obscured by decorative rock. The bottom layer of brick is right at the soil/rock line here, but the decorative rock obscures just enough of the junction between the brick and the foundation to allow termites to get in unseen.


    Fig. 7. Soil too high. Notice that the soil covers the masonry/foundation junction all along the length of the stone wall, but only at the corner of the brick wall. At least a few inches of foundation should be showing all along its perimeter so shelter tubes built by termites to enter the home will be visible.


  6. Landscape too dense. If trees, shrubs, or other botanicals next to the home are so dense that they make it practically impossible to inspect the foundation, termites may construct shelter tubes from the soil into the home without being detected. If your home has portions of its foundation obscured by trees, shrubs, or other botanicals, get that fixed. Doing so may be as simple as using a gas-or-electric trimmer to clip the shrubbery, etc. away from the foundation perimeter, but remember that such remedies are only temporary, as the growing plant will soon resume obscuring the foundation; a better solution is to revise your landscape architecture to eliminate plantings that close to the foundation.
  7. Planter boxes, or add-on masonry steps, placed against foundation. It is not unusual for builders or homeowners to place planter boxes, or concrete/masonry stairways directly against a home’s foundation, creating a cryptic gap that termites can use to get into the home without being seen. If this condition exists at your home, pull the planter box out, away from the home’s perimeter, so at least 6 inches of gap is provided for inspections. Better yet, remove all planter boxes from your home’s perimeter entirely.

    Fig. 8. Brickwork add-ons placed against foundation and Masonry wall. At this home the original foundation did not provide for the masonry staircase that needed to be placed here to provide access to the utility room door, nor for the cosmetic brick wall enclosing the HVAC. After the foundation was poured, a second pour was made to provide a detached pad for the staircase and HVAC, upon which were then built the masonry stairs and the cosmetic HVAC enclosure. Naturally these abutted the foundation and the masonry wall of the main structure, and when first constructed, the junction may have appeared microscopic. Even then, however, termites would likely have been able to exploit that small crack to get into the home. Now, several years later, the junction is pronounced, as the photo below demonstrates.


    Fig. 9. Masonry staircase placed against foundation. Anytime an add-on structure of any kind in placed against a foundation, the soil at the juncture must be treated for termites.


  8. Defective After-Market Bidets. After-market bidets installed on commodes often leak, sometimes so slowly the leak is not detected until the flooring and — for commodes above the ground floor — the beams and joists underneath are saturated with water. When that happens, the home becomes ripe for localized, above-ground Formosan termite infestations.
  9. Excessive Water Seepage from Tubs and Showers. Water that overflows from bathtubs during playtime with the kids, and that overflows from showers whose doorways permit leaks to the outside, create excessive moisture conditions in the flooring and underlying wood structures.
  10. Roof Leaks. Moisture that leaks into roof decking, or into the wooden members of the roof structure and the attic flooring constitutes a huge attractant to termites, particularly the Formosan termite (Coptotermes formosanus). Roofs should be inspected regularly for evidence of leaks, and any leaks so discovered should be repaired by a professional in the roofing trade as soon as possible.
  11. Defective HVAC Evaporator Condensate Drainage. If HVAC evaporators in the attic are not serviced professionally on an annual basis, or if their condensate drains are not sanitized regularly by the homeowner during the spring, summer and fall seasons, serious high-moisture conditions often result. Condensate drains often clog from fungus, mildew, or mold buildup, which can lead to condensate overflows into the condensate overflow pan. If that overflow pan is constructed without a proper drain it, too, will fill with water and overflow into the attic.

    Fig. 10. Defective HVAC condensate management in an attic can lead to serious termite infestations. The metal pan visible under the evaporator unit in this attic is there to provide a backup reservoir for the condensate water that would overflow from the primary condensate pan, inside the unit (not visible), if the drain for the primary pan clogs. Many later HVAC models use an overflow switch to shut down the HVAC if the primary pan overflows, but earlier units and some later ones, such as the one shown, do not. A short horizontal pipe extends out of the side of the overflow pan (in the lower left quadrant of the image), but is capped instead of leading to a pipe that would drain the pan to the outside. Absent a proper drain, the overflow pan could completely fill with water and overflow into the attic, creating a serious moisture issue that attracts termites. The vertical pipe in the right half of this photo is open at the top and attached to the primary condensate pan drain at its bottom. It is there to provide venting past the condensate trap (the portion of the horizontal pipe to the left that dips down, then up to the vertical pipe in the center of the photo), and prevents air-lock and other potential problems and must be left open to work properly. For the homeowner, however, this vertical, uncapped pipe provide a means for sanitizing the primary condensate pan drain, to help avoid plugs that form from algae, mildew, and mold buildup in the condensate drain pipe. By inserting a funnel into the opening of this pipe, and pouring in 1/4th cup of distilled vinegar once monthly during the hot months when the air-conditioner is in operation, most fungal buildups can be avoided. If the condensate drain plugs, though, homeowners can often remove the plug using a wet/dry shop vacuum, attaching the suction pipe at the far end of the condensate drain pipe, where it drains outside; run the vacuum cleaner for one or two minutes, then check to ensure the clog has been removed. Once the plug has been cleared, regular use of vinegar, poured in at the after-trap vent pipe, should keep the drain clean.


  12. Defective Attic Hot Water Heaters. Hot water heaters in the attic that are not serviced annually to ensure against leaks, can lead to moisture issues as well. If your home has any of these problems, they should be remedied quickly, by a professional in the associated trade. Once a wooden component of your home becomes saturated with water it takes a long time — months or even years — for its moisture content to return to normal, and as long as the moisture content is above normal, the risk of termite infestations is elevated.

References:

  • Bourguignon et a. 2014. The Evolutionary History of Termites as Inferred from 66 Mitochondrial Genomes. Molecular Biology & Evolution, V.32, Issue 2, 2015.
  • Forschler, Brian T. 1998. Subterranean Termite Biology in Relation to Prevention and Removal of Structural Infestation. NPCA Research Report on Subterranean Termites.
  • Gautam, Bal K., and Gregg Henderson. 2011. Wood Consumption by Formosan Subterranean Termites (Isoptera: Rhinotermitidae) as Affected by Wood Moisture Content and Termperature. Ann. ESA 104(3): 459-464
  • Mallis, Arnold et al. 2011. Mallis Handbook of Pest Control, 10th Edition. GIE Media Inc.
  • Pearce, M. J. 1997. Termites, Biology and Pest Management. CAB International
  • Sheffrahn, Rudolph H. 2019. Expanded New World Distributions of Genera in the Termite Family Kalotermitidae. Sociobiology V.66, No. 1
  • Thorne, Barbara L. 1998. Biology of Subterranean Termites. NPCA Research Report on Subterranean Termites.
  • Weesner, Frances M. 1965. The Termites of the United States. National Pest Control Association.
  • Werner, Floyd and Carl Olson. 1994. Insects of the Southwest. Fisher Books
  • Wilson, Edward O. 1996. In Search of Nature. Shearwater Books.
  • Wilson, Edward O. 1992. The Diversity of Life. W. W. Norton & Co.
  • Wilson, Edward O. 1971. The Insect Societies. Belknap Press of Harvard University.

Leave a Reply

  

  

  

%d bloggers like this: