This article by Jerry Cates, first published on 10 February 2019, was last revised on 19 August 2022. © Bugsinthenews Vol. 20:02(01).
Note: The information shared in this article was derived from decades of experience, and is provided as part of our focus on EcoSystem Forensics.
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.
Those whose homes and trees 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 these 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. Unless that cellulose comes from the rootstock of valuable trees in your yard, their consumption of subterranean stores of cellulosic matter is mostly beneficial, as it primarily functions to enrich the soil.
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 or your trees. If the termites are attacking your home, they should be dealt with via a comprehensive termite control program inside and on the perimeter of your home. 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, though — particularly if Formosan termites are involved — a comprehensive inspection of the at-risk trees in your yard should be carried out to ensure they are not infested. 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 those inspections to another level by opening up wall sections next to bath traps or similar in-home risks to see if hidden infestations are involved, and to examine the heartwood of all your trees that are known to be at risk from termite infestations, to see if those trees are harboring, and being damaged by, termites.
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 utmost respect, which 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.
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 and trees 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 rarely 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 have 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, let’s face it, life — in general — is like that. Everyone who drives the Interstate during rush hour automatically knows about some of 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 and tertiary 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 more than 10-15 years. Before long, the termites in each container had constructed tunnels that criss-crossed every square inch of the soil the container held. Many of those tunnels were positioned directly against the glass sides, so the termites that moved within those tunnels could be seen and studied without having to open the container up. Studying their behavior in this way helped contribute to the author’s understanding of termite biology in a myriad of ways.
The author 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 as their pest management provider. Yet, despite all those termites in the ground, only a few termite infestations in those facilities ever took place. Too, those that did occur 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 seemed to defy all the “rules.”
Puzzlement over this led the author to carry out investigations into why it was so. The answers 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. It should, however, suggest — to those whose privacy fences are supported by wooden posts submerged in the soil — that when they eventually replace that fence they should opt for steel posts instead of wooden ones.
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, unless that wood extends into the above-ground structure of the home. 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. Three of the 12 families are represented in Texas. One of those is composed strictly of termites that are beneficial and is color-coded in green. Species from two other termite families — color-coded in red — regularly attack homes and businesses, though one (the drywood termites in the family Kalotermitidae) is generally confined to the Gulf coast, though wood moved from coastal areas to other parts of Texas is capable of transferring them to their new location, where they are able to thrive under certain conditions. The most voracious termites, whose species do the most damage to man-made structures, are members of the termite family Rhinotermitidae, and one species in that family, the Formosan termite (Coptotermes formosanus) attacks the heartwood and living tissues of our trees as well:
- 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.
- 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.
- Cratomastotermitidae (Bechley, 2007): an extinct family containing one genus and one species (Crematomastotermes wolfschwenningeri).
- 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).
- 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.
- 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.
- 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).
- 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.
- 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.
- Stylotermitidae (Holmgren & Holmgren, 1917): a family of termites having two extinct and one extant genera, and about 50 species.
- 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.
- 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.
- 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.
- 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.
- 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.
- Corner Wedge Cracks. On exterior walls of brick or stone veneer, diurnal heating of the wall in the summertime cause 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.
- 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.
- 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.
- 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.
- 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.
- 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.
- 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.
- 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.
- 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.
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