Termites belong to the insect order Isoptera. In nature, termites are considered beneficial insects because they break down dead and dying plant material. Termites are considered pests, however; when they feed on wooden structures. Four types of termites occur in the United States: subterranean, Drywood, Rottenwood, and agricultural termites (sometimes called grass termites or deser termites).
Subterranean termites of the family Rhinotermitidae in the genus Reticulitermes are the kind most commonly encounteed in the United States. Hoever, the most destructive subterranean is probably Coptotermes formosanus, the Formosan termite, which is an introduces species. Even through Drywood Incisitermes and Cryptotermes (Kalotermitidae) and Rottenwood Zootermopsis (Termopsidae) termites do not occur as often, it is importantant that Imperium be able to identify all these types of termites for our clients. Rottenwood termites only infest wood with high moisture content, and are found around the El Paso region of Texas. The agricultural Tenuirostritermes and Gnathamitermes termites are representatives of the family Termitidae. While specific termite species of this familyu can be destructive in tropical regions of the earth, agricultural termites are not considered structural pests in Texas, as they consume dead grass and hay. Different termite species have different habits and respond differently to Imperium control strategies. No one control strategy is best for all termites.
Wood is made primarily of cellulose, which few animals are able to break down into usable nutrients. The termite has protozoa and bacteria in its hindgut that digests the cellulose. Without these protozoa, a termite will eventually starve to death.
Termites live in highly organized societies, or colonies, with the individuals differentiaded into three forms, called castes:
- workers (pseudergates)
Each caste is specialized for certain jobs or functions.
Workers are by far the most numerous members in the colony. They are creamy white, wingless, eyeless and soft-bodied, with chewing mouthparts. In primitive families, young nymphs called pseudergates may exist instead of a true worker caste. In either case, this group performs the actual work of the colony:
- building and repair of the nest
- feeding and grooming of other castes
The workers find and eat wood, maintain galleries within the wood and care for the colony's king, queen and soldiers.
Th workers maintain the shelter tubes and close any breaks in the surface of the wood they are infesting. Termites must have this closed system to maintain a certain level of humidity. The tubes also serve as protective barrier against natural enemies, especially ants.
Workers are sometimes mistaken for "white ants." They mature within a few months and may live 2 to 3 years. Large numbers of them can be found in forest logs, wood lying in contact with the soil, or in the lumber of buildings.
1 to 3 percent of a colony's population is the soldiers, which guard the colony against predators, primarily ants. Soldiers have greatly enlarged, dark, reddish-brown heads and sword-like mandibles that operate with scissors-like action to attack enemies. Soldiers also mature within a few months and may live 2 to 3 years. They are believed to be sterile, and thus do not participate in reproduction.
There are three types of reproductive termites: primary, secondary and tertiary. The primary reproductives are a winged form (alate) from which a king and queen develop. These winged reproductives are produced in large numbers seasonally. They leave the colony in a swarming flight, shed their wings, and pair off to seek nesting sites where they mate and start new colonies. A queen may lay more than 60,000 eggs during her lifetime.
The primary reproductives are produced in mature colonies (3 to 5 years old or older). They have dark-colored, flattened bodies and large eyes. Their two pairs of wings are qual in length and narrow. After a single, short colonizing flight, the wings break off near the base.
Secondary reproductives, both male and female, develop under certain conditions, such as when the king and queen die or when part of the colony becomes separated from the main colony. These reproductive are wingless but have wing pads (brachypterous). Female secondary reproductives supplement the egg production of the primary queen.
Tertiary reproductives are wingless, with no wing pads (apterous). In absence of primary or secondary reproductives, tertiary reproductives will mate and lay eggs.
Swarms are a dispersal flight that contains both male and female reproductives. As the termites fall to the ground after a short, fluttering flight, a their wings break off. Males and females pair off and begin excavating a new nest. Many termites in a swarm never find a mate or a "homesite,." Others are eaten by predators such as birds and lizards.
Once a pair finds a site and seals themselves in, they will mate, and the female (queen) will begin egg laying. The first batch will be small, usually 6 to 12 eggs. Once these nymphs hatch they begin to eat cellulose and enlarge the colony area. With a larger number of nymphs and pseudergates, the queen will lay increasingly larger numbers of eggs. Reproductive forms usually will not be produced in the first year. It usually takes 2 to 3 years for a newly established colony to begin doing serious damage to structural wood. As the colony grows the secondary reproductives also begin to lay eggs to supplement those laid by the queen. There is not just one central nest containing one queen. Secondary reproductives may be found throughout the colony.
Another way colonies may be formed is by "budding" from a well established colony. Budding occurs when a number of individuals, including one or more secondary reporductives, leave the colony and start a new one.
Stone or concrete building foundations are temporary obstacles to termites. If a crack 1/32 inch wide-develops in these foundations, termites can enter and move into the wood above unless there is some other barrier. Remember, if distances are short, termites can build shelter tubes across foundations to reach wood. So cracks in concrete, continuous openings in building blocks utility openings, expansion joints, and wood below soil level offer the best and easiest access for termites.
IMPERIUM'S IDENTIFICATION AND DETECTION
It is the primary reproductive termite form that are most often discovered by the homeowners. Many people confuse this winged form with flying ants, which can also be found swarming near structures. Termites can be distinguished from ants by comparing their physical characteristics. Winged termites (alates) have straight antennae, thick waists, and four long, fragile, wings of equal size and shape. Winged ants have a wasp-like body shape, narrow waste, and two forewings that are larger than the two rear wings.
Termites usually come to the attention of Imperium in the spring when the winged reproductives swarm. Although a termite swarm out-of-doors near a structure does not necessarily mean your structure is infested, it is a good reason for us to investigate further. If the swarmers emerge inside the structure, they will be attracted to light and their broken-off wings may be found near windows and doors.
When looking for signs of termite activity, Imperium myst also alert for those conditions that favor termite infestations. The most critical condition is wood-to-soil contact. The US Forest Service has identified 15 conditions that frequently lead to termite infestation.
- Cracks in concrete foundations and open voids in concrete foundations are hidden avenues of entry.
- Any wooden posts or supports set in concrete may be in contact with the soil underneath
- Concerete porches with earth fill may provide wood-to-soil contact.
- Form boards left in place contribute to the termite food supply.
- Leaking pipes and dripping faucest in the crawl space keep the soil under the structure moist.
- Blocking crawl space vents with shrubbery will cause the air under the structure to remain damp and warm.
- Construction debris in the backfill beside the structure will contribute to the termites' food supply.
- Low foundation walls and footings will provide wood-to-soil contact.
- Stucco or brick veneer carried down over the concrete foundation allows for hiddden access to the structure.
- Soil-filled planters built up against the side of the structure allow direct access into foundation cracks.
- Form left in slabs, where plumbing drains enter the structure, provide access.
- Wooden porch steps in contact with the soil are entry points.
- Heating units in crawl spaces maintain warm soil temperatures for termite colonies year-round.
- Paper is a wood product. Paper collars around pipes and ducts also provide access to the structure.
- Wooden fences, trellises and other wooden adornments up against the side of the structure may provide access.
Also, any subslab ductwork, for venting a heating unit or "Jenn-Air" type cook-top range, can develop cracks that allow termites to enter below grade. If any of these conditions exist they should be carefully inspected and, if possible, corrected.
Damaged wood often is not noticed unless the exterior surface is removed. However, galleries can be detected by Imperium by tapping the wood every few inches with a screwdriver. Damage wood will sound hollow and the screwdriver may even break through into the galleries. These galleries will contain soil and fecal particles.
Termites can detect vibrations through their legs. They are unable to hear noises near their nests, but are immediately alerted when their nest is tapped. When alarmed, the soldier termites butt their heads agains the gallery walls to initiate the vibrations that will warn the colony. Under certain circumstances it is possible to hear this "ticking" sound
Other signs of infestation are the presence of flattened, earthen shelter tubes that the termites build over the surface of the foundation to reach the wood. These tubes are usually 1/4 to 1/2 inch wide. Termites perish rapidly under dry conditions, so they build these mud tubes to maintain correct humidity throughout the colony. Buildings should be inspected at least once a year for evidence of tubes. In concrete slab construction, Imperium will examine the expansion joints and cracks where pipes and ducts go through the slab. Particular attention must be given by Imperium to bath plumbing traps and exposed soil beneath heating and air conditioning systems.
Termite colonies can develop in wood debris and soil and then enter a building, particularly at cold joints between two pieces of concrete, such as patios or porches.