Order: Isoptera
Family: Termitidae
CHARACTERISTICS:
Termites belong to the insect order ISOPTERA. Although they are not related to ants, they are often referred to as 'white ants' because they, just as ants, are social insects living in large colonies. A major difference between ants and termites lies in the shape of their bodies. Ants have a constriction half way down their body (like wasps), whereas termites have a uniform broad body without any constrictions. Termites feed on a variety of cellulosecontaining material such as wood, bark, leaves, fungi and grass. Termites harbour one-celled organisms in the digestive tracts, and these organisms convert cellulose into substances the termites can digest.
SPECIES CHARACTERISTICS:
Microtermes
Microtermes is the most common of the small fungus growers. They build subterranean nests with little evidence of their nests above ground. They can destroy timber in- and outdoors.
Macrotermes
Macrotermes is a large fungus grower. They build large mounds of particular forms which can change the appearance of a landscape considerably. These mounds can remain intact long after the original occupants have left, providing shelter for new occupants and provide a habitat for plant-life different than the surrounding vegetation.
Odontotermes
Odontotermes are wood-destroying termites, and together with Macrotermes, destroy more wood in buildings than all the other subterranean termites together. They build subterranean nests and in most species, only either slight amorphous soil elevation is visible above the nest area or chimneys build of clay. They can also build their nests under buildings.
AREAS WHERE FOUND:
These insects are common in soil and play an important role in the environment to help convert dead wood and other organic materials containing cellulose to humus. Subterranean termites need wood for food and soil for moisture. Wood in contact with soil is ideal for termite development, in the case of houses built on concrete slabs, infestation occurs through expansion joints, cracks and utility and plumbing openings.
IMPORTANCE AS A PEST:
Subterranean termites are the most important of the wood-destroying insects and termite management can be a major part of pest control work. Subterranean termites can, become serious pests in buildings and plantations. Subterranean termites in buildings are difficult to detect and it is mostly damage to furniture, skirtings, wooden floors and other wooden structures that reveal the presence of these insects.
Termite workers will, however, remove all palatable wood from the inside of wooden structures, and damage is often only noticed when a structure is hollowed out completely. Subterranean termites can and will destroy unprotected wooden structures and timber if given half a chance. Mud plastered on walls or over impenetrable foundations to provide lines between the nest and food, is also a tell-tale sign of a subterranean termite infestation. Termites are social insects. This means there are divisions of labour among the different types of individuals, called castes. Nearly all termite species have reproductive and soldier castes as well as a distinctive worker caste. Workers and nymphs perform all the work of the colony –and are the forms that do all of the damage. Soldiers serve only to defend the colony, they cannot eat wood.
LIFE-CYCLE:
- SWARMING TO START A NEW COLONY
At certain times of the year, numerous small immature, nymphal termites from mature colonies molt into larger nymphs with wing buds. Sometime later, these individuals molt into sexually mature males and females called swarmers, or alates. Swarmers have two pairs of long narrow wings of equal size, thus describing the name of the order of classification to which termites belong: Isoptera (“iso,” meaning same, and “ptera”, meaning winged). Unlike other termites in the colony swarmers are dark in colour. During the spring and often triggered by a combination of warm temperatures and rain, swarmers, which are both male and female, leave the nest in large numbers by taking flight from specially constructed mud tubes built 2.5 cm above the surface of the substrate in which termites are living and feeding. Termites continue to swarm throughout the summer, although less frequently than during the spring. Colonies normally swarm only once per season but may swarm twice or more; second and later swarms generally do not match the intensity of the first swarm. Some species swarm during the day and others at night. Swarm flights are are brief, and swarmers are not good fliers. Often they are transported by prevailing winds. Typically, they do not fly very far before landing on the ground but, if winds are strong swarmers can be carried great distances. A female (queen) will attract a male (king) with her sex pheromone. As soon a male finds a female, they will break their wings off, mate and build a new colony. The female will increase in size over time and will be referred to as physogastric. She turns into an egg laying machine - in some species a female can produce up to 30 000 eggs a day and rear the first group of workers. Each termite colony is self supportive and essentially independent of other colonies. - COLONY BUDDING
If one or both the primary reproductives die or if part of the colony becomes isolated, then, supplementary reproductives may be produced. Supplementary reproductives help expand the foraging territory of termite colonies, and often aid in the formation of new colonies. As a colony increases in size, groups of foragers may form satellite-like colonies, or areas of concentrated activities. Sterile workers are the workforce of the colony. They are responsible for foraging, caring for the eggs, the nymphs, the queen and the soldiers, as well as for building and repairing the nest. The worker caste is the most numerous caste in the colony, and consists of sterile males and females. Termites are attracted to moisture in the soil and will quickly find any cellulose food sources in contact with the soil. Soldiers protect the colony from any unwelcome visitors. Soldiers can be male and female, only male (Nasutitermitinae) or only females (Macroterminae and Termitinae). The head is structurally changed to provide the soldiers with the necessary weapon of defence. In most species, the head is extremely muscled with enlarged mandibles for fighting. Soldiers of the Nasutiterminae family have a long frontal rostrum through which they can spray a sticky solution. Soldiers of the family Kalotermitidae have strongly sclerotized heads that are used to block the entrance of the nest when necessary. - COLONY STRUCTURE
Termites are social insects that live in colonies. The colony can be viewed as a single living entity whose parts work together toward survival and reproduction and not as a collection of individuals. The colony structure of termites are different to other social insects such as ants and other hymenoptera`s – that is, a single, centralised colony in the soil from which workers forage in search of food and water. It is more likely that subterranean termite social groups are decentralized, and follow a loose pattern in their movement activity. The typical termite colony is thought to forage, or concentrate their activity in different locations at different time via a network of extensive subterranean tunnels. Its members are nearly always on the move. Termite foraging activity might be concentrated in one section of the territory at one point, and just days or weeks later might shift activity to yet another section of the foraging territory. Alternatively, colony members might expand the size of their present foraging territory altogether.
CONTROL:
In the past, chemicals used in subterranean termite control, aimed to form a barrier around buildings to protect these buildings from termite attack. The chemicals were detected and avoided by the termites. The termites would, however, continue to find a way to enter these buildings by continuing to search through an 'opening' in the barrier. The new generation termiticides, cannot be detected by termites and the insects will therefore move through the treated area and get intoxicated. Premise® 200 SC is such a new generation product.
