Subterranean termites are termites whose mode of nesting is within soil. Termites have several modes of nesting, and soil nesting is the most common mode of nesting for many species. The other modes of nesting are arboreal nesting, mound nesting, and wood nesting. Soil nesting has many advantages for termites, and some species (typically from the Rhinotermitidae family) can be very adaptable in cohabiting with humans in human modified environments, like in urban and semi urban areas. This adaptability also puts them in conflict with humans.
Not all subterranean termites are destructive pests. The most destructive types are those that can thrive in urban areas, build large colonies, and their nests being deep underground, can’t be seen and are hard to detect. From their underground nests, tunnels radiate out in all directions, through which these subterranean termites forage for sources of wood. Many subterranean termites are pale or whitish in color (perhaps an adaptation for living underground with no light); hence are often called white ants.
In rainforests in tropical regions, subterranean dwelling termites are very abundant; any spadeful of earth inside a rainforest will yield a lot of termites from a diverse range of species (most of them subterranean in nesting habit). These termites being among the most significant decomposers of plant and wood matter, within these ecosystems.
Coptotermes spp comprise a large majority of the incidences of subterranean termites damaging buildings in Asia and Australasia (Schedorhinotermes spp and others have also been reported, although on a much smaller scale); while in the US, Canada and southern Europe, the majority of building damage is by Reticulitermes spp, which is rather similar to Coptotermes in many respects. South America is slightly different – Nasutitermes spp are also commonly reported as pests.
The most well known subterranean termite today is (probably) the Formosan Subterranean Termite (Coptotermes formosanus), that has gained an unenviable reputation in many countries due to migration.
Many species of the Coptotermitinae subfamily are frequently called “Formosan termites” collectively, by virtue of most of them having a very similar appearance to C. formosanus, or rather, to each other. They are easily recognizable in general - The soldiers can generally be described as having an ovoid, orange head and a white body, while the workers are almost all white.
A peek inside part of a nest of subterranean termites
Many species of Coptotermes are pests of either dead or living wood. Their ability to thrive in urban areas and consume almost all types of wood while developing huge colonies, gives them an edge over all the other species of subterranean termites. Due to a lack of competition by other species, Coptotermes spp are able to easily establish themselves in urban areas. In semi urban areas, other types of subterranean termites may move in to infest buildings, especially semi derelict or poorly maintained buildings.
Reticulitermes are another prominent genus, courtesy of being the most common subterranean termite type in North America, and in regions of southern Europe. Reticulitermes flavipes (also called the Eastern Subterranean Termite) seems to be the most well known and widely distributed species in North America. The soldiers can be differentiated from Coptotermes by virtue of having a longer, more rectangular head, thicker set of mandibles, and a more yellowish body.
A common trait of subterranean termites is their habit of building shelter tubes when they have to venture over exposed areas. These "mud tubes" are noticeable in heavy infestations. They allow the termites to cross exposed surfaces without getting seen, as well as protect them from dessication. Their underground habits mean that many species have evolved a pale color, often leading people to refer to them as "white ants." There are also many subterranean termite species that do not build shelter tubes (especially forest dwelling species); but the habit of building shelter tubes seems characteristic of those destructive species' that co-exist with humans.
Frequently damaged parts of a building
Generally, the most frequently damaged parts of a building (if attacked by subterranean termites) include parts like door and window frames, wooden skirts, wooden floors, wall paneling, and wooden furnishings like cabinets and cupboards that are located close to, or touching a wall. In heavy infestations, subterranean termites can and will attack wooden roofing, as well as paper and cardboard stacks (books and boxes), and sometimes bite through wiring in the wall.
How do subterranean termites get into a house?
There are some areas of a house or building where subterranean termites frequently use to gain entry; these are for example:
- Along electrical conduits built into the wall
- Along water pipes, especially those built into walls
- Bases of doorframes
- Crevices and gaps in wall and foundation masonry
You will notice that almost all termite control methods are targeted at subterranean termites, such as termite barriers and termite baiting systems, because 1) they are usually the ones attacking buildings 2) their nests are not easy to locate, thus making any elimination of their colonies hard. Subterranean nesting termites have become such successful pests because often, they are the only ones that can succeed in colonizing an urban environment at the expense of other kinds of termites.