Owing to their wood-eating habits, many termite species can do great damage to unprotected buildings and other wooden structures. Their habit of remaining concealed often results in their presence being undetected until the timbers are severely damaged and exhibit surface changes. Once termites have entered a building, they do not limit themselves to wood; they also damage paper, cloth, carpets, and other cellulosic materials. Particles taken from soft plastics, plaster, rubber, and sealants such as silicone rubber and acrylics are often employed in construction.
Dampwood termites (Termopsidae) constitute a small and rather primitive family of termites (Isoptera). They contain a mere four or five extant genera with 13–20 living species, but can be divided into several subfamilies. They may be a nuisance, but compared to the drywood termites (Kalotermitidae), usually do not cause extensive damage to buildings or other man-made structures. As their name implies, they eat wood that is not dried out, perhaps even rotting, and consequently of little use to humans.
The termites as a group were traditionally placed in the Exopterygota, but such an indiscriminate treatment makes that group a paraphyletic grade of basal neopterans. Thus, the termites and their closest relatives like the cockroaches relatives are now separated in a clade called Dictyoptera. The dampwood termites are sometimes included with the harvester termites (Hodotermitidae), but this is not followed by the majority of authors and indeed the two families seem to represent distinct lineages which both merely retain some similar plesiomorphies and are generally among the more basal Isoptera.
Two of the subfamilies usually placed in the Termopsidae are monotypic. The other one contains three living genera. However, Stolotermes is somewhat aberrant and its placement in the Termopsidae is in need of scrutiny; current understanding suggests it might be better considered much closer to the most advanced termites, such as Rhinotermitidae and Termitidae; perhaps it would better be placed with these, perhaps it even deserves to be treated as a family on its own like Serritermes.
Incisitermes minor is a species of termite in the family Kalotermitidae known commonly as the western drywood termite. It is native to western North America, including the western United States and northern Mexico. It has been found in many other parts of the United States, all the way to the East Coast. It has been reported from Toronto. It has been introduced to Hawaii. It has been noted in China and it is not uncommon in Japan. This is an economically important pest of wooden structures, including houses. In California and Arizona alone its economic impact is estimated to be about $250 million per year
Within a single colony there are three types of termites, the alates, soldier, and worker. This eusocial species is a dark brown color and has an orange head. The colonies are most active during the spring and summer, preferring to be active in higher temperatures.
This species is probably the most destructive of the dryland termite species in the western United States, while rhinotermitidae subterranean termite damage is more costly. The Reticulitermes hesperus|western subterranean termite (Reticulitermes hesperus) is considered to be the worst termite pest in California, with I. minor in second place. This is a picture of what wood looks like after it has been eaten by termites. The inside is full of holes, so the strength is compromised.
In Southern California, it is estimated that this species represents about half of all reports of wood-destroying organisms, and much more closer to the coastline. Urban sprawl will likely increase populations
The Formosan subterranean termite (Coptotermes formosanus) is an invasive species of termite. It has been transported worldwide from its native range in southern China to Formosa (Taiwan, where it gets its name) and Japan. In the 20th century it became established in South Africa, Hawaii and in the continental United States.
The Formosan subterranean termite is often nicknamed the super-termite because of its destructive habits. This is because of the large size of its colonies, and the termites' ability to consume wood at a rapid rate. A single colony may contain several million individuals (compared with several hundred thousand termites for other subterranean termite species) that forage up to 300 feet (100 m) in soil. A mature Formosan colony can consume as much as 13 ounces of wood a day (ca. 400 g) and severely damage a structure in as little as three months. Because of its population size and foraging range, the presence of a colony poses serious threats to nearby structures. Once established, Formosan subterranean termites have never been eradicated from an area.
Formosan subterranean termites infest a wide variety of structures (including boats and high-rise condominiums) and can damage trees. In the United States, along other species, Coptotermes gestroi, also introduced from south east Asia, they are responsible for tremendous damage to property resulting in large treatment and repair costs.
Formosan termites are rarely found north of 35° north latitude. They have been reported from eleven states including: Alabama, California, Florida, Georgia, Hawaii, Louisiana, Mississippi, North Carolina, South Carolina, Tennessee, and Texas. Their distribution will probably continue to be restricted to southern areas of the United States because the eggs will not hatch below about 20°C (68 °F).