Drywood Termites: Facts, Identification & Control
Cryptotermes spp. and Incisitermes spp.
There are three distinct groups into which termites are divided: subterranean, drywood, and dampwood. Since the worker termites in these groups more or less look the same, the appearance of the reproductive caste (alates) and soldiers is important.
Alates, or swarmers, have two sets of wings. The front set of wings has a pattern of three or more heavy, well-pigmented veins in the outer part of that front wing. Also, swarmers shed their wings very quickly after swarming, so most all dead swarmer bodies do not have attached wings. This is a good characteristic to distinguish drywood termite swarms from subterranean termite swarms since subterranean swarmers will consist of dead swarmers with and without attached wings. Swarmers can be up to 12 mm long.
Drywood termite soldiers have large mandibles (mouthparts) with teeth and their pronotum is as wide, or wider, than the head. Also, most drywood termite soldiers and workers are larger than the soldiers and workers in subterranean termite colonies.
Create colonies in wood, with no connection to the ground necessary; often found in attic wood; need very little moisture.
Behavior, Diet & Habits
Wood and occasionally other cellulose material.
Nymphs pass through four to seven instars before reaching adulthood; sexual forms eventually swarm to form new colonies.
Signs of a Drywood Termite Infestation
When a drywood termite colony is mature, swarms of winged male and female reproductive insects are produced. These reproductive termites fly out of their colony to create new colonies after mating. Warm temperatures and heavy rains instigate swarms.
Drywood termites extract as much water as possible from the feces to conserve it. The result are very distinct fecal pellets called frass. They are a hexagonal and all are a similar size of 1 mm long. The termites kick them out of their tunnel. Appearance of mounds of these pellets indicate activity. It is important to note that pellets can remain almost indefinitely from a dead colony and may mislead a homeowner that it is current activity. Contact a termite control professional to confirm current activity.
It is estimated that termites cause over a billion dollars in damage to United States homes each year. Unlike fires, hurricanes and tornadoes, termite damage is seldom covered in homeowner insurance policies. The dangers of termite infestation are also underpublicized, leading most homeowners to believe that no preventive measures are necessary.
However, annual inspections are an effective means of preventing major damage to your home. There are two major families of termite present in North America: subterranean and drywood termites. Both species feed on cellulose material, including books, dried plants and furniture, as well structural wood. While subterranean termites burrow underground, drywood termites do not need the soil. After a colony of drywood termites has gained entrance to a home, they are capable of dispersing widely throughout many rooms and floors.
Although drywood termites are far less common than subterranean termites and are found primarily in coastal, southern states and the Southwestern states, drywood termite damage is substantial. Drywood termite infestations are identifiable by piles of fecal pellets. These fecal pellets are often first noticed in places like windowsills. If you find piles of tiny pellets in your home, it could be a sign of a drywood termite infestation. A trained pest control professional can provide a thorough inspection.