Every year, roughly 600,000 homes in the US are affected by termites. Overall, experts estimate the annual cost of termite damage and control to be over $5 billion.
Except for Alaska, termites can be found in every US state. Generally, the incidence of termite infestation is higher in southeastern states, such as Florida, and west coast states, such as California. The more northerly states have a lower incidence of attacks.
Of the approximately 50 species of termite found in the US, only 20 are classified as pests.
Termite colonies can vary in size and structure depending on the species. Colonies can range in size from only a few hundred insects to giant nests consisting of millions of individuals.
Termites are social insects, with a highly developed caste system. Different members develop in specific ways to fulfill certain functions. The colony will normally contain queens and kings, along with large numbers of infertile workers and soldiers.
Although infertile, workers may be male or female and are responsible for the labor in the colony. Their work includes foraging for food, nest maintenance and caring for the nymphs.
Soldiers have larger heads and jaws than other termites, which they use to protect the colony from attack, often by ants. Soldiers also have a role in organizing the workers.
At certain points in the life of the colony fertile winged adults, called alates, are produced that disperse to start new colonies. Due to the large number of alates that appear at these times, they are often called swarmers.
Termite queens are the longest-lived of all insects, often living 20 or more years. In a well-established colony, a mature queen can lay 40,000 eggs in a single day.
Unlike many insects, termites undergo an incomplete metamorphosis. The eggs hatch into nymphs, which after several molts become adults. The number of these molts varies by species and is determined by the role of the termite in the colony.
For the first few molts, all termites look similar. Depending on what functions are needed, the queen will produce pheromones to dictate how a termite continues its development. Most termites become workers.
The time taken to complete a termite’s lifecycle varies depending on the availability of food, temperature and the needs of the colony.
Termites primarily eat cellulose. Their main source of cellulose is grass, wood, rotten trees and dead leaves.
Unfortunately, many homes and furnishings also contain cellulose, which makes them targets for termites. Protein and carbohydrate are also required, which they get from fungi in rotting plant material.
Only workers and older nymphs can turn cellulose into digestible food. The protozoa and bacteria present in their gut are able to break it down. The workers then feed the rest of the colony using a food sharing process called trophallaxis to pass on the digested cellulose to other termites.
Identifying individual species can be very difficult. To overcome this, termites are grouped into three categories: subterranean, drywood, and dampwood.
Even within the categories, workers and nymphs are so alike in different species that it is hard to separate them. Pest control professionals normally identify a species by its soldiers or alates.
Subterranean termites cause the most damage to homes in the US and can be found in all states except Alaska.
According to the USDA, Formosan termites alone are responsible for causing $1 billion of damage a year. This species is found along the Gulf coast primarily in Louisiana, Mississippi.
Subterranean termites are ground dwelling insects. They obtain the moisture they need from the soil. The colonies can be very large and are often located away from a home under attack, connected to it by underground tunnels. If there is an underground barrier, the termites may use mud-walled galleries to travel above ground.
Unlike other termites, subterranean ones tend to prefer soft wood and eat along the grain. This causes the common ‘layered’ look often seen in termite attacks.
Drywood termites don’t need contact with soil to survive and can thrive in areas with a low moisture content. They get needed water from the wood they feed on. Although their colonies are often relatively small, they can cause significant damage to homes if left untreated. Infestations normally develop at a relatively slow rate.