Termite subterranean, drywood, and dampwood species. Dampwood termites derive their name from the fact that they live in moist wood, especially in stumps and fallen trees in forests. Drywood termites are common and can survive in very dry conditions, even in dead wood in deserts and do not require much moisture or contact with soil. Dampwood termites, feeding by drywood termites can cut across the grain of wood leaving a characteristic pattern of chambers and tunnels, some of which are filled with fecal pellets. Drywood termites often expel their fecal pellets through surface openings and they can accumulate on horizontal surfaces below the openings. These fecal pellets, which are distinctive in appearance with six longitudinal flattened sides, may be the first clue to their presence. structural lumber, dead limbs on trees, utility poles, decks, fences, lumber in storage, and furniture. From this infested wood, winged reproductives periodically swarm to infest additional nearby wood. Drywood termites are most prevalent in southern , including the desert areas, but also occur along most coastal regions and in the Eastern Washington. Nests of most species remain entirely above ground and do not connect to the soil. subterranean termites, Reticulitermes, can be encountered in nearly all regions of the state, from the sand dunes of the coast to the upper elevations of the mountain ranges and even in some of the desert areas. The species of Reticulitermes are the most destructive termites found in Washington. They are small in size compared to dampwood and drywood termites, but mature colonies can contain hundreds of thousands of individuals.
Reproductive winged forms of subterranean termites are dark brown to brownish-black with brownish-gray wings. On warm, sunny days following fall or spring rains, swarms of reproductives may be seen emerging en masse from their underground nests. Soldiers are wingless with light caramel-colored bodies and long, narrow amber-colored heads with no eyes. Workers are slightly smaller than reproductives, wingless, and have a shorter head than soldiers; their color is similar to that of soldiers.Termite colonies are self-perpetuating. When the colony is composed of a large number of individuals, often thousands, a small percentage of individuals develop into winged reproductives (alates or swarmers) that then leave the nest, flying in swarms to mate, disperse, and establish new colonies. Most of these reproductives perish during the flight due to predation by birds, lizards, ants, or other insects. The time of day and year when flights occur varies with species and geographic location. Reticulitermes species swarms during the afternoon in either spring or fall on clear days after a soaking rain. Heterotermes aureus flies in the late afternoon or early evening in July, August, and September. Coptotermes formosanus, although rare in California, flies in the late evening and is attracted to lights. In buildings with heated basements, termites occasionally fly inside during winter.It is unlikely that homeowners will be able to execute subterranean termite control on their own. However, it is important for homeowners to have some familiarity with inspection procedures, reduction of conducive conditions, and treatment strategies. Successful termite management requires special skills and knowledge, including a working knowledge of building construction. An understanding of termite biology and identification can help a homeowner understand and select a suitable method of control. Of course, homeowners can replace termite damaged wood and correct conditions conducive to subterranean termite infestation on their own; however, applications of registered pesticides are highly regulated and require a licensed pest control professional to carry out the inspection and control program.
Multiple colonies of the same termite species or several different species can infest a building. A Extermination inspection and an integrated approach to control are required. A combination of methods, such as habitat modification, elimination of excess moisture, removal of infested wood from the structure, exclusion of termites from the building by physical and/or chemical means, and the use of chemical methods to destroy existing colonies will probably be necessary.
Inspection
An inspection by a licensed pest management professional is required before any treatments can be performed. Most homeowners will be unaware that a subterranean termite problem exists until a significant finding occurs. For instance, an infestation is discovered during an inspection in a real estate transaction, damaged wood is uncovered during a room remodel, a shelter tube appears on an interior or exterior wall, or the sudden appearance of thousands of flying insects in a bathroom or kitchen. These situations are not unusual due to the cryptic and secretive life habits of subterranean termites hidden behind walls or buried away in crawlspaces and under slab foundations.
This Pest Note and other resources found on the Internet show photos and images of termites, shelter tubes, and damage that homeowners can reference if they suspect an infestation or if they want more details about the termite inspection process before contacting a pest control professional. However, because the telltale signs of subterranean termites often occur in dark and sometime hazardous locations (attics or tight crawlspaces that have nails, dust, or standing water), it is recommended that you contact a licensed professional for inspection and subsequent treatment.
Spring time, especially a warm, sunny day following rain, is the optimal time for subterranean termite swarming behavior and, at least for brief moments during the day, a chance to see live termites and perhaps a specific location where they are emerging from in the home. Since most soil around a home has buried cellulose debris (roots, stumps, or fence posts), finding swarming termites in your yard doesn’t necessarily mean your house has termites.
Homes that have had a history of subterranean termite problems can be especially vulnerable to re-infestation and should be inspected by a professional every several years. Washington, like most states, has nonprofit associations that provide contact information for reputable pest control professionals in your area.
Building design may contribute to the probability of termite invasion. Identify and correct any structural deficiencies that attract or promote subterranean termite infestations. Ideally all sub structural wood beneath the building should be kept at least 12 inches above the soil. Consult local building codes for exact, minimum distances from wood to soil. Stucco siding that reaches the ground may promote termite infestations since termites might travel between the stucco and the foundation unseen. Keep foundation areas well ventilated and dry. Reduce chances of infestation by removing any wood in contact with the soil. Inspect porches and other structural or foundation wood for signs of termites. Look for tree stumps, stored lumber, untreated fence posts, and buried scrap wood near the structure that may contribute to a termite infestation.
Structural lumber in buildings is usually Douglas-fir, hemlock, or spruce. Of these materials, Douglas-fir is moderately resistant to termites, whereas the other two are not. Lumber used in foundations and other wood in contact with the soil should be chemically treated or naturally resistant to termites and decay to help protect against termite damage in areas where building designs must be altered or concrete cannot be used. When using naturally resistant wood species, we recommend that you request documentation from suppliers to authenticate resistance levels stated on labeling. If susceptible wood is used above the treated wood, however, subterranean termites can build their shelter tubes over chemically treated wood and infest untreated wood above.
Use only exterior-grade, pressure-treated lumber for areas that are exposed to weather; otherwise, the chemical in the lumber may leach from the wood. All topical treatments that will be exposed to weather must also have a sealer coat to prevent leaching into the soil following rain.
Subterranean termites in structures cannot be controlled using techniques that are appropriate for drywood termites, such as fumigation, heat treatment, freezing, and termite electrocution devices, because the reproductives and a large majority of the termites are concentrated in nests near or below ground level out of reach of these control methods. The primary methods of controlling these termites are insecticides, either applied to the soil adjacent to the structure, directly to nests via shelter tubes, or through bait stations. To facilitate control of subterranean termites, destroy their shelter tubes whenever possible to interrupt access to wooden substructures.
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