Termite control treatment….Management of Subterranean Termites

Subterranean Termites

It is unlikely that homeowners will be able to execute subterranean termite control on their own faut il une ordonnance pour viagra. 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 professional 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.


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 reinfestation and should be inspected by a professional every several years. California, 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 substructural 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.

Replacing Lumber in Structures

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.

Controlling Subterranean Termites

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.


Liquid applications of pesticides are most often used for subterranean termite control and applied to the soil either in drenches or by injection. There are no reliable over-the-counter termite control products available for the public in California; all effective products are for professional use only.

Pest management professionals are provided special training because of the hazards involved in applying insecticides to the soil around and under buildings. Applications in the wrong place can cause insecticide contamination of heating ducts and/or damage to radiant heat pipes or plumbing used for water or sewage under the treated building. Soil type, weather, and application techniques influence the mobility of insecticides in the soil; soil-applied insecticides must not leach through the soil profile to contaminate groundwater or run off to contaminate surface water.

Recently, active ingredients used to control subterranean termites in soils were broadly classified as repellent or nonrepellent. Subterranean termites can detect repellent insecticides, usually pyrethroids; and they are repelled without receiving a dose that would kill them. Because of this negative reaction, termiticide products containing repellent active ingredients have been phased out.

Newly introduced chemicals are available that are less toxic to humans and other mammals than the older insecticides but remain highly toxic to insects. These insecticides, including chlorantraniliprole, fipronil, and imidacloprid are nonrepellent to termites and have been shown to be effective in killing termites at low dosage rates under California’s climatic conditions. Depending on the label language, these materials are used as barriers as described above and also as local treatments, targeting nests directly via shelter tubes.


Subterranean termite baits, which are slow-acting insecticides consumed during feeding and shared within the colony, are commercially available in California. Generally, bait is delivered within a cellulose or wood matrix infused with the active ingredient and installed underground at regular intervals around a structure. Commercial bait products are also available for above-ground use, where there is no soil for in-ground station installation. This method of controlling termites is very appealing because it doesn’t require extensive site preparation, such as trenching, or extensive application of insecticides to the soil or structure, and because the most effective baits use insect growth regulators (IGRs) to suppress or destroy the entire colony. IGRs have very low toxicity to humans and their pets. The most effective bait products, however, are available for professional use only.