Subterranean Termites
Abstract Soil insecticide barriers have been the single most important tool for subterranean termite control in the last half century, but limitations with current soil termiticides have provided the impetus to look for alternatives in recent years. One such alternative is the monitoring--baiting programme. Monitoring stations to detect termites are placed in the soil surrounding a structure. Once termites are found in the stations, monitoring devices are replaced with slow-acting baits such as the chitin synthesis inhibitor, hexaflumuron. Field studies have indicated that termite colonies were eliminated using less than 1 g of hexaflumuron. After the elimination, monitoring resumes and bait is applied if new termite activity is detected. The monitoring and baiting procedure form the basis for an ongoing programme to protect structures from subterranean termite infestation. Although the cost--benefit model developed for agricultural integrated pest management cannot be applied directly to termite control, the underlying concept for using a cost-effective approach remains the same. The benefits of the monitoring--baiting programme over conventional soil treatment are a reduction in pesticide applied per unit and the elimination of termite populations near structures, resulting in the reduction of liability and damage potential. It is expected that the data management system when used in conjunction with the monitoring--baiting programme will provide a database to improve its cost-effectiveness continuously. Isoptera - subterranean termite control - monitoring--baiting programme

The efficacy of three chitin synthesis inhibitors, diflubenzuron, hexaflumuron, and chlorfluazuron, incorporated into a novel bait matrix to kill the Formosan subterranean termite, Coptotermes formosanus Shiraki, was evaluated in the laboratory. The bait matrix was significantly preferred by C. formosanus over southern yellow pine wood in a two-choice feeding test. Bait formulations containing 250 ppm of the three chitin synthesis inhibitors were presented to termite nests with 2,500 individuals (80% workers and 20% soldiers) in the presence of alternative food sources consisting of cardboard and southern yellow pine, Pinus taeda L., wood. None of the bait formulations were significantly repellent or feeding deterrent to the termite workers evidenced by the lack of full consumption of alternative food sources. All nests presented with the bait formulations died within 9 wk, whereas the control nests (bait with no chitin synthesis inhibitors) remained alive 6 mo after the end of the study. No significant differences in consumption were observed among the chitin synthesis inhibitor treatments. Importance of this study for the improvement of current bait technology is discussed.

Keywords: subterranean termite, bait, chitin synthesis inhibitors, control

1. What kinds of wood are termites most attracted to?
Termites are indiscriminate, and will eat anything with cellulose such as trees and shrubs. Ideally, termites prefer decaying, easy-to-digest food sources like paper or cardboard. However, if the food sources are hard to find, they can eat almost anything. Some species of termites have even been known to chew through plastic or lead to reach a food source!
2. Which plants in the landscape most attract termites?
Termites can infest and destroy anything with cellulose including live trees and shrubs including any woody ornamental. There are some species which are less accepted (e.g., redwood, cedar), but termites have been known to feed on any wood under the right conditions.
3. What are your planting and pruning tips for preventing termites from entering the house via shrubs? How many feet from the house should hedges and shrubs be planted?
Homeowners should trim shrubs enough to allow airflow between the house and shrubs – approximately three to six inches. They should also make sure vinyl siding, wood clapboards, stucco or similar exterior finishes is at least four to six inches from the ground. Their minimum clearance provides an “inspection strip” where the homeowner or their pest management professional can monitor for the presence of mud tubes, which are kind of like a termite highway extending from the ground over exposed surfaces of a house. Any wood coming in contact with the home becomes a likely target. Termites eat wood and keep foraging until they come into contact with something they do not like.
4. Are gardens subject to termite infestation?
Termites can infest and destroy anything with cellulose. Rotting tree stumps or firewood, wooden fence posts, landscape timbers (especially railroad ties which are the main dispersal mechanism for the highly destructive Formosan subterranean termite out of the deep south, where it has become established) are commonly attacked by termites. Termites can easily travel through moist soil, as found in gardens and flowerbeds. Homeowners should also avoid deep (great than 3”) wood mulch next to the foundation of their homes. Materials like pea gravel or stone offer a better alternative and are much less attractive to termites.
5. Are termites attracted to live wood or only dead?
Termites thrive on anything with cellulose including live and dead wood; in living trees, termites are preferentially attacking the heartwood but in the process of the excavations will damage the sapwood. Even new homes are attractive targets. Decaying wood (such as tree stumps, firewood and the timbers of any home) is easy for termites to consume. Termites can feed on homes for up to 10 or 12 years before they become visible to a homeowner. Colder weather only makes termites burrow deeper into the warmth of your home. Scheduling an annual termite inspection is the most effective method for preventing termites and sparing homeowners of costly repair bills.
6. What are the environmental implications of Premise®? Will organic gardeners be offended by our suggestion of this product?
Imidacloprid, the active ingredient in Premise, has to be one of the most thoroughly researched and reviewed insecticides in recent history. It is registered for agricultural, horticultural and non-crop uses in 120 countries. In fact, chances are very good you may already be using one or more of our popular lawn and garden pest control products that contain imidacloprid – like Merit or one of our Bayer Advanced brands. Among termite control options available today, imidacloprid has a very favorable environmental safety profile, but we would encourage readers who have more specific questions to ask their pest management professional or contact Bayer directly by calling (800) 331-2867.
7. Are there any organic alternatives for termite prevention or extermination?
Because termites can cause such large-scale damage, experts recommend a professional treatment. Non-repellent products, like Premise, are the most effective methods to eliminate existing infestations and keep a home free of termites. However, before termites attack, there are a number of things homeowners can do to reduce the risk of termite infestations: