Part 2 of our four-part series on termites answers questions about termite structural damage in Arizona by Dr. Robert Smith, Department of Entomology, University of Arizona.

Question: Are termites a serious problem in Arizona?

Answer: Absolutely. We have at least five species that can cause considerable damage to the wooden parts of structures.

Question: Will my house fall down if it is infested with termites?

Answer: No! Even structures heavily infested with termites do not "fall down." That is to say there is almost never a threat of structural damage so extensive the integrity of the whole structure is endangered. Termites seem to be pretty good structural engineers - they almost always leave enough wood to support the structure.

Question: What is the worst thing that can happen in a termite infested house?

Answer: Wallboard may sag from walls and/or ceiling, mud tubes may appear on walls or descending from the ceiling or from wooden cabinetry, wooden trim around doors or windows may become damaged to the extent that they require replacement and occasionally some relatively small area of a wooden structure may give way under unusual load. Selected floor joists or rafters may require reinforcement or replacement.

Question: How is extensive termite damage usually discovered?

Answer: The true extent of termite damage in a structure is most often revealed during major remodeling or exploratory demolition (e.g. drywall removal).

Question: Can I just ignore a termite infestation in my house?

Answer: No! Termite infestations should never be ignored. However, termites work slowly and you have plenty of time to make informed control decisions by seeking several professional opinions and getting proposals from several pest control companies.

Question: What are "pin holes" in dry wall?

Answer: These are tiny holes surrounded by a small amount of mud or discoloration produced by subterranean termites usually in newly infested structures. Pin holes are evidence of a subterranean infestation and thus of a broken or poorly installed or nonexistent chemical barrier.

Question: What does it mean when termites build suspended tubes from the ceiling of a house?

Answer: Mud tubes coming down from the ceiling are produced only by an extensive infestation of subterranean termites. A ceiling tube means that the subterranean termites have a long route established from the soil through the studs to the rafters of the house. The ceiling tubes represent an attempt by subterranean termites to find a short cut back to the soil and the essential moisture it contains.

Question: Can termites bore through concrete?

Answer: No, but they can get through very narrow cracks (<1/16 in.) in concrete footings and concrete pads, and all concrete construction (even the very best) will have shrinkage and settling cracks that provide routes of entry for termites.

Next month Dr. Smith will answer questions about pest control services in Arizona.