Subterranean Termites

What do subterranean termites look like?

  • Worker termites (making up the majority of colony members) are milky-white to off-white in color; winged reproductives are dark brown to almost black with brownish-grey wings; soldiers have white bodies and yellow-brown heads—all are about 3/8 inch long.
  • Reproductive wings have a few hairs and two dark veins on the leading edge.
  • Soldiers have rectangular heads which are two times longer than their width and large mandibles which lack teeth.

What are the habits of subterranean termites?  

  • Eastern subterranean termites are found from Ontario southward and from the eastern United States seaboard as far west as Mexico, Arizona, and Utah. Western subterranean termites are found along the Pacific Coast to western Mexico and east into Idaho and Nevada.
  • In Florida, subterranean termites are extremely prevalent and concerning. 
  • Subterranean termite colonies are commonly located in the soil from which the workers build mud tubes to structural wood where they then feed.
  • Subterranean termite colonies are always connected to the soil and/or close to a moisture source (without this connection, colony life is usually not sustainable). 
  • A mature queen produces 5,000 to 10,000 eggs per year.
  • Average colonies consist of 60,000 to 250,000 members; however, colonies numbering in the millions are possible.
  • Queens live for up to 30 years and workers as long as five years.
  • Winged reproductive serves the function of establishing new suitable colonies and typically emerge in the spring and commonly after a warm rain. 

What kind of damage can occur from subterranean termite infestations?

  • An average colony consumes up to 3 linear feet of pine studs within one year.
  • Within three months, subs can cause extensive damage to wood within structures and in a span of years, major structural damage can occur.  
  • Subterranean termites are the second most destructive termite species to infest structures within the United States.

What should I look for? 

  • Look for small 1/16” pinholes in vertical or horizontal drywall (that may be a result of feeding on studs or timber members behind the drywall). 
  • Look for small dabs of mud on drywall, baseboard moldings, around the framing of doors over raised stoops, around window frames, or front/back walls of brick row-houses.
  • On the exterior, look at the underside of downspout pavers, stepping stones, under wood piles, old tree stumps.
  • Look for the presence of swarmers or large collections of wings—found without explanation.  
  • Look for mud tubes or “drop” tubes that may be suspended from wood joists. 

How do I control and kill subterranean termites? 

  • Moisture conditions that knowingly exist in/around structures or homes should be corrected.  
  • Downspouts should have drainage assemblies that divert water away from structures. 
  • Scrap wood, firewood, and other wood in contact with the soil should be removed.
  • At least six inches between wood and/or foam insulation and exterior soil grade should be maintained.
  • At least 18 inches between the soil in a crawl space and the floor joists should be maintained.
  • Water leaks and situations in which there is more than 15% wood moisture content must be repaired.
  • Drainage around the structure should be designed so that there is no accumulation of water near the foundation. Particular attention should be paid to situations that might contribute to this condition, e.g., poor exterior soil grades, planter boxes, sprinkler systems, air conditioner condensate drains, lack of gutters, gutter down spouts, etc.
  • A number of strategies are available to control subterranean termites that require the services of a pest control company. They include spot-treatment, barrier insecticide treatments, and baiting.
  • Termidor termiticide is highly recommended due to its 99% efficacy over a 10-year period of time and non-repellant characteristics.  

Note: Treatment for Subterranean termites should be performed only by licensed professional pest control operators such as the Innotech Pest Management team of entomologist-led technicians.