08 - Conducive Conditions (Common Termite Risk Factors)
In the world of termite management and regulation the phrase “conducive conditions” refers to risk factors that increases the potential for a building to be attacked by termites. Even when buildings have been properly treated for termites, situations can occur that increase the potential for treatment failure. It is important for homeowners and building managers to be aware of conducive conditions and promptly correct them when they occur. Here are some general descriptions of conducive conditions:
- The building is not treated! It is important that all buildings be properly protected with a preventive termite treatment and that any new addition be properly treated.
- Any activity that disturbs the band of treated soil around the outside of a building will increase the risk of attack. This includes any activity that moves treated soil away from the area or any activity that moves soil, mulch, leaf litter, or pine straw over the treated band of soil.
- Direct contact of soil, mulch, or leaves with any wooden part of the house, or with siding or insulation, will provide a ready entry point for termites.
- Excessive water accumulating against the foundation or over the treated soil can leach, break down or wash away termiticide. This includes water from poor drainage, gutter downspouts, air conditioner condensation, leaky faucets, or excessive irrigation.
- Moist wood is a major conducive condition for termite infestations. This is true whether the moisture results from leaks in roofs, flashing around chimneys or skylights, or other structural components; from plumbing leaks or air conditioner condensation drips; or from moisture condensation due to poor ventilation.
Roll over the images and click the right or left arrows.
Trees growing too near a building will force roots beneath the foundation, penetrating soil-applied insecticide barriers and resulting in cracked foundations. Decaying tree roots lead termites into a building.
Any direct wood-to-soil contact within a building’s foundation results in a high risk of termite invasion. This is true even for “treated” wood.
Organic mulch, such as this pine straw, piled against exterior walls greatly increases risks of termite attack, especially if the material is so thick that it reaches the lower level of siding. Degrading mulch allows termites to tunnel directly into the building, bypassing any soil-applied insecticide treatments.
Untreated soil, washed in by rainfall, accumulated against the edge of the slab in this house, eventually reaching the plate (removed) and studs in the screened back porch. Termites invaded this porch at several different points, causing tens of thousands of dollars in damage repair costs.
Maintaining a narrow, mulch-free strip along the foundation of a building helps reduce risks of termite infestation.
Foundation plantings that are too close to the building increase the potential for termite infestation and make inspection more difficult. On the positive side, this building has good spacing between the soil surface and the lower edge of siding.
Adding a room, such as this screened-in porch, and not having it properly pretreated is a common cause of termite infestations.
Storm-damaged flashing on this apartment building allowed water to leak into second story walls, resulting in a heavy Formosan termite infestation.
Splash blocks direct water from gutter downspouts away from building foundations and reduce potential for termite infestation by preventing soil movement and slowing the breakdown of termiticide barriers.
Built-in planters adjacent to building foundations increase the potential for termite infestation, especially if soil is tilled for planting and/or additional soil is added.
Following are some specific examples of conducive conditions for termite infestation.
- The building has never been treated for termites.
- When the building was built, the horizontal pretreatment barrier was applied, but the final exterior perimeter treatment or vertical barrier was never applied.
- The building was treated long ago and the termiticide has degraded and is no longer effective.
- A new room(s) was added to the building but was not treated properly.
- Adding a patio or deck and not having the disturbed soil area retreated.
- Adding a trellis, steps or other wood structure using untreated wood.
- Allowing soil to contact siding or any wooden portion of the building.
- Buildings with foam insulation or stucco that extends below soil grade (ICF, Drivit, etc.).
- Wooden stakes or form boards left in soil after construction.
- Wooden debris buried in dirt-filled porches or other areas after construction.
- Wooden debris or stumps left in crawl space under building.
- Inadequate ventilation under houses with crawl spaces, resulting in moisture problems.
- Digging or tilling in the treated soil band.
- Adding raised flower beds against the outer wall of the building.
- Adding planter boxes with soil on the roof of a building.
- Stacking firewood or lumber against the building.
- Piling mulch against the foundation.
- Allowing leaves or pine straw to accumulate against the building.
- Planting shrubs or flowerbeds too near the foundation, making inspections difficult.
- Trees growing too near the building, where roots can grow under the foundation.
- Soil being washed away from or against the foundation.
- Removing or replacing treated soil when installing plumbing or other utilities.
- Dogs or other animals digging in the treated soil band.
- Water from roof or downspouts dripping onto treated soil band.
- Water from air conditioners or leaky faucets dripping onto treated soil band.
- Excessive irrigation water leaching through treated soil band.
- Poor drainage allowing water to pool against the foundation.
- Moist wood due to plumbing leaks, roof leaks, or condensation.
- Termite bait stations being destroyed by lawn maintenance or other activities.
- Allowing the termite contract to lapse on a building protected by a termite baiting system.
Dr. Blake Layton, Extension Entomology Specialist
Department of Entomology, Mississippi State University
STARKVILLE, Miss. -- The Mississippi State University Extension Service judged that the most economically important insects in the state should have their own website.
The site, https://extension.msstate.edu/termites, is the go-to place for information on termite biology, identification and control. The site describes the different species of termites found in the state and provides answers to common questions about the pests.