Landscape mulch, including mulches not made from wood, can attract subterranean termites to a home, but not always. Although wood, paper or straw mulch can be a source of food for termites, the main attraction of mulch is that it makes moist areas easy for making termite tunnels. There are many preventive steps a homeowner can take to use landscape mulch and be sure that their homes are termite free.
Significance of Moisture
Why is moisture so important to termites? Subterranean termites need to stay in moist environments or they die. Their bodies are very soft in comparison to the hard bodies of beetles. If they are exposed to sunlight and heat over an extended period of time, their bodies dry out and die.
Mississippi State University recommends that no matter what type of mulch is used, make piles of two inches or less. This makes tunneling too shallow for termites or can make a couple of tunnels collapse and expose the termites to the sun.
Prevention Tips
Landscape mulch, soil, weeds, shrubs or plants touching the home can look attractive but can attract termites into that home. Always be sure landscape mulch does not touch the sides of a home. Keep mulch and plants at least three feet away from the sides of the home. Instead of using soil or mulch around the sides of the home, use bricks, concrete or large stones as a barrier against tunneling termites. Gravel or plastic mulch may not work depending on how much rainfall your town gets, because these types of mulches can hold in moisture.
Another advantage of not having plants right up against the house is that it makes the edges of the house much easier to check for signs of any insect infestation, according to North Carolina State University. Be sure to fix cracks, even if the wall is made of cement. Subterranean termites have been known to get inside of houses on concrete slabs or with concrete walls due to cracks.
Misconception
Even if your home has been recently treated for termites, termites can still enter your home using landscape mulch or soil as a bridge. Many types of termite extermination places a protective barrier underneath the soil around the house. But if a gardener places a thick, moist pile of mulch on top of this barrier, there will be enough room for the termites to travel from the garden to the home and not be affected by the underground pesticide barrier.
References
North Carolina State University. “Termite Prevention.” http://www.ces.ncsu.edu/depts/ent/notes/Urban/termites/prevent.htm
Texas A & M University System. “Subterranean Termites.” http://insects.tamu.edu/extension/bulletins/b-6080.html
Ohio State University. “Fact Sheet: Termites: How to Reduce Your Home’s Risk of Infestation.” http://ohioline.osu.edu/hyg-fact/2000/2092C.html
YouTube. “Mississippi State University: Mulch and Termites.” http://www.youtube.com/watch?v=cydLVWwhrVA