Gravel mulch and subterranean termites

Asked July 27, 2015, 9:08 AM EDT

Good morning, I read the article that appeared in the 7/25-26 weekend edition of the Balt Sun entitled "Using gravel mulch can contribute to root rot" and have a question. The last sentence in the first section of the article indicated that using gravel mulch near foundations may provide an attractive environment for subterranean termites. I was recently advised by a termite/pest control company to specifically clear the organic mulch away for the first 12 inches out from the foundation and replace it with stone. The two recommendations seem to conflict. I'm not understanding how the use of gravel mulch attracts termites? Thanks very much for any insight you can provide.

Howard County Maryland

1 Response

Two possibilities for the confusion:

Termites cannot live in organic mulch, as many people fear.

Also, any mulch will keep the soil somewhat moist (by shading the soil and preventing evaporation), and moist soil attracts termites. That may be why your pest control company advised to keep mulch away from the foundation. However, although it is not intuitive, research shows that stone/gravel mulch actually keeps the soil more moist than organic mulch does. Therefore, the soil under gravel mulch is more attractive to the termites. This fact is not generally known and, since stones seem dry, it seems logical that they would keep the soil more dry--but they do not.

ECN