Termites and Mulch
This article was originally published on April 2, 2012 and expired on May 15, 2012. It is provided here for archival purposes and may contain dated information.
Every year a common myth emerges claiming that fresh mulch used in home landscape beds could contain termites. Rhonda Ferree, University of Illinois extension educator, horticulture, says not to believe this myth. "Don't worry about what you buy this spring. Bagged wood chips and shredded bark mulch are safe to use."
Mulch that originates in in the South can sometimes contain the Formosan termite, which was imported years ago from China. Ferree says this termite does cause severe devastation to homes in the southern United States. However, the pest doesn't have the ability to survive Illinois winters.
David Robson, Extension Specialist, PSEP, explains further that "Termites can't reproduce and cause massive problems in one year." It's an on-going problem as colonies build up over the years. Since these termites die during the winter, the colony never gets a chance to get established.
In addition, termites feed below ground–they are subterranean creatures. So, they won't be in the materials as they are pulverized into mulch. The biggest problem may occur when the ground-up wood material is allowed to sit on the ground for months. At that point, it may be colonized by the termites. But, the termites probably will be using it more for feeding than for nesting.
"Termites won't likely survive a chipping and bagging process. Termites prefer cool, moist conditions that are seldom found in bagged mulch," says Robson. "And if for some reason the termites did survive the chipping, there is a strong possibility that few termites would be packaged together, also limiting the chance that termites would colonize quickly up north."
Homeowners can limit termite activity, even with the ones present in Illinois, by mulching properly. "Apply no more than 3 inches of mulch to any area," advises Robson. "This allows the mulch to dry out regularly, creating a dry environment that termites dislike. You can even mulch up to the foundation of your home if you limit the depth to less than 3 inches."
Each spring use a rake to move the mulch around. This "fluffing" not only helps improve air circulation, but it also keeps the mulch on the dry side.
Avoid keeping mulch wet. Instead, water plants individually or use a drip irrigation system.
Original Source: David J. Robson, Extension Specialist, PSEP, email@example.com
Source: Rhonda J. Ferree, Extension Educator, Horticulture, firstname.lastname@example.org
Pull date: May 15, 2012