   Watch for Termites - April 17, 2013 Jeff Schalau, Agent, Agriculture & Natural Resources University of Arizona Cooperative Extension, Yavapai County Termites belong to the order Isoptera (iso-ptera = equal-winged), which refers to the adults which have two pairs of equal length wings. There are 17 species of termites that occur in Arizona, but only 7 species are considered to be economically important pests. Entomologists have placed these species into three broad categories based on their habitat: subterranean, damp-wood, and dry-wood. Ecologically, termites are beneficial in natural environments because they recycle materials and release nutrients which are available to plants. All termites live in social groups with different castes of individuals each having specific job functions in the colony: reproductive adults, soldiers, and workers. Termites undergo gradual metamorphosis (egg – nymph – adult) with each caste looking and behaving differently from other members of the group. Reproductive kings and queens mate to produce new termites. Soldiers defend the colony and workers expand the colony’s foraging territory. Winged adults (also called “alates”) are another caste which disperse from their colony in a series of flights or swarms at precise times of the year to create new colonies. The timing of the flights varies among species, and within species based on locality. Subterranean termites derive their name from the fact that they must be in contact with soil as a source of moisture. For these termites to move into a wood source above ground, they construct “mud” tubes made of soil, soft fecal matter and wood chips. Subterranean termites are the most common termite pest in Arizona and their presence is easily observed. Damp-wood termites are found in sound dead wood that is moist. These termites nest in soil and come to wood for food, but are not considered economic pests. Dry-wood termites are capable of infesting dry wood that is not in contact with the ground. Because they do not construct earthen mud tubes, infestations are more difficult to detect. A sign of dry-wood termite infestation is the presence of hard, dry fecal pellets that resemble fine sawdust. Termites can cause damage to wood and compromise structural integrity. The first step in successful pest management is correct identification of the pest. The next step is to gain and understanding of that particular species’ biology and habitat requirements. In addition, effective termite management can require some knowledge of building construction. For most people, it is advisable to hire a reputable, professional pest control company to carry out your inspection and control program. Prevention is also an important termite management strategy. This can be accomplished through proper building design and using termite resistant construction materials in the appropriate areas. Some recommendations follow.
In the past, chlorinated hydrocarbon insecticides (e.g., chlordane) and organophosphates (chlorpyrifos) were extensively used for termite control but many of these materials have been phased out because of health and environmental concerns. Termiticides currently available are not as persistent, but they are safer for humans, non-target organisms, and the environment. Again, it is recommended that these insecticides be applied by licensed professionals. I have included additional termite identification and management information with the on-line version of this column (see URL below). There, I have also linked a recent Science News article about termites that are conducting rainwater harvesting in the Namib Desert. Follow the Backyard Gardener on Twitter – use the link on the BYG website. If you have other gardening questions, call the Master Gardener help line in the Camp Verde office at 928-554-8999 Ext. 3 or e-mail us at cottonwoodmg@yahoo.com and be sure to include your name, address and phone number. Find past Backyard Gardener columns or provide feedback at the Backyard Gardener web site: http://cals.arizona.edu/yavapai/anr/hort/byg/. Additional Resources Arizona Termites of Economic Importance, University of Arizona Cooperative Extension http://ag.arizona.edu/pubs/insects/az1369.pdf Termites, University of California IPM On-Line http://www.ipm.ucdavis.edu/PMG/PESTNOTES/pn7415.html Termites, Not Fairies, Cause Plant Circles in African Deserts, Science News, March 28, 2013 Click here for pdf.  Natural rings of perennial grasses manage to survive in parched terrain of NamibRand, Namibia, thanks to a termite that creates areas of moisture within the sand. Credit: N. Jürgens  |