Understanding Ants Still The Key To Their Control

In the ongoing struggle to eliminate ants, the pest control operator’s most effective tool is his or her knowledge of thepest, according to Jeffrey Tucker, president, EntomologyAssociates, Houston, Texas. Tucker stressed the importance of being well-versed in ant biology and behavior and offered his insights on the best methods for ant control at the “Ant Management and Survival Course,” sponsored by Whitmire Micro-Gen Research Laboratories, held in Columbus, Ohio, March 9. Ant baits have proven an effective control tool, but only when used correctly and only as part of an overall pest management plan, according to Tucker. He said baits are an excellent control option, but he warns they’re not a “magic bullet.”

Because advancements in baits and baiting technology are help-ing PCOs win on the cockroach control front, many are baiting ants similarly and have been disappointed with the results, according to Tucker. “The primary pest, the one that emerges most frequently in complaint calls or calls for assistance, is ants,” Tucker said. “Ants are very, very different. Controlling ants takes a lot more effort and intelligence than controlling cockroaches. When technicians try to adapt cockroach control techniques to ants they dismally fail. Ants require a specialized style of pest control.”

Unlike cockroaches, which have only a small number of species that commonly infest structures, there are dozens of ant species that invade homes and businesses. That’s why proper identification is so important. What should a PCO examine first when attempting to identify a specimen? Like all insects, ants have three basic body regions — head, thorax and abdomen. The most important identifying characteristic is the pedicel, the narrow segment between the thorax and the abdomen. The pedicel consists of one or two segments that are commonly called nodes. This is the structure PCOs should study first when attempting to identify an ant specimen because ants are divided into one- and two-node species. Another important identifying characteristic is the antenna, particularly the number of segments in the antenna, which is specific to most genera of ants.

Keep in mind, however, that to properly identify ants, one must first have the proper equipment. This includes a good hand lens and vials filled with rubbing alcohol to preserve specimens.

TOOLS OF CONTROL. In many ways, the methods of ant control practiced in the industry’s infancy are the ones being used today, Tucker said. Probably the biggest change in the approach to ant control is the reduction in the use of liquid insecticides. Spraying a large number of visible ants has a minimal effect because only one-fourth of an ant colony forages at any given time. The vast majority of ants, harboring in the colony, will survive and keep it thriving. With all of the advancements in baits and baiting technology, ant control “has not changed much in the last 50 years. Finding and destroying the colony is still the secret to ant control,” Tucker said.

When it comes to carpenter ants, Tucker urged pest management professionals to seek out the colony at night. Because carpenter ants are nocturnal, PCOs will typically see 300 to 400 times more ants at night than any other time of the day. This increased activity gives pest management professionals more trails to trace back to the colony and bait. Tucker said tracking carpenter ants at night is not always convenient and goes against standard business practice, but he said the potential payoffs make it worthwhile. “Why don’t we look for ants at night? Because that’s not when our businesses operate,” Tucker said. “It goes back to changing the mindset of ant control.” Once the carpenter ant colony has been located, it can be destroyed either directly, by drenching, or indirectly, whereby foragers carry bait back to the colony.

Another serious pest is the Pharaoh ant, according to Tucker, particularly in hospitals. If Pharaoh ants have nested inside a structure and are entering from the exterior, PCOs may want to consider incorporating bait products into their control program. However, it’s not enough to simply place bait near suspected activity sites, according to Tucker. Instead, he suggests numerous bait placements be made in a cloverleaf fashion in and around infested hospital rooms. He learned this lesson while serving as a consultant for a hospital that had a serious Pharaoh ant infestation. The hospital had been dealing unsuccessfully with an ant infestation in a particular room for nearly 40 years. After placing bait in only one or two locations where Pharaoh ant activity was present (e.g., near an air conditioner, window, etc.), ants would be controlled temporarily, but return annually. Years of failure followed before Tucker changed his approach. “I went back to the drawing board and changed my treatment strategy,” he said. Tucker said he recommend-ed treating not only the infested room, but the rooms that bordered next to, above, below and on the other side of the wall, as well as in the air-handling rooms, until nearly every room was baited. Since changing the control program, he hasn’t received a single complaint from the hospital.

“Successful ant control requires a mindset change,” he said. “If you want to do it right, you need to identify the species causing the problem and then design a control program that takes into account the unique behavioral characteristics of the particular ant causing the problem.”