[New Technology] Liquid and Gel Ant Baits: What's New?

Editor’s Note: According to PCT’s most recent readership study, ants are the No. 1 structural pest in the United States. To address the product needs of this expanding marketplace, manufacturers have introduced a number of new liquid and gel ant baits in 2007. A general discussion of ant baits by noted author Stoy Hedges follows, along with brief product profiles from manufacturers about their latest liquid and gel product offerings. Advancements in granular baits will be featured in a future issue of PCT magazine. Manufacturers, if you have a granular bait product you would like profiled, contact PCT Editor Jodi Dorsch at jdorsch@giemedia.com.

Although ant baits have had a long history in pest control, in recent years there has been a renewed interest in their development and use. This new popularity is due to public pressure to reduce pesticide use, new insecticides well-suited for bait formulation, and the numerous advantages of using baits, which include:

• baits are more target-specific than contact insecticides;
• baits are more cost-effective compared to labor-intensive inspections to locate nests (which often are unsuccessful) and treatment strategies that involve invasive techniques like drilling and dusting; and,
• baits can be used in sensitive places such as commercial kitchens and food preparation areas, and around electrical equipment. On the negative side, baits tend to be slower acting than sprays or dusts. Therefore, the professional needs to educate a client about how baits work and the amount of time it takes to obtain control with them.

WHY BAITS? Ants exhibit a unique aspect to their feeding behavior as food is circulated and recirculated through the colony. Worker ants will drink liquid food while foraging in the field and return to the colony with solid food. Upon returning to the colony, these workers regurgitate consumed gel baits and feed other members of the colony, including the queen(s) and larvae. Solid foods are fed to larvae who then regurgitate partially digested food to workers. Bait formulations of insecticides, therefore, work very well for controlling ants.

An effective bait formulation contains food ingredients on which the target ant will readily feed. The active ingredient (toxicant) must kill slowly enough to allow the ants to return to the colony and feed the bait to all the other members of the colony.

A variety of baits can be used successfully, but each is dependent on the particular ant colony involved. For example, a pavement ant colony in one home will feed on one bait, but in the house next door pavement ants will not touch that same bait, although manufacturers are working hard to develop products with an increasingly broad spectrum of control. Nonetheless, it is common for several baits to be tried before the ants find one they will feed on for an extended period — long enough to circulate enough bait through the entire colony.

PRE-BAITING SURVEY. The choice of baits to use for control typically will depend on the food preference of the ant. Another crucial component of the program is good sanitation so that the bait is not competing with other food sources. The professional should stress this point when discussing the program with the client.

A beneficial part of an inspection may be a pre-baiting survey that will enable the professional to map foraging trails. A non-toxic survey bait, such as honey, jelly, peanut butter, and diced crickets or mealworms on white index cards can be placed in various locations both indoors and outdoors. On the inside, locations to prebait include windowsills, electrical outlets, pipes and drains, sinks, countertops, toilets and other moisture sources. Outside, survey baits can be placed at corners of windowsills, at corners of the foundation, around entrances and exits, at the base of trees, outside tree holes, and at incoming and outgoing plumbing and electrical lines. Survey baits should be left in place at least 15 to 30 minutes (an hour or two is better) to give the ants enough time to discover the baits and recruit enough ants to establish a trail.

After the survey is finished, the survey baits in active sites should be removed and replaced with a variety of commercial ant baits to determine which one is preferred by the ants. Ideally, this choice test would include at least one representative from each of the three basic food attractants used in commercial ant baits — proteins, carbohydrates, and oils.

After placement of toxic baits, follow-up visits generally are necessary to check if the ants are feeding on it, if more bait is needed, or if it needs to be switched with another bait. The ants should be allowed several days to feed on the baits before initiating any follow-up efforts to control the remaining ants. It is important to note that many residual pesticides are repellent to ants, so careful handling of the baits following the use of other products is necessary to prevent contamination. For best results, baits should be stored separately from other pesticides.

BAITING TIPS. Regardless of which bait product(s) is used in your control program, the following tips should be followed for successful use of baits against ants.

1. The biggest mistake made with ant baits is to place them and then forget about them until the next scheduled service visit. Ant baits should be checked within one week at least, but sooner may be better for some situations. Are the ants finding the bait? Has there been noticeable feeding on the bait? If not, switch baits, and if more trails are found, place additional baits. Baits cannot work if they are not fed upon by the target ants.

2. Place baits as closely as possible to the ant colony. If an acceptable food source is available close to the colony’s location, that food source is likely to be more heavily exploited. When possible, place ant baits where the trail is exiting a wall or crack in a slab.

3. Place ant baits along edges and corners wherever possible since ants like to trail along “structural guidelines” formed by the edges of cabinets, the edges of a wall or a crack in concrete, along corners, the edges of landscape timbers, the edge of a tack strip under a carpet, along wires and plumbing pipes, etc.

4. Place baits in electric outlet boxes in walls, especially when dealing with Pharaoh ants because these ants commonly use electric wires to move throughout buildings. Ant bait stations do not fit in these boxes, so a gel ant bait placed in a piece of plastic straw will usually be needed.

5. Remove other potential food sources by advising the customer of the importance of cleaning up food particles, grease deposits, etc., as much as possible.

6. Not placing enough bait placements is another common reason ant baits might fail in controlling an infesatation. Each active foraging trail should be baited because that trail could be from a separate colony, especially in the case of Pharaoh ants. Follow-up inspections are helpful in identifying new ant trails.

7. Avoid placing baits on treated surfaces or applying pesticides over bait placements.

8. Outside bait placements are important, particularly for Pharaoh ants, which commonly forage outside during warm weather. In fact, research has indicated that most foraging by Pharaoh ants is completed outside rather than inside. Outside surfaces should be inspected for trails and at least one bait placement applied along each trail. With the coming of autumn, the nectar in flowers and nectarines decreases or disappears and the honeydew is washed from the plants by rains. During spring, aphid and mealybug populations are at low levels which reduce the available amount of a preferred food source. At these times, sweet-loving ants, such as the Argentine ant, may feed much more readily on ant baits. The fall and spring of the year, therefore, may be the best times to use ant baits for this species and others.

9. Some ants just do not feed on baits as readily as others, so take this into account when designing an ant control program.

CONCLUSION. Due to market demand, a growing number of ant baits are available for commercial use. However, before selecting those products that you plan to incorporate into your ant control program, study the academic literature, talk to your colleagues, read trade magazine articles and ask questions of your manufacturer sales representatives. Only then will you be confident in what products may be right for your particular region of the country.

Product Profile: 
DuPont Advion Ant Gel
DuPont Professional Products
www.proproducts.dupont.com

The U.S. Environmental Protection Agency has granted regulatory approval for DuPont Advion ant gel.  Advion ant gel will provide pest management professionals with consistent, broad-spectrum control of multiple ant species including all key sweet feeders, plus carpenter ants and many others, the company said. 

Powered by the MetaActive compound, Advion ant gel leverages the ant’s own enzymes to provide colony control, even when multiple queens are present. Its attractant formulation will ensure pest management professionals gain broad spectrum control. According to DuPont, Advion ant gel also has an excellent toxicological profile, with an EPA-classified Reduced Risk active ingredient.

“We’re proud to introduce a new member of the Advion family to our customers, who have come to rely on the power of its chemistry and its superior environmental profile,” said Mike McDermott, global business leader for DuPont Professional Products. “Pest management professionals who are looking for infestation control of sweet feeders, carpenter ants and other species will now have the reliable, thorough insect control they expect from the Advion brand.”

Product Profile:
InTice Thiquid Ant Bait
Rockwell Labs Ltd
www.rockwelllabs.com

New InTice Thiquid Ant Bait from Rockwell Labs Ltd is a thick syrup bait that is effective on a wide range of pest ants, the company reports. InTice Thiquid is packaged in fully labeled 4-ounce dropper bottles for spot applications directly on surfaces. It also can be squeezed easily into Rockwell’s BaitPlate Stations. To make a liquid bait, InTice Thiquid can be diluted with up to four parts water to make a 1 percent borax solution. Economical 1-gallon jugs are also available. Like all InTice products, InTice Thiquid can be used in certified organic facilities.

Product Profile: 
Whitmire Micro-Gen’s Advance Baits
Whitmire Micro-Gen
www.wmmg.com

388B Advance Ant Gel Bait from Whitmire Micro-Gen is an easy-to-use gel that’s as effective as liquids, the company said. Crack & Crevice® application cleans up visible infestation symptoms quickly, discreetly. The product contains 5.4 percent borax, is labeled for indoor and outdoor use and is packaged in 20 x 30 gram reservoirs. 388B Advance Ant Gel Bait controls the following ants: acrobat, Allegheny, Argentine, big-headed, cornfield, crazy, ghost, harvester, little black, odorous house, pavement, Pharaoh, pyramid, white-footed, thief and honey.

381B Advance Liquid Ant Bait is highly attractive to sweet-loving pest ants. It contains 1.3% borax, is labeled for indoor and outdoor use and is available in 1-gallon containers. 381B Advance Liquid Ant Bait controls the following ants: acrobat, Allegheny, Argentine, big-headed, carpenter, cornfield, crazy, ghost, harvester, little black, odorous house, pavement, Pharaoh, pyramid, white-footed, thief and honey.

Product Profile:
Maxforce Ant Gels
Bayer Environmental Science
www.bayerprocentral.com

According to Bayer Environmental Science, Maxforce ant gel baits are ideal for eliminating inaccessible ant colonies with the exclusive Maxforce Domino Effect, a delayed action kill that allows foraging worker ants to take bait back to the colony — wherever it may be hidden. Gel baits are less intrusive, controlling ants with less pesticide when compared to broad-spectrum sprays, the manufacturer said. 

Maxforce ant gel baits may be applied as spots or into cracks and crevices both indoors and outdoors, and will control ant colonies that may be coming from under a home’s foundation, deep in wall voids or high in trees. Simply place Maxforce ant gel in areas of ant activity, next to ant trails and near ant nests. When used in commercial food-handling areas, such as kitchens, pest management professionals should apply gel bait in cracks and crevices only.

Maxforce FC Ant Killer Bait Gel combines a high-moisture formula and fast-acting fipronil to control ant colonies fast; it can be easily applied to cracks and crevices with the Maxforce Bait Injector. Maxforce Carpenter Ant Bait Gel with fipronil contains a special Honeydew formula that takes advantage of a preferred food for carpenter ants that naturally comes from aphids. 

Product Profile: 
Optigard Ant Gel Bait
Syngenta Professional Products
www.securechoice.us

In June, Syngenta Professional Products introduced Optigard Ant Gel Bait containing 0.01 percent thiamethoxam, the same active ingredient found in Optigard ZT insecticide. The new product, a highly palatable ant bait that effectively controls a wide range of ant pests, features a number of customer-friendly characteristics, according to the manufacturer.

Thiamethoxam is a non-repellent, second-generation neonicotinoid insecticide that is readily transferred among individuals within ant colonies to control workers, brood and queens. What does that mean for pest management professionals? “The neonicotinoids tend to act slowly, which allows transfer of the active ingredient to the rest of the colony, resulting in excellent control,” according to Dr. Deanna Branscome, technical representative, Syngenta.

Thiamethoxam targets the nicotinic acetylcholine receptors in the insect’s nervous system, resulting in death of the ant. The mode of action is significantly different when compared with other classes of insecticides commonly used for ant control, Branscome said.

Extensive laboratory and field tests were conducted to determine the efficacy of Optigard Ant Gel Bait against a variety of ant species. In one such test, Apex Bait Technologies (Liang 2006) conducted laboratory tests to determine the activity of the bait against Argentine ant workers and queens. The tests revealed:

Optigard Ant Gel Bait killed 97 percent of workers by three days and 100 percent by seven days. Mortality of queens exposed to Optigard Ant Gel Bait was 73 percent at 24 hours and 100 percent at three days.

In addition to palatability and effective control, the proprietary gel formulation is clear, non-staining and low in odor. “If you have a formulation with some color it can be visually unattractive to a customer if it is placed in or around a home,” Branscome said. “It’s important that a product be aesthetically pleasing to your customers.”

In addition, the bait maintains its integrity for at least two weeks following application, even at elevated temperatures, the company said.

Why introduce another bait product into the already crowded ant field? “In developing the product, we considered several formulations and found that gels were the most versatile, so we set out to develop Optigard Ant Gel Bait as an odorless, colorless, clear formulation that controls a broad spectrum of ants,” Branscome said. “From the outset we wanted to make sure we had a product that was very competitive, so we invested a lot of time and energy in developing the right formulation.”

Optigard Ant Gel Bait is the second product introduced by Syngenta Professional Products under the Optigard brand. It follows Optigard ZT, an efficacious foam zone treatment featuring thiamethoxam. “In the future, we will continue to expand the uses of this high performance, patented chemistry and the Optigard brand,” Branscome said.

Product Profile: 
Gourmet Liquid Ant Bait
Innovative Pest Control Products
www.antcafe.com

EPA has approved changes to the Gourmet Liquid Ant Bait label. The new label allows for the use this product for the control of “all roaches and common household ants” and for the removal of all precautionary statements.

At the request of PCOs using the company’s Ant & Roach Café RTU (prefilled and ready to use) bait station, Innovative Pest Control Products also has modified the packaging for these stations. The new Professional Package contains 24 RTU bait stations and 24-double sided tapes in one bilingually labeled box.

Gourmet Liquid Ant Bait is certified organic and is being used with great success to control tramp ants, such as Argentine ants, that infest citrus and grape crops in California, the company reports.

Innovative Pest Control Products said that because this product has proven efficacious, can be used indoors or outdoors, has a favorable toxicity profile, can target pests without harming beneficial insects and can be used to draw pests away from areas of current infestation,  it is an effective tool for pest management professionals to consider when developing an IPM program for schools, medical facilities, homes and sensitive accounts.