Asian Needle Ants Push Into The Carolinas

http://www.newsobserver.com/2013/03/17/2751050/make-way-for-6-legged-samurai.html#storylink=misearch

Those Darn Ants!

Foraging Argentine ants (Photo: Alex Wild).

How many times have you been called to the teachers’ lounge, a classroom, or bathroom because someone has seen ants in and around a sink or other water source? Let's run through what might be a typical scenario:

Your look around and rule out the presence of a leak or other plumbing issue. You determine that the ants are just after whatever water is in the sink. You spend some timing looking around, but because the ants haven’t established a foraging trail, you can’t figure out how they are getting in.

So you do what you can in this situation – perhaps you make a crack-and-crevice application into any obvious cracks or gaps in an effort to keep the ants out. Maybe you even seal up a couple of gaps with some caulk or other sealant. You go through your regular spiel about making sure that food is stored properly, garbage is taken out regularly, excess water is wiped up, etc. And you’re done.

Until you get another call about ants in the same area – just a couple of days later! So, you go back, look around again – this time taking even a little more time to check for potential entry points.You know that for optimal results, you really need to find and treat the source (i.e., the nest). So you go outside and look for a nearby ant nest but find nothing. You watch the ants closely, but never see where they are coming from or going to. So you make another, more thorough crack-and-crevice application into the gaps in the area. You treat a few extra openings that you somehow missed before. And you’re done.

You wish! You get yet another call about ants in the same area. So, what can you do now? What is going on?

Well, I can tell you that I’ve had this exact same problem occur at my house – in my kitchen around the sink. And I tried everything that I wrote about above. I checked outside for a nearby nest but found nothing. Since I could find no nest, I realized that my best bet would be to attempt to keep the ants out of my house. So I treated all the obvious gaps with a crack-and-crevice insecticidal spray. I sealed up whatever openings I could see. Yet, I kept getting ants around my kitchen sink. I watched the ants carefully to try and determine exactly where they were getting in. But I could find nothing, because while there were several ants around the sink, there was never a real distinct foraging trail.

Ants recruited and feeding on jelly 
(Photo: Patty Alder).

Then it hit me: I realized that in order to find the entry point(s), I needed a distinct foraging trail. So I placed a very small dab of apple jelly on a piece of cardboard, placed it on the counter near the ants…. and waited. It didn’t take long – maybe 20 minutes or so – for more ants to show up (see photo at right).

Pretty soon, I had myself a pretty distinct trail of ants going from my kitchen sink to…. a small opening where the caulk had come out in an area on the counter right behind my sink. (see photos below). A small opening that I had overlooked! So I treated that opening with a crack-and-crevice spray and guess what? No more ants!

Foraging trail can be followed from the jelly down 
the window frame (Photo: Patty Alder).

Ants were coming in through a gap in the counter 
behind the sink (Photo: Patty Alder).

If you have this issue with ants, set out a bit of jelly on an index card in a couple of areas where you are seeing the ant activity. If the ants are in a classroom, make sure you explain to the teacher that he/she needs to keep the children away from the area so as not to interfere with the ants’ activity. Check back in about 30 minutes for a trail of foraging ants and carefully follow the ants to see if you can determine how they are gaining entry into the area. If jelly does not seem to attract the ants, you could try a small piece of cheese or a potato chip (I wouldn’t use peanut butter in schools because of all the issues with allergies). Once you figure out where the ants are coming in, you can treat that opening with a crack-and-crevice application. You may even want to seal up the opening after it has been treated.

Good luck and happy ant hunting!

Ants: Facts and Fiction, by Eleanor Spicer Rice, NCSU Entomology Dept.

Think you’re an ant expert? Quiz yourself with these quirky questions about some of our favorite insect friends. The answers may surprise you!

1. (True/False) Most ants are pests.
2. (True/False) All ants have nests.
3. (True/False) There is an Argentine ant colony right now with billions of workers that spans nearly 4,000 miles.
4. (True/False) Ant workers are both male and female.
5. (True/False) Smaller ants never grow up to be bigger ants in the colony.
6. Which of the following is an effective home remedy for killing fire ants? (A) dumping grits on the nest; or (B) dumping a pot of boiling water on the nest 

Time to check your super ant knowledge!

Question 1: Most ants are pests. 

This is false! In fact, most ants are NOT pests! Of the more than 30,000 ant species in existence worldwide, fewer than 100 of them are pest species. And in North Carolina alone, fewer than a dozen of the over 250 known species are pest species.

What do all of the other ant species do? Ants are a valuable part of our ecosystem. Because they fill so many jobs, from predators and scavengers to plant protectors, they play a central role in maintaining the ecological balance and biodiversity present in our natural world.

Aphaenogaster carolinensis (Photo: Alex Wild, alexanderwild.com).

Some ants, like a group in North Carolina called Aphaenogaster, are responsible for planting seeds in the forest floor. Many seeds have evolved a tasty outer layer that ants love to snack on. After they remove this delicious shell, the ants plant the seeds in the ground. Without Aphaenogaster and ants like them, we would be missing a lot of our forest herbs.

Ants also protect plants from harmful insects and even aerate the soil as they dig out their nests. It has been estimated that ants turn more soil than earthworms!

Question 2: All ants have nests. 

This is also false! African driver ants and army ants do not have nests. These restless wanderers travel around without stopping, eating everything in sight. When the driver ants come through villages in Africa, residents pack up all their things and move out, allowing the ants to clean up after them. Check out the video below to see army ants in action!

Question 3: There is an Argentine ant colony right now with billions of workers that spans nearly 4,000 miles. 

It’s true! Argentine ants are little brown ants that look a lot like odorous house ants, also known as sugar ants, which are pretty common around here. Unlike odorous house ants, Argentine ants don’t fight each other, which allows them to form tremendous colonies called supercolonies like the one that spans nearly 4,000 miles of the Mediterranean coastline. We have a couple of supercolonies in North Carolina, too! Although they don’t sting, these miniature marauders are ruthless and can wipe out native ant populations when they move in. As we learned from question 1, we need our native ants!

Question 4: Ant workers are both male and female. 

False! All ant workers are females. Ant colonies have a female queen and female workers. Colonies only produce males once or twice a year. However, males don’t do any work. Their only purpose is to eat and mate (sound familiar, anyone?). After mating season is over, the female workers take girl power to a whole new level by either kicking the males out into the cold or eating them.

Fire ants range in size from 2-6mm. Nests typically contain workers in a range of sizes
(Photo: Texas A&M Univ.)

Question 5: Smaller ants never grow up to be bigger ants in the colony. 

It’s true! Although some colonies have workers of many different sizes, the littlest ones are fully grown. That’s because ants have something called complete metamorphosis. That means they’re like butterflies, flies, and beetles in how they develop from egg to adult. Just how a beetle baby is a grub, an ant baby is a grub-like larva. Ants pupate like butterflies and moths do, too. After they pupate, they emerge as fully grown ants.

Question 6: Which of the following is an effective home remedy for killing fire ants? (A) dumping grits on the nest; or (B) dumping a pot of boiling water on the nest.

The answer is B. A lot of people have tried dumping grits on a fire ant nest, but it just doesn’t work. First of all, as many North Carolinians can attest to, grits aren’t poisonous! Second of all, ants have tiny waists and can’t process grits by themselves.

Even so, some people insist they’ve poured grits on fire ant nests and come back to find the fire ants all gone. This could happen, as fire ants move around frequently and don’t like people tampering with their nests. However, it’s important to note that these fire ants just moved; they were not killed by the grits.

Dumping boiling water over the nest can put a swift end to fire ant mounds. This is because the scalding water boils the ants alive. Adding a little detergent to the water can increase effectiveness, too! The water must be boiling, however. Fire ants are used to flooding and can make rafts out of workers. If the water is not hot enough to kill them, they can just float away.

Using boiling water to treat a fire ant nest does have its limitations. First, you've got to get the boiling water outside to the nest without scalding yourself. Second, the boiling water can actually damage and/or kill any vegetation that's around the treated area. So, while it does work, boiling water is not always the most practical way to treat a fire ant nest.

Tips for Effective Ant Baiting

Baiting for ants has some advantages over other types of insecticides. First, baits can work when the nest cannot be found or it is inaccessible for treating with other chemicals. Second, baits pose less of a risk to children and staff by reducing the risk of possible contact with any toxic chemical. Third, baits can kill the entire colony whereas most insecticides sprayed on a surface kill only the workers that contact it. 


Remember, baits are effective only if they are eaten and not all baits are equally attractive to different ant species. Make sure the bait you use is acceptable to the ants. Place a small amount of bait where you see ants foraging and then watch their reaction for a few minutes. If the ants show no interest in the bait, try another bait until you find one that they readily feed on. Once you find a bait that is acceptable to the ants, several other factors determine its effectiveness:

• Sanitation - Baits work best when there are no other food sources available to ants. Keep areas clean so ants are not "distracted" from locating and feeding on the bait.
• Proper placement - Bait should be placed in known or suspected areas of ant activity. Be sure that bait is placed out of the reach of children and staff. Never place bait directly on countertops where food is prepared or in an area where it will get wet and/or contaminated.
• Quantity - Make sure you put out enough bait and that it remains fresh. If the ants carry away all of the bait, then they may leave the area and go elsewhere before enough bait is spread within the colony. Ant species that are capable of producing large colonies, such as the Argentine ant, will most likely require more than one application of bait.
• Durability - Baits will eventually become unacceptable if they are exposed to high temperatures, rain, and sunlight. Check baited areas for signs of ant feeding and replace baits that are no longer acceptable to the ants.
• Patience is important to successful baiting. Most ant baits are slow-acting. Explain to students and staff that they may continue to see ants for a week or more after baiting. It is important that the ants are able to return to the nest with the bait so it can be fed to other members of the colony. Ask people not to disturb or kill the ants.
• Remember, if you determine that chemical control is needed to successfully control the ants, never spray in areas baits have been applied. If the baits are contaminated, the ants will avoid the bait.

Below is an "Ant Baiting Decision Tree" developed by Jules Silverman, NCSU Charles G. Wright Professor of Structural Pest Management. You may use the Baiting Tree as a tool in determining what actions to take in order to successfully bait for ants.