Ant ID and Control

Ant antics

There are hundreds of species of ants in the US and thousands across the world.  Ants have fascinating lifestyles, forming complex societies that can do remarkable things.  In nature they are prey, predators and scavengers.  Their nest building loosens and aerates the soil.  Ants pollinate some plants and carry away and “plant” the seeds of others.  When they are not in your house and not a harmful species they should be left alone.

It’s when ants intersect with humans that problems arise.  Some ants are a threat to humans, but most are just a nuisance problem.  The tiny sweet eating ants in your home aren’t going to harm the house or you, but many people can’t tolerate them.   I know there are some tiny red ants living in my vegetable garden that I detest because they attack and bite me while I’m planting or weeding.  But they aren’t fire ants and the bites less serious than mosquito stings, so I don’t go on a killing spree.

I confess I can’t tell most ant species from each other, although I can identify a few.  Ants can be hard to identify unless you are an entomologist.  I’m going to give some brief descriptions of ants that can cause serious problems.  But ant control is basically the same if you are doing it to remove a pest or a nuisance species, so I will cover control of ants at the end of the article.  First let’s discuss some ants that do more harm than others.

Allegheny mound ant Formica exsectoides

This ant species is found from the east coast to just west of the Appalachian Mountains. It can either be a reddish color or black and sometimes both colors exist in the same colony.  It’s fond of open woods, or open undisturbed areas.  It sometimes appears in tree and shrub nurseries and home landscapes.  They build a large mound in the sun, which helps incubate their eggs and larvae. 

If Allegheny ants need more sun they try to kill any vegetation that shades the mound.  They do this by biting the plant and injecting formic acid.  They can kill good sized trees over time with repeated injections.  Plants being attacked by these ants often have brown blister like bumps on trunks and stems.

Allegheny ant mounds are large and quite conspicuous, up to 3 feet high and 6 feet wide.  From time to time the colony will split and form a new mound, spreading across the area. Besides the ants killing any plants near the mounds they also aggressively attack anyone who disturbs the mounds. Homeowners may want to eliminate them.  These ants are hunters of other ants and insects, although they will also scavenge for honeydew from aphids, plant nectar and other sweets.  They rarely enter homes and won’t nest there.

Carpenter ants (Camponotus spp.)

The black carpenter ant (Camponotus pennsylvanicus). is one of the most common species of carpenter ant in the US but there are many species. These large black ants cause a lot of concern for homeowners and they can cause damage to homes.  These ants don’t eat wood like termites do but they tunnel in it to make homes and can do structural damage. They also tunnel in trees, hollowing out the inside.  They prefer wet or rotting wood and if carpenter ants invade the homes structure it almost always had water damage in the area first.

If you see a few of the large black ants in the house in the summer, it may not be cause for worry.  These ants often range widely for food and their nest may be outside away from your home.  If you see them in the winter though, it probably means they have a nest in the house somewhere, unless you are bringing in firewood they may have been in.  If you see the mating stage, flying carpenter ants, in the home in large quantities you almost certainly have a nest inside.

Carpenter ants in the woods are part of natures recycling plan and do no harm.  They should be left alone in this circumstance.  But you may want to eliminate them from garden areas as they are a species that herds and protects aphids, which are not good for your plants.

Carpenter ants are hunters, herders and scavengers. They hunt and eat insects including smaller ants, they “milk” aphids for their honeydew secretions and they scavenge for sweet liquids, like soft fruit juices, honey, nectar and human foods and for protein sources like dead insects and small animals.  Most foraging is done at night.  Different species of carpenter ants may prefer different food sources.

Red Imported fire ant Solenopsis invicta

This is a much-feared ant that has steadily been working it’s way from the south to the north.  The first two segments of the fire ant body are often copper brown and the last segment black, but some worker ants can be all red or all black.  They have 10 antenna segments and two spike-like projections in the constricted area before the abdomen.

The fire ant has a bite that feels like fire as the name suggests, and it’s very aggressive. It uses its jaws to grasp and hold onto a victim then injects them with an alkaloid venom called solenopsin from a projection on the abdomen, (like a bee stinger). On a human this cause a red painful area with a white pustule in the center. If an animal or even human gets enough bites it can kill them.  They often kill ground nesting birds and baby animals on the ground.

Fire ants may build large mounds in open areas similar to the Allegany ants but they also nest underground, often in moist areas near ponds, ditches, rivers and under piles of brush and debris and so on.  They may nest under concrete slab foundations or patios. You do not want to get close to these nests without protection because the ants will pour out and attack anything that disturbs their home.

After heavy rains and flooding the ants may be seen migrating in huge clusters to a better place.  In flood waters they may form rafts of ants.  You want to stay well away from these migrating/floating groups.

Fire ants feed on tender plant growth and can cause considerable damage to gardens and crops.  Because they damage wildlife populations, crops, and are a hazard to humans they should be eliminated in any area they are found in.  Since they are dangerous it’s best to call a professional exterminator to kill these ants.

Crazy Ants Nylanderia fulva,

Fire ants have caused much grief for southern gardeners since they worked their way up from South America many years ago.  Now a new invading ant is taking over fire ant territory, and since it may survive cooler weather better than fire ants, might become a problem for northern gardeners if it is carried north. This ant is also called Rasberry Crazy ant (named for the discoverer, not the fruit, hence the spelling) but the official common name is Tawny Crazy ant.  It too comes from South America.  It’s a non-descript, reddish brown medium sized ant.

They get the name Crazy ant because of the huge erratic colonies they build up; often the Crazy Ant population in an area will be 100 times more than all other ant species combined.  They also seem to move erratically in their search for food. They eat anything, including other ants, and eliminate all competing species, even fire ants.  The worst thing about them is that unlike fire ants they invade homes, often in the thousands, and are very hard to control.  They often damage electrical systems and equipment by eating components or shorting them out.  

The key to keeping them from spreading north is to watch for ants hitchhiking in things like potted plants, camping equipment and RV’s.  These ants do not fly at any stage of their life so their spread is solely by foot travel or hitchhiking.  Be very careful with nursery plants you receive from the south, particularly those from Texas and Florida.  While they may have been inspected, there’s always a chance a crazy ant could slip through.   And if you visit the south please be very careful not to bring ants back with you.

Now let’s discuss some ant myths as well as control.

Ants and peonies

When people look at peonies and peony buds they often notice ants on them and that makes for some interesting conversation.  Ants are neither bad for peonies nor good for them.  Peonies have many nectar glands, they occur in the flowers reproductive parts, starting when the buds enlarge and lasting at least to the green seed pod stage.  Ants enjoy this nectar.  But peonies don’t need ants to eat the nectar.  Ants don’t help the buds open by eating “sticky” nectar off and they don’t generally pollinate the peony flower either.  Ants do defend a food source to some extent and may keep things like caterpillars from eating the flowers.  But this is a minor benefit in most cases.

Peonies without ants will open their flowers just fine.  And the ants don’t harm the flowers so there’s no need to control them. There’s plenty of nectar for everyone.  Using pesticides in this case, even organic ones, is not good environmental stewardship.  I saw a recommendation to sprinkle powdered sugar on peony buds to remove ants.  That would probably bring a whole lot more ants, because ants love sugar.  And that kind of tinkering might well prevent peony buds from opening well or looking good.  It might also cause mold to form.  Please don’t try that nonsense.

Ants don’t show up on every peony plant.  Some varieties seem to attract more ants than others, and what’s available in your area for ant food may determine whether you have ants on your peony flowers or not.  If you object to ants being on flowers you are cutting for a bouquet you can shake the flowers or dip them slowly into cold water upside down to remove ants.

Ants and cornmeal

Here’s another common myth concerning ants.  Someone wants an organic solution for getting rid of ants and someone else recommends sprinkling cornmeal- or grits- where the ants are to get rid of them.  Somehow the idea that ants eat cornmeal or grits then bloat and explode got started and it’s hard to make that false idea die.  There’s no evidence that ants ever die from eating cornmeal or grits.  And the biology of the ant’s digestive system makes that explosion pretty much impossible.

Ants don’t digest solid foods they may gather, like pollen grains, pieces of dead caterpillars, leaves and so on.  The solid bits go into a special pouch area and get carried back to the nest where they are fed to the ant larvae, which do digest solids.  The larvae then regurgitate a liquid which is shared through the colony of both worker ants and larvae.  There’s no gas build up since they have the ability to regurgitate.  Researchers have fed cornmeal and other substances to ant colonies with no problems. 

The nonsense of cornmeal killing ants probably got started because cornmeal is often used in ant pesticides as an attractant.  A poison is liquefied then added to cornmeal which absorbs it.  The cornmeal makes it easier for the ants to carry the poison deep inside a nest and the starch in cornmeal is tasty to ants.  But the cornmeal needs to be saturated with poison before it kills the ants.

When you sprinkle cornmeal around in the garden you aren’t killing pests, you are attracting them.  You’ll get ants as well as mice and squirrels and other critters.  And cornmeal can also mold and look and smell nasty.  When you hear someone recommending using cornmeal to make ants explode just laugh.

Controlling ants

By reading the section above you now know cornmeal doesn’t kill ants.  So lets talk about how you can get rid of them.  We’ll call it controlling ants because you are never going to totally eliminate all ants in your environment.

First thing to try is disruption of their food supply and nesting areas.  This is pesticide free and generally environmentally friendly.  In the home eliminate food crumbs, food left out on counters, even spills that aren’t cleaned up on counters and tables. An ant colony can feast on a smear of jelly left on a counter.  The cookie crumbs under the highchair are like a banquet.

If you have a large ant problem you can put pet food dishes in a slightly larger dish filled with water to make an ant moat.  Some ant species are attracted to sweets and others to protein sources. Since ants follow a scent trail of other ants to food sources clean counters and floors frequently.

Now disrupt their nesting areas.  Inside that may be drying out wet areas to get rid of carpenter ants and replacing wet damaged wood. There may be a rotting tree close to the house outside, or a pile of old lumber or firewood that needs to be removed.  The small household ants may nest in crawlspaces, basements, under carpets, even flower pots.  Try to track them to where they are coming from and eliminate their home.  Yes, some will just relocate but if you eliminate their food sources and constantly disturb their nests they will relocate farther away, out of your home.

Outside eliminate ant mounds in the yard as soon as you see them, before they get large.  Rake over them with a sturdy rake and pour a bucket of hot soapy water on the mound area. Contrary to popular media belief, hot soapy water probably won’t kill many ants, but if you disturb their nests often enough they may relocate to an area far away.

Remember to be very careful disturbing the nests of fire ants. They can seriously harm you if you get enough bites. It’s probably best to hire an expert if you suspect you have fire ants.

Pesticides

Let’s just get the boric acid/borax thing over with first.  It’s the most common “home remedy” for ants circulated in social media and among gardeners.  And yes, boric acid kills ants, it’s one of the most common ingredients in commercial ant control products and get this- it’s a registered pesticide!  When you use boric acid, whether you buy commercial products or mix up some concoction you read about, you are applying a chemical pesticide, not a “natural” product. 

And despite all the claims boric acid is not harmless to children and pets.  It’s not always safer than other chemicals either. It’s a moderately safe pesticide if used correctly.  And many of the home remedies that include mixing borax acid or a close sub, borax (they are not the exact same thing by the way) are much less safe than a commercial product.  Here’s why.

Boric acid in commercial pesticides is mixed with attractants that attract ants or cockroaches but aren’t that attractive to pets and kids. The directions, which you should follow because in pesticides they are the legal way to use them, will tell you the appropriate way to apply the product and how much to use. These pesticides are often packaged in a way that makes it less likely a child or pet will consume them, such as in the little ant buttons or other types of bait stations.

When people go to the drugstore and buy some boric acid or the grocery to buy borax, a laundry product, and then mix it with jelly or honey they are making a pesticide that is attractive to kids and pets.  When you are spreading it on trees or other things outside, like some media posts urge you to do, you are also attracting bees and other helpful insects and wildlife, all of which can be harmed or killed by the product.  It kills all insects, not just harmful ones.

Boric acid used to be prescribed as an eyewash and as a douche.  Medical experts have quit advising it for those uses because frequent exposure to the product has been found to cause kidney damage and other problems.  In the late 80’s there was a popular folk remedy floating around that advised moms to coat a pacifier with honey and boric acid to ease sore gums.  This caused seizures in infants.  A nursery disinfectant with boric acid caused the deaths of several babies in the 1960’s.

Boric acid is not absorbed easily through the skin except on wounds.  Boric acid powder can be inhaled, and chronic exposure will cause problems. Getting powder in the eyes will cause severe damage. But the most common way to be poisoned by boric acid is by consuming it.  Normally pets and children would not eat enough boric acid to make them terribly ill but when someone mixes it with jelly, honey or maple syrup they may consume enough to become seriously ill or die.

Consumption of boric acid (and borax) causes vomiting, diarrhea, listlessness, fever, skin rashes, seizures, kidney and other organ damage, coma, and death.  Young children seem to be affected more severely. Children have died from boric acid poisoning. There have been many pet deaths from boric acid poisoning. Boric acid causes fetal abnormalities in animals and possibly humans. It causes atrophy (shrinking)of the testicles in animals. Poisoning can be acute- from one large dose- or chronic- from repeated small doses.

Boric acid is not harmless to plants either.  Boric acid products on plant foliage will dry it out and cause leaf death.  Too much boric acid in the soil causes plant death.  This can happen when boric acid products are leached into the soil by rain or irrigation.

So, the bottom line is boric acid is a pesticide and can cause poisoning like all other chemical pesticides.  If you mix up concoctions with it, they must be placed in containers that pets and children cannot get into.  Sweet mixes should not be openly spread around in the environment where they can kill bees, helpful insects, and wildlife.  If you use a powdered mix pets should not be able to walk through it.

Here’s some links about toxicity of boric acid.

http://pennstatehershey.adam.com/content.aspx?productId=117&pid=1&gid=002485

https://onlinelibrary.wiley.com/doi/pdf/10.1111/j.1556-4029.2007.00420.x

http://npic.orst.edu/factsheets/boricgen.html

https://medlineplus.gov/ency/article/002485.htm

http://adc.bmj.com/content/archdischild/58/9/737.full.pdf

Other pesticides for ants

There are several commercial pesticides on the market for controlling ants. They may be sprays, powders or baits.  If you follow the label directions, they are as safe as the home or commercial remedies with boric acid.  Active ingredients can contain imiprothrin and cypermethrin, Indoxacarb, hydramethylnon, and orange peel extract among other things.  Read labels carefully, some products can’t be used inside or near food or food crops. 

Carpenter ants and fire ants, possibly crazy ants may require professional exterminators for best results.  They have access to chemicals and methods homeowners do not.