Weeds And Pests

How to Kill Ants

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"How to Kill Ants"
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People are often acquainted with swarming ants, and wage a personal war against them when they are found within the house or even in the yard. Killing them can be uppermost in their minds. It is best to keep in mind whether the intention is to kill ants, or to kill an ant nest.

Ants can be a huge problem; in the yard, in the home and in the garden. Some, like the harvester ant, are mostly just annoying pests, and they are harmless. Others like the carpenter ant and the fire ant are much more serious. Carpenter ants can destroy the wood a house is made of, and fire ants can cause a painful, and at times deadly, sting or bite.


It is important to understand that what works to kill ants quite well with one species doesn't necessarily work with another. Most of the common pest ants, though, have a few traits in general that make it much easier to control them.

For instance, all three kinds of ants mentioned have a distinct liking for things that are sweet. This leads to a couple fairly easy methods of killing them.

One of the easiest ways is to mix baker's yeast with molasses in a bottle cap and to place it where the ants can get to it. It should be put where pets can get to it, however, as it can also be harmful for the pets.

The yeast and the sugars in the molasses combine and begin to ferment. However, the reaction is slow because of the properties of molasses. The ants ingest this and take it back to the hive or hill. Usually, it ends up being fed to the queen and other members of the nest.

Here's the thing, though: Fermentation of sugar, in this case that contained in the molasses, results in the creation and expulsion of carbon dioxide. This reaction between yeast and sugar is what makes bread rise, and it is what makes a person burp when they drink beer or pop too quickly. Ants can't burp. So the buildup of the carbon dioxide kills them. If the queen is killed, the nest dies. (Unlike bees, ants can't just feed special food to larvae to produce new queens.)


Some people believe that they can kill an ant nest by pouring boiling water over the nest. Granted, this will kill exposed ants. However, the nests are often extensive in depth and breadth. Since water cools rapidly when it comes into contact with a substance such as soil, most of the ants survive and it is unlikely that the hot water will reach the protected queen. Many people try it and can be dismayed when the nest continues to thrive.

Gasoline or diesel will also kill ants quickly. The same problem exists, though. Most ants survive and the queen is seldom touched. Using solvents like these have other unwanted effects. They also kill nearby vegetation and can end up in the water supply, tainting the water people drink. Large amounts of these fluids can have a long lasting and detrimental affect on a lot more than the ants.


There are many insecticides on the market that will kill ants. How well they work is a matter of opinion, and they have the same problems as mentioned. They can end up in the water supply and poison anyone drinking the water, they leave residues that can last for years and they can kill helpful insects as well as ants, and they can harm other creatures as well.

The queen

The key to wiping out the ants is to kill the queen. Once the queen is dead, the colony can no longer survive, and it will die out. Without the egg factory, the ant nest is doomed. This is true of both ground dwelling ants and those that take up residence in the home. The reason the molasses and yeast works is because it gets to the queen. When she is dead, the rest in that nest will soon follow. The lifetime of a queen can often be measured in years, while the lifetime of the workers is more often measured in weeks or months.

It should be remembered that killing a few ants, or even deterring them, is much different than killing the source, the nest. Even household ammonia will kill an ant, however few people want to use it to kill all the ants in a nest. Some queen ants are capable of laying 10,000 eggs a year. A spray bottle with ammonia isn't going to make much of a dent in the population. To stop an infestation, the queen needs to be irradicated.

Killing ants isn't a trick, though it also isn't easy for long term results. Many things will kill them, including commercial sprays. However if you want to kill a nest, the goal is to get to the queen. Spraying poisons isn't an good option. Too many other animals and plants will suffer. It is perhaps better to think of deterring and discouraging them rather than about how to kill them, though in some instances, the latter is preferable to the former.


Oregon Institute of Technology
Chiloquin High School
Arches National Park, Utah
National Geographic Explorer

More about this author: Rex Trulove

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