Controlling Ants Outdoors

There are two ways to approach controlling ants:

• Decide to do nothing. Ants are critical detrivores in their eco-system. They help break down dead and dying plant material, eat soft-bodied pest insects and aerate the soil. (Click here for more information on the importance of ants) So if they are not bothering humans or your favorite 4-legger, it may be best to leave the ants alone.

• Control them efficiently and safely by understanding the behavior and social structure of the species of ant you are dealing with. 

Here are some general rules for controlling a colony of ants: 

Take Out the Queen and Kill the Colony. 

Entomopathogenic* beneficial nematodes can be used to parasitize and kill the queen. The species, Heterorhabditis bacteriaphora, can be applied to the ant nest and they will seek out and kill the queen through the process of parasitizing and injecting their bacteria into the queen. Nematodes must be applied directly to the ant mounds so that they can reach the queen. 

Sharing Doesn’t Necessarily Mean Caring.
Because the ant social structure means that food will be brought into the nest and shared, we can take advantage of this behavior to achieve control. 

Many species of ants are attracted to sugar, so the bait traps that use a sweet, syrupy liquid laced with borax or boric acid are very effective both for indoor and outdoor control. For best results, it is important to place these traps along the trails that the ants are travelling. The worker ants will take bits of the sugary liquid back to the nest to share and expand the deadly effects of the borax or boric acid. The content of these traps is not enough to cause harm to your 4-leggers but it is best to keep the traps out of their reach anyway. 

Much like bees and humans, ants live complex lives. They are ubiquitous to the planet and some do good while others cause harm. Although some of their behaviors are consistent from one species to another, there are unique behaviors by many ants. This can make controlling for them a complicated matter. However, proper identification of the species will help save time and money in treating them. 

Weird Facts About Ants:

Fire Ants can have multiple queens making control more difficult and the use of beneficial nematodes less successful. Organic controls include drenching their mounds with orange oil based Orange Guard Fire Ant Control and surrounding the mounds with Diatomaceous Earth. As they attempt to escape the Orange Guard, they pick up the DE and that desiccates their exoskeletons.

Harvester Ants build their nests upside down – with larger chambers closer to the surface and small and smaller chambers deeper in the nest. They are stinging red ants and are often confused with fire ants. However, their behavior is not like fire ants and their sting is not as severe. They can be controlled with nematodes and bait traps. 

Leafcutter Ants – This is a group of 47 ant species that form large and complex societies. Their social structures are second only to humans. Their nests can span and radiate out to 6,400 square ft. Large nests can contain 8,000,000 individual ants. You can control them by using nematodes and DE at the mounds. You can also spray their target plants with a botanical oil. Or try pasting Stiky Stuff around the base or trunk of the plants that they are harvesting leaves from. 

*Entomopathogenic nematodes – A group of nematodes that cause death to pest insects. The word entomopathogenic refers to insect and pathogen (causing disease). These nematodes live as a parasite inside the host insect and they infect their host with a bacterial disease. Once the insect is infected, the nematodes reproduce multiple generations.  

- Contributed by Deb at ARBICO Organics