We have ants inside and outside of our house. Twice a year, we have flying ants in the basement of our house. In our garden and strawberry patch, we have big aggresive ants that make it difficult to enjoy our strawberries. What is the best way to get rid of the ants in these places? Is is ok to poison them around the strawberries? What about in the house?



First off, ants are relatively difficult to deal with. Treating worker ants (all of the ones you see) with chemicals is basically ineffective in the overall fight against
the colony.  Ants basically have a little ant-reproduction factory under the ground, and they can replace the worker ants as fast as you can spray them.

At the Utah Pest Plant Diagnostic Lab we believe (as do many others) that the control of any insect should begin with proper identification. Most people think that ants are just ants.  That is a very bad assumption; ants are one of the most diverse and abundant groups on the planet.  Different ants eat different things, have one, two or many sizes of workers.  They can have one to many queen ants, can reproduce colonies in various ways, may or may not have mating flights one to multiple times in a year, and much more.

It is really important to know what your ants like to eat. In the nest, ants like to share food with each other. It is this sharing of food that can be used against an
ant colony. Ant baits are slow-acting insecticides that the ants eat, take back to the nest, and then feed to developing ants (larvae), etc.  If you are lucky
the worker, or the larvae, will feed the queen ant(s) and you will have stopped the production of eggs. Over time the colony will go away.  This takes patience,
however, and may not work if the particular ant species will not feed on the on the bait formulation you have selected, or if the queen ants are not affected.

So, you can try an all-purpose ant bait that you can purchase at your local garden store, or you can do it properly and send in a sample for me to identify.  If you do choose to use baits there are a couple things to keep in mind... 1) put the baits along ant trails (the long trails of ants that usually follow foundations, sidewalks etc.). Placing baits randomly in the middle of the yard won't get the job done. 2) Keep the baits away from small children. 3) Do NOT spray worker ants that are feeding on the baits.  They need to be alive to carry the chemical back to the nest.  This is slow acting material so you need to give it time.

Here are the addresses to our website, and directions to submitting a sample to the lab.  The more ants you can send, the better.  And make sure they are in some kind of liquid (rubbing alcohol or nail polish remover preferred).

UPPDL home page:          http://www.utahpests.usu.edu/
Submission Directions:    http://utahpests.usu.edu/uppdl/htm/forms

For your particular situation, these sound like they might be carpenter ants (big ants).  If you have swarming inside your house they might be living in the wall voids, etc. I think that it is very important for you to get these identified as quickly as you can, or have a professional come out and look at your place. In my opinion it would be better to know what species of ant you have before a pest control company comes to survey. Carpenter ants can have multiple satellite colonies throughout your yard and house, so to get rid of those you will really need a professional to locate and treat all of those colonies. I am actually working on a factsheet about carpenter ants that will be uploaded to our Website in about a month or so. Meanwhile you can conduct a google search for "carpenter ants USU" to get to our old factsheet.

In the meantime, I would put out some baits and let the ants start eliminating themselves.

If you have more questions, please send me an email.

Posted on 30 Apr 2008

Ryan Davis
Arthropod Diagnostician, Utah Plant Pest Diagnostic Laboratory

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