Tree Body of Palos Park
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Carpenter Ants and Trees 

My neighbors have worried from time to time about seeing large, half inch long, black carpenter ants on their trees. Because Palos Park is a former woodland, there are a lot of decaying stumps and rotting roots that attract Carpenter Ants. These are perfect sites for a nest. These ants live in colonies made up of a “queen,” males, workers, eggs, and pupae. The site of the colony can be discovered by the discarded wood chips (frass) piled on the ground near the entrance to the nest. The colony supports a large home nest, normally out of doors, plus several satellite nests .When destroying a nest, one must hunt out the satellite nests and destroy them also, or the ants will persist. 

The ants, associated with dead and rotting wood, do not eat the wood and do not cause the rot. They will not kill your tree. They just prefer the soft moist rotten wood in which to build their nurseries. Indoors, they seek out areas around plumbing and roof leaks. Out of doors, they seek rotting stumps and roots, decaying trees, and firewood. Carpenter Ants eat dead and living insects, the honey dew emitted by aphids, juices, ripe fruit, sugar and sweets, and scraps of food. Generally, when you see a single ant, it is a scout foraging for food. When he finds food, he will leave a pheromone scent trail back to the nest. 

Up to a point, the ants have a positive effect on the environment, in that, as a scavenger, they reprocess or clean up rotting wood. On the other hand, when their tunnels put a strain on the tree’s water conducting capacity and when the tunnels weaken the tree’s structure and the tree becomes a hazard tree, then ants become unwanted pests. 

If one is to get rid of the ants, it is essential to destroy both the home and satellite nests. Aside from finding and destroying the nests, one can trim trees back five feet from any building structure to eliminate pathways into the house. One can eliminate stumps, cover and store firewood away from the house and off the ground, and repair roof and plumbing leaks. Proper food storage and sanitation can reduce ants. One should wash areas that have been used by foraging ants in order to get rid of the pheromone scent trail. 

Every year there are fewer and fewer chemical products allowed to be used by the non licensed homeowner. A few will be available at the hardware or garden center. Read the directions carefully. Boric acid is one material that is still available, It will kill foraging ants but it will not be carried back to the nest. Liquid formulations are also available such as Deltamethrin, Permethrin, Pyrethrin and Tralomethrin. Aerosol sprays do not give long lasting ant control. Bait cups do not work on carpenter ants because they have such a wide diet. But, if you must, use sugary or honey based bait. If you see large amounts of ants indoors (twelve or more in one day) and you suspect a heavy infestation , call a professional exterminator. They are licensed to use stronger, longer-lasting pesticides not available to the general public.