4 Things to Know about Carpenter Ants

Most people recognize carpenter ants due to their large size (major workers are around ½ inch long) and their dark black color. However, there are minor workers that are only ¼ inch long and there are species that are red and black. Definitive ID can be made with a microscope by checking to make sure the thorax is evenly rounded and there is only one node between the thorax and abdomen. Here are some other things to know about these big ol’ ants.

carpenter ant

  1. Carpenter ants do not eat wood

Unlike termites, which do actually consume and digest wood, carpenter ants are merely living in it. They hollow out portions of dead wood in trees or lumber in structures in order to have a home for their colony. In some situations, they may utilize wood that is damp from natural decay or a leak in the house, but they can move into drier wood around them as the colony expands. Carpenter ants actually eat sugary items like insect honeydew, syrup, and honey as well as protein based foods like live and dead insects.

Black Carpenter Ant Nest,Tree Trunk, JAK600 (2)
Carpenter ant galleries inside of a tree. They are not eating the wood, just digging out a house for the family!
  1. Why do some carpenter ants have wings?

Carpenter ant colonies produce new males and queens in order to have a mating flight to produce new colonies. These queens and males have wings so they can fly around and mate with one another. After mating the female queen will fly away and search for a new nesting site. When she lands and begins searching her wings will fall off. When people see winged ants they often mistake them for swarming termites. If you take a magnifying glass you look at the insect’s wings to determine if you are looking at an ant or a termite. Ants have four wings, two large top ones and two smaller noticeably ones on the bottom. Termites also have four wings but they are all equal size.

ant v term
Ant or termite? Look to the wings and the waist to deduce the identity of your pest.
  1. Carpenter ants leave behind symptoms of their presence

Most people notice the ants themselves but carpenter ants can leave other indicators that they are present. One main sign of an active nest is a pile of sawdust like material under a tree or near the home. The sawdust is usually coarse and may have pieces of dead ants and other insects in it. These piles can simply be waste wood or they may be the funeral/garbage pile for the colony. Active carpenter ant colonies can also make a dry, rustling sound that people often describe as saran wrap being crinkled in the wall. This sound and the sawdust piles help pest management professional to diagnose, locate, and eliminate carpenter ant nests.

carpenter ant frass JAK501 (2)
Wood shavings, dead ants, pieces of insects, and other debris in a carpenter ant refuse pile.
  1. What should you do if you find carpenter ants?

Due to their nests being in hard to reach spots in attics, ceilings, and wall voids and their general disinterest in ant baits, it is usually best to hire a pest control professional to deal with carpenter ants. They will typically sound for the nest and then drill small (about 1/8 inch) holes and apply an insecticidal dust into the nest area. Maxforce Carpenter Ant Bait gel is another option, but due to the varied diet of these ants it may not be successful at intervals in the year.

All photos courtesy of James Kalisch; University of Nebraska-Lincoln Entomology Department

Jonathan Larson
Nebraska Extension Entomology Educator at Nebraska Extension

Jonathan Larson is focused on providing Nebraskans with information regarding insects that may impact their lives. He can help to identify any insect or arachnid pest you find in your home or landscape and provide control tips that are environmentally and economically sustainable.


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