Carpenter ants do not eat wood. Despite their reputation for destroying wooden structures, their actual diet consists of sweet liquids (especially honeydew from aphids), dead insects, and other protein and sugar sources they find outdoors or inside your home. The wood they tunnel through is purely for nesting, and they kick the shavings out as sawdust piles near their entry points.
Their Primary Food: Honeydew and Insects
In natural outdoor settings, carpenter ants have two main food categories: sweets and protein. Their single biggest food source is honeydew, a sugary liquid produced by aphids and scale insects that feed on plant sap. Carpenter ants actively tend and protect these aphid colonies the way a rancher tends livestock, harvesting the honeydew the aphids excrete.
For protein, carpenter ants hunt and scavenge other insects. They’re effective predators of soft-bodied larvae, including wood-boring beetle grubs. They also feed on dead insects they encounter during foraging. This combination of sugar for energy and protein for colony growth covers most of their nutritional needs in the wild.
Why They Don’t Eat Wood
Carpenter ants lack the gut microbes needed to digest cellulose, the tough fiber that makes up wood. Termites have those microbes; carpenter ants don’t. When carpenter ants excavate galleries inside a log, a wall stud, or a deck post, they’re carving out living space, not eating a meal. The telltale sign is the frass they leave behind: small piles of fine, sawdust-like shavings pushed out of the nest as excavation progresses.
This distinction matters if you’re trying to identify a pest problem. Termite damage leaves mud tubes and hollowed wood with no visible debris. Carpenter ant damage produces clean, smooth galleries and neat piles of wood shavings, often mixed with dead insect parts, near cracks or openings in the wood.
What Attracts Them Indoors
Inside a home, carpenter ants target the same two categories: sugar and protein. Sweet liquids are their strongest draw. Spilled juice, honey, syrup, soda residue around sinks, and pet food left out overnight all qualify. They’ll also go after grease, meat scraps, and crumbs in pantries or on countertops.
Workers forage primarily between sunset and midnight during spring and summer. Only a small fraction of the colony is out searching for food at any given time, so spotting a handful of ants in your kitchen likely means many more are back at the nest. Those workers can travel surprisingly far: up to 100 yards from the nest to reach a food source, which means the colony causing problems in your kitchen may not even be inside your house.
How They Share Food Inside the Colony
Carpenter ants don’t chew and swallow food the way you might picture. Workers collect liquid food in a second, expandable stomach (sometimes called a “social stomach”) and carry it back to the nest. There, they regurgitate it mouth-to-mouth to other workers, the queen, and developing larvae in a process called trophallaxis.
This communal feeding does more than distribute calories. Research on Florida carpenter ants found that the liquid passed between nestmates contains a rich cocktail of growth-regulating proteins, hormones, and chemical signals, not just digested food. One key ingredient is a hormone that controls insect development. When scientists added extra amounts of this hormone to the food supply of larvae-rearing ants, larvae were twice as likely to survive to adulthood. In effect, nurse ants aren’t just feeding the young; they’re dosing them with growth-promoting compounds that shape the next generation of the colony. Researchers have compared this private chemical channel to the role of milk in mammals.
The trophallactic fluid also carries scent cues that give every member of the colony a shared odor, allowing ants to tell family from intruders. So each mouth-to-mouth exchange simultaneously delivers nutrition, developmental instructions, and identity markers.
Seasonal Shifts in Diet
Carpenter ant food preferences aren’t fixed year-round. Colonies need different nutrients at different times. In spring, when the queen is laying eggs and larvae are growing rapidly, workers seek out more protein, hunting insects and scavenging animal matter. As the season progresses and the colony’s energy demands shift toward maintaining adult workers and fueling foraging, sugar sources become the priority.
This seasonal swing is why pest control experts recommend offering multiple types of bait at once, giving ants a choice between sugar-based and protein-based options. A sugar bait that works well in July may be ignored in April if the colony is in protein-seeking mode. Baiting is most effective in late winter and early spring, when colony populations are still small and beginning to ramp up.
Reducing Food Sources Around Your Home
Because carpenter ants forage for the same sugars and proteins found in any kitchen, the most practical step is eliminating easy meals. Clean up sweet residues around sinks and countertops, store sugary items in sealed containers, and avoid leaving pet food out overnight. Pay attention to sticky spots: a thin film of dried juice in a crack near the sink is exactly the kind of target workers seek out on their nighttime rounds.
Outdoors, aphid colonies on shrubs and trees near your foundation are essentially a carpenter ant buffet. Managing those aphid populations, or at least being aware of heavy infestations on plants close to the house, can reduce the incentive for carpenter ants to establish satellite nests nearby. Firewood stacked against exterior walls and tree branches touching the roof also create convenient bridges between outdoor food sources and indoor nesting opportunities.