Ants around cardboard often raise the question of whether they consume the material. Ants do not eat cardboard for sustenance because they lack the digestive enzymes needed to break down cellulose, the primary component of paper products. Their interaction is driven by the material’s secondary properties and the environment it creates, not nutrition. Finding ants on a box means they are either foraging for other substances present on the packaging or seeking a suitable place to establish a colony.
Why Ants Seek Out Cardboard
Ants are frequently drawn to cardboard boxes for specific components used in manufacturing and for residual contaminants left on the surface. The corrugated layers of boxes are often held together with adhesives that contain starches, which are a readily digestible food source for many ant species. These starches, derived from corn or wheat, provide the simple carbohydrates that ants require for energy, effectively making the glue a hidden treat.
Beyond the adhesive, cardboard can absorb food residues, grease, and spilled sugary liquids, transforming the box into a foraging target. An ant scout detects these minute traces of food, laying down a pheromone trail to guide the rest of the colony to the potential meal. This phenomenon is why boxes that have been used to ship groceries, takeout, or food packaging are especially susceptible to ant infestations.
A significant factor attracting ants is the moisture-retaining quality of cardboard, which is important for colony survival. Cardboard readily absorbs water from humidity, leaks, or condensation, providing a convenient and sheltered water source. Since ants require a consistent water supply for hydration and brood development, a damp box in a basement or garage becomes highly desirable habitat.
Cardboard as a Nesting Resource
While ants do not consume the cellulose, they actively seek out cardboard because its structure offers superb conditions for shelter and brood rearing. The layered construction of corrugated cardboard creates numerous voids and air pockets that provide insulation and security. This dark, sheltered environment is ideal for a satellite colony to raise its larvae and pupae away from the main nest.
Certain species, particularly Carpenter Ants from the genus Camponotus, will deliberately damage cardboard to create nesting space. These ants do not ingest the material; instead, they excavate the paper fibers with their mandibles to form smooth, clean galleries within the corrugation. The soft, layered nature of the cardboard is much easier for them to manipulate than solid wood, allowing them to rapidly expand their nest chambers.
The suitability of cardboard as a nesting site increases dramatically when the material is damp or has been compromised by water damage. Moisture softens the material, making excavation easier for the ants and providing the high humidity that developing ant brood requires. A stack of wet boxes provides a perfect, easily customizable location for a carpenter ant colony to establish a satellite nest.
Distinguishing Damage and Prevention
Determining the source of damage in cardboard is an important step, as it helps differentiate between ant activity and more serious pest issues like termites. Ant damage, especially from carpenter ants, is characterized by clean, smooth-walled tunnels and the presence of fine, sawdust-like debris called frass. This frass is the material they kick out of their nest and often contains discarded paper fibers and insect body parts.
Termite damage, in contrast, results from the insects actually eating the cellulose, leaving behind galleries that are generally rough and filled with mud or fecal pellets. Subterranean termites often construct distinctive mud tubes on the exterior of the material to maintain a humid travel environment. Visually inspecting the tunnels for cleanliness and the presence of mud or pellets can help correctly identify the responsible pest.
Implementing preventative measures is the most effective way to keep ants from using cardboard in the home.
Prevention Strategies
- Store boxes in areas with low humidity, using a dehumidifier in basements or garages to keep the air dry.
- Transfer stored items from cardboard into hard plastic containers with tightly sealing lids.
- Promptly dispose of any cardboard stained with food or exposed to water.
- Ensure stored items are clean before packaging to eliminate residual food sources.