The question of whether moths consume cardboard often arises from finding damaged boxes in storage areas. Moths do not typically use cardboard as a primary food source, but their larvae can chew through it to reach a more desirable material stored inside. Damage seen on the cardboard itself is often caused by other types of pests entirely. Understanding the difference between Clothes Moths and Pantry Moths is key, as only their larval stage is responsible for causing damage.
The Truth About Moth Diets
Moth larvae possess highly specific dietary requirements that exclude the primary components of cardboard. Clothes moth larvae, such as Tineola bisselliella, require keratin for development. Keratin is a fibrous protein found in natural animal fibers like wool, silk, feathers, and hair. Larvae have evolved a unique ability to digest this protein, often assisted by specialized gut bacteria.
Pantry moth larvae, including the Indian Meal Moth (Plodia interpunctella), have a completely different diet centered on dried food products. These pests feed on stored grains, cereals, dried fruits, flour, nuts, and pet food. Cardboard is primarily made of cellulose, which is not a digestible source of nutrition for either clothes or pantry moth larvae.
While cardboard is not nutritious, the larvae of both species chew through packaging as an obstacle to access the preferred food source inside. The adult moths, which are often seen flying, are focused only on reproduction and generally do not feed at all.
Identifying the True Cardboard Eaters
If holes or signs of feeding are visible on the cardboard box itself, the culprit is likely not a moth but a pest that consumes cellulose or starch. Silverfish, which are small, wingless insects, are particularly attracted to the starches and adhesives used in cardboard construction. They feed by rasping the surface, leaving behind irregular, notched holes, frayed edges, or a scraped, dull appearance.
Cockroaches are another common cardboard pest, often attracted to the starch-based glue that binds the layers of corrugated boxes. They will also chew on the cardboard itself, using the material as a nesting site in dark, sheltered areas.
Certain beetles, such as the Drugstore Beetle and Cigarette Beetle, bore clean, small holes through packaging to reach dried food products. Termites are significant cardboard feeders because the material is rich in cellulose, their primary food source. Booklice, or Psocids, may also be found on cardboard, feeding on mold or mildew that grows on damp boxes. Since many of these pests thrive in the same dark, humid conditions as moths, their presence is often mistaken for a moth problem.
Why Cardboard Attracts Moths
Cardboard boxes are attractive to moths and other pests not for nutrition, but because they provide a near-ideal habitat. The corrugated structure creates multiple layers of fluting and channels, offering a warm, hidden, and insulated shelter. These dark, undisturbed spaces are perfect for adult moths to lay eggs and for larvae to hide while developing.
Cardboard is highly absorbent, soaking up moisture and food odors from the environment. This absorbed humidity makes the box environment appealing to pests, especially when stored in basements or garages. Crucially, boxes typically store items moths want to eat, such as woolen garments or bags of grain. The box thus serves as a secure container for the food source, providing camouflage and protection for developing larvae.
Protecting Stored Items from Infestation
Protecting items from infestation requires eliminating both the food source and the attractive habitat. Before storing natural fiber items, such as wool or fur, they should be thoroughly cleaned, as oils and perspiration attract clothes moth larvae. Dried food products should also be inspected for any signs of pest activity before being placed into long-term storage.
The most effective action is to replace cardboard boxes with sealed containers made of hard plastic or metal. These materials are impenetrable to chewing pests and prevent the absorption of moisture and odors that attract insects. Ensure that plastic bins have tight-fitting or lockable lids to prevent pests from squeezing through small gaps.
Controlling the storage environment is also important for prevention, as moths and silverfish prefer high humidity and stable temperatures. Monitoring the area with pheromone traps can help detect the presence of adult moths before an infestation becomes established. Regularly inspecting and rotating stored items disrupts the dark, quiet conditions pests rely on to multiply unnoticed.