Termites are destructive pests that can cause extensive damage to homes and structures. Understanding their dietary preferences is important for preventing infestations. These insects primarily seek out materials containing cellulose, a complex carbohydrate found in plant matter.
The Primary Food Source: Cellulose-Rich Materials
Termites depend on cellulose for their nutrition. They consume a wide range of materials rich in this substance. The most recognized food source for termites is wood, including structural timbers within homes, floorboards, wooden fences, and outdoor elements like dead trees, stumps, and firewood.
Beyond solid wood, termites also readily consume various paper products. These include books, cardboard boxes, newspapers, and important documents. Natural fabrics like cotton, linen, and rayon can serve as a food source for these insects. Termites are able to digest cellulose through a symbiotic relationship with protozoa and bacteria residing in their gut, which produce enzymes that break down the complex sugars into simpler, digestible forms.
Beyond Typical Wood: Other Vulnerable Materials
Termites can damage materials less commonly associated with their diet, often due to hidden cellulose or tunneling. Drywall, a common building material, is susceptible because of its paper backing, which termites readily consume. While the gypsum core has no nutritional value, the paper layers provide food.
Certain types of insulation can also be vulnerable. Foam insulation, while not a food source, can be tunneled through by termites to create pathways or access other food sources. Some carpet types can also be consumed. Termites may also tunnel through soft plastics, such as PVC pipes or electrical wiring insulation, not for food, but to create protected passages to cellulose-rich materials. Though they prefer decaying wood, some termite species can damage the roots or trunks of living trees and shrubs.
Factors Attracting Termites to Food Sources
Several environmental and material conditions make certain cellulose sources more appealing or accessible to termites. Moisture is a significant attractant for subterranean termites, as they require high humidity and water. Leaky pipes, poor drainage, and damp soil near building foundations create ideal conditions for termite activity.
Wood that is already damp or decaying is easier for termites to penetrate and consume. Direct contact between wood and soil provides an easy entry point for subterranean termites. Cracks in foundations, gaps around utility lines, and unsealed expansion joints offer hidden pathways for termites to enter buildings. While all cellulose is food, some wood species possess natural deterrents or higher density (e.g., redwood heartwood, cedar heartwood) that make them more resistant, though no wood is entirely immune.
Materials Termites Avoid or Cannot Consume
Certain materials do not serve as food sources for termites or are difficult for them to penetrate. Inorganic materials such as concrete, stone, metal, and glass are not consumed by termites. However, termites can still exploit small cracks or gaps in these materials to gain access to cellulose-containing elements within a structure.
Wood that has been specifically treated with insecticides, pressure-treated wood, is designed to be unpalatable and toxic to termites. While highly effective, the protection is not absolute if the treatment is compromised or if termites find untreated sections, such as cut ends. Hard, dense plastics or synthetic materials are not consumed by termites, though softer plastics can be damaged during tunneling activities as termites search for food.