Subterranean termites are common pests found globally, known for their destructive capabilities. They can cause substantial damage to homes and other structures, often before their presence is even noticed. Understanding their dietary habits is important for comprehending the extent of their impact and developing effective prevention strategies. These insects, while small, play a significant role in ecosystems by breaking down organic matter.
The Primary Dietary Component
The fundamental component of the subterranean termite diet is cellulose. This complex carbohydrate forms the primary structural material in plant cell walls. It is an abundant organic compound found throughout nature, providing termites with necessary nutrients for survival.
Termites rely on breaking down this complex material into simpler sugars to obtain energy. Without the ability to digest cellulose, they cannot sustain themselves. Any material containing cellulose is thus a potential food source for these insects.
Specific Materials They Consume
Subterranean termites consume various forms of cellulose, extending beyond just wood. While wood is a primary target, many other household items are also at risk. They infest structural timbers, dead trees, and fallen branches, often preferring softwoods like pine, spruce, and redwood due to easier digestion.
Termites also consume paper products, including books, cardboard, and other paper-based packaging materials. Cotton fabrics and some plant-based composite materials are also susceptible to their feeding. They can damage insulation containing cellulose. Termites often prefer moist or decaying wood, as it is softer and easier to consume. In buildings, they typically feed on wood in contact with the ground, such as support beams and flooring, but can build mud tubes to access higher levels.
How Termites Digest Their Food
Subterranean termites possess a unique biological process to break down cellulose. They cannot digest cellulose directly on their own. Instead, they depend on a symbiotic relationship with microorganisms, primarily protozoa and bacteria, residing in their hindguts. These microbes produce enzymes essential for breaking down cellulose into usable sugars.
Protozoa, which are single-celled organisms, are a major source of cellulose hydrolysis, fermenting products into acetate, which the termite uses for energy. Bacteria within the protozoa further contribute by producing cellulase enzymes. This mutualistic relationship benefits both termites, who gain nutrition, and microorganisms, who receive a protected environment and constant food supply.
Materials Termites Typically Avoid
Subterranean termites generally avoid materials that do not contain cellulose. They do not consume concrete, metal, or most plastics, as these offer no nutritional value. While termites cannot eat through concrete, they exploit tiny cracks, gaps, or expansion joints in foundations to gain entry and reach cellulose-containing materials. Similarly, they may chew through thin plastic barriers or insulation to access food sources, even without digesting the plastic.
Treated wood is also avoided because it is infused with chemical preservatives that make cellulose indigestible or toxic. However, treated wood is not entirely immune; termites may still infest it if treatment breaks down over time, if there are untreated areas like cut ends, or if no other wood is available. Termites can also build shelter tubes over treated wood to reach untreated wood beyond it.