Updated
Most homeowners never think about termites until they find the damage. By then the colony has been feeding for months, sometimes years. Not every board in your house is equally appealing to them. Some wood practically invites them in, and some makes them turn around. Knowing the difference is useful anywhere, but it matters in a particular way in Western Pennsylvania, where one species does nearly all the damage.
What types of wood are termites most attracted to?
Termites eat cellulose, which is in every kind of wood. They still have clear favorites. Softwoods like pine, spruce and fir sit at the top of the list. In laboratory feeding tests, southern yellow pine is the standard wood researchers use as termite bait because it is so readily eaten. Softwoods are lighter, easier to chew and tend to hold more moisture.
A common assumption is that termites only go after old, rotting wood. Decaying wood is more attractive to them, but they will feed on fresh softwood framing in a brand new house when the conditions suit them. Age is not the deciding factor. Moisture and access are.
Softwood framing is the most common building material in Pittsburgh homes, and it is also the easiest wood for termites to chew through.
The only termite that really matters in Pittsburgh
Nationally, homeowners deal with several termite species. In Pennsylvania the picture is much simpler. According to Penn State Extension, the eastern subterranean termite is found throughout the state and is the species that damages structural timbers in buildings here.
That has a practical consequence for your house. Subterranean termites nest in the soil and come up into a structure from below. They are drawn to wood that touches or sits near the ground: deck supports, fence posts, basement framing, firewood stacked against the foundation, and sill plates close to grade. Drywood termites, the ones that infest furniture and hardwood floors without any soil contact, are not established in Pennsylvania. They can arrive inside imported furniture or crates, but they are not what is eating Pittsburgh houses.
So when you read national advice about termite-resistant wood, read it with that in mind. In this area the question is almost always where wood meets soil and moisture, not what your coffee table is made of. Our termite inspection and treatment service is built around that soil-to-structure path.
What wood do termites avoid?
Some woods carry natural oils, resins and compounds that termites find unappealing or outright toxic. Teak is the best known, and it rates among the most resistant woods in laboratory testing.
Redwood heartwood holds up well too, thanks to tannins and a tight grain that resists moisture. The heartwood of cedar, old growth cypress and mahogany also rates well, helped by dense grain and natural oils. Sapwood, the paler outer wood, has little of that protection.
No wood is termite-proof. Even the most resistant species can be attacked when it stays wet long enough.
Termites eat the soft spring growth first and leave the harder grain behind, which is why damaged wood often looks layered.
Termite resistance by wood type
| Wood type | Termite resistance | Why |
|---|---|---|
| Teak | Very high | Natural oils that are toxic to termites |
| Redwood heartwood | High | Tannins and tight grain |
| Cedar | Moderate to high | Aromatic oils |
| Cypress | Moderate to high | Dense grain and natural compounds |
| Pressure treated lumber rated for ground contact | High | Preservative forced into the wood, though cut ends and drilled holes are less protected |
| Pine | Very low | Soft and porous, holds moisture |
| Spruce | Very low | Soft and easily eaten |
Moisture matters more than the wood itself
Wood type matters. Moisture matters more. Termites need water, and damp wood gives them food and hydration in the same place. A small roof leak, a downspout dumping against the foundation, poor grading or a humid crawl space can turn safe wood into a target.
Pressure treated lumber helps, because preservative is forced deep into the wood. The weak points are cut ends, notches and drilled holes, which expose untreated wood unless they are sealed on site, and termites can also build tubes over treated wood to reach untreated framing above it.
This is also why older Pittsburgh houses with stone or block foundations, buried porch posts and basement wood near grade deserve a closer look than newer construction on a poured slab.
Wood in contact with soil beside the house is the classic entry point for subterranean termites.
What termites hate the most
Beyond resistant species, termites dislike dry conditions and certain treated materials. Borate treated wood works because boric acid destroys the gut organisms that let them digest cellulose, so they starve. Composite decking resists them well because its wood fibers are encased in plastic.
The preventive steps are unglamorous and they work:
- Keep firewood and lumber off the ground and away from the foundation
- Fix plumbing and roof leaks promptly
- Make sure gutters and downspouts carry water away from the house
- Remove wood to soil contact wherever you find it
- Keep mulch a few inches back from siding and sill plates
- Ventilate crawl spaces and dry out damp basements
Those steps reduce what attracts termites to a house in the first place.
Household targets people forget
Termites go after anything with cellulose, not just framing. Cardboard stored in a damp basement, mulch piled against the foundation, untreated patio furniture and the paper backing on drywall are all food.
Untreated pine framing is both the most vulnerable common material and one of the most widely used in residential construction, which is a large part of why termite damage is so common. If you are wondering how far it can go, see how fast can termites destroy a house.
A honeycomb pattern inside a board is a sign the colony has been feeding for a long time.
Protecting your home
Choosing resistant wood is a sensible move for exposed projects like decks, posts and raised beds. It is not a defense on its own. The approach that actually holds up combines material choices with moisture control and regular professional inspection, because the early signs of subterranean termite activity happen below the floor and behind finished walls where nobody is looking.
The U.S. Environmental Protection Agency makes the same point: reducing moisture around the structure is one of the most effective things a homeowner can do.
Stewart Termite & Pest Control has been treating termites in Pittsburgh since 1987. If you have found damaged wood, mud tubes or swarmers, or you simply want the house checked, call 412-822-7610 or request an estimate online.
Frequently Asked Questions
What is a termite’s favorite wood?
Soft, damp wood showing early fungal decay. Southern yellow pine and spruce rate highest in feeding studies, and both are common in residential framing.
Are drywood termites a problem in Pittsburgh?
No. The eastern subterranean termite is the species established throughout Pennsylvania. Drywood termites can arrive inside imported furniture or crates, but they are not established here.
Does pressure treated lumber stop termites?
Lumber rated for ground contact resists them well. Cut ends and drilled holes are the weak spots, and termites can build tubes over treated posts to reach untreated framing above, so it is not a substitute for inspection.
Can termites get into a brand new house?
Yes. Fresh softwood framing is perfectly good food. New construction is not protected by age, only by how it was built and how dry it stays.
Is there any wood termites will not eat?
No wood is completely immune. Teak and redwood heartwood resist them well, and borate treated wood and plastic composite decking are poor food, but wood of any kind can be attacked under the right conditions, and termites will tunnel over resistant wood to reach something better.
What is a termite’s worst enemy?
Ants raid termite colonies, and spiders, centipedes and woodpeckers all eat termites. None of that protects a house. A queen lays thousands of eggs and the colony recovers quickly, which is why inspection and treatment are the practical answer.