Termites not only eat wood, but also things like books, paper, and insulation.
They can also chew through concrete and thin metals and cause serious damage to your house.
But there are certain types of wood that are termite resistant.
In this short guide, you’ll find out what types of wood termites don’t eat and why.
You can use those wood to make your furniture, structural lumber, and floor impervious to termite invasion.
But before that let’s find out why termites eat wood.
Why Termites Eat Wood?
Termites need cellulose to survive. Wood and products made from wood, like paper, wallpaper, and cardboards have plenty of cellulose.
Fabrics made from pure cotton also contain cellulose. So, termites eat cotton clothes too.
Termites’ digestion system is different from other insects. It contains protozoa and bacteria that break down cellulose to give them energy.
But the worst part is that termites are voracious eaters.
And they breed fast too.
So, termite infestations spike up pretty quickly unless you take measures at the early stages.
When their numbers increase, these pests will eat wood from the inside, turning them hollow.
Termites can cause disaster to your home by putting the structural integrity of your home at risk.
Smart homeowners don’t let this happen.
They not only do regular pest inspection of their home but also use the types of wood that termites don’t eat.
7 Termite-Resistant Woods
- Teak wood
- Redwood
- Cypress wood
- Heartwood of cedar wood
- Pressure-treated wood
- Processed bamboo
- OSB
So, why termites keep away from these wood types? Let’s find it out.
Teak Wood
Teak wood tops the list of wood that termites don’t eat.
In fact, research has showed that teak is even deadly for termites.
In a controlled environment, termites that fed on teak wood showed 75% mortality rate compared to termites that were left unfed.
Termites can chew a bit on the sap, or on the outer layer, of teak wood.
But the heartwood of teak is really solid and termites can’t damage it.
Also, teak wood contain natural oils that protect them from termites, molds, and moisture.
Redwood
After teak, redwood is the second best termite resistant wood.
It’s dark wood. And the natural chemical, which is known as tannin, that exists in redwood make it both termite and fire resistant.
Also, redwood has few pores and less sap that makes it hard for termites to chew on them.
Redwood is one of the best structural lumber that you can use in your home.
It also works against damaging termites like drywood termites that attack the joists, beams, roofs, and shingles of your home.
Redwood is also resistant to moisture. So, it can’t decay.
And it’s also mold-resistant.
Cypress Wood
Cypress wood is a hardwood which is very dense. So, it’s impossible for termites to chew through the wood.
It’s for this reason cypress heartwood make good termite resistant mulch beds.
But the softwood cypress, which is another type of cypress wood, is not naturally resistant to termites.
Softwood cypress is often treated with chemicals to make them termite resistant.
Cedar Wood
Termites don’t eat cedar. But termites will feed on the outer layers of the cedar wood.
Cedar wood contains natural chemicals, allelochemicals, in them.
That makes cedar wood repelling to termites.
And this allelochemicals is present at the core, which is known as heartwood, of the cedarwood.
So, termites can feed on the outer layers of cedar wood, but can’t reach it’s core.
Using cedar wood as the structural lumber in your house or as building materials will make your home termite-deterrent.
But cedar wood is expensive than your average wood.
Pressure-Treated Wood
Pressure-treated wood are made from softwood by treating and mixing them with chemical preservatives.
The most common chemical that manufacturers of pressure-treated wood use is chromate-copper arsenate (CCA).
This chemical protects the pressure-treated wood against decay and from insects like termites and ants.
Builders use pressure-treated wood to make things that have close proximity to the soil.
So, floors, decks, fence posts, stairs, and basement walls are made from pressure treated wood.
But there are two drawbacks of pressure treated wood.
First, pressure treated wood used in home building materials have an approximate lifespan of only 10 years.
So, it’s not a set it and forget it type of thing if you’re using it.
Over time, the chemicals will wear off the wood and make it vulnerable to termites like subterranean termites that attack from underground.
Second, pressure treated wood contain softwood like pine wood. And softwood draw termites like magnet.
So, if you’re not replacing the pressure-treated wood before it’s lifespan is over, you’re making your home vulnerable to termite infestation!
Processed Bamboo
Termites can eat bamboo. But they won’t eat bamboo processed with chemicals.
Many people believe that termites won’t eat natural bamboo because bamboo is grass.
Well, bamboo is 73.5% cellulose. And cellulose forms the major part of termite’s diet.
Processed bamboo work in the same way as pressure treated wood.
Most manufacturers use borate to process natural bamboo to protect it from termites.
Borate removes the sap and cellulose from the bamboo.
Termites can detect borate, or boric acid, present in the bamboo.
And boric acid is lethal for termites.
If termites consume borate, then it’ll kill the protozoa in their guts which helps them to break down cellulose.
In short, borate destroys termite’s digestive system.
OSB (Oriented Standard Board)
OSB is termite resistant. It’s made from wood strands of primarily aspen and poplar trees.
The wood strands of these trees are mixed with waterproof resin and adhesives to form thick mats.
These mats are then pressurized chemicals and heat.
This entire process makes OSB impervious to termites attack.
That’s why OSB is used in subfloors in many homes.
It makes the floors robust and it also deter termites from invading the house from underneath the soil.
What Types Of Wood Termites Eat?
Wood rich in cellulose and with softer heartwood will always attract termites.
So, the following types of wood termites will eat –
- Softwoods like pine and fir
- Untreated hardwoods like oak, hickory, and maple
- Sheetrock and drywall
- Plywood
- Particle board
Point to note here is that some types of wood like Peruvian walnut have some degree of termite resistance.
But Peruvian walnut can’t hold against termites for long.
Research has shown that termites, despite showing 16.4% of mortality rate when exposed to Peruvian Walnut wood, damaged it at a rate similar to birch and oak.
Untreated softwoods in their natural form are not termite resistant.
But when softwood is mixed with chemicals like borate, they can become termite resistant too.
An example of treated softwood which is termite resistant is pressure-treated wood.
Signs Of Termites In Wood By Termite Species
There are three common types of termites species that attack homes.
And all three of them have different signs.
Subterranean Termites
Subterranean termites attack homes from the underground.
They’ll dig tunnels on your home’s walls to access the wood in your home.
So, hardwood floors, furniture, and fences are their prime targets.
These termites have got strong mandibles or jaws that they can use to chew through the cement to reach their food source.
Signs of subterranean termites in infested wood are mud tubes and fecal pellets.
Pest controllers use termite granules, in the home’s soil bordering the foundation walls.
The granules act as a chemical barrier that deter subterranean termites from attacking the home from underground.
Subterranean termites’ close cousins, the Formosan termites, are more destructive than them.
They’re bigger than the subterranean termites and cause more damage to your home.
Drywood Termites
Drywood termites invade homes by flying inside the home as swarmers.
These swarming termites are termites with wings. These winged termites are also known as alates or reproductives.
They leave their previous colonies to find a new home.
And when drywood termites enter your home, they will mate, lose their wings, and drill themselves into the wooden structures of your house to start a colony.
Drywood termites are hard to detect.
Some of the signs that can tell you that there has been a drywood termite invasion are broken termite wings on the floor and tiny holes on the structural joist and beams.
Dampwood Termites
Dampwood termites are least likely to invade homes.
They feed on damp and decaying wood blocks in your yard and on things like rotting tree stumps.
But dampwood termites can sneak inside the house if they can detect decaying wood pieces inside.
Conclusion
Termites don’t eat wood that are chemically treated to deter termites or have natural chemicals that make the wood resistant to termites.
Teak, redwood, cypress, and cedar wood are naturally resistant to termites.
But termites can feed on their surfaces. And they won’t reach the heartwood or core of these woods to damage them.
Chemically treated wood types like OSB, processed bamboo, and pressure treated wood are also termite resistant.
If you’re seeing signs of termites in your home, then hire a professional pest control specialist for a termite inspection.
Dr. Thomas Orbert is a PhD in Entomology with extensive research experience in ectoparasites and microbials. He has also worked in the spaces of ecology conservation and has multiple years of experience in field research and scientific publishing.