Getting rid of termites in trees naturally is possible, but most natural methods work as spot treatments rather than colony eliminators. The key challenge is that termite colonies can number in the hundreds of thousands, and killing the ones you can see rarely wipes out the entire population. That said, several natural approaches can reduce infestations and protect your trees, especially when combined.
Identify What You’re Dealing With First
Before choosing a treatment, figure out whether you have subterranean or drywood termites. Subterranean termites live in the soil and build mud tubes up into trees and structures. They’re the more common and destructive type. Drywood termites nest inside the wood itself and don’t need soil contact. This distinction matters because some natural treatments only work well against one type.
Look for mud tubes running along the trunk, hollowed-out wood, small piles of sawdust-like droppings (called frass) at the base, or sections of bark that sound hollow when tapped. If the tree trunk feels spongy or large sections are already hollowed out, the infestation may be too advanced for DIY methods.
Beneficial Nematodes
Microscopic roundworms called beneficial nematodes are one of the most effective natural options. These parasitic worms burrow into termites, release bacteria that kill the host within 24 to 48 hours, and then reproduce inside the dead insect to seek out more prey. Lab and field studies have shown certain nematode species achieving 95% to 100% termite mortality at proper concentrations.
You can buy beneficial nematodes (look for Steinernema species) online or at garden centers. Mix them with water according to the package directions and apply the solution to the soil around the tree’s base, into visible termite tunnels, and along any mud tubes on the trunk. Apply in the early morning or evening, since nematodes are sensitive to UV light and heat. Keep the treated soil moist for several days after application so the nematodes can move through it. One round of treatment often isn’t enough, so plan to reapply every few weeks during warm months when the soil temperature stays above 60°F.
Boric Acid Solutions
Boric acid is a mineral powder that damages termites’ digestive systems and eventually kills them through dehydration. It works both as a contact killer and a slow-acting poison when termites ingest treated wood. A basic solution calls for mixing one part boric acid with three parts water, then applying it directly to infested areas of the tree, visible tunnels, and exposed wood surfaces.
For better penetration into thicker wood, you can add one to two tablespoons of propylene glycol (a non-toxic antifreeze, not ethylene glycol, which is dangerous to pets and wildlife) per quart of solution. Apply with a spray bottle or paintbrush, focusing on cracks, damaged bark, and any openings where termites enter the wood. Reapply after rain.
There’s an important caution here: boric acid is toxic to plants in anything more than trace amounts. Avoid soaking the soil directly around the tree’s root zone with boric acid solution, and don’t pour leftovers near edible plants. If you need to dispose of extra solution, dilute it heavily and pour it on bare ground away from garden beds.
Orange Oil (d-Limonene)
Orange oil extract contains d-limonene, a compound that dissolves termite exoskeletons on contact. You can buy concentrated orange oil at hardware stores or online, dilute it according to the label, and inject or brush it into termite galleries and holes in the tree.
The catch is that orange oil is strictly a contact killer with very limited residual effect. It kills the termites it touches but does nothing to manage the broader colony. Field studies have confirmed this limitation. It’s better suited for drywood termites (which live in contained pockets within the wood) than for subterranean termites, where the real population lives underground and continuously sends workers up into the tree.
Orange oil is also flammable and mildly acidic, so store it carefully and avoid applying it in extreme heat. It can cause leaf burn if it contacts foliage, particularly on hot days.
Diatomaceous Earth
Food-grade diatomaceous earth is a fine powder made from fossilized algae. The microscopic silica particles absorb the oils and fats from termite exoskeletons, causing them to dehydrate and die. Spread it around the base of the tree, into cracks in the bark, and over any exposed wood where you see termite activity.
The main limitation is coverage. Diatomaceous earth only works where termites physically contact it, and they’ll route around treated areas if they can. It also loses effectiveness when wet, so you’ll need to reapply after rain or watering. Think of it as one layer of defense rather than a standalone solution. Keep in mind that diatomaceous earth is highly toxic to bees and other beneficial insects, so avoid applying it near flowering plants or during times when pollinators are active.
Cardboard Traps
Wet cardboard traps are the simplest method and sometimes recommended as a first step. Moisten sheets of corrugated cardboard and place them near the base of the infested tree. Termites are attracted to the cellulose in cardboard, so they’ll colonize it. After a day or two, remove the cardboard and burn it or seal it in a bag for disposal.
This approach has a serious ceiling, though. It takes only two termites to restart a colony, so unless you capture every last individual (which is virtually impossible), the infestation comes right back. Cardboard traps are best used to monitor activity levels and confirm where termites are active before applying other treatments, not as a primary control method.
Combining Methods for Better Results
No single natural treatment reliably eliminates a full termite colony in a tree. The most effective approach layers several methods together. Start with cardboard traps to locate the most active areas. Apply beneficial nematodes to the surrounding soil to attack the underground colony. Treat visible damage and tunnels on the trunk with boric acid solution. Dust diatomaceous earth into cracks and crevices as a physical barrier. Repeat nematode and boric acid applications every few weeks.
This combined strategy pressures the colony from multiple directions. The nematodes attack termites in the soil, the boric acid poisons those feeding in the wood, and the diatomaceous earth picks off stragglers moving across treated surfaces.
Protecting Nearby Trees and Structures
Termites in a tree are often part of a larger subterranean colony that could be targeting other trees, fences, or your home’s foundation. Clear any dead wood, stumps, and debris from around the infested tree, since these provide additional food sources that sustain the colony. Keep mulch pulled back at least six inches from tree trunks and foundation walls. Fix any irrigation leaks or drainage problems that keep soil consistently wet near structures, as moisture is what subterranean termites need most.
When Natural Methods Aren’t Enough
If the tree has large hollow sections, visible structural weakness, or the trunk sounds extensively hollow when tapped, the damage may be too severe for natural treatments to matter. A tree with more than roughly a third of its internal wood consumed becomes a falling hazard, especially in storms. At that point, the priority shifts from saving the tree to preventing property damage or injury.
Similarly, if you see mud tubes extending from the tree toward your home’s foundation, or if the infestation persists after two to three months of consistent natural treatment, the colony is likely too large or too well-established for DIY approaches. Professional pest control services use baiting systems that workers carry back to the colony, gradually killing the queen and collapsing the population from within. That colony-level control is something natural spot treatments simply can’t replicate at scale.