When deciding on a termite control treatment method, it is always important to consider all the options. Today, more than ever, people are increasingly concerned with the use of chemicals for both personal health and environmental reasons.  This has led some homeowners to explore the “famous” orange oil termite treatment method. So, what exactly is it, how is it carried out, and does it even work?

Orange oil contains an active ingredient known as d-limonene. D-limonene is the same compound found in many common household products (such as orange oil furniture polish, orange scented fragrance products, and orange based cleaners), and is extracted from orange peels.

Orange oil also contain plant oil compounds called terpenes, and is responsible for giving oranges their familiar smell. Because d-limonene is considered to be quite safe, with a low toxicity level, it has been gaining attention in current termite control methodology. Termites get killed by orange oil because it damages their outer exoskeleton, causing desiccation leading to death.

Orange oil termite treatments are designed to work in localized areas only, where the termite infestations are verified to be occurring. The oil only kills termites in the areas that have been treated. All experiments have constantly shown orange oil to be effective in killing all kinds of termites as long as they are exposed to it long enough.

Termite treatments involving orange oil require drilling into the infested wood, and then injecting the oil directly into the chambers to reach the termites. While orange oil can be an effective termite control method, it should not be assumed that you will never need other types of chemical-based or fumigation treatments.

NB: Tent fumigation techniques are the only type of control method that actually come with a guarantee stating all termites are killed throughout the whole structure in one treatment. The reason for this is because the majority of a structure’s framing is covered with various materials such as insulation, plaster, drywall, floor coverings, paint, and roofing materials. Poisonous gases like carbon dioxide or methyl bromide, and are pumped into the covered house and left for a period.

This does not mean that every house needs to be fumigated.  The types of termites present, the number of termites present, and the number of areas infested, all factor into determining the proper treatment; which is precisely why you ultimately need to consult your professional exterminator.

Orange oil effectiveness

Treating in a localized method, such as with orange oil, will only control termites in precise areas where the insects have actually been seen. Since termites can move their foraging to new areas fairly easily, new infestations can crop up quickly.  If you are not able to reach these areas, the new infestations can go completely unnoticed.

And all this is why orange oil treatment is mostly only applicable for drywood termites, and hardly effective for subterranean termites. Drywood termites have far smaller colonies compared to subterranean termites and are far less mobile; thus a correct application of orange oil on their nests can eliminate the entire colony. Even then, the oil needs to be applied to chambers that are actively occupied by termites; otherwise it won’t be effective.

Termites are killed through 1) direct contact 2) breathing in the fumes 3) eating the poisoned wood. Common sense dictates that orange oil treatments will not kill all the termites in any given medium to large sized drywood termite colony, although some will undoubtedly be killed through its fumigation effect. This fumigation effect is reduced if the wood is moist; most of the fumes will be absorbed by the wood. This is why accurate application is necessary.

Measure of effectiveness

Accurate data on the effectiveness of orange oil treatment based on the number of callbacks is quite sketchy. A “callback” means the pest control operator needs to return to perform another treatment, due to renewed infestation activity. Some callback figures have been quoted as somewhere between 5-20%.

Pros and cons of orange oil as a termite control method

In order to fully understand if an orange oil treatment is right for you, carefully consider all of the advantages and disadvantages.  Here are a few key pros and cons for easy reference:

Advantages:

• There is no need to vacate the premises during the application.
• There is no residual effect.
• There is no need to remove pets or houseplants from the property during treatment.
• D-limonene (the active ingredient) is much less toxic compared to most other termite chemicals.

Disadvantages:

• Orange oil will only control termite infestations that can be seen, not infestations in other areas. Its effects are localized.
• There are no residual properties of orange oil (for future control). You need to keep applying it if new infestations occur.
• Orange oil treatments require drilling into wood and wall components of the home.
• Orange oil is mainly only effective against drywood termites, not subterranean termites.
• Treating large areas with orange oil may be more expensive than other treatment methods.
• Orange oil (with its high turpene content) may cause paint to peel off as its effect on paint is similar to nail polish.
• Orange oil is flammable, so there is a (very) small fire risk.