In the 1930s, California researchers began injecting arsenic into active infestations of drywood termites
, finding that the termites not killed by the initial application usually succumbed to toxic residues. Now 80 years later, a natural product, orange oil, is being marketed as a herbicide and insecticide, with particular kudos to its effectiveness against drywood termites. So, what is this wonder product and how does it kill termites?
What is Orange Oil?
Although orange oil smells strongly of oranges, it is not orange juice, but an extract from orange peels that is insoluble in water. Drinking a cocktail of it would cause severe stomach upset and spills are irritating to both eyes and skin. Some people even suffer severe allergic reactions upon exposure so, as always, caution is advised not only for the applicator of orange oil, but for those who will occupy the structure after treatment.
How Does Orange Oil Kill Termites?
The active ingredient of orange oil is D-Limonene,
a chemical known to be an effective insecticide against a variety of pests from flies
, to mosquitoes, ants, crickets and mites
. Scientists say that the oil dissolves the termite's exoskeleton, destroying the insect's cell membranes and triggering a lethal chain of events that ends with the bug dying from massive losses of water and protein.
Inspect, Inject and Inspect Again
The mode of treatment once a drywood colony has been found by canines
or humans is to drill holes into the infested wood and to inject the orange oil into the hollow spaces where the termites are feeding. Studies show varying amounts of residual effects from three days to three weeks. The majority of termites are killed by direct contact and since orange oil deters them from feeding, some will simply starve. After the treatment, the home or business owner should periodically check for signs of new infestation. Trained canines have been very effective in sniffing out new or previously undetected termite colonies.
The Future of Orange Oil
So, although the jury is still out on orange oil being a do-all, end-all termite treatment, it is certainly worthy of consideration as a least-toxic termite management option.