How to Kill Termites With Boric Acid

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Termites are one of the direst banes of any homeowner's existence. These tiny bugs live on the cellulose in wood. They're silent and stealthy and, if unidentified and left to their own devices, can cause enough structural damage that they literally eat you out of house and home. Professional extermination can be costly and involve toxic chemicals. If you identify the problem early enough, you may be able to nip it in the bud with boric acid.


How to Kill Termites With Boric Acid
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How to Identify Termites

Most termites stay well hidden, so you're unlikely to see them in their larval stage. But, they get bolder as they grow and are often attracted to light sources, just as moths are. Before panicking at the sight of a small, winged intruder, take a good look because termites greatly resemble the less harmful flying ant. Termites have straight bodies whereas flying ants have a clearly visible small waistline separating their upper and lower bodies. Both have four wings. On termites, all four are the same size, while the front wings of a flying ant are longer than their rear wings. Termites have straight antennae, and flying ants have bent ones.


How Boric Acid Works

Boric acid is a natural pesticide and wood preservative. It doesn't kill termites on contact. When they lick the boric acid off of themselves and swallow it, the boric acid inhibits the absorption of nutrients, starving them no matter how much of your house they eat.

How to Use Boric Acid

Boric acid is generally sold in powder form. This can be sprayed as is or diluted with water. Powder sprayers are available at most home improvement stores. Follow the manufacturer's instructions for use, and make sure that you wear goggles and a dust mask. Spray the powder in any areas you suspect termites may be nesting. This method is best for outdoor use. For indoor use, mix one teaspoon of boric acid with one cup of warm water in a clean spray bottle. Shake the bottle gently until the powder is dissolved. Soak all areas that you suspect are infested by termites. Repeat every day for three to five days, and then search for signs of further termite presence or damage.


When to Call a Professional

While termites will sometimes leave droppings and discarded wings or flit brazenly around your lights, they can also be more subtle. Paint that peels or bubbles can be a sign that you've got a termite problem. This is caused by the moisture termites bring to their nests to help them thrive. Another sign of a serious termite infestation is wooden floors that buckle upwards or feel spongy when you walk on them. This can mean that a termite colony is thriving between the wooden floor and the subfloor, and a colony that large requires professional extermination.



Brynne Chandler built her first bookcase at eight years old, which is also right around the time she started writing. An avid crafter, decorator and do-it-yourselfer, Brynne has remodeled several homes including one cantilevered on a cliff and one that belonged to Olympic swimmer and actor Buster Crabbe. Best known for her EMMY-nominated TV animation writing, she has been writing non-fiction content for almost a decade and has been featured in the San Francisco Chronicle and the Houston Chronicle online, among other places.

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