How to treat wood borers infesting a post?

John9

I spotted frass at the bottom of this post and cleared it away and saw fresh frass the next day. I can't see bore holes but the insects have probably entered underneath the post or by the supporting bracket.

Can someone suggest what is the best way to treat the post to remove them - thanks

MitchellMc

Hi @John9,

Unfortunately, I'm not aware of any products specifically designed to eliminate borers once they're inside a structural post.

At Bunnings, we stock a range of termite treatment products, such as https://www.bunnings.com.au/hovex-1l-ultra-lo-odour-termite-concentrate_p3010162 , https://www.bunnings.com.au/richgro-500ml-termite-and-ant-killer-concentrate_p0046395 and https://www.bunnings.com.au/david-grays-500ml-ant-and-termite-spray_p3015755 . These products are intended for termite control and may help if the insect is accessible, but in your case the borers appear to be inside the post or entering from underneath the mounting bracket, making them difficult to treat effectively with a surface-applied product.

If you do decide to use one of these products, be sure to carefully follow the manufacturer's instructions and wear the recommended personal protective equipment, such as gloves, eye protection and a mask where required.

Because the activity appears to be in a concealed location, I'd suggest contacting a professional pest controller for advice. They may be able to treat the post using a more targeted method, such as enclosing and fumigating it, which is more likely to reach the insects than a liquid spray.

If the infestation is extensive, the other option may be to replace the post entirely.

Please let me know if you have any questions.

Mitchell