Salty Dog Pest Control

Tiny Round Holes in Your Crawl Space Beams?

Small round holes in crawl-space beams or subfloor, with fine flour-like powder beneath them, are the signature of powderpost or wood-boring beetles. Fresh powder means an active infestation quietly working through your structural wood.

Powderpost beetle holes and frass in a Whidbey crawl space

What’s most likely going on

Powderpost and anobiid beetle larvae tunnel through wood for months or years, then emerge as adults through those 1/16-inch exit holes, sifting out the talc-fine frass. Our damp, unconditioned crawl spaces are ideal for them.

What it means for your home

Repeated generations progressively weaken flooring, joists, and framing, and because the larvae work unseen, damage is often advanced before the holes appear. Higher wood moisture is what sustains them.

What to do next

We assess how active and widespread it is, treat the affected wood, and address the crawl-space moisture that lets the beetles thrive. You can read more in our Pest Library entry on powderpost beetles, or head straight to our Powderpost Beetle Treatment service.

Reviewed by Matthew — Salty Dog Pest Control. WSDA-licensed structural pest applicator (License #101709). Veteran- and family-owned, serving Whidbey Island, Fidalgo Island, and west Skagit County.

Frequently asked questions

How do I know if the beetles are still active?

Fresh, powder-fine frass and clean new holes indicate active emergence. Old, empty holes without new powder may be inactive — we can tell the difference.

Why are they in my crawl space?

These beetles favor higher-moisture wood, so damp, poorly ventilated crawl spaces are the most common place we find them here.

Not sure what you’re dealing with? Call (360) 206-3293 for a free estimate over the phone, or browse the full Pest Library.

Posted on Google Google
Chris Irish profile picture
Chris Irish
Google star 1Google star 2Google star 3Google star 4Google star 5Trustindex verifies that the original source of the review is Google.
Matthew is a rockstar! He came out on a Friday night after a full day to make sure we were taken care of! Highly recommend!
Posted on Google Google
Kristi Lovelady profile picture
Kristi Lovelady
Google star 1Google star 2Google star 3Google star 4Google star 5Trustindex verifies that the original source of the review is Google.
Prompt, efficient and on-time service. Invoices provide written and visual information of service rendered. Mathew is very professional and knowledgeable. Would recommend Salty Dog services.
Posted on Google Google
Michele C. profile picture
Michele C.
Google star 1Google star 2Google star 3Google star 4Google star 5Trustindex verifies that the original source of the review is Google.
We really like Salty Dog! Matthew is very responsive and always on time. His reports are thorough, he is on time and works with our needs! Thank you Matthew!
Posted on Google Google
Brenda Praggastis profile picture
Brenda Praggastis
Google star 1Google star 2Google star 3Google star 4Google star 5Trustindex verifies that the original source of the review is Google.
Matthew is conscientious and careful. He has worked closely with us to address all of our concerns. He has tailored his efforts to the unique demands of our house as he performed an exclusion. The rodent activity has disappeared inside the house and has been vastly reduced outside. We are very happy with his work.
Posted on Google Google
Sharon Heiber profile picture
Sharon Heiber
Google star 1Google star 2Google star 3Google star 4Google star 5Trustindex verifies that the original source of the review is Google.
Matthew solved our mouse problem! He quickly identified their entrance point and blocked it. That was last year. We haven't had a problem since. Thank you, Matthew!
Posted on Google Google
Sandi Peterson profile picture
Sandi Peterson
Google star 1Google star 2Google star 3Google star 4Google star 5Trustindex verifies that the original source of the review is Google.
We had not done pest control for quite some time, (our bad) and one day I needed service right away. Matthew came ASAP and got us started on the right track. He did work above and beyond what I expected for a more than fair price and shows up for scheduled maintenance as promised. He does a great job and I recommend him highly.
Posted on Google Google
Rodger Schnee profile picture
Rodger Schnee
Google star 1Google star 2Google star 3Google star 4Google star 5Trustindex verifies that the original source of the review is Google.
Matt at Salty Dog is both personal and professional, and provides services that are high quality, and very reasonably priced. He is clearly a service provider first and last. I've had previous experiences(with pest services and other) with national companies, when I felt I was sent a representative that was sales first, service provider 2nd. Matt is also well networked with contractors in our community, and gave me a couple great referrals for other work I needed done. The bottom line is that I highly recommend Salty Dog and Matt for any rodent/pest related issues.
Posted on Google Google
Nicholas Orozco profile picture
Nicholas Orozco
Google star 1Google star 2Google star 3Google star 4Google star 5Trustindex verifies that the original source of the review is Google.
Extremely helpful and quick service who took his time and treated the issues that I had on the spot. I absolutely felt like the work was quality and he did not rush until I was satisfied with what was done. Thank you very much for the help!
Posted on Google Google
britt buchan profile picture
britt buchan
Google star 1Google star 2Google star 3Google star 4Google star 5Trustindex verifies that the original source of the review is Google.
We’ve had an excellent experience with Salty Dog Pest Control. Matt’s attention to detail is outstanding, and what really sets him apart is his passion for treating the root of the problem—not just applying a quick fix. He took the time to explain what was going on, what he was doing, and why, which gave us a lot of confidence in the process. His communication is clear, timely, and thoughtful from start to finish. It’s obvious he truly cares about his work and his clients. Highly recommend Salty Dog Pest Control if you’re looking for someone knowledgeable, thorough, and genuinely invested in doing the job right.

Contact Form Demo