About a year ago, we remodeled our den and got new built-in book shelves and cabinets. We recently discovered the holes and powder of powderpost beetles. Our exterminator came and drilled each exit hole that we could find (50+) and sprayed in each hole. The wood is a thin veneer so I think the penetration is good. We are now monitoring for new holes and more powder. There is a void space behind the bookshelves and the room on the other side of the wall is my bedroom. After reading your articles, I’m wondering if it would be best to possibly take down the sheetrock in my bedroom and try to get at the bookshelves from behind to apply the Boracare. I really don’t want to have to rip out my brand new bookshelves because they are tied in to some stonework and I don’t want to have to tent the house because I know that will be very expensive due to the size of the home but I definitely want to stop the beetles from spreading. What do you think?
I definitely lean towards going for it and getting it treated. I say this for a few reasons. First, you don’t mention the wood type of where the holes were found but I’m thinking it’s some kind of softwood. And if it is, the type of beetles that can get in there can do damage quickly. They also tend to “stray” more than others and without being able to see the back side of the shelves and cabinets, I’d be uncomfortable leaving it as is without a more a thorough treatment.
Second, as our POWDERPOST BEETLE ARTICLE explains, treating exit holes isn’t really a viable method of controlling this pest unless the holes are covering the entire length of the wood. In other words, for as many exit holes you’re finding, there are probably a lot more hidden along stretches of wood you can’t reach. These hidden areas could turn out to be significant in the long run and if it was my home, I’d have trouble ignoring this possibility.
Third, based on the design details you described (stone work, inaccessible back side of the cabinets and nicely finished bookshelves), the approach of coming in from behind is definitely warranted. Additionally, it would afford you the opportunity to get both the shelving and the innards of the wall (studs, sill plate, etc.) at least inspected to make sure nothing is active. And while you’re at it, if you’re that far in there, you might as well treat with some BORACARE and be done with it.
So in summary, leaving this one alone would be a big gamble resulting in not only a large treatment expense down the line, but a lot of aggravation and mess. Alternatively you could tackle it ahead of time before anything significant can develop. By doing so you’d be preventing any massive job involving not only a treatment, but a lot of damage repair.
Here are direct links to the information and products mentioned above:
Powderpost Beetle Article: http://www.powderpostbeetles.com/powderpost-beetle-control