Wood Destroying Powderpost Beetles- What Can We Do?
Wood destroying powderpost beetles can be a real pain to figure out. Recently, I inspected a cabin in Cleveland, Georgia. Our client was concerned she had termites because she was seeing piles of frass outside of her cabin in the woods (think small wood shavings and fecal droppings).
This was not a case of a subterranean termite infestation. Simply put, subterranean termites will cause wood damage originating from the ground up. Subterranean termites will create mud tubes that they use to travel back and forth from the ground. If they were to emerge from a piece of wood, they will usually plug them up with mud. If they expose themselves to the open they will dry out and die.
Powderpost beetles on the other hand are good at hiding and only leave their signs of infestation behind. Typically, you will only see signs that they were there. Signs to look for are small, round exit holes with piles of frass at the bottom (see photo below). Sometimes you run into their activity in the cooler months and you need to find out if they are active or not. Activity is determined by:
- The color of the frass (dingy, yellow frass equals old activity and light colored frass means newer activity)
- Mark off an area with scotch tape to cover existing holes and parts of wood with no holes. Come back when it is warmer and look for holes in the tape where you covered the wood. If you see holes, then the activity is new.
- Use a black magic marker and tap it on existing holes in a defined area. Then come back and see if new holes are present.
There are four main types of wood destroying powderpost beetles- Lyctid (true powderpost beetles), Bostrichtid (false powderpost beetles), Anobiid (deathwatch beetles), and Cerambycids (old house borers). I have included a link here that details their life history and their control in detail.
So, what did I tell our client? I told her that she basically had three options. First, she can fumigate (really expensive and no residual protection). Second, she can apply a boric acid insecticide to stripped wood so it can penetrate the wood and help control developing larvae. Finally, she can paint the cabin with either a thick coat of varnish or paint. Activity was mainly on the exterior of the cabin, so painting it should help prevent further activity. I made sure to tell her to allow for any existing larvae to emerge after it is painted/protected. Their development time can take years depending on the environment. However, this was likely the most economical and simplest approach to controlling the powderpost beetle activity.
If you find yourself needing pest control and/or help with wood destroying powderpost beetles, contact Grace Valley Pest Control today! We service the Cumming, Dahlonega, Dawsonville, and Cleveland areas of Georgia. We offer commercial and residential services to fit your needs!