It is easy to overlook these holes present in mostly aging structural boards. These are caused by a common wood-destroying organism called Anobiid beetle. They enjoy laying eggs in soft wood like Douglas Fir, then the larvae hatch and consume the wood fiber as they mature into adulthood. Usually they will depart after adulthood but sometimes they can return, consume more and lay eggs. Exit holes are usually the size of the end of a ballpoint pen and the more exit holes usually indicates a more extensive infestation. In many situations structural integrity of the boards is compromised. I have seen some cases where boards have been crushed under their load causing the house to settle (see the picture below).
When I see these, like I did at an inspection last fall, the culprit is usually long gone leaving the damaged materials behind. The treatment is fumigation by a pest control specialist if there is reason to believe the beetles are still present or might return. If structural damage has occurred the damaged wood is removed and replaced with sound materials.
Wood left with moisture levels about 20-percent is most susceptible. That is why keeping crawlspaces free of standing water is important. But usually the infestation is in the manufacturing process when wet boards sit in the lumber yard. I have found this to primarily be a problem in older houses – I’ve yet to see this with newer construction.
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It is easy to overlook these holes present in mostly aging structural boards. These are caused by a common wood-destroying organism called Anobiid beetle. They enjoy laying eggs in soft wood like Douglas Fir, then the larvae hatch and consume the wood fiber as they mature into adulthood. Usually they will depart after adulthood but sometimes they can return, consume more and lay eggs. Exit holes are usually the size of the end of a ballpoint pen and the more exit holes usually indicates a more extensive infestation. In many situations structural integrity of the boards is compromised. I have seen some cases where boards have been crushed under their load causing the house to settle (see the picture below).
When I see these, like I did at an inspection last fall, the culprit is usually long gone leaving the damaged materials behind. The treatment is fumigation by a pest control specialist if there is reason to believe the beetles are still present or might return. If structural damage has occurred the damaged wood is removed and replaced with sound materials.
Wood left with moisture levels about 20-percent is most susceptible. That is why keeping crawlspaces free of standing water is important. But usually the infestation is in the manufacturing process when wet boards sit in the lumber yard. I have found this to primarily be a problem in older houses – I’ve yet to see this with newer construction.
