The western conifer seed bug with its long legs and an antenna has tried to invade many of our homes this fall. I found a dozen or so of these slow-crawling bugs last week trying to access our house. I even had one land on my cap and try for a free ride into the house. But I know they are not trying to be a nuisance — they are just looking for a place to spend the winter where it is nice and warm.
The western conifer seed bug (Leptoglossus occidentalis) was first discovered in the western United States. Today its range extends across the northern United States into Canada.
Adults are 3/4 inch long and brownish on top. The upper (dorsal) side of the abdomen is yellow or light orange with five transverse black patches. This orange and black pattern on the abdominal dorsum is revealed during flight. The flight pattern and loud buzz produced by this strong flying conifer pest resemble those of a bumble bee. They can emit an unpleasant odor as a defense mechanism when panicked or squished. It’s in a family of insects closely related to the stink bug, but it isn’t really a stink bug.
Even though they are considered harmless they startle a lot of people because they show up out of nowhere. Western conifer seed bugs are intimidating and daunting looking. They’re slow moving and almost look prehistoric. If they’re not clinging to the windows or siding outside a home, they’re inside hanging around windows and doors and on curtains, pillows, and clothing.
Experts say fall is the time of year when the bugs begin making their way indoors through any crack they can find. Once they settle in for a long winter they’ll hardly be seen until a warm spell when they emerge from the walls, attic or other hiding spots.
They usually return to the outdoors by April to find coniferous trees to feed on immature seeds and cones. They prefer Douglas fir seeds and seeds of various other species of pine. Their consumption of these seeds can cause a loss of seed crop and can have an impact in the quality and viability of conifer seed crops.
Where the western conifer seed bug is a persistent nuisance in homes, the best method of control seems to be a mechanical exclusion. Some strategies to prevent this insect’s invasion are: replace loosely fitting screens, windows, and doors; caulk gaps around door frames, window frames, soffits and screen fireplace chimneys and attic and wall vents.
I find also that a vacuum cleaner is a pretty effective method of removing the sluggish slow moving bug from the house. Another option is just pick them up by the antennas and escort them out. Show them the door!
Enjoy Boundary County even if it does get a little buggy!