Home Invaders

It's that time of year again: the growing season is almost over, temperatures are cooling off, and your home becomes a warm and inviting place...for insects.

One of these "home invaders" is the Western conifer seed bug (Leptoglossus occidentalis). This is a fairly large bug (about 3/4 inch long), with back legs that have a distinct flattened leaf-like shape, and alternating white and brown marks on its lower body, surrounding the wings (see photo). At this time of year, you may find one lurking around the foundation of your house, or buzzing around a window screen, looking at your home as a perfect shelter for the winter. If you have encountered this insect pest before, you probably remember it best by the acrid, citrusy-smelling liquid it emits when startled.

Western conifer seed bugs are native to the west coast of the USA, but have been established on the east coast since the 1990s. While they are only considered a minor pest of the coniferous trees they attack (pines, Douglas fir and hemlock), they can be a major inconvenience if they find a way to enter your home. Small infestations can be handled by sealing up any parts of your home that the bugs could be using to sneak in (holes in screens, chimneys, loose window fittings) and by capturing escapees by hand or by shop vac. Larger infestations may require consultation with a licensed pest specialist.

To learn more about the Western conifer seed bug, read this fact sheet from Cornell University's Insect Diagnostic Laboratory.