Around this time of year when the weather starts getting crisp and cool, insects start to seek asylum in warmer spots, most notably your home. Fall house invaders think that they want a warmer habitat but truly, it messes with their circadian rhythms, preparation for winter and survival. Insects that should be going dormant for the cold part of the year are kept active in heated houses. This continuing activity uses up stored energy normally reserved for survival in dormancy through winter months. Eventually most of these insects will die, they will not breed or even feed while indoors, but their presence, en masse, is certainly a nuisance.
Now would be a good time to begin inspecting your door jams, windows, caulking, screens and vents for possible routes of entry in need of repair. Pictured below are some of the most common fall house invaders in the northeast, this is by no means an exhaustive list, just a guide to identify some of the most common pests seen when fall arrives.
Brown marmorated stinkbug, Halyomorpha halys, are typically shield shaped and about 17 mm long at maturity. They feed on a variety of fruit and ornamental plants, including apples, figs, persimmons, mulberries and citrus. It is native to Asia and was first identified in the U.S. in 1998.
Boxelder bugs, Boisea trivittata, most often becomes a nuisance near plantings of boxelder trees. Adults are brownish black and approximately 12 mm long, appearing somewhat flattened on the top with reddish-orange coloration along the thorax and margins of wings, as well as abdominally. Boxelder bugs are native to the U.S. found throughout the east and as far west as Nevada.
The western conifer seedbug, Leptoglossus occidentalis, is native to the western U.S. but has been expanding its range and is now found across the northern U.S. and into Canada. Adults get to be approximately 19 mm and appear flat dorsally. They will be yellow to light brown with five transverse black patches. Conifer seedbugs feed on the seeds and developing cones of many conifer species, as their name suggests.
Ladybugs or lady beetles, Coccinella septempunctata, are members of the beetle family. Many species exist in the U.S., some native and some deliberately introduced. Adults can be 1 mm to 10 mm long, depending on the species. Ladybugs are generally considered to be beneficial insects and are sometimes used as biological control agents for pests. However, they have a fascinating defense mechanism, they are able to reflex bleed from their leg joints; their blood is repellant due to its odor and composition of toxic alkaloids.