COLUMBIA CITY, Ind. — Some insects and spiders will be trying to move in to homes as weather turns colder this fall. Here’s a brief overview of some of the more common insects and other arthropods that will be seeking shelter in our homes as colder weather becomes the norm.
Asian lady beetles are sometimes called Halloween beetles because of their orange coloring and propensity to show up around Halloween time. Although it’s not really an accurate name, “ladybug” is the common name most people use for a lady beetle. Their coloring can vary from orange to red, and they may have zero to several spots on their wing covers. A distinctive black ‘M’ can be seen behind their head, distinguishing Asian lady beetles from other native species of this normally beneficial insect. Lady beetles spend the winter in sheltered sites, but unlike other lady beetles, the Asian lady beetle is more likely to seek this protection in homes. Because of the sometimes-high populations of the insect, it can become a real nuisance.
True bugs include boxelder bugs and stink bugs. True bugs are in the insect order Hemiptera, meaning “half-wing” (the top half is leathery, while tips are transparent or membranous, and the wings are folded over the top of their back). So, all bugs are insects, but not all insects are bugs!
Boxelder bugs cluster on sides of boxelder trees, occasionally moving to cluster on sides of houses, eventually finding their way indoors. Their sheer numbers can alarm anyone. Adult boxelder bugs are black with reddish-orange line markings on their bodies. Nymphs, or immature boxelder bugs, are primarily red.
The brown marmorated stink bug is another true bug new to Indiana in recent years. Like all stink bugs, this insect has a shield-shaped body (somewhat like the shape of an interstate highway sign), but it has light bands on the last two segments of each antennae. The insect is a pest on fruits in the Eastern part of the United States, but it is becoming more common in Indiana and other Midwestern states. In the fall, this insect tries to move into our homes, much like the Asian lady beetle. The stink bug gets its name because it releases a pungent chemical as a defensive mechanism when threatened.
Dr. Tim Gibb, Purdue Extension entomologist, recently wrote, “A brown marmorated stink bug has a unique ability to store these chemicals as a very concentrated, extremely smelly liquid, which it can emit (as needed) through holes in the sides of its abdomen.” He said that it is a defensive mechanism – meant to protect it from being eaten by birds, lizards, or other animals.
“The magic potion not only reeks to high heaven, it also tastes bad and has even been found to be toxic in some cases,” said Gibb. “However, the bug does it, I can say that it works like a charm, because nothing I know has ever made a habit of eating them.”
I used the term “arthropod” in the opening, which refers to invertebrates with jointed appendages. Insects and spiders are both arthropods, but, as you probably know, insects only have 6 legs.
8-legged spiders are known as arachnids, related to ticks, mites and pseudoscorpions. Most spiders are beneficial creatures, acting as predators of insects. A couple of common spiders that invade homes are wolf spiders and jumping spiders. Though they alarm many people, these spiders are not considered a serious health threat to humans. Spiders of concern to human health include the black widow and the brown recluse. Both live in secluded spots, and won’t typically bite unless disturbed. However, get to know what they look like and be cautious! See the Purdue Extension publication entitled, “Spiders,” at https://extension.entm.purdue.edu/publications/E-72.pdf.
There are a few simple things homeowners can do to reduce the migration of home invaders each fall. The first is also a very energy-smart idea – seal all cracks around windows, doors, and utility entrances. Sanitation, indoors and immediately outside the home, will also help. There are some chemical options that usually involve an application of an insecticide product around the perimeter of your home. If opting for a chemical option, make sure that the product is labeled for the site of application and for the pest or pests you are trying to control. Always read and follow label directions, as these will vary from product to product.
Finally, Purdue Extension has information on these and other pests available free online at www.edustore.purdue.edu. Of course, a call to the county Purdue Extension office is also welcome.
— John E. Woodmansee, Purdue Extension Educator, Agriculture/Natural Resources
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