Patrick T. Copps

Summer is gone, and fall has arrived. That means cooler temperatures, pretty leaves and a new lineup of holidays. It also means a new list of pest threats, some of which only pose an issue this time of year. And while general pest activity appears to slow down at this time of year, these fall invaders – including ladybugs, cluster flies and stink bugs – are rooting for you to lose focus on your pest management program.

Fall invaders may try to sneak into your healthcare facility looking for a home where they can survive the winter. They often go into hiding where no one can see them, which means they frequently go unnoticed and are forgotten until they emerge, looking to get back outside when spring rolls around. By the time occasional invaders are recognized as a problem, the pest population may be fairly large and it can be too late for simple control measures.

Seasonal invaders include:

Stink bugs and box elder bugs

Stink bugs, box elder bugs and other fall pests have the ability to detect various environmental conditions like warmer surfaces. This is why they can often be found on the south- and west-facing walls of a building where the sun hits – they are looking for warmth.

These insects may not pose a serious health risk, but stink bugs and box elder bugs can make a big mess around your facility. Stink bugs are named for the smelly odor they produce when they’re threatened, and box elder bugs’ droppings, which are reddish-orange in color, are unsightly and can leave stains on walls, window ledges and blinds.

Cluster flies 

Cluster flies are slightly larger and darker than the common housefly and move more sluggishly. Much like box elder bugs and stink bugs, these flies also appear in heaviest concentrations on the sunny side of buildings in the late fall and early winter, when they are seeking warmth.

These pests often congregate at windows, which may not prevent entry into facilities. Cluster flies are capable of crawling through small openings in screens, doors, around vents and walls to find a secluded place to hide for the winter.

On sunny winter days, the wall voids and enclosed ceiling areas where cluster flies often hide inside a facility can become warm, causing them to think it is spring. If this happens, they may come out of hiding prematurely and move toward the light coming in through windows or from fixtures. They will cluster around the inside of the windows trying to get back outside and can leave stains on walls if crushed.

Asian lady beetles

Asian lady beetles – commonly known as ladybugs – were initially beneficial pests, brought to the United States in 1988 to help reduce native aphid populations that can ruin crops and other types of vegetation.

Today, Asian lady beetles have become a pest issue throughout most of the United States and parts of Canada. They occur in a wide spectrum of colors ranging from yellow to orange to red and have a varying number of spots.

In the fall, Asian lady beetles gather in large numbers on the outside of light-colored buildings. When they gather on walls, some find cracks or holes they can use to get inside. They hibernate through the winter and become active again in spring.

Stay on high alert

Fall pests share some similarities when it comes to pest management procedures. In fact, the most effective way to keep these seasonal invaders out of your facility is to focus on exclusion. It’s important to plan ahead and implement exclusion efforts like the following before temperatures drop and drive these pests indoors:

  • Inspect the outside of your facility frequently and carefully for potential ingress points.
  • Check the weather stripping on all exterior doors and repair any damaged window screens.
  • Seal any cracks around windows and doors with an appropriate caulking compound.

Just in case any of these pests make it inside, now is also a good time to work on your sanitation practices, which can help reduce breeding conditions and keep flies and other pests away. Request that employees clean food and liquid spills immediately, which will give pests less sustenance to make it through the winter.

These tactics should be part of your broader Integrated Pest Management (IPM) program. Work with your pest management provider on setting up a proactive IPM plan for your facility, which can help protect it from pests in any season.

Patrick Copps is Technical Services Manager for Orkin’s Pacific Division. A Board Certified Entomologist in urban and industrial entomology, Mr. Copps has more than 35 years’ experience in the industry. For more information, email Mr. Copps at [email protected] or visit www.orkincommercial.com