Fall-Season Invaders

With the arrival of cooler weather, pest pressure increases on the perimeter of structures as insects move indoors seeking shelter from the cold.

As a result, service calls for boxelder bugs, Asian lady beetles, brown marmorated stink bugs, millipedes, spotted lanternflies and overwintering insects increase as customers begin encounter fall invaders in growing numbers.

Fall is also the time of year when outdoor cockroach populations peak, creating a variety of control challenges for PMPs. There’s a biological reason for this phenomenon, according to Techletter, a publication of Pinto & Associates. “Most peridomestic cockroaches are large species with slower life cycles than smaller domestic cockroaches. Unlike German cockroaches that reproduce year-round, Oriental and American cockroaches, have just one generation a year.”

Since American cockroach nymphs hatch from egg cases in June in most regions of the country, by fall, these late-stage nymphs are seeking out food and overwintering sites, along with the adults. “At this time, they often enter substructures,” Techletter states.

WHAT TO DO? So what’s the best plan of attack for PMPs encountering these situations? “When I talk about perimeter pest management, I suggest PMPs think of their accounts like a boat on the ocean,” say Joe Barile, technical service lead, Bayer Environmental Science. “Around the perimeter of a home, occasional invaders and overwintering pests are coming in to take advantage of the resources structures provide – food, water and shelter.” 

And the perimeter of a structure is the first line of defense around a home or business, a location attractive to insects because it provides an attractive microenvironment to live and reproduce. “Our first obligation when thinking about perimeter pest management is to take these ‘safe spaces’ away from these insects,” Barile says. “To keep that ship on the ocean water-tight.”

While such an approach “sounds like a no brainer,” Barile says, it’s often easier said than done, requiring a commitment on the part of the technician to not only perform a thorough inspection, but take a “targeted approach” to structural pest control. 

“The key is to put product where it is going to intercept the pest most effectively,” Barile says. “No longer can we rely on area-wide spraying to control perimeter pests. Today, we need to be more targeted in our approach.”

In addition to applying Barricor as a coarse low-pressure spray to mulch and the sides of structures at a maximum height of 3 feet above grade, applications should be made to other common entry points around structures (i.e., heating and plumbing lines, foundation cracks, dryer vents, etc.).

“I recommend PMPs target two specific areas,” Barile says. “First, it’s important to target the sill plate, where the house sits on the foundation. It’s a very important place to put your insecticide. This is often the front door to the structure for insects. You want to drive product under that sill so it comes into contact with any insects trying to enter the structure.

“Second, target the foundation and any mulch beds around the perimeter of the structure,” he says, “Mulch is a complex surface that insects find very attractive, so it’s critical you treat these areas.”