Are stink bug traps effective?

The strongest data point in this space comes from a Virginia Tech field study led by researchers Aigner and Kuhar, run across sixteen houses over two years and reported by Virginia Tech News. Their homemade trap design — a simple roasting pan of soapy water placed beneath a light source — dramatically outperformed commercially sold stink bug traps deployed alongside it in the same trial. That's a real, credible result, and it's well worth building.

What gets lost when the number circulates online is the season the trial captured. Stink bugs respond to that trap because of a light-driven behavior that is strongest in spring, as daylight lengthens and overwintering adults reactivate. The result doesn't say anything, by itself, about how well any trap performs during the fall entry period or the depths of winter — and those are the seasons most people are actually searching this question in.

Commercial stink bug traps typically rely on an aggregation pheromone lure — the chemical signal stink bugs use to find each other. USDA-ARS entomologist Rob Morrison and colleagues, publishing in the Journal of Economic Entomology, found that stink bugs "began to respond reliably to pheromone-baited traps after a critical photoperiod of 13.5 hours" — a daylight length that only occurs in spring, not during the fall entry period or the short-daylight winter months when most homeowners are dealing with bugs indoors. During that fall-winter window, Morrison's field observations found traps capturing just "eight to 20 percent of the stink bugs we saw crawling around hallways." Trap-lure product documentation confirms the same limitation directly: the lures are explicit that overwintering adults will not respond to them indoors. A trap bought in November, in other words, is not broken — it's simply being asked to work during the one part of the year the underlying biology doesn't support it.

Put the two findings together and the candid advice writes itself. If stink bugs are in your house right now, in fall or winter, skip the trap entirely and vacuum — it's the method the EPA and university extension programs actually recommend, and it works regardless of the season. If you're willing to wait for spring, or you're planning ahead for next year's emergence, the DIY light-and-soapy-water pan trap has real field evidence behind it and costs little to assemble from things most households already have. Either way, the trap — of any kind — is a secondary tool. Sealing entry points on the home's warm southern and western exposures before stink bugs start staging there each September remains the intervention that reduces how many you have to deal with in the first place.