The brown marmorated stink bug (BMSB) is a common household pest that seeks shelter indoors as cooler weather approaches. This invasive species, first identified in the United States in the mid-1990s, often congregates inside structures during the fall and winter months. Rather than resorting to expensive commercial products or chemicals, a highly effective, low-cost trap can be easily constructed using simple household items. This light and water trap has been scientifically shown to outperform store-bought alternatives by a significant margin.
Gathering Materials for the Light Trap
The most effective trap design relies on light attraction and a simple drowning mechanism. Select a large, flat container with reflective sides, such as an aluminum roasting pan or a sturdy plastic tub, to hold the solution. Two quarts of water are typically needed to provide enough depth for the bugs to become fully submerged.
A few tablespoons of liquid dish detergent must be mixed into the water. The soap acts as a surfactant, reducing the water’s surface tension and making the trap lethal. This reduced tension causes the bugs to break through the surface and become mired beneath. Finally, a directional light source, such as a desk lamp, is required to attract the insects.
Assembling the Stink Bug Trap
The initial step involves creating the lethal solution by mixing the water and liquid dish soap thoroughly. For a two-quart volume of water, adding approximately two tablespoons of detergent is an effective ratio. Stir the solution until the soap is fully dispersed, but avoid creating excessive suds, which can hinder the bugs from falling in.
Next, position the container in the desired location, ensuring it is level and stable. Place the light source near the container so that the light shines directly onto the surface of the soapy water. The light acts as a lure, drawing the stink bugs toward the bright area and causing them to fall into the container.
This setup capitalizes on the insect’s natural attraction to light. As the bugs approach, they fall into the water, and the soap ensures their demise by coating their bodies and plugging the pores they use for respiration. This method has been shown by entomologists to be 14 times more effective than other traps.
Placement, Maintenance, and Safe Disposal
For maximum capture results, the assembled trap should be situated in a completely dark room where the light source is the only illumination. Stink bugs often congregate near windows and entry points, making these areas ideal for trap placement. The trap should be run overnight when the bugs are highly attracted to the light.
The trap requires daily maintenance, which involves checking the container and refreshing the solution. The soapy water should be replaced every few days or immediately if it becomes too diluted or overly full of trapped insects. Avoid flushing the insects, as this wastes water and is not consistently effective.
The safest method for disposal is to strain the dead insects from the water and seal them inside a plastic bag before placing them in an outdoor trash receptacle. Alternatively, the entire contents of the pan can be poured out and sealed in a bag. This careful removal helps ensure the bugs do not release their foul-smelling defensive compounds, which can linger if the insects are crushed.