What’s That Smell!?

Throughout the past year I have received a great number of calls from citizens with one of their greatest fears realized, stink bugs! These little critters pack a wallop greater than most creepy crawlies and sometimes leave a lingering effect. This bug not only fits all the descriptions of a true bug, including its piercing mouth parts and antennae, but also boasts a pungent odor (an unmistakable smell when crushed). While there are several types of stink bugs that inhabit Jefferson County there is a bug on the block, the brown marmorated stink bug (BMSB). The BMSB was first discovered in the US in 1996 in Allentown PA. Since its discovery it has continued to move not only throughout the US, but throughout Tennessee and has been identified in several counties. As several have seen, Jefferson County is one of those counties. But why such an uproar? Simply put, these bugs came from Asia and have been a nuisance that is growing. The BMSB sucks plant juices which causes problems in not only field crops, but has been seen feeding on a wide array of plant life including vegetables, fruits, and ornamentals. For most homeowners, however, this pest is simply annoying. Stink bugs often times work their way into homes, garages, and other structures seeking shelter. These bugs have the ability to overwinter much like the lady bug causing the increased cases of home infiltration during times of cooling temperatures.

Identification of stink bugs, even the BMSB, by a homeowner should not lead to panic. Some stink bugs are even beneficial such as the spined shoulder bug which is sometimes mistaken as the brown stink bug. The BMSB can be identified fairly easily as it is about 5/8 inch long and similar in width. They are mottled brownish grey and have black antennae marked with a white band on the next to last segment. There are dark bands on the membranous part of the wings and have coppery or bluish metallic depressions on the head and the area behind the head. There are also abdominal segments protruding from the wings that are marked with white and black bands. Other common stink bugs include both the green and brown stink bug. As described in a UT Extension Publication, “Both green and brown stink bugs are found throughout the state. Stink bugs have a wide host range that includes many cultivated crops such as corn and cotton, as well as numerous uncultivated plants. Overwintering adults become active in the spring. Stink bug eggs are characteristically laid in a mass of 20-100 barrel-shaped eggs. Eggs hatch in 6-7 days during the summer. Nymphs tend to remain clustered until the third or fourth instar. Most species pass through five immature (nymphal) life stages, requiring 23-25 days at optimal temperature. Adults live several weeks or longer. Several generations occur each year in Tennessee.”

Knowing the background of these pests is interesting, but often times homeowners are simply wanting to know the answer to one question, how do I get rid of them? The solution often involves several steps and some patience. By far the best way to control stink bugs in the home is through exclusion. Often time complaints come not because the bugs are present on a plant outside, but because they have made their way inside the home. In order to keep them out of the home we must take several steps to properly seal our homes. Homeowners should seal all cracks around entry points including doors, windows, pipes etc. This should be done with the appropriate sealant; silicone-latex caulk is often a good choice. If using window unit air conditioners, home owners should have the units removed by mid-September eliminating this common entry point. Chemical Sprays and traps are also available commercially. These sprays are in the pyrethroid family and are typically applied as a perimeter spray. This can help decrease the total number of bugs that enter the home, but the sprays often have a limited lifespan due to the effects of sunlight. Chemical insecticides do have other drawbacks. As always particular care must be taken in order to use the product safely and as directed, but even when properly used can create other problems as the dead bugs can attract carpet beetles which also attack other products within the home including fabrics, woolens, and dry goods. In general, the best approach to solving another pest issue includes a multi-faceted approach and persistence.