In April 2021, many internet users encountered a seemingly clever trick to deter wasps and yellow jackets from entering their mailboxes: Simply place a few dryer sheets inside.
This piece of advice came from a post on the "You Should Know" section of Reddit from someone who identified themselves as a letter carrier. The post informed readers that if they found a dryer sheet in their mailbox it was likely from their mail carrier who was attempting to thwart "those dastardly devils" that had built a nest in the mailbox.
Letter Carrier here.
We're almost to the month of May which means nice weather, hanging out outside, school closing for the summer, and the return of those dastardly devils: Yellowjackets and Wasps.
I'm sure you've noticed. But just in case you haven't, this time of the year wasps and Yellowjackets (especially Yellowjackets) like to make nests inside of mailboxes. In a lot of places this time of the year, it's just beginning to warm up outside, but it's still fairly cold at night. So mailboxes provide nice, easy shelter for them.
I can't tell you how many times, especially during this part of the year, where I've opened up a box to see a little nest with 3-5 Yellowjackets just chillin. If I'm really unlucky, they will have made their nest at the very back of the box so I wind up sticking my hand in not knowing they are there. We all know how temperamental these little douchebags are and merely existing in their presence is enough to piss them off. Last year alone I was stung 10 times on 10 separate occasions.
Getting to my point. We've found that they hate scented dryer sheets. If we encounter a box that is a problem for nests, we'll often put one in there and it does the trick.
So please, if you one day randomly see a dryer sheet at the back of your mailbox, just know that your carrier more than likely put it there to deter these Satanic creatures from building their home in it.
While this method may be utilized by some mail carriers, the Postal Service does not instruct its employees to put dryer sheets in mail boxes to repel wasps. Kimberly Frum, the senior public relations representative for USPS, told us that the organization's safety guidance does include some tips about how to handle problematic insects (including reporting nests to supervisors, using repellents when appropriate, and avoiding the consumption of sugary beverages outdoors), but these guidelines do not mention dryer sheets.
There is guidance in our safety regulations that cover how to handle insects. The guidance includes, but is not limited to:
- reporting hazards to a supervisor (i.e., hornet, wasp, and bee nests) so they can be removed by the property owner
- using insect repellant as needed/when appropriate
- avoid wearing perfume or other scented products
- watch eating and drinking outdoors, especially with sweetened drinks as this attracts bees and other insects
It is advised when a carrier approaches a mailbox, they should look for wasp nests and the nests of other insects, or insects flying around flowering plants. Being aware of your surroundings is paramount in avoiding contact with unwanted pests.
But no dryer sheets.
This Reddit post was not the first to offer this advice. The claim that dryer sheets repel wasps has been repeated over the years in news articles and on a variety of gardening, pest management, and even cooking websites. The one place we have not found this claim, however, is in academic journals.
There appears to be some anecdotal evidence that dryer sheets repel wasps, but it doesn't appear this claim has ever undergone the scrutiny of a scientific test. In 2010, entomologists at Kansas State University found that dryer sheets repelled fungus gnats, but this study did not examine the effect of dryer sheets on bees, wasps, hornets, or yellow jackets.
On the other hand, we weren't able to find any studies that disproved this idea, either. Some blogs claim that dryer sheets don't repel wasps, but the only supporting evidence offered is a reported comment from the director of research and development for RESCUE!, a brand of insect repellent.
The Garden Media Group blog writes: "Director of R&D for RESCUE!, Dr. Qing-He Zhang says that it is highly unlikely that yellowjackets would be repelled by the perfume-y smell of the dryer sheets; they may actually be attracted to it because of the flower-like odor."
Since this comment comes from a person who may have conflicting motivations (RESCUE! is in the business of selling insect repellents, not dryer sheets), this should also be taken with a grain of salt.
If dryer sheets truly did repel wasps, it stands to reason that they would contain an ingredient known to repel insects. However, there doesn't appear to be much overlap between the ingredients found in a typical dryer sheet and a list of ingredients found in insect repellents from the Environmental Protection Agency (EPA). The one exception could be a fragrance, such as citronella-scented dryer sheet, which could act as a mild deterrent, although we'd doubt it would be enough to repel a wasp.
We reached out to various entomologists (and the United States Postal Service) and we will update this article if more information becomes available.
In addition to its alleged ability to repel wasps, the humble dryer sheet has also been touted as a cure-all of sorts for everything from getting rid of musty book smells, to removing static electricity, to dissolving soap scum. Read our article covering 16 unusual uses for dryer sheets here.