I hate stink bugs.  Out of nowhere, they appear in weird places in my house, like on my toothbrush.  Where did they come from?  How can I safely get rid of them? 

Here’s the good news.  As far as Germantown residents are concerned, stink bug season is almost over. 

“By June, most people shouldn’t be seeing them in their homes any more,” said Tracy Leskey, a research entomologist with the Appalachian Fruit Research Station.  Right now, stink bugs are trying to get out of our houses to go mate, lay eggs and start their life cycle all over again.

And that’s the bad news.  The stink bugs that we are seeing now have probably spent the winter inside our homes, most likely in the attic.  This fall, their offspring will be back.  According to Leskey, the peak period of stink bug movement into overwintering sites is in the third week of September.

Why are there so many stink bugs these days? 

Officially known as the brown marmorated stink bug, these insects are recent immigrants to the United States.  Stink bugs are thought to have been introduced accidentally in the late 1990s in Allentown, Pennsylvania.  Known to be great hitchhikers, they probably arrived in cargo. In 2003, Leskey confirmed the first stink bug sighting in the state of Maryland, in Hagerstown. 

Prior to 2008, Maryland farmers didn’t notice major problems from stink bugs.  But late that year, stink bugs created havoc by feeding extensively on ripened fruit in commercial orchards. Leskey and her colleagues started actively studying the insect in 2009.

Today, stink bugs have been detected in every state east of the Mississippi.  No one knows the extent of their range or how far they might travel.  Native to mainland China, they have no natural predators in the United States … except for my neighbor’s dog.  I asked Leskey if eating stink bugs is harmful for pets.

She laughed, then replied, “Everything in moderation.”  She said that stink bugs have defensive compounds, which aren’t toxic, but ingesting lots of bug exoskeletons wouldn’t be great for a dog’s stomach.  “If you have hundreds of them in your home, I wouldn’t let the dog just gorge on them.  There’s no evidence that they are harmful or make animals sick, but be cautious.”

What’s the most environmentally friendly way to get rid of stink bugs? 

My way of disposing of stink bugs is to catch them with a tissue and flush them down the toilet, which surely is a waste of water.  I asked the experts for their suggestions.    

Leskey said that the best way to get rid of stink bugs in your house is to suck them up in a dedicated vacuum and then get rid of the vacuum bag.  Some people drop them into jars of soapy water or spray them with soapy water to kill them first. 

Mary Kay Malinoski, an extension specialist with the Home and Garden Information Center at the University of Maryland Extension, seconded Leskey's ideas.

“There’s no really good insecticide for homeowners to use on bugs indoors,” Malinoski said.  Her organization discourages the use of broad spectrum insecticides because some bugs are beneficial.  “We don’t recommend spraying anything in the house.  Stay away from insecticides in the house because you’re being exposed to them as well as your pets.  It helps to reduce risk.” 

Both Leskey and Malinoski said that stink bugs tend to favor the attic.  If you see stink bugs in your home, that’s most likely where they are coming from.  These insects like to tuck into the layers between the insulation and the roof.

“Figure out where they are getting in – a window that’s not tight, a door threshold that’s got a gap under it,” said Malinoski.  Tighten up your home with weather stripping and caulk.  Seal cracks in the foundation, tack down loose siding, and screen the chimney tightly. 

According to Malinoski, prevention is the best way to keep stink bugs – and other insects – from living in your home.  This summer, when stink bugs are finally out of the house, would be a great time to prepare for the fall stink bug invasion.