Brown marmorated stink bugs fly to overwintering sites in the fall, and Maryland Department of Agriculture material gives mid-September through October for that flight. They do not bite, and the university's advice is to seal cracks, weather-strip doors and windows, and remove window air conditioners before they arrive.
Key takeaways
- Brown marmorated stink bugs do not bite, according to University of Maryland Extension.
- MDA material gives mid-September through October for the flight to overwintering sites, while another MDA document gives October to November.
- Sealing is the main step: caulk cracks, weather-strip doors and windows and remove window air conditioners.
- Vacuum or release stink bugs outside rather than relying on indoor treatment.
- Spotted lanternfly is a plant pest under a Maryland-wide quarantine, not a household pest.
- Sightings of spotted lanternfly are reported to the Maryland Department of Agriculture.
When do stink bugs come into homes?
Maryland Department of Agriculture material gives mid-September through October for the flight to overwintering sites. Another MDA document gives October to November, so the window can vary by year and by location.
The insects look for sheltered spots for the winter, and houses with gaps at windows, doors, vents and siding are the ones they find. The timing is a guide, not a fixed date.
Start the sealing before the weather turns, because that is when the flight begins.
Do brown marmorated stink bugs bite?
No. The University of Maryland Extension says brown marmorated stink bugs do not bite, so the main concern is the nuisance of finding them inside.
Because they do not bite and do not breed indoors, the practical job is removing the ones inside and sealing the way in.
They do not breed indoors. Once they are removed and the gaps are sealed, the household problem usually stops.
How do you keep them out?
Caulk cracks, weather-strip doors and windows, and remove window air conditioners, according to University of Maryland Extension advice. Sealing gaps is the step that does the most good.
Walk the outside of the house and look for gaps where wires and pipes enter, where siding meets the frame and around window and door frames.
A technician can check the house for entry points and show where the sealing is needed.
- Caulk cracks in siding and around frames
- Weather-strip doors and windows
- Remove window air conditioners before the flight
- Check where pipes and wires enter the house
What should you do with the ones already inside?
Vacuum them up or release them outside. The sources used here focus on sealing and removal rather than treating the inside of the house.
Vacuum them up or release them outside, as the advice says.
If they keep appearing in the same room, check the wall and window frames there, since that is where they are finding a route in.
What is spotted lanternfly, and is it a household pest?
Spotted lanternfly is a plant pest, not a household pest. The Maryland Department of Agriculture has a quarantine over all Maryland counties, and sightings are reported to MDA.
The quarantine is about plants and the movement of the insect, so the advice is to report sightings rather than to treat your home for it. Montgomery County's status for the insect is not stated in the sources used.
If you see one, photograph it and report the sighting to MDA. A technician does not treat spotted lanternfly as a household pest.
| Pest | Bites? | What the sources advise |
|---|---|---|
| Brown marmorated stink bug | No | Seal gaps; vacuum or release them outside |
| Spotted lanternfly | Not a household pest | Report sightings to MDA; it is a plant pest under quarantine |
Frequently asked questions
Are stink bugs a danger to children or pets?
They do not bite, and the university advice is to remove them gently. A technician can seal the house so fewer get in. Call (855) 974-4733 if they keep coming in.
Why do they gather on sunny walls?
The insects look for warm, sheltered spots to overwinter, and sunny walls are where they collect before finding a way in. Sealing the gaps around those walls is the usual step.
Should I spray the outside of my house?
The sources used here focus on sealing and removal, so ask a technician whether any treatment is useful for your house.
What do I do if I find a spotted lanternfly?
Photograph it and report the sighting to the Maryland Department of Agriculture. The insect is a plant pest, so it is not a job for a household pest service.
Sources
- Maryland Department of Agriculture – Brown marmorated stink bug control options
- Maryland Department of Agriculture – Spotted lanternfly quarantines
This guide is general information for Montgomery County homeowners, not a substitute for an on-site inspection. Prices are estimates. See our disclaimer.