When are wasps and yellowjackets most active in Detroit?
Wasp nests start small in spring, grow through summer and are typically at their largest and most aggressive in late summer and early fall. After the first hard frosts the colony dies off and the old nest is not reused, though queens overwinter in sheltered spots and start new nests the next year.
A cold Detroit winter resets the cycle every year. The nest you see in August is gone by the time snow arrives, and the new one begins when the queen comes out in spring. That is why removing an empty nest in November is usually about tidying up, not about stopping a problem.
Late summer is also when wasps are drawn to soda cans, fruit and trash, so a worker at your picnic table is not necessarily a sign of a nest at the house. A technician helps you work out whether the nest is on your property.
Can I remove a wasp nest myself?
Small exposed paper wasp nests can sometimes be handled by a careful homeowner at dusk, but yellowjackets, wall nests and high nests are risky. Stings can be painful for anyone and dangerous for people with allergies. If you have had a serious reaction to a sting before, do not attempt it.
Store-bought sprays work on exposed nests only when they reach the colony, and spraying a hidden entrance can push wasps toward the inside of the house instead of out. Never block a wall or ground entrance yourself. Trapped wasps will look for another way out, and that can be through a light fixture or a gap in the drywall.
What do I do if I get stung or swarmed?
Move away from the nest quickly, protect your face, and get indoors. Wash stings with soap and water and use a cold pack. Call 911 or get emergency help right away if there is trouble breathing, swelling of the face or throat, dizziness or a rash spreading beyond the sting.
Multiple stings can cause problems even in people with no known allergy. Keep children and pets away from the area until a technician has dealt with the nest, and do not return to the spot to look.
Why do wasps nest in soffits and wall voids?
Wasps look for dry, sheltered, protected cavities. Soffit vents, loose siding, gaps around windows and open fascia boards give them access to warm, dark spaces. Once inside, a nest can grow between the wall layers or in the attic, and the first sign may be wasps entering a crack no wider than a pencil.
The same entry points that let wasps into a wall often let squirrels and raccoons into an attic. A gap that is large enough for one can be repaired for both. Ask the technician to look at the whole roofline while on site.
How can I tell where the nest is?
Watch the flight path for a few minutes from a safe distance on a warm afternoon. Wasps travel in a fairly straight line between the nest and where they feed, so a steady stream into one gap, hole or corner points to the nest. Do not stand close, and do not shine a light at it after dark.
Write down what you see before you call: the spot, the height, and whether the insects go into a gap or hang on an open nest. That lets the technician bring the right equipment and tell you in advance whether the job is likely to be simple.
If wasps are coming indoors, take note of the room and whether you hear buzzing in the wall. Indoor wasps are often from a nest in a wall void or attic, and may be reaching the room through a light fixture, an outlet gap or a window frame.