A yellowjacket colony starts in April with one queen and a nest the size of a golf ball. By August it holds a few thousand workers and has run out of the sugar its own larvae used to supply, which is when it starts showing up at your table.
Signs in the house
- A steady line of wasps entering the same point in the lawn or a retaining wall.
- Traffic that continues at dusk, when solitary wasps have stopped flying.
- Staining or a faint papery sound on an interior wall shared with a soffit.
- Activity concentrated within thirty feet of one spot — the nest is inside that circle.
Size
12-16 mm.
Active
May through the first hard frost. Worst in August and September.
Nests in
Ground burrows about seventy per cent of the time; the rest in wall voids and soffits.
Risk
Sting risk, serious for anyone with an allergy.
Treatment window
Same day, May through October.