Where Yellow Jackets Build Nests in Toronto Properties
Yellow jackets choose nesting locations that stay hidden until the colony is already large. Underground burrows in Toronto yards are accessed through a 2 to 3 cm ground level opening easy to miss. Wall voids behind brick mortar, siding gaps, or window frames hide active nests for weeks. Eave cavities, soffits, and attic insulation layers on south facing elevations attract nesting queens every spring. A foundress queen selects spots near garbage bins, garden beds, and outdoor dining areas in North York, Scarborough, and Etobicoke.
A nest inside a wall void or underground burrow is always larger than the entry point suggests. Deck structures with sheltered soil underneath and tree hollows near branch junctions are common Toronto nesting hotspots too. The hidden nest grows from a few dozen workers in May to 4,000 by late August all behind a gap you can cover with one finger. By the time buzzing sounds appear inside walls or defensive swarm activity starts near a deck, the colony needs professional removal, not a spray can.