The nest has been there since May. In May it was the size of a golf ball and one queen was building it alone. August is the month you find out about it.
That is the whole shape of the wasp problem on this coast, and it is why the calls arrive in a three-week burst every year rather than spread across the summer.
What actually changes in August
A yellowjacket colony starts with a single queen in spring. By late August a mature one carries somewhere in the range of four to five thousand workers. It has been growing the entire time and none of that was visible from your patio.
Then two things happen at once. The queen stops laying, so the larvae the workers spent all summer feeding are gone. Those larvae were also the workers' own sugar supply, and losing it sends several thousand wasps out looking for a replacement.
They find it on your table, in the recycling, and around the green bin. So the wasps that ignored you in July start landing on your drink in August, in the same weeks the nest is at maximum size and maximum defensiveness.
It also explains why "leave it, they die in winter" is true and useless. They do die. The first real frost finishes the colony, the nest is never reused, and next spring's queen builds a new one somewhere else. The question is what happens in the eight weeks before that frost.
Two things worth doing yourself
Take away the sugar. Bins shut, recycling rinsed, fallen plums picked up, pet food inside. A patio with nothing on it is a patio wasps stop patrolling.
Then move the bins away from the door you actually use. A large share of late-summer stings happen within a couple of metres of a bin or a doorway, because that is where a person and a foraging wasp arrive at the same moment with no warning.
The third job is a winter one. Once the colony is dead, seal the gap it used. Screen the soffit and roof vents, cap open pipe ends, close the gaps in the siding. A queen goes looking for a cavity in April, and a screened one is a cavity she cannot use. The wasp and hornet guide has the full list.
The mistake that goes wrong most often
A can of wasp spray, pointed at the hole.
It kills the wasps at the opening. Behind the opening there are still thousands, and a chemical hitting the nest sends them out in every direction they can find. In a wall void or a soffit, one of those directions is usually the inside of the house. One of the reviews on our profile is from somebody whose wasps had already got into the house before we arrived, and that is the ordinary version of this, not the extreme one.
Plugging the entrance fails the same way. Wasps chew. Seal an active nest into a wall and they will make a new exit, and it comes out wherever the wood is thinnest. Often that is a light fitting or a baseboard, on the wrong side of the wall.
When it should not be you
A bald-faced hornet nest, the grey football hanging in the open, belongs on that list by itself. It defends a wide radius and it does not need to be touched to decide you are the problem.
Honey bees are the opposite case. Fuzzy, amber, and arriving as a hanging swarm or built comb rather than a papery nest. We do not kill honey bees. Ring us and we will say so on the phone and point you at a beekeeper.
The timing detail that decides whether one treatment is enough
Wasps are treated at low light. Early morning, or last thing in the evening, when the foragers are home and the whole colony is inside.
Treat at two in the afternoon and a good share of the colony is out working. They come back to a nest that has been treated, find it wrong, and start again nearby. That is the usual reason a nest gets treated twice.
It is a small thing that costs a company convenience, because the right hour is rarely the hour that suits a route. It is also the difference between one visit and two.
What the visit looks like
Identify the species first. A yellowjacket in a ground hole, a paper wasp under a railing and a bald-faced hornet in a tree are three different jobs with three different placements.
Find the nest rather than the entrance. In a soffit those can be two metres apart, and treating the hole treats nothing.
Treat at low light, in protective gear, then remove the nest where it can be reached safely, because a dead nest left in place draws beetles as it rots and gives you a second problem in the same cavity.
Seal the cavity once the colony is finished. That is the step that stops the same void being colonised again in April, and it is the one most often skipped.
Expect a few wasps for a day or two afterwards. Those are foragers that were out during the treatment, coming back to a nest that is gone.
Where the local part comes in
Wasps are less regional than most of our work, but housing stock still decides where they end up. Vinyl siding and vented soffits on newer subdivisions in Surrey and Langley give a queen an easy cavity. Older decks and mature hedges in Coquitlam and New Westminster produce more ground and hedge nests, which is the version people walk into with a mower.
If there is a nest by a door right now, that is one of the things we come out for the same day. The inspection costs nothing, and if it turns out to be paper wasps under a railing at the far end of the garden, we will tell you to leave it alone.