Anyone fed up with checking their glass of raspberry soda for wasps before taking a slug on a hot Swedish summer's day should act now to prevent it.
"If you're scared witless of wasps, now is the time to remove them," insect researcher Julia Stigenberg told the TT news agency.
The big fat wasps that have just appeared is the queen wasp. Killing her means less need to remove dangerously placed nests later in the season.
"If you don't, there will only be more and more wasps later on," Stigenberg said, adding that she just found a nest hidden in a boot at her summer cottage.
The expert added that wasps can be helpful in the garden, too, by eating larvae crawling over fruit trees, for example.
"Wasps are mean at eating other insects," she said. "If people understood what wasps do, maybe they'd put up with them a bit more."