Sep 19, 2023 - News

How to deal with pesky yellow jackets during fall

Buzz buzz. Photo: Creative Touch Imaging Ltd./NurPhoto via Getty Images

If you've been noticing more yellow jackets than usual, you're not wrong.

Driving the news: By mid-September, they have built up nests to their maximum population capacity (up to 2,000) and are increasingly protective of the last batch of larvae laid ahead of winter, according to George Poinar, an entomologist at Oregon State University.

What they're saying: "The colonies slowly build up," Poinar tells Axios. "They are small in the spring, larger in the summer and immense in the fall as they produce more and more workers."

  • It's not a Pacific Northwest phenomenon either, but nationwide.

What's happening: Those workers are coming for your lunch. Eager to stock up on food to ensure the future queens survive the winter, yellow jackets are ruthless in their persistence.

  • "They will land on your plate and even take food from your mouth," Poinar tells Axios.

The intrigue: Yellow jackets, which are a type of wasp, are not pollinators, but predators. They're carnivores, but in the fall they catch a sweet tooth and can be found snacking on fallen fruit fermenting in the sun.

  • Unlike bees, yellow jackets can be sting-happy — they don't meet their fate after brandishing you with a new welt and are more than content to do it again.

Be smart: Yellow jacket nests are built from wood fiber and can be found either entirely underground or hanging from tree limbs or on the side of buildings.

  • You can get rid of individual wasps by using traps or powdered insecticide — but the best way may be to leave them alone, Poinar says, since the majority will freeze or starve to death come winter.
  • Yellow jackets interpret swinging arms and limbs as attacks on their nearby nest and will likely retaliate with aggression. If one mistakes you for food, let them investigate then fly away.

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