Does formic acid often make bees aggressive?

This whole year I’ve never so much as had a bee land on me. They’ve been super chill, and though they haven’t produced much, it’s been super easy to work with my Carniolans.

Today I added 2 Formic Pro strips to the tops of my lower brood box, and I have to assume that’s what’s pissing them off. About 20 minutes ago I was standing about 15-20 feet away from my hive in my yard when I suddenly get stung.

They’re never like this, which is why I’m a little concerned. There is a group of wasps that sometimes fly near the hive, but that’s been an issue for a while so I can’t really believe they’re the sole reason for this.

Have any of you experienced anything similar? Thanks.

Hi Riheco, welcome to the forum. I can’t speak for formic acid, on account that we don’t have varroa mites yet.

Just generally speaking about bees getting aggressive. I learned a few years ago that bees can detect an increase in Co2 in the air. The detection of an increase in Co2 triggers bees defensive mechanism. In the natural world, that helps bees to recognize predators before they invade their hive. If they can discourage invaders from raiding their hive, that’s a job well done. They look for the source of the Co2, because in my opinion that’s where they can sting to cause the most pain. Sometimes they’ll do that, which gives us a chance to move away, or take evasive action. Other times they’ll just attack without any warning, stinging us on the first bit of exposed skin they find.