Are hornets very aggressive?

Hornets are not very aggressive in the sense of seeking out humans to attack, but they are highly defensive and will become aggressive when their nest is threatened, when they feel trapped, or when they are provoked, and their defensive behavior can be intense because they can sting multiple times and release alarm pheromones that recruit other hornets. Species like bald-faced hornets, European hornets, and Asian giant hornets are social and live in colonies that they protect vigorously, so if you come within a few feet of a nest, make vibrations by mowing, or swat at a foraging hornet, they may perceive you as a threat and sting. Away from the nest, foraging hornets are generally not aggressive and will usually ignore people and focus on hunting insects and gathering sugars. Compared to yellow jackets, hornets are often less likely to bother people at picnics, but their sting is more painful and they defend a larger perimeter around the nest. Late summer colonies are largest and more defensive. To avoid aggression, keep distance from nests, do not swat, keep food covered outdoors, avoid strong perfumes, move slowly near hornets, and if a nest is near a home or high-traffic area, contact professional pest control for safe removal rather than trying to remove it yourself.