"I can see this happening. The only way to tell if there's a nest in the ground is to see the "air traffic.""

Right. The area I mow with the push mower is frequently used to conduct physical fitness testing.
I've warned the NCOs to investigate the area for such air traffic before they send recruits running over the lawn.
I cut that area every couple of weeks and now inspect it as well. I've heard of zero turn operators being stung by
hornets, but haven't experienced that yet.