Terrifying little beasties... they'll fly right up to you, but they're quite intelligent and not aggressive. They like to look you over, especially if you're wearing bright clothing. We used to catch them when we were kids by whacking them out of the air with a broom and letting them crawl on our arm, just to freak people out. Then, one of the kids put his hand over one, and it stuck that 3/8" long stinger in him just like any other hornet/wasp would. Apparently, they do have their limits on what they'll put up with. The poison from their sting paralyzes their prey. If you've ever seen a cicada laying on the sidewalk and the whole underside of it's body is white, that's what a cicada killer sting does to them. They'll appear to be dead, but in fact they might not be. Anyway, it does horrible things to us, too, if you get stung. Luckily, it's pretty hard to get them to sting you... you almost have to actually sqeeze them in your hand or step on them. They're better at digging than anything you've ever seen. The females will dig a hole back out in only a couple minutes, if you fill it in. Fun to watch the little buggers. They fly real close to the ground, especially around parking lots and disturbed ground. Males are smaller, and don't live very long. They spend their entire lives flying around like that, looking for the females. They're the ones that usually fly right up to you... looking to see if you got any hot, waspy b*tches hanging out on you.