Bees are beautiful but some look really nasty. I lived out in the country with a friend and for the first time planted bok choy, lettuce, kale, and various other greens in his garden. When the kale reached a certain height, I had a ton of really BIG, nasty looking, dark colored bees, every day, stripping the plant bare. I don't know what type of bee they were but someone tried to tell me they were killer bees.