I have been buzzed by a Pepsis formosa while in Death Valley. But I was eating a sandwich in the heat and the smell probably attracted it. In general when hiking and photographing in the wilderness, I don't bathe with smelly soaps or wear anything with a smell. Also, certain colors attract certain insects, I especially notice blue and orange, so I generally wear brown and green. A backpacking headnet would also help, I always carry one, and it only weighs about 2 ounces and fits into a pocket. The biting flies are really annoying as they are attracted to sweat and the salts in it. The bees generally go after color or sweet smells like deodorants. Mosquitos are crepuscular and you need to either cover exposed skin or get a DEET type repellant. Clothing that covers the legs and arms and a headnet are the best.