Can't agree with 'killing every rattlesnake I come across.' Lots of them around here in the desert and along the Rio Grande Bosque (marsh). If they're not in my yard or pasture and an immediate threat to my grandkids or pets I leave them be. They're a necessary part of the environment and I've never seen one go out of its way to attack a human, or any other large animal for that matter. Sure, startle or disturb one and it might strike, but usually it hisses, rattles, and leaves the area. Live and let live....