Some people can smell Rattlesnakes and Water Moccasins before they ever see them. To me, Rattlers smell like licorice candy and Moccasins have a smell like old wet newspapers. I think the snakes use it as a warning if someone is too close.
I have located several that I didn’t see until I started searching after smelling them.
No kidding? I never heard that. Does it work with copperheads? Those things are nasty and their bite will have your leg off.