You shouldn't let the probe touch the ground. If you're going to dangle it having it at least a few inches off the ground is best.
I have mine glued into a cable strap and the strap glued to the rim of the rhp. It has worked great for years. The probe doesn't touch the rhp hearing element but it's in the direct path of the outer edge. Setting it up like this eliminates the snakes ability to move it, lay on it, soak it, etc.