The smell emitted by the plant is irritating for mice and they try to avoid them. Poo from bobcats, snakes, and cats are also effective mice deterrent because of their distinct smell. That smell scares mice away due to their natural fear on their predators. Pet stores have products that contain this unique smell which you can buy to spread over your house to keep mice away.
1) A myth exists that a cucumber smell comes from rattlesnakes. 2) The Tongue Mountain Range is known for harboring rattlesnakes. 3) The only place I have ever smelled random cucumber is the Tongue Mountain Range. Which leads me to believe the tiny minority, that rattlesnakes do in fact give off a cucumber smell.
A cottonmouth holds its head higher out of the water when swimming while undisturbed. A water snake often sits low in the water with only part of its head and nose visible. Both emit a foul odor when threatened, but the water moccasin's smell is more like cucumbers, while water snakes smell like rotten cabbage. Both have triangular heads, but the cottonmouth has dimpled pits between its eyes and nostrils, while water snakes do not.