On the Feast of the Exaltation, according to folk beliefs, snakes leave for the forests or hide in the ground. In Polesie, people believe that this day is “the feast of the snakes” or “their celebration,” and consider it the last day of their spring activity. On this day, snakes gather together and coil into balls; some even say it is “the last time they’ll have their revel.” That is why people do not go mushroom picking in the forest on the Feast of the Exaltation, for fear of encountering snakes. In Karelia, it is said that Saint NidsemHuil summoned all the snakes to an assembly to identify those who had done evil, and forbade them to go underground, condemning them to death.

— Gura. *Animal Symbolism in Slavic Folk Tradition*, p. 338