To identify a snake hole, look for openings in the ground that are newly visible. Snakes don't construct a dwelling, they inhabit an abandoned rodent's burrow or a naturally-occurring hole. When the snake enters a rodent's former dwelling, it removes the obstructions that previously hid the entrance for security.
The absence of spider webs and debris around a tree's hole or rock crevice is an indicator of snake activity. A snake brushes away debris as it enters and exits from its den. Snakes seek shelter to lay eggs and avoid predation, and they favor tight spaces. Snakes don't dig, but they do burrow below the frost line to survive in the winter.