It is not unusual in the southern US states to see a bottle tree in a yard close to a home.
It is said that bad spirits that roam at night are attracted to the colors of the bottle and hide in them. There they will get trapped, and in the morning the sunshine will kill them.
Most popular are the “blue bottles” which represents water and sky.
The bottles can be placed on a twisted or formed piece of metal or placed directly on the limbs of a tree. I have seen them even placed on a fence post.