In my (old) hometown of Fenton, Michigan, in the Nineteen Fifties, they had a Twelfth Night Celebration where all the Christmas trees were collected in a safe part of one of the large city parks; and under the volunteer fire brigade's watchful eye were, were burned. Right out there in the open, with the sanction of the civil authorities!
My parents told us that the practice came from an old, maybe pagan, belief that all of the evil spirits trapped in your home were burned in the event.
Our Mom was the source of that story, she had others.
I remember that, in Bethesda, Md. Definitely in the ‘fifties. I was three or four years old. I think they did it on the grounds of the public grade school.