Can one sit on a tree stump or is there a spiritual danger?
I remember hearing such a thing, but I don't remember where.
Pesachim 111b - If one steps over a [fallen] palm tree - if it was cut down, he will be killed; if it was uprooted, he will die. If he put his foot on it, there is no problem.
doesn't say about sitting but this is probably the root of that statement. Furthermore, I was told that all the demons were banished by the maharsha, so this does not seem to apply today. someone please source this last statement.