This is an old phrase that has become condesed and reversed in the original meaning. Originally to be in a tree was to be stuck somewhere mentally, emotionally or situationally that you could not easily escape from on your own. The
proverbial cat stuck in a tree that the proverbial fireman needs to rescue. Of course, cats are perfectly capable of getting out of trees, which is why we do not see many cat
skeletons in trees. However, it is not uncommon to see a fellow human, so distraught be whatever is affecting them, they they have lost their way and cannot see
a way out. Proverbially, they are stuck in a tree and need someone to talk them down, out of their tree.
Example:
My life had dust gone insane, fortunately Jimmy came over and talked me down,
out of my tree.
Beck: Sarah Palin "talked me down out of my tree" after my "
one moment of
real fear"