Church official seen in tree (5)
I believe the answer is:
elder
I believe this clue is a double definition.
'church official' is the first definition.
(as in church elders)
'tree' is the second definition.
(elder is a kind of tree)
'seen in' acts as a link.
(Other definitions for elder that I've seen before include "Tree; of greater age" , "Senior tribal figure" , "Senior - presbyter" , "more mature" , "Senior type of tree?" .)