Tree house abroad entered with unending caution (7)
I believe the answer is:
cascara
'tree' is the definition.
'house abroad entered with unending caution' is the wordplay.
'house abroad' becomes 'casa' ('house' in Spanish).
'entered with' is an insertion indicator.
'unending' means to remove the last letter (the word doesn't have its end letter).
'caution' becomes 'care' (synonyms).
'care' with its final letter removed is 'car'.
'casa' enclosing 'car' is 'CASCARA'.
(Other definitions for cascara that I've seen before include "Bark purgative" , "purge" .)