Protected chap had to bring in trees (9)
I believe the answer is:
harboured
'protected' is the definition.
Although both the answer and definition are past participle verbs, I don't understand how one could define the other.
'chap had to bring in trees' is the wordplay.
'chap' becomes 'he'.
'had' becomes 'd' (I've seen this in other clues).
'to bring in' is an insertion indicator.
'trees' becomes 'arbour' (I can't explain this - if you can you should give a lot more credence to this answer).
'he'+'d'='hed'
'hed' enclosing 'arbour' is 'HARBOURED'.
Can you help me to learn more?
(Other definitions for harboured that I've seen before include "Sheltered" , "found shelter" , "concealed" .)