Secret store of wood found by saint (5)
I believe the answer is:
'secret store' is the definition.
(I've seen this before)
'wood found by saint' is the wordplay.
'wood' becomes 'ash' (wood from an ash tree).
'found by' is a charade indicator (letters next to each other).
'saint' becomes 'st' (abbreviation).
'ash' after 'st' is 'STASH'.
'of' acts as a link.
(Other definitions for stash that I've seen before include "Secret store of valuables" , "Hide (something) away" , "(Illegal) hoard" , "Hide in a secret place" , "(Hidden store of) drugs" .)