Recovering fleece found by valley track (12)
I believe the answer is:
convalescent
'recovering' is the definition.
('convalescent' can be a synonym of 'recovering')
'fleece found by valley track' is the wordplay.
'fleece' becomes 'con' (I've seen this before).
'found by' is a charade indicator (letters next to each other).
'valley' becomes 'vale' ('vale' can be a synonym of 'valley'**).
'track' becomes 'scent'.
'con'+'vale'+'scent'='CONVALESCENT'
(Other definitions for convalescent that I've seen before include "Novel accents (anag) -- gradually recovering health" , "One recovering from medical treatment" , "getting back to normal" , "Recuperating" , "One may be showing improvement" .)