Son tries to find garden tool (6)
I believe the answer is:
shears
'garden tool' is the definition.
(large cutting tool used for gardening)
'son tries' is the wordplay.
'son' becomes 's' (genealogical abbreviation for son).
'tries' becomes 'hears' (as in trying or hearing in a trial).
's'+'hears'='SHEARS'
'to find' acts as a link.
(Other definitions for shears that I've seen before include "Garden cutting implement" , "Big scissors" , "Hedge cutting tool" , "fractures under pressure" , "Grass cutters" .)