Oak seeds (6)
I believe the answer is:
acorns
'oak seeds' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for acorns that I've seen before include "'Great oaks from little ...... grow'" , "'From little . . . . . . mighty oaks do grow'" , "Fruits of the oak tree" , "Seeds of the oak" , "wild fruit" .)