Acorn dropper (3)
I believe the answer is:
oak
'acorn dropper' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for oak that I've seen before include "Common deciduous tree" , "Large tree" , "Acorns are its fruit" , "Its seed is the acorn" , "The King of the Forest" .)