Acorn producer (3-4)
I believe the answer is:
oak-tree
'acorn producer' is the definition.
(I've seen this before)
This is all the clue.
(Other definitions for oak-tree that I've seen before include "Acorn bearer" , "Old plant (round which to tie a yellow ribbon?)" , "The tall perennial Quercus" , "Acorn producer" , "Tree of the genus Quercus" .)