Birch or spruce (4)
I believe the answer is:
tree
I believe this clue is a double definition.
'birch' is the first definition.
(I've seen this before)
'spruce' is the second definition.
(thesaurus)
(Other definitions for tree that I've seen before include "Conifer, for example" , "Branching diagram" , "eg Ash, oak" , "Diagram representing different relationships" , "''I think that I shall never see / A poem lovely as a ...'' (Kilmer)" .)