Pine tree, for one (7)
I believe the answer is:
conifer
'pine tree for one' is the definition.
(pine tree is a kind of conifer)
This is the entire clue.
(Other definitions for conifer that I've seen before include "Evergreen tree" , "The tree doesn't lose its leaves" , "Fir or larch, for example" , "E.g. yew, pine or fir" , "In force (anag.)" .)