Tree; neat and smart (6)
I believe the answer is:
spruce
I believe this is a double definition.
'tree' is the first definition.
(spruce is a kind of tree)
'neat and smart' is the second definition.
(I've seen this before)
(Other definitions for spruce that I've seen before include "Well-dressed" , "Smart, trim" , "Smart and tidy - tree" , "Coniferous tree" , "Natty as a tree" .)