Tall tree (3)
'tall tree' is the definition.
(I've seen this before)
This is the entire clue.
(Other definitions for poplar that I've seen before include "Tall fast-growing tree; East London area" , "Tree of north temperate regions, with flowers borne in catkins" , "Tall tree (which may tremble?)" , "Tree as tulip-tree, aspen" , "Slender tree with quivering leaves" .)
'tall tree' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for fir that I've seen before include "Kind of cone-bearing tree" , "Scots pine" , "Evergreen tree for Irish men?" , "Pine tree for Gaelic men?" , "Evergreen conifer" .)