Chart the French tree (5)
I believe the answer is:
maple
'tree' is the definition.
(maple is a kind of tree)
'chart the french' is the wordplay.
'chart' becomes 'map' ('map' can be a synonym of 'chart').
'the french' becomes 'le'.
'map'+'le'='MAPLE'
(Other definitions for maple that I've seen before include "Tree providing Canada's national emblem" , "Tree with winged seeds" , "Hard light-coloured wood used for furniture" , "Tree; sugar from it" , "Syrup-yielding tree" .)