Plot with hollow lime tree (5)
I believe the answer is:
'tree' is the definition.
(maple is a kind of tree)
'plot with hollow lime' is the wordplay.
'plot' becomes 'map' ('map' can be a synonym of 'plot'**).
'with' says to put letters next to each other.
'hollow' says to hollow out the word (remove centre letters).
'lime' with its middle taken out is 'le'.
(Other definitions for maple that I've seen before include "Tree yielding syrup", "plant", "Canadian flag leaf", "----- leaf: symbol of Canada", "Source of syrup".)