Tree-shaping art (6)
I believe the answer is:
bonsai
'tree-shaping art' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for bonsai that I've seen before include "Art of dwarfing trees" , "Dwarfed ornamental tree or shrub" , "specimen with restricted roots?" , "Japanese art of growing dwarf trees" , "Japanese art of growing dwarf plants" .)