Raced round the tree (5)
I believe the answer is:
cedar
'the tree' is the definition.
(cedar is a kind of tree)
'raced round' is the wordplay.
'round' indicates anagramming the letters.
'raced' with letters rearranged gives 'CEDAR'.
(Other definitions for cedar that I've seen before include "Tree (Lebanese?)" , "Fragrant conifer" , "Tree giving fragrant wood" , "may have needles?" , "Deodar" .)