Raced out of control into a tree! (5)
I believe the answer is:
cedar
'a tree' is the definition.
(cedar is a kind of tree)
'raced out of control' is the wordplay.
'out of control' indicates an anagram.
'raced' anagrammed gives 'CEDAR'.
'into' is the link.
(Other definitions for cedar that I've seen before include "Fragrant conifer" , "Cypress-like tree" , "Raced around a mighty tree" , "Great hardwood tree associated with Lebanon" , "Tree (Lebanese?)" .)