Trees managed to adjust again (5)
I believe the answer is:
reset
'adjust again' is the definition.
('set' can be a synonym for 'adjust' so perhaps 'reset' is OK for 'adjust again')
'trees managed' is the wordplay.
'managed' indicates anagramming the letters.
'trees' anagrammed gives 'RESET'.
'to' acts as a link.
(Other definitions for reset that I've seen before include "adjusted" , "Put back to original state" , "Turn back to zero" , "Restore to zero" , "Replace, resettle or put back again" .)