Crossword Genius

Ring a tree surgeon, without great desire for treatment? (8)

Ross

I believe the answer is:

resonate

'ring' is the definition.
(thesaurus)

I don't understand how the remainder of the clue works.

(Other definitions for resonate that I've seen before include "Resound" , "Vibrate sympathetically - ears note (anag)" , "Vibrate at the same frequency" , "make a vibrating effect" , "Continue to ring" .)

I've seen this clue in The Guardian.
Want a hint initially instead of a full solution? Install my app