The hollow tree managed to wobble (6)
I believe the answer is:
teeter
'to wobble' is the definition.
(I've seen this before)
'the hollow tree managed' is the wordplay.
'hollow' suggests removing the centre (the word is hollowed out).
'managed' indicates anagramming the letters.
'the' with its middle removed is 'te'.
'tree' is an anagram of 'eter'.
'te'+'eter'='TEETER'
(Other definitions for teeter that I've seen before include "Rock gently on the edge" , "Rock precariously on the edge" , "Balance unsteadily" , "waver" , "Move with little assurance" .)