Tying heather round tree (7)

I believe the answer is:

lashing

'tying' is the definition.
(lashing is a kind of tying)

'heather round tree' is the wordplay.
'heather' becomes 'ling' (synonyms).
'round' indicates putting letters inside.
'tree' becomes 'ash' (ash is a kind of tree).
'ling' placed around 'ash' is 'LASHING'.

(Another definition for lashing that I've seen is " punishment by cat?".)

I've seen this clue in The Times.

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