Has certain regrets about the trees (7)

I believe the answer is:

repines

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'has certain regrets' is the definition.
I can't judge whether this definition defines the answer.

'about the trees' is the wordplay.
'about' becomes 're' ('re' means regarding or about).
'the trees' becomes 'pines' (pine is a kind of tree).
're'+'pines'='REPINES'

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(Other definitions for repines that I've seen before include "frets" , "Peers in (anag.)" , "Laments" .)

I've seen this clue in the Evening Standard.

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