Nuts about unprotected park trees (6)

I believe the answer is:

carobs

'trees' is the definition.
(carob is a kind of tree)

'nuts about unprotected park' is the wordplay.
'nuts' becomes 'cobs' (cob is a kind of nut**).
'about' means one lot of letters goes inside another.
'unprotected' says to take the centre.
The middle letters of 'park' are 'ar'.
'cobs' enclosing 'ar' is 'CAROBS'.

(Another definition for carobs that I've seen is " Pods used as chocolate substitute".)

I've seen this clue in The Telegraph.

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