Students after misbehaving harm certain shrubs (7)

I believe the answer is:

rhamnus

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'students after misbehaving harm certain shrubs' is the definition.
I can't tell whether this definition defines the answer.

'students after misbehaving harm' is the wordplay.
'students' becomes 'nus' (National Union of Students).
'after' is a charade indicator (letters next to each other).
'misbehaving' is an anagram indicator.
'harm' anagrammed gives 'rham'.
'nus' put after 'rham' is 'RHAMNUS'.

Can you help me to learn more?

(Another definition for rhamnus that I've seen is " buckthorn".)

I've seen this clue in The Times.

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