Rotten tree not in keeping here (9)

I believe the answer is:

retention

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'keeping here' is the definition.
'retention' can be an answer for 'keeping' (thesaurus). I'm not certain of the 'here' bit.

'rotten tree not in' is the wordplay.
'rotten' indicates an anagram.
'tree'+'not'+'in'='treenotin'
'treenotin' anagrammed gives 'RETENTION'.

Can you help me to learn more?

(Other definitions for retention that I've seen before include "holding" , "Enter into custody" , "memory" , "maintenance" , "Capacity to remember" .)

I've seen this clue in The Globe and Mail.

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