Screen 150 trees (5)

I believe the answer is:

cloak

'screen' is the definition.
(thesaurus)

'150 trees' is the wordplay.
'150' becomes 'cl'.
'trees' becomes 'oak'.
'cl'+'oak'='CLOAK'

(Other definitions for cloak that I've seen before include "Garment - conceal" , "Veil with cape" , "Cover, hide" , "Camouflage" , "Loose outer garment" .)

I've seen this clue in The Guardian.

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