Layers beneath kippers of crushed leaves (12)

I believe the answer is:

groundsheets

'layers beneath kippers' is the definition.
(you might sleep or 'kip' on a groundsheet)

'crushed leaves' is the wordplay.
'crushed' becomes 'ground' ('ground' can be a synonym of 'crushed').
'leaves' becomes 'sheets' (I've seen this before).
'ground'+'sheets'='GROUNDSHEETS'

'of' is the link.

I've seen this clue in The Telegraph.

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