Grain scattered in drained marshes' borders (7)

I believe the answer is:

margins

'borders' is the definition.
('margin' can be a synonym of 'border')

'grain scattered in drained marshes'' is the wordplay.
'scattered' is an anagram indicator.
'in' indicates putting letters inside.
'drained' means to remove the middle letters.
'marshes' with its centre taken out is 'ms'.
'grain' anagrammed gives 'argin'.
'argin' going within 'ms' is 'MARGINS'.

(Another definition for margins that I've seen is " Profits".)

I've seen this clue in The Independent.

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