Tree used in sacred fires (3,3)

I believe the answer is:

red fir

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'tree' is the definition.
I don't know anything about this answer so I cannot tell whether this works.

'in sacred fires' is the wordplay.
'in' indicates the answer is hidden within the clue.
'RED FIR' can be found hidden inside 'sacred fires'.

'used' acts as a link.

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

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