Sheep that's in natural fibre (5)

I believe the answer is:

ramie

I'm a little stuck... Click here to teach me more about this clue!

'natural fibre' is the definition.
'ramie' can be an answer for 'fibre' (I've seen this before). I am not sure about the 'natural' bit.

'sheep that's' is the wordplay.
'sheep' becomes 'ram' (male sheep).
'that's' becomes 'ie'.
'ram'+'ie'='RAMIE'

'in' is the link.

Can you help me to learn more?

(Other definitions for ramie that I've seen before include "Tough fibre" , "plant" .)

I've seen this clue in the Sydney Morning Herald.

Want a hint initially instead of a full solution? Install my app