Oklahoma's "Wheat Capital” (4)
I believe the answer is:
enid
'oklahoma's wheat capital' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for enid that I've seen before include "Dine with Ms blyton, writer" , "& 18 Down Children's author" , "- Blyton, children's writer" , "Woman" , "- Blyton, twentith century writer" .)