Field marshal whose targets are rather woolly? (8)
I believe the answer is:
sheepdog
'field marshal whose targets are rather woolly?' is the definition.
(a sheepdog looks after woolly sheep in a field)
This is the entire clue.
(Other definitions for sheepdog that I've seen before include "Farmer's herding helper" , "could it be Old English?" , "eg Border collie" , "Pastoral assistant?" , "One drives over fields" .)