Go through wood on the way back, finding shrub (6)
I believe the answer is:
Here is my best explanation:
'shrub' is the definition.
(myrtle is a kind of shrub)
'go through wood on the way back' is the subsidiary indication.
'go' becomes 'try' (**).
'through' indicates putting letters inside (I've seen this in other clues).
'wood' becomes 'elm' (elm is a kind of wood).
'on the way back' is a reversal indicator.
'try' put into 'elm' is 'eltrym'.
'eltrym' reversed gives 'myrtle'.
'finding' is the link.
(Other definitions for myrtle that I've seen before include "Evergreen shrub with pink or white flowers and dark berries", "Shrub; female name", "Shrub with white flowers and aromatic berries", "Evergreen shrub; name", "Bush", "Evergreen shrub with blue-black berries", "Termly (anag.)", "Evergreen shrub - try elm (anag)", "Evergreen shrub with dark leaves and white flowers" and "Girl".)