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 "Shrub with white flowers and aromatic berries", "Fragrant evergreen shrub", "Evergreen shrub; name", "Evergreen shrub with dark leaves and white flowers", "Evergreen shrub with pink or white flowers and dark berries", "Try Mel for the flowering shrub", "Shrub; female name", "Shrub with purple-black oval berries", "Shrub - try elm (anag)" and "Plant with aromatic blue-black berries".)