Conservative way back from decay (3,3)
I believe the answer is:
dry rot
'decay' is the definition.
(I have seen 'Decay of timber ' mean 'dry rot' so perhaps 'decay' could also mean 'dry rot')
'conservative way back' is the wordplay.
'conservative' becomes 'tory' (I've seen this before).
'way' becomes 'rd'.
'back' shows that the letters should be reversed in order.
'tory'+'rd'='toryrd'
'toryrd' written backwards gives 'DRY-ROT'.
'from' acts as a link.
(Other definitions for dry rot that I've seen before include "hidden decay" , "infestation" , "Timber disease" , "Fungus that causes wood to crumble" , "Decay of wood poorly ventilated" .)