Storing wood — it's a pain collecting it (8)
I believe the answer is:
stashing
'storing' is the definition.
'wood it's a pain collecting it' is the wordplay.
I cannot really understand how this works, but
'wood' could be 'ash' (wood from an ash tree) and 'ash' is found within the answer.
'pain' could be 'sting' (sting is a kind of pain) and 'sting' is located in the leftover letters.
No letters remain.
This explanation may well be incorrect...
Can you help me to learn more?
(Other definitions for stashing that I've seen before include "Storing in a secret place" , "Stowing away" , "stocking, secretly" .)