Strip down poor piece finally about conservationists (9)
I believe the answer is:
dismantle
'strip down' is the definition.
(I've seen this before)
'poor piece finally about conservationists' is the wordplay.
'poor' becomes 'dismal' (dismal can mean poor or bad-quality).
'finally' suggests the final letters.
'about' means one lot of letters goes inside another.
'conservationists' becomes 'NT' (abbreviation for National Trust).
The final letter of 'piece' is 'e'.
'dismal'+'e'='dismale'
'dismale' going around 'nt' is 'DISMANTLE'.
(Other definitions for dismantle that I've seen before include "Take to bits" , "Unrig" , "Take apart" , "Take to pieces" , "Pull to pieces" .)