Very little wood ultimately remains (4)
I believe the answer is:
dash
'very little' is the definition.
'wood ultimately remains' is the wordplay.
'ultimately' says to take the final letters.
'remains' becomes 'ash' (remains of a fire).
The last letter of 'wood' is 'd'.
'd'+'ash'='DASH'
(Other definitions for dash that I've seen before include "Hyphen - bother!" , "Hurry; destroy (hopes)" , "instrument panel" , "Hasten; hyphen" , "If you're smart, you'll cut one" .)