Picture timber being felled? (7)
I believe the answer is:
woodcut
'picture' is the definition.
(I've seen this before)
'timber being felled?' is the wordplay.
'timber' becomes 'wood' (I've seen this before).
'being felled?' becomes 'cut' ('cut' can be similar in meaning to 'felled').
'wood'+'cut'='WOODCUT'
(Other definitions for woodcut that I've seen before include "Printing block" , "Type of print" , "Relief work" , "Engraving" , "Old book illustration" .)