The wood trade (4)
I believe the answer is:
deal
This clue is a double definition.
'the wood' is the first definition.
(deal is a kind of wood)
'trade' is the second definition.
('deal' can be a synonym of 'trade')
(Other definitions for deal that I've seen before include "Give several people a hand" , "split deck" , "Bargain, contract" , "Wood - piece of business" , "Hand out playing cards" .)